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Nuclear
is for Life
A Cultural
Revolution
Wade Allison MA DPhil
Fellow of Keble College
Professor of Physics (Emeritus)
University of Oxford, UK
Published by
Wade Allison Publishing
© Wade Allison 2015
All rights reserved
No part of this publication may be reproduced,
stored on a retrieval system, or transmitted, in any
form or by any means, without explicit permission
from the author.
Enquiries should be sent to
wade.allison@physics.ox.ac.uk
Published in paperback (2 December 2015)
ISBN 978-0-9562756-4-6
Last saved 4 November 2015
Website http://www.nuclear4life.com
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For
George, Edward, Minnie,
Joss, Alice, Alfie
and
others of their generation
who inherit what we leave
About the author
Wade Allison is a Fellow of Keble College and and an Emeritus Professor of
Physics at the University of Oxford. There he studied and taught for 40 years,
covering subjects such as electromagnetic radiation, particle and nuclear
physics, and medical physics. His first book was an advanced student book:
Fundamental Physics for Probing and Imaging (2006). Concerned that many
otherwise educated people have significant misconceptions about radiation
and nuclear energy he wrote his second book for a wider audience: Radiation
and Reason, the Impact of Science on a Culture of Fear (2009). It attracted
considerable attention around the world, especially following the accident at
Fukushima Daiichi in 2011, after which it was published in Japanese and
Chinese. Since then he has been to Japan several times to lecture and to visit
teachers, community leaders, doctors and evacuees in the region affected by
the accident. Incidentally, he has never had any connection with the nuclear
industry.
Some reviews of Radiation and Reason
“Sensational.” Simon Jenkins, The Guardian
"I very much agree with the conclusions of this book, and am very pleased to
see them presented in a style that makes them accessible to the general
reader." Sir Eric Ash, FRS
"If Professor Allison´s well-documented arguments are right – and if people
can be persuaded to examine them! – his book gives us a little more hope of
confronting the problems posed by both dwindling fossil fuel reserves and the
release of their waste products into the atmosphere." Michael Frayn,
playwright and author
“This is an important and useful book. Wade Allison's message is simple -
we've got it wrong about nuclear power. We've over-reacted to the level of
risk posed by low level radiation exposure, and because of that we make
nuclear power ridiculously expensive. The arguments are very powerful.”
Brian Clegg, Popular Science website
"Why I'm becoming a pro-nuke nut..... The other scholar challenging my
nuclear views is Wade Allison....we must consider all alternatives available
to us — including nuclear energy, which just a few months ago I fervently
opposed.” John Horgan, Scientific American
“Even if you disagree with where Allison takes his arguments, a large part of
the book is a good accessible review of the science of radiation and its
biological effects. This in itself makes it a potentially valuable read for
activists interested in nuclear and environmental issues.” Peace News
Contents
Preface
Chapter 1 Many Misunderstandings ........................... 1
Chapter 2 Intelligence as an Aid to Survival ............... 15
Chapter 3 Rules, Evidence and Trust ......................... 29
Chapter 4 Energy to Support Life ............................... 59
Chapter 5 Absorbed Radiation and Damage .............. 87
Chapter 6 Effect of Large Radiation Doses ............... 123
Chapter 7 Protected by Physical Science ................... 155
Chapter 8 Protected by Natural Evolution ................. 177
Chapter 9 Society, Trust and Safety ........................... 209
Chapter 10 Science Distorted by Frightened Men ..... 235
Chapter 11 Natural Philosophy of Safety ................... 255
Chapter 12 Life Without Dragons .............................. 267
Selected References ..................................................... 281
Glossary ....................................................................... 282
Lists of Tables and Illustrations ................................... 285
Index ............................................................................ 287
Preface
This book expands on the message of Radiation and Reason (2009)
following the Fukushima accident (2011). It is a broader study of the
historical, cultural and scientific interactions of radiation with life; it asks
why society takes such a cautious view of nuclear technology; it looks at
the effects of nuclear accidents and other radiation exposures; it looks at
the efficacy of safety, as provided by nature and as imposed by regulation;
it explains how biological evolution prepared life to survive exposures to
low and moderate levels of radiation; it asks if nuclear energy would be
expensive, if normal levels of information, education, safety and design
were applied.
These questions are not difficult, though far too few people are asking
them. I suggest that the answers are important for everyone on the planet
in view of atmospheric pollution and its effect on the climate. I shall be
encouraging my grandchildren to read and look with fresh eyes at the
amazing natural world that is our home. May they and their
contemporaries understand better the beauty of what they see, and so look
after it better than my generation has done.
Chapter 1 gives a short outline. The points it makes are supported by the
evidence and discussion given in the body of the book. Chapters 2 and 3
discuss public confidence, trust in nuclear energy and the events at
Fukushima. Chapter 4 tells how the use of energy has changed as life has
evolved. Chapter 5 is about the science of radiation and how it affects life;
including an explanation of the conventional LNT (Linear No-Threshold)
model and why it is mistaken. More evidence of the effect of radiation on
life from accidents and experiments is provided in Chapter 6. Chapters 7
and 8 cover the extraordinary natural protection of life afforded by the
physical and biological sciences, each in their separate way. The task of
outlining an evidence-based safety regime that takes proper account of
nature is discussed in chapter 9, which then goes on to ideas of how this
might be explained to the public who have been misinformed for so long.
Chapter 10 is a historical account of the view that radiation is dangerous
and why authorities still support this view in spite of the overwhelming
evidence that it is mistaken. This historical account of the people
involved, and why they behaved as they did, makes an interesting story
that is more about human nature and less about science. Chapter 11 is a
discussion of the relationship between trust in science, religious culture
and natural philosophy. Chapter 12 summarises a number of conclusions.
The subject matter is far reaching and readers may wish to move from
chapter to chapter, skipping sections that seem too obvious or demanding;
to help in this some harder passages are shown enclosed in boxes. Some
notes and references are given in square brackets and listed at the end of
each chapter, but I do not imagine that readers will need to look at all of
these. At the end of the book is a short list of recommended books,
articles, videos and websites, referenced by labels [SR1] to [SR10]. There
are also a glossary, lists of tables and illustrations and an index. Those
illustrations that are quantitative are described as diagrams or graphs;
others may be merely descriptive or sketches.
A study such as this is not possible without the help of many people. I
have made many friends, some of whom I have never met but whose
contributions have been essential and whose opinions I have come to
respect. Mohan Doss, Rod Adams, Jerry Cuttler and other members of
SARI, the international ad hoc group. Their knowledge and determination
give great hope that one day radiation and nuclear energy will be
accepted. James Hollow who read through drafts of Radiation and
Reason, gave me unstinting assistance in Tokyo for this book too, also
with help from Paul Eden. I also thank others who introduced me to useful
contacts and information in Japan including David Wagner, Tateiwa san,
Takamura san, Dr Oikawa, Dr Hashidume, Professor Tom Gill and Shoji
Masahiko. I thank John Brenner, Ikeda sensei and Takayama san for their
support, and also other members of SRI (Society for Radiation
Information) in Japan for making me welcome on my recent visits. Those
who have worked painstakingly through my writing and wielded a red pen
with justice have my profound thanks: John Priestland, T.R., Clive
Elsworth, Richard Crane, Richard Walker and, of course, my wife Kate
who has also encouraged me and kept me going over the months and
years. Thanks too to all members of my family who have seen less of me
recently than they should. Thank you to Royston Robertson for drawing
the cartoons, to Richard Crane and Michelle Young for building the
website and to my son Tom for designing the cover, also to York
Publishing Services who have been most helpful and held my hand during
the publishing stage, as they did for Radiation and Reason. Inevitably and
regrettably, when all is done, there are many omissions and no doubt some
mistakes too, that should be laid at my door.
Wade Allison
Oxford
October 2015
Nuclear is for Life. A Cultural Revolution. 1
Chapter 1: Many Misunderstandings
Gregory: Is there any other point to which you would wish to draw my
attention?
Sherlock Holmes: To the curious incident of the dog in the night-time.
Gregory: The dog did nothing in the night-time.
Sherlock Holmes: That was the curious incident.
Silver Blaze (1892), Sir Arthur Conan Doyle
Summary 1
Climate change 2
Safety and medical care 3
Historical reasons for nuclear mistrust 7
Education, authority and confidence in society 9
Waste, cost and vested interests 9
The task ahead 11
Note on Chapter 1 13
Summary
The radiation disaster at the Fukushima Daiichi nuclear power station that
occurred in March 2011 is curious. There was considerable escape of
radioactivity and the incident was ranked in the most serious category
possible. That there was not one health casualty from the radiation is a piece
of evidence that calls for explanation.
We have got it wrong about the contribution that nuclear science can make to
life. We should examine the hard evidence available not only from
Fukushima but also from other accidents, clinical medicine and elsewhere in
the light of current scientific knowledge. Critical to this conclusion is the way
that living tissue responds to radiation (strictly, ionising radiation). This
response evolved very early in the story of life on Earth, and without it life
would not have survived. But its effectiveness is explicitly ignored in the
formulation of current safety provisions, in spite of the paradoxically small
loss of life in all nuclear accidents. In drawing up successful safety
regulations to control conventional industrial and agricultural hazards, risks
are considered calmly and in proportion. However for historical and cultural
reasons, the same is not true for radiation hazards: these reasons are explored
and clarified in later chapters.
2 Chapter 1: Many Misunderstandings
For nearly a century our understanding of what nuclear technology has to
offer has been obscured by ultra-cautious authorities hiding behind
fragmented expertise. The broad picture, though muddied by history and
assumed to be difficult, is not hard to appreciate in simple common sense
terms. Most people are unaware of the large share of the physical world that
is nuclear matter, and the amazing contribution that its use can make to
prospects for a densely crowded Earth. Indeed, if nuclear energy is not the
environmental threat that many suppose, it is the answer to several of the
most serious problems faced by mankind: atmospheric pollution, and
shortage of clean energy, clean water and food. In any democracy this matters
because the electorate should understand the issues. Otherwise, irrational
swings of mood or fashion affect decisions.
Our supremacy on Earth has depended on knowledge, confidence and
teamwork through openness and mutual trust. However, in the case of nuclear
technology these links have been broken and a massive cultural shift is
needed to mend them. This is not a matter for top-down committees as much
as explanation by individuals, engaging with simple evidence to build
people's trust in science and society. Illuminated in this way, nuclear
opportunities should become clear and no longer be a source of fear and
obscurity.
Climate change
Carbon-based fuels are polluting the atmosphere. The concentrations of
methane and carbon dioxide are rising fast every year and are now two to
Illustration 1 Graphs showing the extraordinary increase of methane
and carbon dioxide atmospheric concentrations in recent times
Nuclear is for Life. A Cultural Revolution. 3
four times higher than they have been for several hundred thousand years.
Given the known properties of these greenhouse gases, it comes as no
surprise that the polar ice caps are melting and the world temperature is
rising. However, it might be a coincidence and not be caused by human
activity at all. Yet, just as I should not expect proof that I am going to have a
car accident before taking out insurance, so replacing carbon fuels as a matter
of urgency is a sensible policy of mitigation. Replacement with the so-called
renewables (hydro, geothermal, wind, tidal, waves and solar) is simply not
sufficient, and biofuels and biomass release carbon into the atmosphere,
almost as much as fossil fuels [see Chapter 3].
Fired by political self-confidence, German policy is to cease use of carbon
and nuclear energies. Many other countries take a more scientific view and
consider that switching to nuclear energy is the best that can be done to
mitigate climate change. This policy has no technical drawback, but it has not
been popularly welcomed because nuclear energy and its radiation are seen as
frightening and dangerous. This causes people to close their ears and not
want to know more. However, this fear of radiation has no scientific basis.
The evidence needs to be explained clearly and understood widely, because
radiation phobia is the only obstacle to the provision of cheap carbon-free
energy [see Chapter 4, and also Chapter 2 of the book Radiation and Reason
(2006), see Selected References on page 279, SR3].
The truth is that we have made a major cultural error by shunning nuclear
technology. Big errors are the most persistent, and to get over them requires
concerted action by individuals and governments. So why is that not
happening? And how did we come to commit this error? To explain this, we
will have to turn a few more pages and question some commonly held
opinions [see Chapters 6, 9 and 10].
Safety and medical care
Does this mean that radiation is safe? And if so, how safe? How do we know
that for sure? The short answer is yes: radiation is safe and it has been saving
lives by diagnosing disease and curing cancer for over a century as pioneered
by Marie Curie. A radiation dose used in a medical scan is far higher than
encountered by the public in any nuclear accident, such as Chernobyl or
Fukushima. But how do you know? you will say. To feel safe and confident
about science, we should study and understand some parts ourselves and then
talk to friends and contacts to build up trust in the whole. Without such a
network of education and trust, in science as in other fields, mankind is
doomed. In brief, if you want to be safe and confident, you need to find out
what is going on.
4 Chapter 1: Many Misunderstandings
In the case of radiation we should look at the numbers that describe radiation
doses, and then ask more questions. During a course of radiotherapy
treatment the patient's tumour dies from a daily dose 200 times higher than a
typical diagnostic scan. In spite of receiving half this massive dose every day
for five or six weeks, nearby organs almost always survive. But safety is
always a compromise between engaging some risk to achieve a goal and
doing nothing, such as staying in bed. So it is true that radiotherapy may
have, perhaps, a 95% chance of curing an existing cancer, but a 5% chance of
starting a new one. Only by looking at the evidence and understanding what
radiation does, can real safety, and the feeling of confidence that goes with it,
be achieved [see Chapter 3, and Illustration 2 described further in Chapter 9].
Illustration 2: A graphical comparison of monthly radiation doses,
shown as the area of circles [more details on page 227, Chapter 9]:
•Red circle, the dose to a tumour treated by radiotherapy;
•Yellow circle, a recoverable dose to healthy tissue near to a
treated tumour;
•Green circle, a dose with 100% safety record;
•Solid black dot, a safety limit recommended by typical current
regulations.
(Green circle and black dot are also shown in magnified view to make
the black dot more clearly visible).
Nuclear is for Life. A Cultural Revolution. 5
Illustration 3: The final confrontation with the Environmental Anti
Fire Party in prehistoric times, perhaps.
Illustration 4: Picture. Shopping bag with simple sensible advice
about UV radiation for families.
6 Chapter 1: Many Misunderstandings
Hundreds of thousands of years ago, some say a million, man had the bright
idea of bringing fire into the home. This was not at all safe, but the benefit to
his standard of living with hot meals and warm accommodation quickly out-
weighed the risks. The choices of fire then and nuclear today are similar,
except the risks are very much smaller for nuclear than for fire. In both cases
education is key [see Chapter 2].
An example of the need for education about the physical world is protection
against UV radiation in sunshine. Parents are given simple advice about how
to teach their children to avoid sunburn and resulting skin cancer in later life.
As an agent that can damage living cells, UV is much more intense but less
damaging than X-rays [see Chapter 5]. But the net effect is similar: early cell
death (sun burn) or later cancer (skin cancer). These cannot be compared
quantitatively with the effects of nuclear radiation. However, although cancer
from UV is common and cancer from nuclear radiation is extremely rare,
public concern is the reverse.
At Fukushima there were no casualties from radiation [1] and the doses were
so low that there will be none, even in the next 50 years, even among the
workers at the plant [see the article SR8]. At Chernobyl radiation-related
deaths were limited to 15 fatal cases of child thyroid cancer and 28 workers
who fought the initial fire and died over the subsequent few weeks. At
Fukushima many casualties were caused by forced evacuation and fear, not
radiation. There were similar casualties at Chernobyl including several
thousand unnecessary induced abortions performed far away, simply out of
panic. Meanwhile the wildlife at Chernobyl today is thriving now that the
humans have gone: this has been captured in several charming videos [see
Chapters 2 and 3, and SR7].
Simple scientific pictures and the multiplication of some numbers show why
nuclear energy is a million times more powerful than chemical energy.
However, this energy source is so effectively hidden that its existence was not
even suspected until the final years of the nineteenth century. But that still
leaves open the question: What happens on the rare occasions that human
tissue is actually exposed to nuclear radiation? [See Chapters 7 and 8.]
It appears odd that the extreme power of nuclear radiation should have so
little effect on life, given that this is so very frail. We shall see that the answer
is that the whole purpose of life has been to survive in the Earth environment,
where ionising radiation and oxygen are the two most powerful physical
agents to threaten living cells. Providing this protection is what life does –
you could even argue that is all that it does, apart from an occasional battle
with other cells and viruses. Each element of life's structure is designed to
survive these two threats: eating, breathing, sexual reproduction, the partition
of life into autonomous individual organisms and the structure of those
Nuclear is for Life. A Cultural Revolution. 7
organisms as a myriad of autonomous reproducible cells. In some 3,000
million years of evolution it has perfected this protection, and a study of
modern radiobiology reveals some of the mechanics of how cells cope with
attacks by oxygen and radiation through strategies of repair, replacement,
adaptation and stockpiling of resources. This leaves any protection offered by
bureaucratic regulation way behind by comparison. People sometimes worry
about the effect of the radiation dose they receive in medical treatment, as
also they do about Chernobyl, Fukushima and other accidents. Instead, they
should marvel at the extraordinary natural protection they receive, and then
welcome the benefits that radiation has brought to modern medicine and
health following the tradition introduced by Marie Curie [see Chapter 8].
Historical reasons for nuclear mistrust
The twentieth century was a turbulent time in history and perceptions were
distorted by existential fears, even among eminent scientists. However, these
can be seen more calmly now in a historical perspective [see Chapter 10].
During the Cold War, when there was great disquiet about radiation and the
nuclear arms race, instead of educating the public, the authorities attempted
to appease negative opinion by promising protection from radiation at wholly
unnecessarily low levels. This approach was not successful, especially when
accidents occurred in which public panic, not radiation risk to life, was the
result. The authorities, themselves misinformed, failed to appreciate that
safety and confidence are best established by education and trust, not rules
Illustration 5: The natural protection of life provided by slow evolution wins
easily against recent regulations, as illustrated by Aesop's Fable of the Race
between the Tortoise and the Hare.
8 Chapter 1: Many Misunderstandings
and regulations [see Chapter 11].
Illustration 6: Picture of banknotes. Independent thinkers like Marie
Curie, Charles Darwin, Florence Nightingale and Adam Smith found
the right answers without committees and achieved acceptance. In
society today they symbolise trust, even on banknotes. We should
follow their example when considering how to reach the public on
matters like nuclear radiation.
Illustration 7: The legend of King Canute and his sycophantic
followers who believed he could do anything, but did not think for
themselves. So he had his throne placed on the seashore, and the
commanded the tide to go back, which it failed to do, much to the
surprise of his court. Science and nature do not obey regulations or
the commands of authority. It is better that at least some people in
society study and reach their own independent conclusions.
Nuclear is for Life. A Cultural Revolution. 9
Education, authority and confidence in society
Like nuclear power, currency needs popular trust and support, and banks
achieve this by enlisting pictures of famous figures, many of whom
contributed much more to science than to banking. They were broad
individual thinkers, not specialist experts or committee members, and we
should follow the way in which they won public support. Certainly we should
not believe everything we hear from uncritical popular chatter in the way the
followers of King Canute did [see Chapter 9].
With proper education and training, the general population is well capable of
acting rapidly and intelligently when faced with an accident. The immediate
response of the Japanese people to the earthquake and tsunami of March 2011
is a good example of what can be achieved. In such a situation in Japan
everyone knows what to do without asking authority. Because of their quick
action, the death toll from the tsunami was much smaller than it would have
been otherwise. With practice and study in school from an early age,
confidence and trust are established, ready for when a real disaster occurs, as
it did when the earthquake and tsunami hit. However, faced with an accident
that was not a disaster, but about which they were totally ignorant – the
nuclear accident – they could only look to authority, which gave no guidance,
being as ill prepared as everyone else. Fanned by the world press a wave of
distrust in authority and science then quickly followed [see Chapter 3].
Waste, cost and vested interests
Illustration 8: Symbols of waste
a) A radiation hazard symbol for nuclear waste.
b) A symbol of personal human waste.
But which waste is linked to the greater danger – that is, kills more
people annually?
10 Chapter 1: Many Misunderstandings
In the popular press it is widely supposed that there is a problem with nuclear
waste. If fully burnt, nuclear fuel produces about a million times more energy
per kg. than carbon fuels, and that means there is very little fuel and so very
little waste. It is mostly solid and can be recycled to get closer to complete
burn up. After a few years when it has cooled, the residue can be solidified in
glass and concrete which can be buried for the few hundred years needed for
its excess radioactivity to die away. Of course, if society wants to waste good
money by making extraordinarily elaborate provision, there is no shortage of
contractors who would be happy to step up to give the waste the
Tutankhamen burial treatment, a large long-term deep and impregnable
geological storage. At present nuclear energy is simply burdened by the
prospect of what this would eventually cost and the provision that has to be
made. This should not be the case.
But why pay so much? Unlike the waste from carbon fuel energy production
or the personal waste of humans, there has been no known loss of life from
civil nuclear waste. Discharge of human waste into the environment is the
cause of a million deaths per year by disease; and the open discharge into the
atmosphere of carbon dioxide and the other pollutants that accompany use of
carbon fuels of any kind is no less harmful [see Chapters 3 and 9].
Nuclear energy is thought to be expensive, but where does the money go?
Most of it goes, directly or indirectly, in salaries. So why does it take so many
people so long to design, build and run a nuclear power station? Because it
has to be safe! Indeed it does have to be stable in operation – which
Chernobyl was not. But at least half of the man-hours, half of the workforce,
is employed engaging with super-safe regulations, planning the
Illustration 9: Diagram of cannisters of a size to show the mass of
different waste produced per person per day in the UK
Nuclear is for Life. A Cultural Revolution. 11
decommissioning, checking workers in and out of secure areas for risks that
have been grossly over-estimated. The consumer and tax payer have an
interest in exposing this gross over-provision, but they do not understand.
Part of the problem is suggested in Illustration 10. However, the cartoon does
not refer to the nuclear industry itself whose ability to construct new plant
has been priced and regulated out of the market without good reason.
Countries less in thrall to regulators are able to invest for their future. They
will become increasingly competitive and will come to dominate the market
for the production of energy and the construction of plant. Decision makers in
western countries should appreciate that the current regulatory strangulation
is economically dangerous [see Chapter 12].
The task ahead
In the Cold War period people demanded safety from the threat of nuclear
radiation, but were given regulations instead. This was delivered wrapped in
pseudo-science and tied with legal knots. Blessed by committees of the
United Nations and enshrined in national laws around the world, these
restraints make it hard for the nuclear industry to make any progress towards
construction of the new plant required. So legislators have urgent work to do,
to release the nuclear industry from its straight-jacket.
On the professional side the pseudo-science, named LNT (Linear No-
Threshold), has to be repudiated, just as the epicycles of Ptolemy were
discarded to make way for the new understanding of planetary motion.
Fortunately, the evidence against LNT is easier to understand than the
Illustration 10: The interests of some parties are well served by the
inflated costs of unscientific levels of nuclear safety, although neither
the public nor the environment benefits at all
12 Chapter 1: Many Misunderstandings
dynamics of the solar system. Simply put, LNT says that all radiation doses
are harmful, however small, and that their effect is cumulative. The result is a
policy for radiation safety (sometimes called Radiological Safety) that
requires that all radiation exposures be kept As Low As Reasonably
Achievable (ALARA), which in practice means within a small fraction of
naturally occurring levels. This is unrelated to any risk, but comes from a
political wish to say that the effects of radiation have been minimised.
LNT assumes that the damage to cells increases steadily with the radiation
dose. This is a correct picture of the immediate impact of radiation, but the
effect of subsequent biological reaction is to repair this damage within a few
hours or days, unless the dose in that time is very high indeed [see Chapter
8]. The upshot is that the effect of radiation does not build up, and small or
moderate doses have no lasting effect at all, like modest exposure to bright
sunshine. Current regulations follow guidance given by the UNSCEAR
committee (United Nations Scientific Committee for the Effects of Atomic
Radiation) that denies the effect of this evolved biological reaction, although
this was fully described by a unanimous and critical French joint report of the
Académie des Sciences (Paris) and the Académie Nationale de Médecine in
2004 [see Chapters 4 and 8].
Safety regulations based on ALARA are not fit for purpose, and are
dangerous to the economy, the environment and to life and limb. For
example, they can frighten patients into refusing treatment that would benefit
their health. In the Fukushima region they have discouraged Japanese parents
from letting their children go outside in the fresh air to play. The increased
mortality of needlessly evacuated old people there shows how these safety
regulations can lead to death. The stacks of top-soil removed from fields,
now denuded and infertile, show a sad pictorial example of the destruction
Illustration 11: A photograph of contaminated top-soil, all bagged up
and waiting in vain for somewhere to go. [Iitate, Japan, Dec. 2013]
Nuclear is for Life. A Cultural Revolution. 13
that unthinking fear can achieve [see Illustration 11 and Chapter 2].
Of course, the safety of radiation is important, but new regulations should be
based on the threshold for radiation dose rates that can be shown to cause
damage to health: there is no shortage of agreed data from the accidents that
have occurred, and also from a century of experience of clinical medicine.
The latter is particularly appropriate as the general public receive such
treatment and are aware that it is beneficial, even though the dose rates are
high by any standard.
A justifiable radiation safety threshold should be set as high as to do no harm,
or As High As Relatively Safe (AHARS). A comparison between:
•the ALARA safety standard monthly dose;
•the dose per month experienced by the public in a radiation clinic;
•a suggested safe conservative monthly limit;
is made clearer, when represented by the areas of circles in Illustration 2 on
page 4. The threshold, shown as the small green circle, is about the same as
that set internationally in 1934, but is about 1,000 times the ALARA level,
shown as the area of the small black dot that may only be visible on the
expanded scale. That is the factor by which current regulations have typically
exaggerated any genuine radiation risk. However, it is right that these ideas
should be explored and checked in considerably more detail in the chapters
that follow. In particular, possible values for thresholds and the evidence
behind them are discussed in Chapter 9.
Note on Chapter 1
1) In October 2015 a report circulated in the media referring to a Fukushima worker
who contracted leukaemia. Such random cases are expected in any population and
no causal link was suggested. However, under Japanese law because the worker
had received a small dose of 5 mSv he was automatically entitled to
compensation. This was misinterpreted by the media.
Nuclear is for Life. A Cultural Revolution 15
Chapter 2: Intelligence as an Aid to
Survival
The most difficult subjects can be explained to the most slow witted
man if he has not formed any idea of them already; but the simplest
thing cannot be made clear to the most intelligent man if he is firmly
persuaded that he knows already, without a shadow of doubt, what is
laid before him.
Leo Tolstoy
It is difficult to get a man to understand something when his salary
depends on his not understanding it.
Upton Sinclair
Facing the problems of civilisation
Democracy and personal understanding 15
Fear of traumatic change 17
Learning from fable and science
Personal and public opinion 18
Science before Earth began 18
Fire in the home 19
Nuclear safety misjudged
The news from Fukushima Daiichi 21
Matching evidence and expectations 23
Pseudo-sciences and wishful thinking 24
Fear of nuclear energy
A zeitgeist reconsidered 26
Notes on Chapter 2 27
Facing the problems of civilisation
Democracy and personal understanding
Can the planet support ten billion inhabitants? It almost certainly can, but
severe conditions will be imposed by the environment, science, education and
human behaviour.
The impact of mankind on the environment is among the world's most
16 Chapter 2: Intelligence as an Aid to Survival
pressing problems. It is time to ask questions: do we really understand
nature? How can we use nature with minimal effect on its sustainability?
Should we just carry on without re-examining earlier decisions and attitudes?
There are facts that nobody can deny, even though some still question the
causation of climate change:
•the atmosphere is tiny, equal in mass to a layer of water just ten
metres thick around the world;
•the steadily increasing concentration of poly-atomic gases in the
atmosphere;
•the definite, if erratic, rise in temperatures and melting of ice sheets;
•the increasing consumption of energy that is essential to any socially
stable and expanding economy;
•a world population that increases with lengthening lifespans,
unmatched by falling birthrates.
It may be late to take sufficient control, but it is never too late to take stock of
the position and take action to reduce any serious consequences. Taking stock
must allow the possibility that attitudes to major items in our armoury are
misunderstood – that should include the historical view of the atomic nucleus
and what flows from it. This book is not about climate change but it is such a
stock taking.
Every child is taught from an early age that fire is dangerous. If the child fails
to get the message, the chances are that the physical pain of a small accident
will serve as a reminder, not easily forgotten. In the same way, each child is
trained to cope safely with human waste – potty training comes high and
early on the list of educational requirements. These are not options in human
society, but young children learn easily. As they grow older, they become
more selective about the information they absorb. This selection depends on
what they have already learned and accepted, and on new evidence of which
they become aware.
However, new evidence may conflict with what was previously understood
and then be dismissed out of hand – that is the easy way out. Alternatively,
the conflict must be examined – not a childish process, but one of ongoing
self-education. A readiness to re-examine opinions like this is essential to any
effective democracy because it allows views to flex as information changes.
But such re-examination of opinions depends on sufficient numbers of the
electorate being well informed, able to make up their own minds, and ready
to change their opinion when evidence indicates. But, if views are long
standing and get repeated uncritically, a democracy may be unable to change.
Instead, it becomes locked into a semi-permanent misapprehension that leads
Nuclear is for Life. A Cultural Revolution 17
to ill-advised decisions. Stability is only established when real information is
accepted and people are ready to learn afresh, but, as Tolstoy wrote in the
paragraph posted at the head of this chapter, this presents a high educational
challenge.
The task of this book is first to ask in straightforward terms why so many in
society have an aversion to nuclear science; then to explain to them the
balance of benefit and risk as it is known today. With the damage apparently
inflicted on the environment by carbon combustion – coal, oil, gas, biofuels
and biomass – the relevance of comparing nuclear energy to fire is clear.
Many people are reluctant to change their opinion even when faced with
evidence that contradicts it. Such rejection of scientific evidence is too easy,
especially when the reluctance is supported by a whole industry of experts –
from local safety officers to international lawyers – who have jobs with
careers and standing that depend on the status quo. The quotation by Upton
Sinclair at the head of the chapter makes the point.
Unfortunately, these are the very authorities that the press and politicians tend
to consult when they want advice and information. Such consultations are the
norm, since few people are prepared to stand up and say that they themselves
understand an issue sufficiently. In this way a pass the parcel culture of weak
responsibility, stabilised by a fear of litigation, discourages personal
judgement and leaves decisions in the hands of expert authorities who are
least likely to recommend change. We shall go behind such interests to look
at the evidence for what was previously claimed to be obvious and settled.
Fear of traumatic change
Deciding to change your opinion can bring an element of shock – an
embarrassment that may be avoided by postponing the decision. Visualise a
meeting on a very hot day at which a number of people are standing
nervously around a swimming pool waiting for someone to dip his toe and
announce to all that the water is acceptably warm. A dive into the water
would be refreshing in the heat, but the immediate cold shock might be
undignified in front of the others – so nobody jumps in. Everybody at the
pool sweats uncomfortably, denying themselves the refreshment of the cool
water. They remain prisoners of their indecision, unwilling to risk the cool
splash of change.
It can take leadership to be the first publicly to express a change of view.
Nevertheless, many of those previously active in campaigns against nuclear
technology, including leaders of the Greenpeace movement, have actually
switched their opinion of nuclear energy [1], in particular Mark Lynas, Patrick
Moore, Stephen Tindale, James Lovelock, Stewart Brand and others. These
are the exceptions. But how is it then possible to go further and encourage
18 Chapter 2: Intelligence as an Aid to Survival
others to change their views, many of whom who are still deeply
apprehensive of nuclear technology? Evidence is needed to account for how
received opinion has developed since World War II, and an exposition is
needed of the science and medicine involved.
Learning from fable and science
Personal and public opinion
What each of us, personally, knows of the world we inhabit is built on our
accumulated experiences and observations, and these we extend by thinking
and studying, based on our own learning. Together these form the basis of our
personal opinions – meaning that we are able to check and verify them
relatively easily. Ideally, this would be the basis of all that we acknowledge,
but in a practicable world, we also need to listen to the opinion of others in
order to engage with other questions and problems encountered in life. When
we seek advice from another in this way, we try to choose someone with
personal knowledge. Failing that we may have to follow a majority view. But
this can be a bad move if everyone else does the same. We would all know
what everyone else believes, but what passes for information is rootless,
giving rise to unstable opinion and a potential for panic. To avoid this, a few
people at least should actually understand a matter independently. This
should not be seen as a recipe for a class of experts or high priests who then
become motivated by their own group agenda when giving advice. Rather we
should call for such expertise to be filtered through the education of new and
younger minds so that ideas can be accepted or rejected by their unbiased
studies.
Traditionally children are brought up with fairy tales that encourage them to
keep their eyes and ears open and to acknowledge obvious truths. For
example, they learn that old people lose their youthful looks but they must
cope when their imagination raises a frightening question like Is the apparent
grandmother in reality a wicked wolf? This book asks whether nuclear power
is a similarly wicked wolf, which the popular imagination supposes with the
help of the press. We should look at the evidence. This story is set, not in a
dark and secret enemy research laboratory, nor in a frightening earth-bound
forest, but in the huge natural universe – a universe that is largely benign,
principally because we are creatures that have evolved to fit with it. Those
who fitted less easily are the ones that already died out, according to Darwin.
But the story continues – if we do not fit with our environment and look after
it, we too may die out.
Science before Earth began
Before humans, before Earth, before the matter of which Earth is composed,
radiation completely dominated everything in the universe. As the universe
Nuclear is for Life. A Cultural Revolution 19
cooled from its creation in the Big Bang 15.8 thousand million years ago, the
radiation subsided leaving clumps of matter to emerge as galaxies of stars.
With the exception of hydrogen, this matter was made of nuclear waste left
after an orgy of early-exploding stars that created all the chemical elements
we see around us today. Earth was formed some 4.5 thousand million years
ago, and not long after that the slow development of life began. Much later, a
mere million or so years ago, man appeared. Then, a few hundred years ago
man began to understand how he himself could engage the power of science,
culminating in his ability to work with radiation and generate energy from
nuclear matter.
Many speak as if nuclear energy and radiation were man-made, and perhaps
compare a decision to use it and its powerful influence to Adam and Eve
deciding to eat the forbidden fruit in the Garden of Eden. But man did not
make radiation or nuclear energy – it was nuclear radiation in the natural
world that was needed to make man, long before. Indeed it is the failure of so
many to eat the fruit of this knowledge that has lead to the sorry story of
Fukushima Daiichi – a tragedy of ignorance, a tangled web of
misunderstanding and undeserved distrust of which Shakespeare would have
been proud. The story deserves to be retold in a positive and properly
scientific light.
Fire in the home
Decisions about energy affect people's lives and many have strongly held
opinions. But those opinions, whether about conventional fuels or nuclear,
have to be confronted with evidence, and the right way forward has to be
argued out. We may imagine how mankind fared in earlier times when faced
by another question at least as momentous as a decision to adopt nuclear
energy and to phase out the burning of carbon fuels.
Perhaps many hundred thousand years ago there was consternation among
the more conservative environmentalists of the day when radical innovators
started building hearths and bringing fire into the home. Obviously, most
people were frightened – everyone knows the dangers that come when you
start messing with fire – and choosing to do so at home must have seemed
irresponsible. The readiness with which fire can catch and spread has been
the cause of countless fatal accidents – it is a thermal chain reaction that is
difficult to put out. Even today, in spite of regulation, instruction and ever-
ready emergency services, fire remains a threat with a substantial annual
death toll. When animals see or sense fire, experience tells them to run away,
and collectively they are apt to panic. Man usually does the same, but at some
point in the early Stone Age – nobody knows quite when – he made a
momentous stride for civilisation: overcoming his natural fear of fire he
stopped, used his brain and studied the problem. He realised that on balance
20 Chapter 2: Intelligence as an Aid to Survival
the benefits of fire outweigh its dangers, provided personal education and
training is given to everybody, children included. It was a turning point that
gave humans immediate supremacy over all other beings. Civilisation could
not have developed without fire, and we would probably have remained
animals with a limited population and a short and brutish life if we had
heeded the advice of the environmentalists of those days pictured in
Illustration 3 on page 5.
Initially, no doubt, few shared this enthusiasm, and we may imagine some
noisy demonstrations with members of the Anti-Fire Party opposing the new
technology because, as they said, everybody knew that fire was dangerous
and they had tales of death and destruction to back their case. But in the end
they were over-ruled, and the lure of hot cooked food and warm dry
accommodation won the day. Perhaps it did not happen quite like that –
perhaps the protesters, afflicted by poor health and inadequate diet, just died
of cold and hunger, being uncompetitive with those who embraced the new
technology. Anyway, every generation of children to this day has to learn
respect for fire, often through the experience of a hot stove and a few tears.
In fact, the advance was not just the introduction of fire into the home but the
power to think and act with confidence – to study and control the use of fire
and other sources of energy in the environment. As man used his brain and
learnt more, his confidence in his scientific studies grew, and cooperation and
trust in society at large grew with it. But such trust is fragile and is easily lost
or destroyed.
This process of learning has continued, and in the past century there have
been two important discoveries suggesting that the decision to use fire
liberally should be re-examined. Firstly, fire has consequences even more
dangerous than previously understood, namely the effect of its emissions on
the global environment [see Selected References on page 279, SR3 Chapter
2]; secondly, there is an alternative energy source to fire that does not have
the same drawbacks, neither the tendency to spread and multiply nor the
environmental impact. In addition it has more than a million times the energy
density of carbon-based combustion.
This alternative is nuclear technology, first made known to the public in a
sudden dreadful shock at the end of World War II with the bombing of
Hiroshima and Nagasaki. This negative experience was reinforced by the
political and military propaganda of the Cold War period. Notwithstanding
this, the public has benefited from nuclear technology for over a century
through its use firstly in clinical medicine to image the internal anatomy of
the human body and its functioning, and subsequently to diagnose diseases
and cure cancers without surgery. Today the question is whether nuclear
technology is really as dangerous as the public has been encouraged to
Nuclear is for Life. A Cultural Revolution 21
believe. Fire is welcomed in spite of its obvious dangers. Should nuclear
energy be rejected? Or should it be accepted as the least bad option to save
the endangered climate? Or even, should it be welcomed because nuclear
energy is safer than fire and only dangerous under quite exceptional
conditions? Whether to use nuclear technology is the new Promethean
question. It is a decision as important as the domestication of fire.
Nuclear safety misjudged
The news from Fukushima Daiichi
The accident at Fukushima has shown the answer rather clearly: nuclear
power is safe to use. But this has not been appreciated. Furthermore, the
relevant public education and training has not been given, and the guidance
given by the authorities, both national and international, has been based on
seriously mistaken science. As a result the costs of nuclear energy and its
safety have been completely misrepresented.
Later chapters provide discussion and the evidence that nuclear power is safe.
Based on this evidence, the authorities from the United Nations down should
be urged to reconsider their advice, so that the wider public can make up their
own minds. In democracies at least, politicians are likely to continue to
appease the fear of radiation and make decisions that lead to a lack of
economic competitiveness and environmental damage, locally and globally.
However, once public opinion is better informed, leaders will see that there
are votes in pursuing the course for the common good.
The press saw the accident of March 2011 as the start of a new era. For the
first time since the man-made nuclear age began, the media were ready and
present at the scene of a nuclear accident with their cameras running and
ready to stream 24-hour news. They captured pictures of chemical
explosions; they speculated about the significance of leaks of gases and water
carrying radioactive waste material; making little comment on the deaths of
more than 18,800 people from the tsunami, they preferred to keep media
attention focussed exclusively on the big story – and they believed that was
the nuclear one. Every day for weeks, then months and years, they described
radiation escapes and radiation doses said to be high. But nothing happened –
nobody was hurt by radiation or radioactivity. Unable to accept or appreciate
that the script was not developing as they had expected, the journalists and
reporters continued to rephrase the stories of high radiation readings and
escaping radioactivity without being able to show why this mattered, except
that it frightened people around the world who then bought their news stories.
On previous occasions when the press had reported from the scene for the
first time, the consequences were far reaching. For instance, the open
22 Chapter 2: Intelligence as an Aid to Survival
reporting of the Vietnam War with its dramatic pictures and true accounts
showed it to be genuinely shocking, and this contributed to turning public
opinion against the war, at home in the United States and elsewhere. But
never before Fukushima had the story been nuclear. Media interest in getting
real nuclear pictures had never been satisfied in the 65 years since the
bombing of Hiroshima and Nagasaki. The 1957 Windscale Fire was much
smaller than Fukushima and not openly reported at the time; the Three Mile
Island accident was contained and produced neither pictures nor casualties;
Chernobyl was inaccessible, hidden behind the Soviet veil that crumbled
shortly thereafter. So for the first few days at Fukushima, media reports felt
able to indulge in nuclear superlatives, for the first time after many years of
waiting. But apart from the fear maintained by the reports themselves, it was
not like that. Lacking a ready script, the media started to scratch around for a
story. Popular reports urged the public to blame the operating company,
TEPCO (Tokyo Electric Power Company), and the Japanese government for
lying, secrecy and bad management – they could hardly blame them for
injury and manslaughter because there had been none. Few, it seemed, looked
at what had really happened, or rather had not happened. Around the world
the initial collective panic spread, unrestrained, in an atmosphere of global
ignorance. Politicians and others drew up instant national policy reactions
without fundamental reappraisal, and this was reflected too in official
international reports, although these took many months, even years, to
appear. But did anyone dare to ask the big question? Was anyone in danger
from the radioactivity and its radiation?
All the nuclear power plants in Japan were shut down and put into stand-by.
This resulted in electricity shortages and then massive economic and
environmental costs, as substitute fossil fuel was imported and burnt. Over
100,000 people were evacuated from the region and many more left
voluntarily. Food was condemned by regulation and more rejected by market
forces, this in a relatively poor agricultural region where farming businesses
were quite fragile anyway. Children were encouraged not to play outside, old
people were moved from their sheltered accommodation, often with fatal
results. The population showed all the symptoms of extreme social stress –
bed-wetting, suicides, family break-up, alcohol dependence. No explanation
was given to the local people of what was happening to them. Local
discussion degenerated into arguments about blame and compensation.
Inevitably those who moved away from the region were the more affluent,
leaving an immobile residual population without the youth and ability needed
for a viable community. At great expense, work began to remove topsoil, said
to be significantly contaminated, from fields in the evacuated regions. But
this policy was not thought through and had negative consequences:
•Topsoil removal was found to reduce the radioactivity of the fields by
Nuclear is for Life. A Cultural Revolution 23
50% at most.
•Fields lost much of their fertility without their topsoil.
•The forests and steeper rocky regions above the fields could not be
included in the work, but these covered a wide area, seen in the
background in Illustration 11 on page 12.
It is difficult to see how this expensive work makes any sense. Later chapters
will show why radioactivity in the region, as shown in Illustration 13 on page
44, is far from dangerous, so that a 50% reduction does not make a cost-
effective difference. Teaching the local population about radiation and why
they should genuinely have no worries would be a better investment, but
obviously that would take longer. But for a start they would get some
immediate hope and encouragement from viewing the professional videos
showing wildlife thriving at Chernobyl today [SR7].
Around the world many other nations also panicked. Some withdrew their
nationals from Tokyo, even from Japan, and introduced plans to shut down
their nuclear plants and rely on renewables, which in practice increased their
consumption of carbon. Eminent international bodies met and responded to
popular demands for increased nuclear safety. Mandatory standards were
raised, large numbers of people eagerly accepted new jobs in nuclear safety,
and the quoted capital cost of nuclear power stations and the electricity they
produce rose as a result. These funds and jobs became available as a result of
the ballyhoo, but few analysed what had actually happened and whether it
warranted such a reaction.
In later chapters we explore the worldwide cultural misunderstanding, with
its roots going back 70 years, that lies behind this reaction to the accident,
why it happened and what should now be done about it. Science policy
blunders have been made before, but this one has wider consequences
because it threatens both the world economy and, at the same time, the best
prospect of stabilising the planet's environment for the benefit of all.
Matching evidence and expectations
What happened at Fukushima Daiichi was not what was expected. The
supposed terrible tragedy seemed not to match the evidence. There are only
two possibilities: either it was simply wrong to expect that such radiation
would cause physical harm to the population; or the effects of the radiation
will turn out to be much worse in the end than the results have so far
suggested. These possibilities are investigated here.
For any experience that complies with common sense our expectations
beforehand should match what happens. If this is so, our confidence builds.
Otherwise we must admit that we have got something wrong and it is a
24 Chapter 2: Intelligence as an Aid to Survival
matter of back to the drawing board to understand how we were wrong. That
is the scientific method. We could get mathematical at this point by
expressing confidence as betting odds and work out what how expectations
should change in the light of new information. Fortunately this can usually be
avoided because the conclusion is plain to see. In particular, if the new
information completely disagrees with the prior expectation, mathematics
should not be used to hide the blatant inconsistency.
So we need to examine our expectations. If something is obviously at odds,
we should not accept that some sophisticated statistical analysis or
pronouncement from an eminent committee can avoid it. Such a situation is
described in the story of the Emperor's New Clothes by Hans Christian
Andersen. If the Emperor is wearing no clothes, then no pronouncement from
his officially appointed international tailors carries any weight, and common
sense is sufficient to see that. The radiation dangers experienced by the
people of Fukushima are like the Emperor's clothes – they are not there! The
situation must be reviewed and resolved.
Pseudo-sciences and wishful thinking
By examining other major nuclear accidents, particularly Chernobyl and the
one at Goiania, it becomes clear that no incidence of late cancer or other
mortality should be expected at Fukushima. So the predictions of disaster
were simply wrong. We will need to examine where these came from. The
story will go back many decades to the birth of a pseudo-science called the
Linear No-Threshold Hypothesis (LNT). It is described as a pseudo-science
because it is not based on observation but on a history of ideas, fears and
human emotions, quite real in their own terms but not scientific. LNT joins
other pseudo-sciences, such as alchemy and astrology, that seemed
interesting in their day but were finally brought down by conflicting
evidence. How do pseudo-sciences come to be accepted in spite of their
erroneous basis? How did alchemy and astrology get their limited
acceptance, and did LNT become accepted by authority following a similar
route?
Science requires care and attention to detail if wrong turns are to be avoided.
Navigation offers a practical example. A boat that sails from A to B on a map
on a steady course will arrive happily if the voyage is less than a few hundred
miles – that is called plane sailing, as it would seem no different if the Earth
were a flat plane [2]. However if the voyage is longer, plane sailing does not
offer the most direct route because of the curvature of the Earth: for this, the
boat should steer on a great circle with a slowly changing course relative to
the points of the compass. That may not be clear to the non scientist, but it
shows how a proper understanding of the problem is needed if mistakes are
not to be made. Likewise, on the safety of radiation, having found that we
Nuclear is for Life. A Cultural Revolution 25
were wrong, we should develop a deeper understanding so that we can make
better decisions.
Astronomy impressed everyone in the ancient world, as it does also today. It
began by describing events of exceptional regularity: the rising of stars, Sun
and Moon; their links to tides and seasons; astronomical measurements for
navigation with ever greater accuracy; the movement of the planets; finally
the prediction of eclipses. The authorities of the ancient world were naturally
in awe of the astronomer. No doubt they took the priest of this power into
their confidence and asked his advice. The astronomer would be pressed on
many urgent questions about which he was certain and others about which he
was quite ignorant. But could he refuse the offer of research facilities and
substantial grants? Perhaps he only had to guess whether the King would
have a son. It is not surprising if at an incautious moment he accepted the
research grant money on offer and agreed to use his astronomical powers to
study the probability of the birth of a male heir. If he got the prediction
wrong, the result might be fatal for him, but think of the grant and the
studentships he said to himself. In this way the pseudo-science of astrology
was born.
Predicting the weather was uphill work in ancient times, and it still is today.
At that time, everyone's lives depended on what they could grow, given the
weather, and what they could make with their tools of wood, stone and metal.
The contribution of metalwork to the economic competitiveness of early
civilisations was crucial, and the ability of their geologists and chemists to
extract metal by heating and treating rocks was simply magic to the majority
of the population. While they learnt how to produce base metals from raw
minerals, everyone dreamt of producing precious silver and gold by
extending the magic. Good research money was always on offer to any
charlatan or fool unwise enough to offer to transmute base metals into gold.
The pseudo-science of alchemy was driven by greed and ambition, and
frustrated by true science. But that did not stop people indulging, and many
legends recount the fate of those who used fair means and foul in their pursuit
of riches in this way. Alchemy's credibility depends on gullibility and
ignorance, but, like astrology, its faulty appeal is exposed by education.
Does LNT provide another example of such a pseudo-science, this time
drawn from the mid twentieth century instead of the Middle Ages? LNT
seemingly justifies a fear of radiation, or radiophobia. This fear may be
genuine, but that does not mean that radiation is actually unsafe for low or
moderate exposures, and of course fear should not be seen as a sufficient
reason for proscriptive regulation. Those with a fear of the dark or of heights
(like the author) may be really frightened, but such phobias are not built on
science. It is dangerous and irresponsible to inflict on others the false
rationalisation of such subjective phobias, however unbearable they may
26 Chapter 2: Intelligence as an Aid to Survival
seem personally. Forbidding anyone from going out in the dark or climbing
ladders would be wrong, unless there were solid statistical accident data to
justify it. Any such restriction would reduce productivity and
competitiveness. More generally, our practical superiority over other animals
depends on an ability to face any apparent dangers objectively.
Fear of nuclear energy
A zeitgeist reconsidered
Every age has its cultural spirit or zeitgeist. Some are beneficial while others
are injurious. Religious ones may hold sway in a region, sometimes for many
centuries. Secular ones can be geographical too, but seldom last so long. To
adherents, the ideas may seem self evident, that is until they are found
wanting and the false confidence they offer implodes. The persistence of
some is stabilised for a time by hate or fear that suppresses study and open
discussion. In this way deep examination is effectively prevented for
everybody in society, except for a few technical priests. Ideas may appear to
be isolated by education if people are made to feel that understanding is
beyond them. Similarly the power of voodoo or the curse of a witch doctor
may sustain a primitive belief by a collective intimidation that allows no
questions.
In modern times, general improvements in education have prevented or
suppressed many instances of false or malignant fashions. Among those that
have persisted, few have exerted a widespread inhibiting influence as strong
as radiation phobia – the reaction to matters invoking the words nuclear and
radiation. In the wake of news of the nuclear bombs of 1945 came a
prescribed litany of nuclear awe to which all assented, and still do. But in the
twenty-first century the impact of carbon fuels on the environment has
brought a fresh need to exorcise public fears of nuclear technology. A simple
transparent appreciation of radiation is required to replace the rationalisation
based on flawed science that has been used in the past to underscore radiation
phobia.
The supply of energy and the ability to use it have been responsible for
maintaining life on Earth from its beginning well over 3,000 million years
ago. In the modern human era this has lead to large populations living under
improving conditions. Until recent centuries change was dictated through
natural selection, a gentle-sounding description of death, but which
frequently occurred on a large scale. Today the ability of humans to study and
plan provides a more welcome way to bring about change, although to be
effective this depends on the education and understanding of decision makers
– in a democracy, the electorate and the politicians answerable to them.
Nuclear is for Life. A Cultural Revolution 27
Popular opinion about energy is still heavily influenced by fear of nuclear
energy. This threatens to restrict not only the supply of energy, but also stable
economic growth, food and clean water for a population living in a fragile
climate. The remarkable accident at Fukushima challenges this fear and calls
for a re-examination of nuclear technology using a coherent modern scientific
understanding of the physical, biological, medical, and social issues involved,
expressed in a form understandable to a broad readership.
Trust in science is properly established by successful numerical prediction
and measurement. Its explanation can be supported by pictorial diagrams and
graphical descriptions that help make the truth intuitively obvious. The ability
to draw or visualise a scientific result is as important to creating confidence
for the scientist as it is for everybody else. So the following chapters use
common sense, diagrams and pictures as well as a few numbers to help in
reaching conclusions. Sometimes those numbers may be accurate and carry
only a small uncertainty. Just as often the uncertainty may be quite large, but
the conclusion will still be unavoidable if the alternative differs by a factor of
hundreds or thousands. However, if all numerical comparisons are ignored,
any discussions may degenerate into heated debate between parties unable to
express their conclusions in clear numerical terms, as is often to be found in
the media.
Notes on Chapter 2
1Statements of environmental and other academic support for German nuclear
power (2014) http://maxatomstrom.de/umweltschuetzer-und-wissenschaftler/
2This is often described as plain sailing, a spelling that suggests a
misunderstanding. The Oxford English Dictionary accepts both spellings.
Nuclear is for Life. A Cultural Revolution 29
Chapter 3: Rules, Evidence and Trust
The great enemy of the truth is very often not the lie – deliberate,
contrived and dishonest – but the myth – persistent, persuasive and
unrealistic. Too often we hold fast to the cliches of our forebears. We
subject all facts to a prefabricated set of interpretations. We enjoy the
comfort of opinion without the discomfort of thought.
John Fitzgerald Kennedy
Energy for civilisation
Natural rules of life 30
Energy and other needs 31
Solution without carbon dioxide emission 32
Sources of energy 33
Stored energy and its safety 33
Nuclear energy 34
Two soluble problems of power from nuclear fission 35
Widespread myths that should be contested 35
What happened at Fukushima Daiichi in 2011
Japan's preparation for the earthquake 36
Reactor shutdown and decay heat 37
Tsunami arrival 38
Reactor damage by tsunami 39
The chemical story 39
Radioactivity released into the air 40
Re-criticality suppressed 40
Radioactivity released into the water 41
Spent fuel ponds 41
Public trust in radiation
Ignorance and lack of plan 42
The fallacy of absolute safety and the loss of trust 42
Impact on public health 44
Protective suits that frighten or impress 45
Loss of life 46
Caution that harms people but protects authority
Psychological disaster at Fukushima 46
Symbols of hazard 48
30 Chapter 3: Rules, Evidence and Trust
Evacuation, clean up and compensation 48
Fear of artificial radiation 49
Questions about the danger of internal radioactivity 50
Radiation safety is inter-disciplinary 51
Fear of the radiation from a CT scan 52
Wastes, costs and conflicting interests
Comparison of waste products 53
Nuclear waste 54
The cost of nuclear energy 54
The scale of a nuclear reactor 56
Notes on Chapter 3 57
Energy for civilisation
Natural rules of life
Many questions are only as interesting as their answers. Such a question is:
What is the purpose of life? We are not talking just about human life here, but
all life, conscious and unconscious, down to the simplest cell. How does life
in all its manifestations actually go about living? We may observe how it is
intensely concerned with relationships and competition – personal friends
and communal enemies, infections and antibodies, political parties and
military campaigns. The Darwinian answer to the first question is to survive –
and more certainly and prolifically than the competition.
But there are rules. Much as the individual may strive to survive personally,
that is not the main aim of life in general. The first rule is that all individuals
die – survival is only for their progeny. Any personal belief in the sanctity of
life that we may harbour is not shared by nature. Frequently, countless
individuals are sacrificed in the carelessly inefficient process of finding
Darwin's fittest samples. Similar carnage occurs in the competition amongst
cells in the microscopic world. Nature offers sanctuary to very few, and
continuing life to none.
So the First Rule of Life is that it is limited. Death is certain and there are no
exceptions.
Individuals arriving on planet Earth come with nothing except their genes,
and when they die they leave behind everything they have built – money,
status, personality, education. These may have been useful within their
lifespan, but no more. That means the worth of these is far less than the genes
left to posterity. So the Second Rule of Life is that you travel light – you
bring nothing in when you are born and take nothing with you when you die.
Nuclear is for Life. A Cultural Revolution 31
There are no exceptions to this rule either.
Life as we know it is confined to the thin shell of the atmosphere at the
surface of the Earth – so no wonder it is so easy to pollute. Expeditions from
the surface of Earth have been few, limited in range and immensely energy
intensive. Attempts to find life elsewhere in the universe have shown no
success and, anyway, it is hard to see how life elsewhere could be of much
benefit to us. So we should expect to be limited to a small, overpopulated and
increasingly polluted planet, effectively alone in the universe. What do we
need while we are here? Life needs energy, and energy has a rule: energy is
conserved. You cannot make energy. That is a rule of physics. As with the
two rules of life, there are no exceptions to the energy rule and its
consequences are far reaching.
Energy and other needs
It is relatively easy to discuss past problems – we may speculate on those of
the present day, but we are simply unaware of those of tomorrow. It is hard
work seeing current events in perspective, so the best discussion of future
problems we can offer is to start with those of today that currently seem to
have no prospect of adequate solution. In 2015 that list includes:
•Climate Change. The scientific evidence is now widely accepted [1],
although the effect of dynamic exchanges between the small mass of
the atmosphere and the large mass of the oceans is still uncertain,
quantitatively. Exceptional weather and melting ice sheets have
influenced public views. Compared with even a year ago, noticeably
fewer sceptical voices are now heard. And then there is the role of
methane and its release in large quantities from a warming Arctic; the
public do not seem to be generally aware of this yet.
•Socio-economic instability. Following the misinterpreted Arab
Spring of 2011 instability has spread to a broad swathe of countries.
Lawlessness seems to have be come endemic in some regions, and
the world powers are less willing, financially and politically, to
intervene. Perhaps that is because they have become less confident of
their own stability than they were in the past. Fracture, if not
collapse, of many regimes seems more likely than at any time in the
past 50 years.
•Food, water and population. Malthus, an English cleric, famously
wrote in 1798 that the world population must necessarily be limited
by the means of subsistence, and would be suppressed by misery and
vice. His predictions have been delayed in their effect, but their logic
remains. Although today birthrates fall as societies develop, the
demand for resources rises with an ageing and risk-averse middle
32 Chapter 3: Rules, Evidence and Trust
class. At the same time, societies with younger populations are
unable to satisfy ambitions for food and jobs. The pressures of
migration, exacerbated by changes in climate, are evident and likely
to trigger increasing conflict. Meanwhile, clean water supplies
remain critical, and extra food relies on aid that is inevitably limited.
•The threat of epidemic. The evidence from the Ebola outbreak of
2014 shows that the world is not well prepared and reacts slowly. If
Ebola had been a more contagious disease the worldwide escalation
would have been severe.
If we are not to find ourselves marooned on a shrinking ice-flow like a polar
bear, so to speak, we need to find solutions to these problems.
Solution without carbon dioxide emission
Natural forces shape the future, but so too does human organisation,
nationally and internationally. Is it possible that human society, using its
collective intelligence and education, might achieve some acceptable degree
of equilibrium, at least in the provision of energy?
Atmospheric oxygen and the combustible materials on Earth, including those
that are buried as coal, oil and gas, together form an energy store, a kind of
battery. Currently this store is being discharged at an ever increasing rate by
human activity, directly and indirectly. Human life itself makes a small
contribution by taking in food and oxygen, and releasing carbon dioxide, so
too do animals, both wild and the domestic ones kept mostly as sources of
food. Although discharges from volcanoes and forest fires may be natural,
many other fires are man-made. So too are electricity generation, transport,
heating and other industrial activity that use carbon energy. In earlier decades
concern for the future of carbon energy was based on the limited supply of
fuel, but that has changed. Now the main concern is the effect on the climate
of the discharged carbon dioxide. Direct measurements of the concentrations
of greenhouse gases like carbon dioxide, taken anywhere in the world, show
how they are increasing every year, year on year. There are reasons,
dependent on the physics of these gases, to suppose that these increasing
concentrations should affect the Earth's climate [see Selected References on
page 279, SR3 Chapters 2-4].
Mankind needs a supply of energy to be available at all times of day and
night. Without it, conditions on Earth would not support a fraction of its
population today and its loss would involve death on a worldwide scale. Yet
the appetite for energy is too large for any available intermediate storage to
make a significant difference. So, it is the source of the energy that matters,
and this should not add significantly to pollution, or increase the likelihood of
global disease, war, climate instability, water shortage or starvation. But does
Nuclear is for Life. A Cultural Revolution 33
any available source meet these demanding requirements?
Sources of energy
The carbon fuels – oil, coal, gas and the various forms of biofuels – should
all be ruled out because of the carbon dioxide they release. Radiation from
the Sun gives solar energy, directly, but it also indirectly drives wind, wave
and hydro power. The gravity and motion of the Earth relative to Sun and
Moon is the energy source behind the tides. Another so-called renewable
energy source is heat from the inside the Earth. This originates from the
radioactive decay of elements scattered through the volume of the Earth. In
fact the output of radioactive heat per kg within the Earth is about equal to
the natural radioactive heat in the human body (see Chapter 7). In the Earth
this heat provides, not only geothermal energy, but also the thermal power for
the motion of the tectonic plates and thence earthquakes, tsunamis and
volcanoes. Geothermal power is particularly accessible in places at the edges
of tectonic plates, such as California, New Zealand and Yellowstone National
Park.
Often included in a list of so-called renewable energy sources are biomass
and biofuels. However this shows a strange lack of straight thinking. These
sources burn the vegetable matter created by natural photosynthesis, thereby
discharging the waste carbon dioxide straight back into the atmosphere.
Nature works hard to grow trees and other vegetable matter to reduce the
carbon dioxide in the atmosphere. This is something that man cannot do
himself on a large scale, but the use of biofuels and biomass simply discards
the benefits of this natural and successful carbon capture. Their combustion is
an amazingly short-sighted development, no better than the use of coal, oil or
gas. Furthermore, their production often displaces the growing of food on
large areas of agricultural land, and, what is worse, in many parts of the
world, forest is destroyed for the purpose.
Stored energy and its safety
Popular discussions of energy supply often conclude that the task would be
simpler if we could store energy easily. This is not easy on the scale that
would be required -- this is fortunate because, if it were easy, it would be
dangerous. The problem is the need to control the extraction of the energy
from such a storage, efficiently and safely. In the event of an accident any
energy store is liable to discharge, releasing large amounts of energy
unintentionally. The more easily and completely this energy can be released,
the better is the store but the more potent and devastating is any potential
accidental discharge. So energy storage appears as a safety hazard as well as
a desirable element of an energy utility. The danger of large amounts of
stored energy is exemplified by a hydroelectric dam, as discussed further in
34 Chapter 3: Rules, Evidence and Trust
Chapter 7. The important question is the quantity of stored energy that has to
be released safely in the event of an emergency. A coal, oil or gas fired power
station can be turned off quickly without releasing stored energy, provided
that the fuel supply itself does not start to burn [2]. Interestingly, fusion power
has remarkably low stored energy: when the reactor is turned off, energy
production ceases immediately, but that is not available yet. A nuclear fission
reactor is different – like a hydro-electric dam, it has a large stored energy
and some of this continues to leak out in the days and months following turn
off. This is the decay heat that has to be dispersed effectively somehow, and
the accident at Fukushima Daiichi demonstrated how difficult this can be.
Nuclear energy
For any source of energy there are two important measures, energy density
and intermittency. Energy density is the energy available per kg, and this is
discussed further in Chapter 7. Some energy sources have such low densities
that they cannot deliver the energy needed without an unreasonably large
mass of fuel, or moving air or water, etc. Use of an energy source is made
increasingly difficult if it is intermittent when the demand is continuous.
Then some full scale backup supply or energy storage becomes important.
Large scale sharing or averaging of many intermittent sources on a grid
seems an attractive alternative but its success depends critically on the
distance between sources and their pattern of intermittency. If the distance
over which the supply has to be shared becomes large, the capital cost or the
success of the sharing may fail. Thus wind, wave and solar power are only
available for a fraction of the time, or in particular places, sometimes where
fewer people live and work. Although coal, oil and gas discharge their waste
carbon dioxide straight into the atmosphere, they do have a high energy
density and are not intermittent unless political forces intervene – they can
provide energy at any place and time. Geothermal power, like hydro power
and tidal power, is effective where it is available, but that is the exception.
Thermonuclear power, that is fusion power on Earth, will be very important
when it becomes available, but a few decades of development for the
materials and reactor construction are needed first. A pre-prototype reactor,
ITER, is under construction in France and this will be followed by a full scale
prototype. However, for the more distant future it does offer the real prospect
of unlimited power using small quantities of ubiquitous fuel.
Nuclear fission has a high energy density – just how high may be illustrated
by comparing it with a state-of-the-art lithium battery – the grounding of the
Boeing Dreamliner in 2013was caused by difficulty with the energy retention
of these batteries. Fully charged they store 0.2 kWh of energy per kg. That
may be compared with the energy stored in 1 kg of thorium-232, that is 100
million times greater. Put more graphically, 100,000 tonnes of fully charged
Nuclear is for Life. A Cultural Revolution 35
lithium batteries (the mass of the largest super tanker) hold the same energy
as 1 kg of thorium-232. Even a nuclear physicist has to marvel at these
figures.
As for intermittency, energy from a nuclear fission reactor is as effective as a
fossil fuel plant. It can be available at all times and can be built anywhere,
even in an earthquake zone. It does not have to wait for the wind, a sunny day
or the tide to turn, and its environmental impact, underlying cost and accident
record are second to none. Although improvements, like the use of thorium as
a fuel, will become available within a few years, the equivalent uranium
version is not new technology. It is available now, and has been for half a
century.
Two soluble problems of power from nuclear fission
There are just two residual problems: firstly, a widespread public and
political phobia attaching to anything described as nuclear or related to
radiation; secondly, international regulatory authorities who, instead of
working to dispell this radiation phobia, act to enhance it – and have persisted
in doing so for 60 years. These problems could be easily overcome, if enough
people set their minds to it. However, on the back of these two concerns an
impression has been created that nuclear energy is inherently expensive and
that its waste is a problem – neither of which would be true in an informed
world.
A real understanding of nuclear technology and its effect on life is sparse
among scientists, and in the wider population it is lacking altogether. In the
following chapters we look at radiation and nuclear technology through the
eyes of different disciplines. Although the use of nuclear energy is often
described as complex or sophisticated, it is simple to grasp the basic facts
sufficiently to appreciate its safety. The phobia continues to fuel stories in the
press and popular literature and these have been self-sustaining.
There are new international moves [3] to question the policy of the various
international and national safety authorities who have failed to correct
dangerous misapprehensions about the safety of radiation. We need to
understand the diverse reasons for the reluctance of these authorities to
respond so far, but their steadfast adherence to the pseudo-science of LNT
cannot continue to withstand the evidence for long.
Widespread myths that should be contested
Though admitted by few, the mass of the human race seeks out irrationality.
As President Kennedy says in the quotation at the head of this chapter,
although an unreasoned opinion can be comfortably embraced without effort
or expense, confronting it takes time, study and even pain. Fortunately, there
36 Chapter 3: Rules, Evidence and Trust
are people who want to make a difference and leave their mark. It is salutary
to read of the experiences that Marie Curie went through to make sense of the
mass of tangled observations which led her to the understanding of the
atomic nucleus as it stands today. Her story gives an extraordinary example
of what can be achieved under adverse conditions [4, 5]. Unfortunately, many
in the affluent world effectively deny her painstaking work, preferring to
imagine nuclear energy and its radiation to be part of a malign and irrational
game of chance – until, that is, they are in the hands of clinicians using it to
cure them of cancer or otherwise extend their lives.
With more study, every member of the public could understand more and
forsake some of the answers that have been simply repeated and copied, over
and over without questioning for the past 70 years. Why? Because those
answers do not fit the medical and biological facts: the popular account of
nuclear radiation and its effect on life given in the media is mistaken and the
real effects are usually harmless and often beneficial, contrary to Hollywood
dramas and stories.
So should mankind take the hard decisions of real life, or choose exciting
make-believe stories that avoid having to study, just briefly, in the footsteps
of Marie Curie? The real problems that threaten the future of mankind in the
twenty-first century are not hidden. The need for food, water and a space to
live have not changed, but with rising expectations and expanding
populations, the requirement for education and real scientific understanding
have become paramount. The total misapprehension of nuclear technology at
all levels, even among many scientists, should be corrected because, when
understood even at a simple level, the ability to contribute solutions to
civilisation's larger problems can be appreciated.
What happened at Fukushima Daiichi in 2011
Japan's preparation for the earthquake
The Great East Japan Earthquake, also known as the 2011 Tohoku
Earthquake, occurred at 05.46 UTC on 11 March 2011. Its magnitude was 9.0
on the Richter Scale and it generated an exceptionally large tsunami that hit
the northeastern coast of Japan. Although this is thought to have been the
largest earthquake to hit Japan in a thousand years, the Japanese have studied
earthquakes extensively and their building codes dictate that buildings should
withstand significant disruptive forces. In October 2011 when I visited the
region some roads were still damaged by subsidence, but relatively few
buildings appeared affected. A school building that I visited in Fukushima
City had been damaged, but its replacement was already completed and ready
for use. The preparedness of the buildings was matched by the disciplined
Nuclear is for Life. A Cultural Revolution 37
and organised reaction of the people; they all knew that after such an
earthquake they should expect aftershocks and should prepare immediately
for a possible tsunami. Accordingly, as soon as the earthquake was detected,
the population took to higher ground and other places of safety from the
tsunami. Schools followed practised routines and moved quickly. Inevitably,
hospitals and homes for the elderly were not able to react quite as fast.
Reactor shutdown and decay heat
Across Japan the earthquake itself triggered an immediate shut down of all
nuclear power reactors that were working at the time. A shut down in the case
of a nuclear fission reactor means that all neutrons are absorbed by the
control rods, released to drop into the reactor. Consequently as soon as the
reactors were shut down in Japan all energy production by nuclear fission
ceased immediately, long before the tsunami arrived.
Neutrons are the go-between that enable the fission of one nucleus to cause
the fission of more. If a fissile nucleus absorbs a neutron, it is likely itself to
undergo fission almost immediately, thereby releasing further free neutrons.
This nuclear chain reaction can only be mediated by neutrons; it can be
stopped by the control rods, made of non-fissile nuclei which absorb neutrons
particularly readily, but do not undergo fission, thereby breaking the chain.
However, although there is no more fission following reactor shut down,
there is still some declining residual nuclear activity because many of the
Illustration 12: A graph to show how the power of decay heat from
a fission reactor falls with time after it is shut down . Note that
both scales are logarithmic so that the low power after later times
is shown as well as the higher power at early times.
38 Chapter 3: Rules, Evidence and Trust
products of fission are still liable to decay. This releases energy known as
decay heat as they change into more stable atoms. It is important to
appreciate how quickly this decay heat declines initially. Immediately upon
shut down it is 7% of the thermal power of the reactor, falling quite quickly
to just over 1% after a day, as shown in Illustration 12 However, it falls more
slowly as time goes on – after a year it is still 0.08%. Every reactor behaves
similarly.
The reason for the shape of this curve of declining activity is that it is
composed of the independent decay of many different nuclear isotopes, each
with its own simple exponential decay and half-life. Initially the activity is
dominated by the effect of the species with the shorter lifetimes, while later
on, effectively, only the contributions from the longer-lived isotopes remain.
At Fukushima Daiichi the concern was the decay heat produced in the early
hours and days.
This energy has to be removed by the continued circulation of cooling water,
otherwise the whole reactor will heat up rather quickly. But if the reactor was
not shut down when the accident occurred, like the one at Chernobyl, the
thermal energy production rate would be 2,000 to 3,000 MW, the same as the
level of cooling needed in normal operation. In other words the shut down of
each reactor at Fukushima reduced the scale of the initial energy available to
a few percent of that at Chernobyl, and if that cooling had been maintained,
there would have been no accident at all.
Tsunami arrival
The movement of the sea bed caused by an earthquake pushes and pulls the
water like a hydraulic ram creating a wave on the surface of the ocean above.
This wave moves at a speed of several hundred kilometres per hour
depending on the depth of the ocean [6]. As it reaches shallower water this
tsunami wave moves more slowly but its height increases. Then, like any
wave reaching a normal holiday beach, it breaks – in fact, in a trough where
the water is shallower the wave moves more slowly, but on a crest where the
water is deeper the wave moves faster, until eventually the next crest catches
up with the previous trough, causing the wave to break. In the case of a
tsunami wave it can rise up and break in a particularly dramatic fashion.
So 50 minutes after the quake such a tsunami wave arrived at Fukushima
You can calculate roughly what power such a reactor would produce by
decay heat a day after shut-down. If before shut-down it was generating
1,000 MW of electric power with a thermal efficiency of 33%, the answer
is just over 1,000 × 1% / 33% = 30 MW.
A year later it would be down to 2.4 MW.
Nuclear is for Life. A Cultural Revolution 39
Daiichi. As the wave height increased it broke, carrying all before it as it
rushed inland, smashing boats, houses, cars, shops, factories, power lines,
roads and railways along the length of the coastline. Interestingly, the boats
that survived were the ones that left port quickly before the tsunami wave
arrived at the coast. Out at sea in deeper water the wave had not yet broken
and was much smaller.
Reactor damage by tsunami
Thanks to their robust design none of the nuclear reactors in Japan was
damaged by the earthquake although many were 40 years old. The
Fukushima Daiichi nuclear plant suffered slight peripheral damage from the
tsunami, because it had been constructed too low down and close to sea level.
Specifically, its ancillary back-up diesel generators were sited in buildings on
the seaward side, so that when the tsunami arrived, these were flooded and
the main power lines to the plant were also destroyed, thereby leaving the
plant without power, once the energy from the short-term battery back up was
exhausted. After that three of the six reactors had no means to disperse the
decay heat discussed above. In addition, there were water-filled tanks
containing spent fuel elements that also needed to be cooled, because they
too released decay heat, albeit very much more slowly being further down the
curve shown in Illustration 12.
The chemical story
What actually then happened to the reactors and fuel ponds at the Fukushima
Daiichi plant? The continuing output of heat from the reactors concerned
could not be cooled initially and so the temperature of each reactor core rose,
and continued to rise. Although nuclear activity itself is not affected by
temperature at all, that is not true of chemical reactions. Each reactor was full
of water, designed to moderate or slow down the energetic neutrons and carry
away the reactor energy to the generating turbines when the reactor was
working, and so also keep the reactor cool. With the reactor shut down, this
flow of water is still needed to carry away the decay heat. Within the reactor
core with its pressure vessel inside the containment vessel, the uranium fuel
is sealed in tubes of zirconium, a metal whose only role is to keep the fuel
and its fission products isolated from the water. When re-fuelling becomes
necessary these tubes can be withdrawn cleanly, taking all the radioactivity
with them, and be replaced or moved to a new position in the core. Zirconium
is chosen because it plays no part in the nuclear reactions and is also
chemically rather inert.
However, like most metals at sufficiently high temperatures zirconium reacts
with water. This chemical reaction produces zirconium oxide and hydrogen
gas. The metals sodium and potassium react in a similar way at room
40 Chapter 3: Rules, Evidence and Trust
temperature, as shown in every school chemistry laboratory. Aluminium and
iron effectively do the same when they corrode – so this stage of the story is
not nuclear at all, but simply chemical. In the case of zirconium in water this
reaction to form hydrogen begins if the temperature exceeds 1,200 C. So at
Fukushima Daiichi the temperature rose and the zirconium corroded in the
water, generating hydrogen gas. The story developed slightly differently in
the three reactors, but the effect was qualitatively similar [7]. The pressure
inside the containment vessel, already very high because of the temperature
and the superheated steam, rose even further with the added hydrogen
eventually reaching 8.5 atmospheres. The vessel was designed to withstand
5.3 atmospheres and so was in serious danger of rupture.
Radioactivity released into the air
So it became imperative to release the excess pressure – but something else
had happened. The unused fuel and the radioactive actinides and fission
products had spilled into the water from the damaged zirconium fuel
elements. By releasing the pressure intentionally, steam and hydrogen
escaped into the atmosphere but carried with them some volatile fission
waste products, in particular the isotopes iodine-131 and caesium-137 [8].
(This radioactivity was not released into the environment by any explosion.)
The total released activity of these isotopes was measured by several groups
and is reported to be about 15% of that released at Chernobyl [9 ,10].
What happened next was really less significant although it seemed dramatic.
As every science student knows, a mixture of hydrogen and oxygen can
explode making water vapour. It is not clear what triggered the explosion but
the hydrogen was very hot, so it would not take much. Anyway, the released
hydrogen became mixed with the air outside the reactor and the resulting
explosion was captured on video and transmitted round the world with the
graphic description explosion at crippled nuclear reactor. Although true, this
generated panic among those who did not understand that the explosion was
not itself nuclear, was wholly outside the reactor and did not result in the
release of any extra radioactivity at all – that had happened already when the
hydrogen and steam were released. However, the panic, alarm and implosion
of trust were real enough and were responsible for the dramatic setting of the
major health scare and economic consequences of the Fukushima Daiichi
accident.
Re-criticality suppressed
To stop the creation of further hydrogen and disintegration of the fuel rod
assemblies the temperature within the reactors had to be reduced. Initially
this was achieved by circulating seawater through the cores. At the same
time, extra boron was added to the water, in the form of boracic acid.
Nuclear is for Life. A Cultural Revolution 41
Naturally occurring boron contains 20% boron-10 which is an exceptionally
strong neutron absorber and so boracic acid acts like the control rods
suppressing any possible neutron flux [11]. It has been confirmed that as a
result there was no restart of nuclear fission, a process called re-criticality.
This was in spite of the damaged fuel rods that melted and fell to the bottom
of the 2.6 metre thick concrete containment vessel which they then eroded to
a depth of 0.65 metre in reactor 1. In reactors 2 and 3 the depth was 0.12 and
0.20 metres respectively. This meltdown, so graphically described in
Hollywood movies, was seized on by the media as a matter for horror, but it
was less significant than the actual releases of radioactivity into the air and
the cooling water. This meltdown should not be seen as a near-miss major
incident. Criticality is hard to achieve in a carefully designed nuclear weapon
with weapon-grade high purity fuel. There was no chance of an enhanced
neutron flux, let alone an explosion in this case. If the melted fuel or corum,
as it is called, had eaten its way through all layers of containment, the
residual mess would not have compared with Chernobyl where a large
fraction of the core contents was thrown into the upper atmosphere and the
local environment, with remarkably small loss of life.
Radioactivity released into the water
As cooling was re-established, water passed through the reactor with its
damaged fuel rods and came into direct contact with fission products,
including iodine-131 and caesium-137, which are normally fully contained
within the rods. These elements dissolve easily in water so that this became
radioactive. In the immediate aftermath of the accident this radioactive
cooling water was held in tanks awaiting proper filtration, but in the first few
weeks there was inadequate storage capacity. That is why some of the less
radioactive cooling water had to be released into the ocean to make room for
that which was more highly contaminated. This was fully and properly
announced, but the publicity went seriously awry, as discussed below. In
addition, there have been some unintentional leaks and contamination of
ground water; again, public perceptions have been misinformed. There were
no direct health consequences of this released radiation or radioactivity, itself,
for either the workers or the public. We come to the indirect social and
psychological consequences later.
Spent fuel ponds
In addition to the cooling water for the reactors themselves, there was the
water in the spent fuel ponds. This is intended to act as a radiation shield as
well as a coolant; the ponds contained fuel that had been recently unloaded
from a reactor undergoing maintenance, as well as long-term used fuel,
destined for eventual reprocessing and storage. The fuel in the ponds
contained no iodine-131 because nuclear fission had ceased much earlier –
42 Chapter 3: Rules, Evidence and Trust
that is many times its 8-day half life. Further, because it had not suffered the
extreme heat of the recently shut-off cores, the spent fuel rods did not
contaminate the water to the same extent. As it turned out, there was damage
to the stored spent fuel rods in the ponds but the integrity of the ponds
themselves was maintained and the water did not boil away, as some
observers had speculated. Nevertheless, early in the accident concern for the
spent fuel contributed to the political decision to attach severity 7 on the
International Nuclear Event Scale (INES), the same as Chernobyl. This scale
is discussed again in Chapter 6: it is not science-based and does not actually
measure anything. It seems to be used by the authorities concerned to
emphasise to the public the difficulties that they face. Unfortunately, the
number looks like quantified science, but, by giving Fukushima parity with
Chernobyl, the authorities succeeded in amplifying the problem of public
concern, while improving neither trust nor understanding.
Public trust in radiation
Ignorance and lack of plan
Without power for lighting and adequate basic instrumentation, the operating
crew at Fukushima Daiichi were in a technically difficult position, but they
were also under great personal stress, as was Japanese society as a whole.
This was because the planning, education and personal instruction that had
proved so effective in reacting to the earthquake and tsunami had never been
extended to the possibility of a nuclear accident. When it came to radiation
and the release of radioactivity, there was complete ignorance, not only
among the general population but at the highest levels of authority too. There
was a general understanding that accidents were not possible because of the
design and the regulations applied [12]. Disengagement from any personal
responsibility or understanding of nuclear risks was not just national but
international too. The buck was always to be passed upward with no really
knowledgeable responsibility being taken at any level. Any aspect of life, not
just a nuclear event, that encounters this level of ignorance and centralised
reaction is a source for instability, especially when rapidly reported and
amplified by modern 24-hour media. Inherent in this reaction was the
perception that any understanding of nuclear safety requires a higher level of
expertise.
The fallacy of absolute safety and the loss of trust
Among those on the ground in the Fukushima Prefecture, there seems to have
been no one with any knowledge of the effect on public health of a nuclear
accident and no one who had read the recent UN/WHO reports on Chernobyl
and who had the necessary authority and confidence on which to base
Nuclear is for Life. A Cultural Revolution 43
decisions. There were engineers who could speak of the reactors, but no one
in authority to explain the medical implications for real people beyond the
words of regulation. When the radioactivity was released, the public had no
background knowledge on which to react to the news of the accident. In
particular the scale of the danger was hidden from them, and so, for them, the
natural reaction was to assume the worst.
The language of extremes carries no guidance or reassurance. In planning for
the future, the possibility of a nuclear accident had been dismissed on the
basis of assurances that it should not happen and that serious accidents can be
prevented with sufficient safety measures. This is a mistake in principle
because absolute safety is not possible. Every threshold can be exceeded,
every protection overwhelmed, and nature is always capable of
overwhelming man's best efforts – it can stage an accident by force majeure.
Today, whenever this happens, the media adopt the story and quickly present
themselves as being on the side of a mis-informed public, while repeating
and amplifying their fears. In this respect the accident at Fukushima was
worse than that at Chernobyl, where there was no free local press at the time
of the accident. Following straight after the spectacular video of the tsunami,
the news from Fukushima Daiichi with its video of the chemical explosions
spread around the world, exciting the modern appetite for a sequel.
Obviously the tsunami was natural and could not be blamed on anyone, but
the released radiation was man-made and therefore open to speculative
political story-making. The media and their customers preferred accounts of
reactors spewing radioactive material, generating for the audience horrific
visions of dragon-like happenings, seemingly beyond the control of those in
charge and the public imagination. By their repeated use in the daily press,
the very meaning of the words spewing and crippled were changed in the
language, as reporters exhausted their supply of other words to use.
These reports referred to levels of radiation as high without any attempt to
explain what made a level high or otherwise. The consequence was a
widespread haemorrhage of popular confidence in social and political
structures in Japan and in science worldwide, with very few authorities
prepared to staunch the flow in the early days when it mattered most [SR8].
Such a loss of trust is dangerous, as it threatens the cohesion of society itself,
especially when it is based on a completely false assessment of the situation
ramped up by 24-hour reporting.
44 Chapter 3: Rules, Evidence and Trust
Impact on public health
Most of the radioactivity was carried by the wind out to sea or inland to the
north-west, in the general direction of the village of Iitate. The dashed circles
shown on the maps, Illustration 13, at 20 and 30 km from the Fukushima
Daiichi power plant itself, were used to define the evacuation zone. Later this
was extended in the northwest sector because of the effect of the wind on the
Illustration 13: Maps of the region around Fukushima Daiichi
showing colour-coded radiation dose rate in the air 1 m. above
ground in micro-Gy per hour. The red region is above 19 micro-Gy
per hour or 21 mGy per month. The four maps are for different dates
after the accident. The dashed circles are shown at 20km and 30km
from the plant. [Reproduced by kind permission of WNA.]
Nuclear is for Life. A Cultural Revolution 45
pattern of deposited radioactivity. To put the meaning of the coloured areas
into simple perspective, anyone living permanently in the green zone would
get an extra radiation dose rate equal to twice the natural rate in Colorado (6
mGy per year) where the cancer rate is less than the US average. The dose
rate in the dark red regions (250 mGy per year) is a third of the safety
threshold set by ICRP in 1934 (730 mGy per year) and, even by today's
standards, carries no known risk of cancer. We look at this again in Chapter 9.
The area devastated by the tsunami was along the coastal strip and those
areas where radioactivity was higher were mostly inland in the mountainous
area beyond the reach of the tsunami. It has therefore been possible to
separate the effects of the two accidents, although the situation became
slightly more confused when some of those made homeless by the tsunami
were accommodated in temporary accommodation in schools and halls
inland, some in regions affected by higher radioactive contamination (see
also evacuee account in Chapter 12).
The maps show where the radioactivity was carried by the wind, but the
related fear spread around the world on the media. In addition to the official
evacuation of Iitate and the 20 km zone, there was a larger and more
significant voluntary exodus. School attendance by children from better-off
families fell as a result. Unofficial news of voluntary evacuation encouraged
people not to be left behind and at risk, as they saw it, and those who could
flee most easily did so, even from Tokyo, some 150 km away. Many
foreigners acted impulsively and caught a plane in search of absolute safety,
receiving more radiation on the plane than if they had stayed put. Many
foreign embassies set a poor example and encouraged evacuation – some
moved their whole staff to cities elsewhere in Japan. Some officials, quite
ignorant of what they were running away from, spoke darkly of a possible
need to evacuate Tokyo. Most Japanese remained, bolstered by their
proverbial stoicism, and the workers at the plant, treated by the world press
as condemned men and women, stayed at their posts. History should find
some way to record its thanks to them and their families for their bravery.
Protective suits that frighten or impress
Meanwhile, anxious to impress, officials, visiting dignitaries and press
reporters eagerly donned impressive white protective suits and masks,. Such
antics may make good television and improve the authoritative image of
those who need to be seen doing something about the accident. But they do
nothing for a Japanese child and her mother who see the school playground
being dug up by workers dressed up in the name of an unseen and
unexplained evil called radioactivity or radiation. This is made only worse
when this supposed evil actually causes no harm whatever at the doses
concerned. The harm comes from the fear that the image of dressed-up
46 Chapter 3: Rules, Evidence and Trust
workers engenders, and from keeping children indoors rather than letting
them out to play naturally. Unfortunately the majority of the population see
their fear confirmed as established fact when workers and officials are
dressed up in this way. An open-necked shirt with rolled-up sleeves, a firm
hand shake and a cup of tea would be a better way to reassure.
Loss of life
There were two deaths at the nuclear plant in the first hours, but these were
drownings caused by the tsunami itself. Some workers who got their feet wet
in the basement flooded by radioactive water suffered beta burns to the skin
on their legs, but this soon cleared up. Within a couple of weeks of the
accident there were enough preliminary measurements to show that the
released radioactivity was substantially less than at Chernobyl and it was
clear that there were unlikely to be any casualties at all, even in the longer
term [SR8]. Regrettably this was only acknowledged by the international
authorities after a two-year delay during which considerable social and
psychological damage continued. The Press Release by UNSCEAR (United
Nations Scientific Committee on the Effects of Atomic Radiation) reads:
31 May 2013 – Radiation leaked after Japan's Fukushima nuclear
disaster in 2011 is unlikely to make the general public and the
majority of workers sick, a United Nations scientific committee today
said previewing a new report..... The committee added that no
radiation-related deaths or acute effects have been observed among
the nearly 25,000 workers at the accident site, nor it is likely that
excess cases of thyroid cancer due to radiation exposure would be
detectable.[13]
Recent reports on the Chernobyl accident [14] confirm that there was no
evidence for any other cancer types, even there. Given that the release of
radioactivity at Fukushima is known to be substantially smaller than at
Chernobyl, no cancers of any kind are likely at Fukushima. The same
conclusion may be reached by comparing doses to Fukushima workers to
survivors of Hiroshima and Nagasaki, and of the Goiania accident described
in Chapter 6.
Caution that harms people but protects authority
Psychological disaster at Fukushima
Geraldine Thomas, Professor of Molecular Pathology at Imperial College
London and Director of Chernobyl Tissue Bank, [15] has described the real
damage:
All the scientific evidence suggests that no one is likely to suffer
Nuclear is for Life. A Cultural Revolution 47
damage from the radiation from Fukushima itself, but concern over
what it might do could cause significant psychological problems. It is
therefore important to understand that the risk to health from
radiation from Fukushima is negligible, and that undue concern over
any possible effects could be much worse than the radiation itself.
This fear has been caused in large measure by the inept international advice
available via the various arms of the United Nations, specifically UNSCEAR
and ICRP (International Commission for Radiological Protection). The
advice to national governments is intended to manage popular fears by
appeasement with an over-cautious safety policy. This is not based on the
science of any actual risk, and it fails completely at a psychological and
social level in the case of high profile accidents. It should be considered
inhumane. The accident at Fukushima was not a radiation disaster, but many
died as a result of it, not from radiation but from social stress. Nobody in
Japan, or in the international community advising them, seems to have read
and understood that the same mistake was made at Chernobyl, as most
recently reviewed in a report by UNSCEAR on 28 February 2011, just 11
days before the Fukushima accident [16]. That report repeated that the severe
disruption caused by the Chernobyl accident resulted in
major social and economic impact and great distress for the affected
populations.
As an article in Nature about the May 2013 report on Fukushima said [17]
A far greater health risk may come from the psychological stress
created by the earthquake, tsunami and nuclear disaster. After
Chernobyl, evacuees were more likely to experience post-traumatic
stress disorder (PTSD) than the population as a whole, according to
Evelyn Bromet, a psychiatric epidemiologist at the State University
of New York, Stony Brook. The risk may be even greater at
Fukushima. “I’ve never seen PTSD questionnaires like this,” she
says of a survey being conducted by Fukushima Medical University.
People are “utterly fearful and deeply angry. There’s nobody that
they trust any more for information.”
Overall, the reports do lend credibility to the Japanese government’s
actions immediately after the accident. Shunichi Yamashita, a
researcher at Fukushima Medical University who is heading one
local health survey, hopes that the findings will help to reduce stress
among victims of the accident. But they may not be enough to rebuild
trust between the government and local residents.
The conclusion that the reports lend credibility and offer hope are hardly
appropriate, given that the danger and the required action was clear within a
48 Chapter 3: Rules, Evidence and Trust
few days, as posted two years earlier [SR8].
Symbols of hazard
Authorities worldwide have used a symbol to encourage exceptional respect
for radiation hazards. When it was first introduced, the tre-foil of radiation,
Illustration 8a on page 9, may have been informative, but quickly it became a
symbol that frightened people – like a swastika or a skull-and-crossed-bones.
Its use as a practical danger signal became misused for purposes of
intimidation and politics. It lost any educational benefit long ago and its use
should be discontinued. To many people it is seen as some kind of symbolic
curse – and a curse is not a reasonable instrument of safety. For instance,
when used as a symbol attached to radioactive waste, it conveys, not
information, but a message of great danger, usually where none exists.
A far greater hazard responsible for millions of deaths annually through
dysentery and other water-borne diseases has no such symbol, probably
because it is a Third World, more than a First World, problem. Illustration 8b
on page 9 shows a candidate symbol drawn from the First World experience.
Evacuation, clean up and compensation
At Fukushima the lack of trust, so evident on my first visit in October 2011,
appeared to be equally strong in December 2013. I was introduced by an
evacuee to his empty farmhouse and overgrown fields in the evacuated zone.
I visited his cramped temporary accommodation where three generations
were still living and enjoyed a meal at the café on the site. I learnt of his
earlier alcohol problem and how by then he had a part time job as warden
Illustration 14: An entry gate to the evacuation zone, photographed in
December 2013.
Nuclear is for Life. A Cultural Revolution 49
checking the empty houses and farms in the evacuated zone – which is how
he was able to take me in through the locked barrier at the zone boundary
(Illustration 14). I saw decontamination work in progress in the fields
(Illustration 15) and monitoring stations with piles of sheeted contaminated
top soil awaiting removal (Illustration 11 on page 12).
Later I heard that the evacuee who showed me around had been able to buy
himself a sizeable two-storey house outside the zone with the compensation
money he had received. Compensation, and those who get it and those who
do not, has upset the local housing market and is a source of grievance that
has compounded distrust of the authorities for their handling of the
evacuation and clean-up.
Fear of artificial radiation
In their attempt to find safety, people seek what they see as familiar and
natural, perhaps because it is less likely to have been tampered with for some
unknown purpose. But for community decisions, like sources of energy that
affect everyone, such preferences should be justified by evidence. In
connection with nuclear energy we should ask whether natural radioactivity
in the environment is more benign than any possible artificial radioactivity
released from a nuclear power plant.
Radioactivity is present everywhere in the natural world. Modern cosmology
teaches that after the Big Bang, 13.8 billion years ago, the universe was
dominated by radiation and the only elements present were hydrogen and a
small amount of helium. All the other material that we see around us now,
and from which we ourselves are made, is the nuclear waste from stellar
explosions that happened later. Although nuclear activity has been notably
quiet recently, at least in this part of our galaxy, that is certainly not true
elsewhere in the universe, where nuclear action is widespread. We can see
Illustration 15: Stripping fields of contaminated topsoil, photographed
in December 2013.
50 Chapter 3: Rules, Evidence and Trust
this in the amazing pictures of prodigious explosions and violent collisions
that come from the Hubble and other powerful telescopes.
If that makes us think we have been lucky, we should not forget the
radioactive decay heat that followed the formation of all our chemical
elements as nuclear waste more than six billion years ago. Today the longest
lasting but naturally unstable radioactive elements are still here – uranium,
thorium and potassium-40 – decaying with their half-lives measured in
billions of years. Natural and harmless, you might think, after such a long
time. But the energy that they release is the source of the heat inside the Earth
– it is decay heat, like the heat that caused the trouble at Fukushima. It is
responsible for all geothermal heat sources in Iceland, Yellowstone National
Park and elsewhere. It provides the heat and radioactivity for the onsen, the
hot springs so important in Japanese culture, as well as the spas in Britain and
the Baden in Germany that have been so popular since the time of the
Romans. Today it is said that 75,000 patients worldwide seek radon therapy
at these facilities [18]. More generally the radioactivity provides the energy
that drives the movement of the Earth's tectonic plates – and so the
volcanoes, earthquakes and tsunamis. In fact, this nuclear decay heat of the
Earth, which is natural, killed 18,800 people in Japan in March 2011, while
radiation emanating from the man-made reactors at Fukushima Daiichi killed
not a single person. This shows how that which is man-made or artificial may
be safer than what is found in nature, benefiting as it does from being
designed and matched to the scale of human need. However, the distinction is
only one of scale, since there is no real intrinsic difference between natural
and artificial sources of radiation.
Questions about the danger of internal radioactivity
Domestically, the Japanese people are particularly concerned about
cleanliness, so the possibility of radioactive contamination around the home
causes much worry. But the thought of indelible contamination within your
own body, beyond the reach of normal washing, is even more disturbing. So
internal radioactivity and the cancer that such radiation might cause in years
to come makes for deep concern. How can the Japanese people be sure that
the internal radiation from the doses experienced at Fukushima is safe? Why
is it unexpectedly harmless? Why have the Japanese people not been told
anything about this? These questions are answered fully in Chapters 5 and 6,
where we discuss how cancer therapy works and what happened in the town
of Goiania in Brazil in 1987, when a redundant radiotherapy source was
taken from a medical clinic.
Nuclear is for Life. A Cultural Revolution 51
Comparison of the accidents at Goiania and Fukushima Daiichi tells us what
we need to know about the chances of cancer caused by the radioactivity
released in the power station accident. This comparison uses measurements
taken in a very large survey of public internal contamination at Fukushima,
discussed in Chapter 6. Many of those measurements were taken by the
mobile whole-body radioactivity measurement unit. This is shown in
Illustration 16 outside the General Hospital at Minamisoma, photographed
when I visited there in October 2011.
Radiation safety is inter-disciplinary
The social and economic consequences of the Fukushima accident have been
severe but avoidable, for the world, as for Japan. So why have both the
Japanese and the international authorities been spooked by this accident, if
the radiation has no serious medical effect on life? Firstly there is need to
confirm that this really is generally true, and not some special case. Given the
extreme energy of individual nuclear processes, how can it be that the effect
of nuclear radiation on human health is modest – or even beneficial at low
rates? This is a source of genuine surprise, even disbelief, to many physicists
and engineers, who are familiar with these energies and the principles of their
physical effect – though few are versed in the medicine and biology involved.
This cross-disciplinary fault line is a part of the problem. It is one reason for
the extreme caution applied to standards of radiation protection for the past
60 years. Marie Curie died in 1934 and the safety standards used then have
been superseded by others, a thousand times more cautious in response to
pressures from the public with the acquiescence of physical scientists. The
wide divergence of these perspectives needs to be resolved with data and
simple scientific understanding, as set out in later chapters.
Illustration 16: A new whole-body measuring unit photographed at the
Minamisoma General Hospital, October 2011.
52 Chapter 3: Rules, Evidence and Trust
Fear of the radiation from a CT scan
Ever since its discovery the penetrating powers of ionising radiation have
been used to picture the inside of patients' bodies, initially as simple X-ray
examinations and more recently as CT scans. These are now complementary
to MRI (Magnetic Resonance Imaging) and ultrasound scans, neither of
which uses ionising radiation at all. Together these methods have contributed
to the early diagnosis of many conditions, including cancers, as part of the
modern medical care that has increased life expectancy for so many.
Fractured bones, dental cavities and foreign bodies can often be seen with
quite small doses of ionising radiation, safely and effectively at modest
expense. If the clinician requires better resolution or discrimination in the
image, the radiation dose is increased. Over the years the method has been
extended to make 3D anatomical pictures with a resolution of a fraction of a
millimetre. Functional images, also in 3D, are given by PET (Positron
Emission Tomography) and SPECT (Single Photon Emission Computed
Tomography) scans in which a short-lived radioisotope is injected into the
patient – these are both described as nuclear medicine and deliver a radiation
dose similar to a CT scan.
Today many cancers are cured without the trauma of surgery, and the usual
treatment combines chemotherapy with high-dose radiotherapy (HDRT),
often simply called radiotherapy (RT). In many cases this has a good
prognosis, although the radiation doses used are hundreds of times higher
than used during a CT scan and may be given every day for a month or more.
The scares that appear in the popular press about the dangers of the low doses
used in diagnostic CT scans, as opposed to therapy treatment, are without
foundation, typically they are based on analyses of data that have been
discredited in the medical literature [19]. In later chapters we look at the LNT
hypothesis used in attempts to substantiate these scare-stories, why it is
discredited, and the history that explains why it was ever taken seriously by
scientists who had other motives (see Chapter 10). Here we note that patients
receiving the much higher doses in a radiotherapy course, usually thank the
clinical staff on completion of their treatment, and go home with a good
chance of enjoying further years of life. Such are the benefits of modern
medicine, and to refuse the much lower doses of a CT scan out of fear, makes
little sense. The risk from an undiagnosed tumour, missed by not accepting a
scan when symptoms suggested one, far outweighs the tiny risk from the scan
itself. Of course the expense of a scan should not be accepted without reason,
just as saying that a pedestrian crossing is safe to use should not be seen as an
invitation to stop and sit down half way across the highway. Common sense
should always be applied, but we all know that, and it applies to the safety of
radiation.
Nuclear is for Life. A Cultural Revolution 53
Wastes, costs and conflicting interests
Comparison of waste products
For many people, concern about high-level nuclear waste tops their list of
worries about nuclear energy, although with a little examination this can be
seen as unreasonable. Like other technologies, nuclear power produces waste,
and so strategies are needed to prevent safety being compromised or the
environment being spoiled. Technologies and their wastes may be compared:
whether the waste is toxic or contagious; whether the quantity is large;
whether it can be reprocessed; whether the toxicity decays away in time;
whether it is a gas or liquid that has been traditionally discharged into the
environment; whether it is soluble and easily dispersed; whether it is solid
and easily stored; whether it has other valuable uses.
For simplicity, let's compare three types of waste produced by human
activity: combustion waste, personal biological waste and high-level nuclear
waste [SR1].
Combustion waste consists of ash and carbon dioxide. In Illustration 9 on
page 10 the canister on the left shows the mass released into the atmosphere
every day for each person – the product of burning gas, oil and coal,
including their contribution to transport, heating and electricity generation.
The steady build-up of this carbon dioxide in the atmosphere is well
established, even if the precise time scale of the consequences is less certain
[SR3]. Anyway, the release of such pollutants from fossil fuel combustion is
out of control and threatens life on Earth.
Biological waste is closer to home and its management is an individual and
personal responsibility taught to children at an early age. Public discussion is
unwelcome, but nature encourages everybody (and animals likewise) to
control the release of waste into the environment by making it foul smelling –
presumably as selected by evolution. Where the resources are available, the
waste is washed away with water. However, where this fails and the waste
reaches drinking water or the food chain, a closed biological loop results
which, once infected, can lead to a biological chain reaction incubating
disease. A recent well-publicised example was the cholera epidemic in Haiti,
although in truth nearly a million children die every year from diarrhoeal
disease spread by polluted water. Where the necessary investment is made,
this waste problem is contained by recycling and engaging the process of
natural decay. The effluent is passed through filter beds and the solids aerated
to rot or decay naturally before being spread on arable or pasture land as a
valuable natural fertiliser. In this way simple treatment of a dangerous waste
product on a huge scale gives a valuable but safe product. This is accepted
without comment in the press.
54 Chapter 3: Rules, Evidence and Trust
Nuclear waste
Nuclear waste is another waste like biological and combustion waste.
However, unlike the latter two types, it has not caused any fatal accident.
Specifically, there has been no radiation fatality from waste at any nuclear
power plant. The quantity of waste is tiny by comparison, as illustrated by the
canister on the right in Illustration 9 on page 10. This is directly related to the
energy density of nuclear compared to carbon fuels – undiluted, a millionth
of the fuel is needed to generate one kilowatt-hour of electrical energy, but
that also leaves a millionth of the waste – the precise ratio depends on the
choice of fossil fuel and whether the nuclear fuel is fully burnt (the size of the
canister in Illustration 9 assumes that about 1% is burnt which is true in most
current reactors). The waste is mainly solid and can be compactly stored; it is
not discharged into the environment by default like carbon dioxide and
biological waste. Like biological waste, it can be reprocessed, the valuable
unused fuel recovered and reused, and other by-products used in the
manufacture of all kinds of useful devices from smoke alarms to sources for
sterilisation and vital medical scans.
The reusable fuel, uranium and transuranics including plutonium, have long
life times, but the residual fission products decay naturally with half lives of
30 years or less. So these can be chemically separated and embedded in glass
or concrete, and then buried. Within 300 years the activity falls by a factor of
a thousand, and within 600 years by a million, becoming no more active than
natural ores. The technology to vitrify the waste in this way is not new and
has been employed for several decades. (If, instead, the unused fuel is not
recovered or reused, the residual radioactivity lasts much longer – but that is
a waste of valuable unused fuel.) Buried in a mine, waste can stay put
securely for very much longer than 600 years, as demonstrated by the story of
the waste left by the 2,000-million-year-old natural Oklo Reactor. However,
we postpone a description of that story until Chapter 7. We also delay
drawing conclusions about proliferation and plutonium until Chapter 12.
Terrorists and rogue states are dangerous whatever means they use, but how
hazardous is plutonium?
Nuclear waste has had a bad press, but that is nothing to do with safety.
Compared to other wastes, it rates very well. What is the worst that can be
said of high-level nuclear waste? That it does not smell? Actually that is not
such a stupid question. The ability of life to detect radiation is important, and
we study that in Chapter 5.
The cost of nuclear energy
What about the cost? the media exclaim, and people nod their heads in
agreement. But think about it: where does the money go? It goes on safety,
insurance, public enquiries, working practices that ensure safety – on a grand
Nuclear is for Life. A Cultural Revolution 55
scale without equal! Well, if half the work force in the nuclear industry is
engaged working on safety, waste and decommissioning, and, if those
requirements were to be drastically scaled back without risk of any kind, the
cost of nuclear energy should fall substantially. By 30%, at least. But there is
no escaping the fact that the public clamour for even greater safety after
Fukushima has increased costs yet further, even though the fears are
groundless and the increased costs are not in the public interest. The ultimate
problem is a regulatory regime that demands that nuclear plant designs are
over-engineered in the name of safety. Behind that there is always a thirst for
employment, a readiness by business to secure a contract to do a job, and a
campaign by the press for increased safety.
In the Fukushima accident there was no loss of life at all due to radiation and,
apart from the need to ensure that emergency generators are better sited, no
major changes should have been required. Actually, the only substantial task
should be one of education – the authorities should wake up to that, and the
public should appreciate it. Education would address the real problem, be
relatively cheap, and the cost of electricity should fall dramatically, not rise.
But the story has wider dimensions. Japan has no native supply of fossil fuel
and its need for energy contributed to the causes of war in the twentieth
century. This problem had appeared solved with its introduction of nuclear
energy in the 1960s. However, currently (August 2015) all but one of its 50
nuclear power plants still remain shut down in response to public protest
following the breakdown in public trust after the Fukushima accident. The
impact on both the country's trade deficit and greenhouse gas emissions is
severe. Japan imported fossil fuels for 88% of its electricity in 2013,
compared with 62% in 2010. The additional fuel cost was ¥3.6 trillion ($35.2
billion). Japan reported a trade deficit of ¥11.5 trillion ($112 billion) for
2013, largely due, directly and indirectly, to additional fuel costs. This is
much more than the 2012 trade deficit, and follows a ¥6.6 trillion ($65
billion) surplus in 2010. Electricity consumption has decreased since 2010
and tariffs for industrial users have increased by 28%. Emissions from
electricity generation accounted for 486 million tonnes CO2, 36.2% of the
country's total in fiscal 2012, compared with 377 million tonnes, 30% of total
in 2010 [20]. Although on 11 August 2015 the first Japanese reactor was
restarted and others will follow, many have been permanently shut down
because of the costs of compliance with unreasonable regulations. The
situation is both needless and dire, but that is reflected to a considerable
extent around the world where other nuclear programmes have been shut
down, reduced or not started. This is less evident in countries where the
authorities are not at the mercy of short term popular opinion. In a democracy
having to conform to popular nuclear restrictions can reduce economic
competitiveness. Authoritarian regimes need not be so encumbered, and this
56 Chapter 3: Rules, Evidence and Trust
will give them a major competitive edge in future, both for electrical energy
itself and for the ability to deliver new plants. Over the next century this will
give them an economic advantage that many in the free world have denied
themselves.
The scale of a nuclear reactor
As a rule, when costs increase unreasonably, something is wrong, either with
the objective or the way that it has been set. Evidently the general
apprehension about nuclear technology has driven absurd increases in costs.
There are ways to reduce costs beyond simply addressing this apprehension.
Current nuclear reactor designs are very large for two reasons, one social and
one technical, but there are separate reasons why costs might be substantially
reduced if they were smaller.
The scale of a nuclear plant is set in part by the level in society prepared to
take responsibility for it. We may imagine a tiny plant supplying a village, a
small plant for a town, and a large plant for a region. But if responsibility is
not accepted locally it is referred upwards to a higher authority, although the
idea that authority improves with such centralisation is questionable.
Responsibility for the supply of electricity from nuclear energy has been
passed up the line, all the way to the top with the involvement of
international authorities. With some measure of dispersed responsibility,
nuclear plants might be smaller, less expensive and have faster time scales for
decision making and construction. Clearly, then, to reduce costs, much
devolved responsibility should be considered. Nuclear energy is not a special
case or category on its own. On what grounds would it be? That is precisely
the kind of pleading that should be avoided.
A second reason for nuclear plants being large concerns how they work.
Nuclear submarines are propelled by smaller nuclear reactors [21], but these
use more highly enriched uranium than civilian electric utilities. The
technical details concern the neutrons in the reactor; if the fissile uranium
density is not high enough, too many neutrons may escape from the reactor
core or get absorbed by fission products called poisons. By making the core
larger the number escaping is reduced and the efficiency is increased, and
that is what is done in a large traditional civil reactor. However, it is not clear
that this is essential and new designs for small modular reactors (SMR) may
be viable and cheaper. This is a matter of ongoing engineering debate.
SMRs would avoid the large in situ construction methods that have caused
difficulties for new plants. An important scale is the experience of the
builders. If nobody on site has ever built such a plant before, there will be
setbacks, overruns and delays. If on the other hand there is personal
experience from previous projects, and, in addition, much of the construction
involves modules assembled off-site, the economies of repeated production
Nuclear is for Life. A Cultural Revolution 57
will pay dividends in cost, reliability and safety. That is just economics,
Henry Ford style. Production line methods for managing nuclear waste can
reduce costs too. When competition and market forces, unfettered by heavy-
handed regulations, can get to work, new designs will prove themselves and
costs will fall. Proper safety regulation is essential as in other industries, but
there is no reason to treat nuclear risks as special or different, provided the
workforce is properly informed.
Notes on Chapter 3
1) Report of IPCC (2014) https://www.ipcc.ch/report/ar5/wg3/
2) The stories of Centralia, Pennsylvania, USA and Morwell, Victoria, Australia
show what can go wrong.
3) Scientists for Accurate Radiation Information (SARI) (2015)
http://www.radiationeffects.org
4) Radiation and Modern Life A book about Marie Curie by AE Waltar, Prometheus
Books (2004)
5) D Ham Marie Skodowska Curie (2003)
http://www.21stcenturysciencetech.com/articles/wint02-03/Marie_Curie.pdf
6) Fundamental Physics for Probing and Imaging An academic book by Wade
Allison, OUP (2006)
7) Facts and Lessons of the Fukushima Nuclear Accident, A Kawano (TEPCO)
American Nuclear Society, San Diego meeting, 12 Nov 2012
8) In addition there is caesium-134 and other radioactive isotopes of iodine. But
these make no qualitative difference and we ignore them in this simplified
account.
9) WNA on Chernobyl (2015) www.world-nuclear.org/info/Safety-and-
Security/Safety-of-Plants/Chernobyl-Accident/
10) WNA on Fukushima (2015) www.world-nuclear.org/info/Safety-and-
Security/Safety-of-Plants/Fukushima-Accident/
11) Boron used in the nuclear industry is enriched in boron-10. Since its atomic mass
is 10% different to the majority boron-11, this is quite easily achieved by
distillation, unlike for the isotopes of uranium that differ in mass by only 1%.
12) Unfortunately in 2015 the reassurance that nuclear accidents should be made so
unlikely as to be impossible still seems to be a political requirement. Seeking this
unrealistic goal is absurdly expensive.
13) UN news report on Fukushima (2013) http://www.un.org/apps/news/story.asp?
NewsID=45058
14) Health Effects of the Chernobyl Accident, WHO (2006)
http://whqlibdoc.who.int/publications/2006/9241594179_eng.pdf
15) Health effects - facts not fiction, Thomas GA (2013)
http://www.jaif.or.jp/ja/annual/46th/46-s3_gerry-thomas_e.pdf
16) New Report .... on Chernobyl, UNSCEAR (28 Feb 2011)
http://www.unis.unvienna.org/unis/en/pressrels/2011/unisinf398.html
58 Chapter 3: Rules, Evidence and Trust
17) Nature report on Fukushima (2012) http://www.nature.com/news/fukushima-s-
doses-tallied-1.10686
18) Radon mine (2015) http://www.radonmine.com/why.php
19) Regarding the Credibility of data ....., Socol and Welch (2015)
dx.DOI.org/10.1177/1533034614566923
20) WNA information on Japan (2015) http://www.world-nuclear.org/info/Country-
Profiles/Countries-G-N/Japan/
21) See United States naval reactors on Wikipedia.
Nuclear is for Life. A Cultural Revolution 59
Chapter 4: Energy to Support Life
Nuclear energy is incomparably greater than the molecular energy
which we use to-day. The coal a man can get in a day can easily do
500 times as much work as the man himself. Nuclear energy is at
least one million times more powerful still. If the hydrogen atoms in a
pound of water could be prevailed upon to combine together and
form helium, they would suffice to drive a 1,000 horse-power engine
for a whole year.
Winston S Churchill, in the Strand Magazine (1931)
Escalating stages in the liberation of life
Energy for plants 60
Energy for animals 60
External energy for humans 61
Energy production that damages the environment 63
Energy without harm to the environment 65
Externalising the power to think 67
Energy for excitement and risk
Need for fun and stimulation 68
The effect of news 69
Separating high from low risks in life 71
Energy as frightening 72
Safety in a natural disaster 72
Personal and national engagement with safety 73
Education and democracy 74
A Babel of disciplines and conflicting interests
Education in different logical voices 75
Physical science and linearity 75
Biology, medicine and the logic of evolution 78
General public and common sense 80
Committees that ensure caution 81
Industry and its search for business 83
Historical view 84
Other fauna and flora 84
Notes on Chapter 4 85
60 Chapter 4: Energy to Support Life
Escalating stages in the liberation of life
Energy for plants
The surface of the Earth is warmed when the Sun shines on it, but as soon as
night comes, the flow is reversed and the Earth cools by radiating its heat into
space. The atmosphere blankets the surface, and the heat stored during the
day in the rock helps to maintain the surface temperature. Whenever
temperature falls, chemical changes slow or stop, including those that
constitute the mechanisms of any form of life. When the Sun shines and it is
warm, plant life can absorb energy by photosynthesis, so that it grows while
also converting carbon dioxide in the atmosphere into oxygen. This is
summed up in the following equation:
energy + carbon dioxide + water → carbon/hydrogen (vegetable) + oxygen.
But at night this energy supply is cut off. In the winter the effect is even more
pronounced and the plant may have to die back and wait for the warmth of
spring.
Energy for animals
However, that is only the beginning of the story of life, because evolutionary
biology has always striven to find new ways to compete more effectively. If it
could take on board the products of photosynthesis by plants, that is food,
and combine it with oxygen when required, it could effectively run
photosynthesis in reverse and recreate the energy. Such a versatile energy
store would act as a battery, storing the Sun's energy to maintain life during
the night and in the winter:
vegetable matter + oxygen → energy + carbon dioxide + water.
Within a few hundred million years and with plenty of room to experiment,
that is what Darwinian evolution learnt to do. Forms of life using energy
from food no longer needed to sit immobilised in the sun all day, but could
move around – migrate by land, sea or air in search of the best source of
vegetable food and the most pleasant climate. Life could now use its heat
source, its energy battery, to keep its temperature optimised, night and day,
throughout the year. This food-powered animal life acts as a biologically
stabilised combustion engine – a pretty smart job compared to the ill-
controlled combustion of vegetation that occasionally catches fire in the open
environment. This sketch of metabolic life has omitted fish, birds and the
many forms of parasitic life that hitch a lift at different levels. However, the
story of how the energy flows is not upset by these additions.
Like plant life, animal life needs energy for growth and biological
maintenance. By consuming food as fuel, animal life enjoys energy for
transport and other motor skills that are denied to plants. Energy is also
Nuclear is for Life. A Cultural Revolution 61
available for competition between packs of animals of the same or different
species. From sport and friendly competition to fighting and war, this is the
essence of classical Darwinian selection, but today it is understood that this
principle applies further in fact, in the competition between life forms at
every level. For instance between viruses and their hosts, each player evolves
to find defences against attack by its adversaries. Imagine such a war game in
which one adversary never changes strategy, but the other is alive to change
and so evolves new strategies of defence and attack. The living player will
always find a way to evade the attacks, however long that takes and however
powerful the adversary; and he will find a way to attack his more powerful
adversary successfully, too. Initially individuals may not win but in the end
the selection of a winning strategy is guaranteed. This is the story that is
explored in Chapter 8, with radiation cast as the powerful but changeless
adversary, and living tissue in the role of the weaker, but artful, defending
player that has learnt to survive.
External energy for humans
The advance that lifted mankind above the other animals was the Promethean
step discussed in Chapter 2. In this the energy stored in plant growth could be
harvested and used now, not just inside, but outside the body, still reversing
photosynthesis, but in the process of combustion, ie fire. However the safety
built into the oxidation of vegetation within the body is then no longer
available. Mankind had to use his brain and introduce safety rules for
himself.
This was a turning point and the beginning of safety through careful thought.
From then on, safety was seen to be a matter not only for nature but also for
conscious decision-making and discipline, handed down to later generations
as an important ingredient of education. Initially this took the form of oft
repeated cautionary tales told to children. In recent centuries these appeared
in books that wove entertainment with instruction that was then more easily
remembered.
Illustration 17 shows a page from an English translation of the well-known
nineteenth century German children's book Der Struwwelpeter. While her
mother is out of the house, the child, Harriet, disobeys her mother's
instructions and plays with the matches, accidentally setting her clothes on
fire. As the pictures relate, she is then burnt to death to the dismay of her pet
cats, who are left weeping while only her shoes remain. With these dramatic
details, children remember the dangers of fire and their parents' instructions.
62 Chapter 4: Energy to Support Life
Illustration 17: "Harriet and the Matches" from Der Struwwelpeter
Nuclear is for Life. A Cultural Revolution 63
A further change in mankind's engagement with energy came at the start of
the historical era when he discovered that a vast store of the product of many
millions of years of photosynthesis lay fossilised in the Earth, both in the
form of coal, and also as oil and gas. There was an abundance of energy in
this carbon battery – and we have been gorging ourselves on it ever since,
while also increasing in population at an unsustainable rate. The most recent
expression of this excess is the glee of politicians and industry at the prospect
that even more gas can be accessed by fracking whilst ignoring the release of
yet more carbon into the environment.
Energy production that damages the environment
Left to itself, nature usually metes out harsh treatment when such excess
occurs in the animal kingdom – mass death through disease or starvation is
normal, a horrific outcome to anyone with a belief in the sanctity of life.
However, the sanctity of individual life has no role in evolution. Through the
exhortations of religion, a belief in rights and the pressure of law, mankind
has hoped that he might retro-fit the sanctity of life to nature as a principle –
but that is an illusion. In good times he is inclined to forget that if he does not
study and make the right decisions, nature – known as the Grim Reaper in
earlier times – will take those decisions for him without regard to the fate of
individuals.
If we are to stop exploiting the carbon battery, where might we find a source
of energy to replace it? The question is as momentous as the one that we
faced in prehistoric times when we adopted fire for our own use. The answer
is nuclear, but society worldwide will have to address some misconceptions
before it is likely to accept that.
The burning of coal, oil and gas release carbon dioxide into the atmosphere,
and the combustion of waste, biofuels and biomass do the same. In fact, to
make matters worse, because of the dioxide, the amount of carbon dioxide
released is greater than the weight of carbon burnt by a factor 44/12 = 3.7.
Our atmosphere is incredibly small and although it extends upwards from the
Earth's surface for several miles, it is very thin, just one kg above each square
centimetre, which means it does not take much to pollute it. Illustration 1 on
page 2 shows how every year since the start of the Industrial Revolution, the
concentration of carbon dioxide has risen far above values for the past
160,000 years. A basic description of why this increases the global
temperature is given in Chapter 3 of Radiation and Reason [see Selected
References on page 279, SR3]. Today, six years after that book was published
the concentration has risen to 400 parts per million (ppm) and there is
significant evidence that the average temperature, particularly in the Arctic, is
rising. Table 1 shows how the concentrations of other greenhouse gases have
also risen.
64 Chapter 4: Energy to Support Life
Concentration
(ppm) pre-1750
Concentration
(ppm) 2013
Lifetime in the
environment
Carbon dioxide CO2280 395.4 100-300 years
Methane CH40.722 1.893 - 1.762 12 years
Nitrous oxide N2O 0.280 0.33 121 years
Table 1: Atmospheric concentration of the most significant greenhouse
gases. IPCC data from http://cdiac.ornl.gov/pns/current_ghg.html
Methane is of particular concern because its greenhouse properties are more
pronounced than those of carbon dioxide. Although it is oxidised in the
atmosphere in 12 years on average, its concentration has risen by a factor of
nearly three, and much of that increase has occurred in the past 50 years [see
also Illustration 1 on page 2]. Significantly, there are large stores of methane
under pressure in the cold of the Arctic in the form of methane hydrates on
the seabed along the continental margins. These may become unstable as the
ocean warms, which would result in the methane being released into the
atmosphere. Methane is also stored in the soil under the Arctic permafrost,
and warming increases the likelihood of a positive feedback in the climate
system that releases this too [1]. The most recent reports from 2013 and 2014
suggest that these mechanisms may be acting faster than previously
supposed. There is evidence that methane is released in explosive events in
Siberia and that its concentration is rising much faster in the Arctic than
elsewhere [2, 3, 4].
The magnitude of the global warming effect is uncertain, but it will probably
not be known precisely until it is too late. The uncertainty relates partly to the
methane story, and partly to the role of the oceans and how fast they are
acidified by absorbing atmospheric carbon dioxide. This book is not
concerned with the Earth's climate directly, but it is the expectation of climate
change that makes its message urgent, and the consensus of the
Intergovernmental Panel on Climate Change (IPCC) supports that
expectation [5]. There is every reason to pursue nuclear energy to reduce any
impact of anthropogenic climate change. This is an appropriate use of the
Precautionary Principle: the extent of global warming is still uncertain and
there is no down side to this policy of taking the precaution now [6]. This may
be seen as an effective mitigation policy, although it may well take more than
a century for the atmosphere to begin to reach a new equilibrium, if there is
one.
Nuclear is for Life. A Cultural Revolution 65
Energy without harm to the environment
If we are to avoid nature's solution by catastrophe, we will have to start some
serious thinking about how life is lived and organised. This should go deeper
than simply replacing all fossil fuels. We should study all the disciplines that
enable us to live on a crowded planet, instead of lazily engaging in substitute
understanding by simply accepting the consensus opinions offered by
specialised committees. Generally these are not concerned to see how their
different perspectives fit together as a consistent whole. It is unlikely that
such consultant opinions played any part in the prehistoric decision to
domesticate fire!
Today, a decision to opt for nuclear technology should be informed by
evidence and education, and seen as much more clear-cut than the earlier
decision in favour of fire. There is essentially no danger to a vast deployment
of nuclear power to replace carbon fuels limited only by the speed with
which the required education can be provided. But without the education,
democratic mechanisms make starting such a major change difficult. If
civilisation is not to be overwhelmed by climate change, the choice may lie
between a loss of democracy for everybody and a new crash course in
science for many.
We have used energy to cook food, improve diet and extend life expectancy
through housing and better health. The wear and tear on the human body has
been reduced by mechanised transport by water, rail, road and air. In the case
of water and rail, there were many fatal accidents in the early days, but it was
not until the second half of the nineteenth century that the democratic voice
was raised in the name of safety. By the time that mechanised travel by road
became possible, more safety was demanded in all aspects of life.
It was important that, rather than banning a new technology, the necessary
education and training was provided, as earlier in the case of fire. Technology
has always made some places dangerous, but we all learn not to go there,
children included. Scare tactics similar to those used later for road traffic (and
today for nuclear energy) were deployed by conservative groups to stop the
introduction of railways as early as 1839, as shown in Illustration 18. In the
case of road traffic, what actually happened in the nineteenth century is
interesting. In the UK a series of restrictions was enacted culminating in the
infamous Red Flag Act of 1865. This reduced the permitted pace of steam
engines on the highway to walking pace, and required that a man should walk
in front carrying a red flag. The anti lobby who pressed for legislation was
concerned about accidents to pedestrians and frightening the horses, so they
said.
66 Chapter 4: Energy to Support Life
Illustration 18: A poster of 1839. A NIMBY (Not In My Back Yard)
scare about a new threat at the start of the railway era.
Nuclear is for Life. A Cultural Revolution 67
Later the development of the internal combustion engine and the need to
compete with industries in France and Germany provided strong incentives to
reconsider these restrictions. With hindsight we can see that modern
prosperity with its reliance on road transport would hardly have been possible
if the Act had not been repealed in 1896, even though safety concerns persist
to this day. The public know that safety restrictions on their own would give
insufficient protection in the event of a head-on smash. Drivers accept
personal responsibility to maintain their vehicles to an agreed safety standard
and stick to careful driving practices that prevent accidents.
Today, everybody accepts that as speeds are reduced, traffic accident rates
fall. But there is no call for all road traffic to move at a speed As Low As
Reasonably Achievable because that would take us back to the Red Flag Act.
The case of road traffic is interesting – when it began, there was a powerful
rail lobby anxious to protect their interests. Similarly today, there are large
fossil-fuel interests who have no reason to object to nuclear technology being
kept in check by stringent safety regulations – except, of course, in clinical
use for their personal health when radiation doses, thousands of times higher,
are welcomed by everybody.
If they had realised in time, the shipping companies with their luxurious
ocean liners might have challenged the safety of air travel in a similar way.
But they did not see the threat coming, and air travel was introduced
gradually by the airlines. The romantic era of travel by sea with its ability to
handle thousands of passengers must have seemed immune to a few
aeroplanes with a handful of daring travellers. But, by the time the shipping
companies realised that their business was threatened, it was too late.
Externalising the power to think
People have been much exercised by the uses and abuses of energy, but they
have had less concern about the consequences of externalising their mental
powers. In recent decades they have happily handed over many tasks in their
amorous affair with the electronic computer. Do they feel less threatened by
its power than by the power of the nucleus? Is this because society has not
yet had an existential accident with computers? The protection against
different forms of computer virus seem fundamentally weak when compared
to the physical and biological protection against a nuclear accident. Perhaps
the power of computers has seemed better hidden than nuclear power. But we
may come to regret that, by spending time worrying about nuclear, we have
neglected the safety of another power, our ability to think and solve
problems, that once was exclusively ours, and that we increasingly sub-
contract to silicon. Is this lack of vigilance just a matter of laziness, or an
inability to imagine a disaster unless of a type that has already occurred?
68 Chapter 4: Energy to Support Life
Energy for excitement and risk
Need for fun and stimulation
The human reaction to real danger is not simply one of horror and dread.
Quite the reverse: to make available the extra emotional energy to engage
successfully in dangerous situations, evolution has provided a sense of
excitement as a reaction to danger. It was important to the survival of early
humans that this sense of excitement or courage should be a positive and
enjoyable experience, without any deep rationalisation. Entertainment by
excitement is a basic human need; it exercises the adrenalin reaction in
readiness for a personal face-to-face encounter with real danger. Gladiatorial
combats, mediaeval duels, back-street cock fighting, bull fights and boxing
bouts, all these provided the ingredients of competition that excite an
audience, and the greatest excitement comes in a contest between the most
powerful, the champions. Safety, the protection from exposure to actual
danger, has improved for almost all humanity in the past century, thanks to
the application of science. Nevertheless the appetite for excitement is
undiminished especially when it can be enjoyed vicariously from the
reassuring safety of an armchair. Such is the nature of sport for much of the
population.
Modern technology has provided the means to offer stimulating
entertainment all day and every day – at its most exciting in the form of 24-
hour news, for which the outcome is unknown in advance. Modern news
media exist by sharing the excitement and thrill of speculation. Any
suggestion that a duel has an entirely predictable outcome is a most
unwelcome development for those whose business is selling stories that
excite. The exciting high that news generates is not related to any desire to
understand. The tsunami of the Great East Japan Earthquake of March 2011,
the biggest of modern times, was shown lifting up cars, boats, ships and
whole buildings, and carrying them far inland. The LPG store at Ichihara was
shown destroyed and on fire. These dramatic pictures played to worldwide
attention, as no other event could do, except the terrorist attack on the Twin
Towers in 2001. From a bar stool with a drink amongst friends, or from a sofa
with family at home, the excitement of an unfolding powerful physical on-
screen event with undisclosed outcome trumps any human contest or even a
historical epic, like that of Krakatoa in 1883, the largest explosion ever
recorded on Earth. There is nothing logical about this reaction to danger,
although it was necessary in primitive times as nature's way to make the task
of coping with real danger seem both positive and welcome, when in the cool
light of reality it is neither. Humans want to believe in dangers, especially if
they do not affect them personally, simply to provide such excitement. This is
why the world is reluctant to give up the story of Fukushima and accept that
Nuclear is for Life. A Cultural Revolution 69
in large part it is false.
The effect of news
Although an essential feature of nature, nuclear energy is frequently depicted
as man-made. The accident at Chernobyl (1986) was unseen by the world,
shrouded by the largest cover-up that the Soviet Union could mount in its
dying days. Among earlier nuclear accidents, the Windscale fire (1957) was
much smaller and largely covered up too. Three Mile Island (1977) produced
no dramatic pictures for the media. The action was hidden from view, inside
the reactor, the problem was contained and there was no disaster in the streets
to cause excitement. But Fukushima Daiichi (2011) was different. Everyone
saw the video of the reactors, apparently being overwhelmed by the wave and
the explosions at the plant; the cameras pictured the abandoned streets after
the evacuations and reported the panicked pronouncements of politicians, the
emptying supermarket shelves, the planes filled with frightened foreigners
running for home, and the men enveloped in protective suits and helmets
arriving by bus. There was no shortage of fear, for the people themselves had
seen the pictures; a fire-storm of reports about workers struggling and
reactors spewing fed on one another, day after day. The workers certainly had
a rough time, and at home their families were frightened for them; in many
cases they had lost homes and relatives, missing presumed dead, in the
tsunami. But soon things got even nastier for them, and their employers too,
as a whirlwind of blame broke over the news reports. The supposition that in
the event of an accident somebody must be at fault, and should be called to
account, is an easy one to make, even when invalid. But the resources of
nature available to create mayhem are unlimited and it is unreasonable to
think that they cannot overwhelm any man-made defence, as the earthquake
and tsunami of March 2011 did.
And something did not ring true in the extreme accounts of the nuclear
accident at Fukushima Daiichi. Nature seemed to be reading from a different
script. Was this a tragedy? Hamlet with no death? Nobody was reported to
have died from radiation, but somebody should have asked why not, as the
death toll remained firmly at zero. Pursuing the question and getting an
answer is not difficult. In fact, technically, it is quite straightforward and
simple to understand. However, the answer is unexpected to most people, for
it calls into question assumptions that they have lived with all their lives.
Learning new truths can be a positive experience, but it is hard to accept that
what you previously thought to be true is in fact false. Here in these chapters
there is sufficient explanation that the reader can decide for himself whether
the tragedy that did not happen at Fukushima Daiichi was a lucky fluke or
that nuclear radiation is not such a threat to life, even in an extreme case like
this.
70 Chapter 4: Energy to Support Life
How much does this matter? Many of the problems facing mankind need
energy, and surmounting misconceptions about radiation may be an important
task in the early twenty-first century so we should ensure that we get a factual
answer.
As for the media, they are in the business of engaging with personal
excitement and encouraging the collective behaviour that leads from rumour
to panic, and so selling copy. In the reporting of Fukushima they certainly
succeeded in doing that. Evolution ensures that people should be alert for the
Illustration 19: Diagram comparing probabilities
shown as circular areas.
Nuclear is for Life. A Cultural Revolution 71
unexpected, although in their modern affluent lives this appears to happen
less often and this worries them. Today the threat of nuclear war still
speaks to the current state of the world, a voyeuristic, tourist filled
culture where catastrophe is viewed as entertainment by increasingly
desensitised masses. The iconic mushroom cloud ... serves as a
metaphor for larger societal issues such as global warming, nuclear
power, industrialisation and pollution. Issues that seemingly breed
adopted apathy, where individuals can do little but stand by and
watch.
Clay Lipsky [7]
Separating high from low risks in life
To help reach a more stable view, individuals should distinguish the
long odds on some of the risks that they worry about. For other risks
with short odds, they should react by working towards solutions, even
when the problem is global. In life everyone is a player – there are no
real parts for spectators, however excited.
In Illustration 19 many such risks are compared in terms of the average
lifetime risk for an individual. For a start, the lifetime risk of death, somehow
and at sometime, is 100%, and this is drawn as a large circle at the top with
black outline. Some risks of death are drawn as red circles with areas in
proportion; the ones in green are not risks of death but other probabilities
shown for comparison.
It is not possible to show all such risks in this way because some of the areas
would be far too small to see. So a small area of the upper circle is shown
magnified a thousand times. Within it some probabilities of death in the range
1 in a thousand to 1 in a million are shown magnified. These causes of death
in this second circle are unusual today and are compared with the chance for
three people at random being born on consecutive days in the year.
But the probability of some causes of death are less than one in a million and
their circles would not be visible, even on this expanded scale. So in the
lowest black circle of the diagram probabilities have been magnified a further
thousand times, making a magnification of a million. This is used to illustrate
that, for all the people in the world in 1945, the chance of dying from
radiation-induced cancer from the bombs at Hiroshima and Nagasaki was less
than the chance that two people at random having been born on February 29,
the leap day. The chance of being killed by radiation at a nuclear power plant
is 50 times smaller still. It is indeed hard to comprehend how small these
risks are compared to other serious hazards that beset us.
Personal experience can be used to put the significance of these numbers into
further perspective. Everybody knows someone who died of cancer or heart
72 Chapter 4: Energy to Support Life
disease. Perhaps you knew, personally, someone who died in childbirth. But it
is unlikely that you knew someone who died in a plane accident or any of the
accidents described by the smaller circles. Even the largest nuclear risk is
seen to be minute compared with any of the conventional hazards shown. In
fact it is partly because nuclear accidents are so very unusual and unfamiliar
that they are newsworthy and carry extra dread – rationally, that is perverse.
Energy as frightening
Any source of energy able to replace carbon combustion has to be large and
powerful to do the job – and such a powerful agent naturally overshadows
any personal human effort. Such power may feel intimidating, but this
primitive reaction is mistaken. It is not size and strength that determine
whether an agent is dangerous; it is the relationship that we have with it, in
particular whether it is understood and trusted. So we expect a flu virus to be
more of a threat than an elephant, especially if we take the trouble to study
the elephant and get to know it. In general people are likely to feel threatened
by size and energy, whatever the technology, but it can be countered by
sympathetic education if that leads to familiarity and confidence – like
learning to drive a powerful car or watching others who are adept at doing so.
Just imagine, if you had never been driven at speed in a car before, it would
be an alarming experience.
Safety in a natural
disaster
A mix of personal training and
devolved individual judgement can
be very effective in mitigating the
effects of natural disasters too. The
earthquake and tsunami that struck
northeastern Japan on 11 March
2011 are an example. A long history
of major earthquakes has ensured
that Japanese building codes are
rigorously enforced, and on this
occasion the quake itself caused
remarkably little damage. Everyone
living in Japan has learnt about
earthquakes and what they should
do. Consequently they are calmer
and more able to cope when one
hits than would be the case in
another country The earthquake
triggered well-practised actions by
Illustration 20: Photograph of
Tsunami evacuation route
instruction seen in the pavement
[WWMA photo., Dec. 2013].
Nuclear is for Life. A Cultural Revolution 73
the population in anticipation of the tsunami and the after-shocks that
followed. Such instructions of what to do are to be found everywhere in
Japan – Illustration 20 shows a simple example seen in the street. At the time
of the quake, there were 500,000 people in the region that was subsequently
inundated [8, p. 41]. In the half-hour delay before the tsunami arrived almost
everybody found their way to higher ground or another place of refuge.
Schools were evacuated quickly following well-rehearsed plans. Inevitably
many of those who got caught by the tsunami were the elderly who were
unable to react so quickly. As of Sept 2012, 15,870 deaths were recorded with
2,184 still missing. It was an extraordinary accomplishment that 96% of
those endangered by the unprecedented inundation were saved in such a short
time. On previous occasions when a major tsunami had occurred in Japan, the
death toll had often been higher, but experience had taught the importance of
training and individual action. Such preparation is effective at giving
confidence and in making relatively unusual phenomena more familiar to the
population through practice and discussion.
Personal and national engagement with safety
However, when it came to the release of radioactivity the reaction was quite
different: nobody knew what to do or what to expect. The danger was
unfamiliar and its consequences unknown to almost the entire population.
The necessary education and personal confidence were absent at all levels in
society. In Japan and around the world, the collapse of confidence that ensued
was in sharp contrast to the total absence of fatalities – or even serious
casualties – due to the radioactivity itself. This near panic would not have
happened if the population and the authorities had had a similar personally-
informed awareness as they had when faced by the earthquake and tsunami.
What happened is seen by the Japanese people and their leaders as a failure
of both Japanese institutions and individuals [9]. However, only the
occurrence of the exceptional earthquake and tsunami were peculiar to Japan.
The absence of personal confidence in radiation and all nuclear matters is an
educational shortcoming that is equally serious in every country – a failure
that springs from a distaste for learning about a matter that is thought
unpleasant.
There is no man-made structure that cannot be overwhelmed by nature, and
investing in an attempt to ensure 100% safety is a waste of resources,
whether a sea wall against a tsunami or an ideal nuclear reactor. For the
nuclear case it would be cheaper and more effective to invest in public
education and some understanding of why nuclear technology is safe. That is
what has been done so successfully over the years in Japan as protection
against earthquakes and tsunamis. Regrettably, the Japanese people and their
authorities have not seen how to apply this lesson to their nuclear experience.
74 Chapter 4: Energy to Support Life
They have joined in a blind worldwide technical rush to increase physical
safety at nuclear power plants, either in anticipation of a popular loss of nerve
or in the expectation that safety standards would be raised even higher.
Such work is very expensive, but does it reassure? Unfortunately, the sight of
such large-scale protective measures being taken, in any context, only
confirms in the public mind that there must have been a miscalculated danger
in the first place. The conclusion is then reached that the public were
previously inadequately protected, for which they blame the authorities. This
raises the further thought – and then the rumour – that the danger might still
not be adequately estimated, even after such new protection is made. The
result is a lack of confidence that expands and feeds on itself. The
miscalculation appears in the media with accusations of incompetence or
cover-up, although that was never the cause of the problem. The real cause
was a total inability to handle the public perception of what happens, or
might happen in such an accident. But in Japan since 2011 there is nothing to
suggest that these lessons have been understood.
Another accident similar to Fukushima is unlikely, but should one happen,
there would again be no major health impact from the radiation. Any panic or
significant economic impact would be caused by a failure of training and
public information, unrelated to radiation safety – as in 2011. With the
appropriate preparation and trust, there would be no serious consequences, as
would have been true in 2011 if the Japanese authorities had only read the
reports from Chernobyl and shared the information with the people in a
programme of public education [10, 11]. This criticism is aimed not just at
Japan but at every country that panicked. The lesson of Fukushima is
universal and it has not been helpful that each nation has internalised its
reaction, allowing it to become a matter for local political controversy and
debate.
Education and democracy
In the usual way that history develops, the next major accident will be
different from the last, so for any lessons learnt to be useful they should be
seen in the broadest terms. If human life on Earth is to be sustainable for ten
billion people or more with the benefits and aspirations needed for political
stability, we will have to cooperate more than in the past. This will not work
effectively unless individuals feel personally and democratically engaged.
Future economic progress that provides stability and jobs for an increasing
population depends on science and its applications, as it has since the start of
the Industrial Revolution. Confidence and informed decision-making will not
be forthcoming unless the science is adequately understood by sufficient of
the population to engender trust. Without trust, democracy does not function
effectively and society becomes unstable.
Nuclear is for Life. A Cultural Revolution 75
The present habit of authorities faced with scientific questions is to call upon
experts to whom understanding is subcontracted – this is ineffective. It
provides neither the right broad answers, nor does it build trust. Only
personal understanding built on deep education and spread through the
population, however thinly, can do that. Without such foundations decision-
making is easily influenced by groups built around those who are simply
frightened, do not understand the science or have lost confidence in the
authorities. Over time such groups build up funds and staff with their own
careers and mortgages. These then have a personal interest in fomenting
distrust for as long as funds continue to roll in to the group.
A Babel of disciplines and conflicting interests
Education in different logical voices
The various disciplines involved in making decisions about energy and
nuclear radiation are strangers to one another. They are all open to study, but
in a traditional education young people are rarely brought up to establish any
personal confidence in more than a few of them. This compartmentalised
understanding then persists for the rest of their lives – and that is only for
those few with an educational background of any relevance at all. This is an
unfortunate omission in the structure of education, because these various
disciplines are remarkably different and there is a need for people to
understand how they relate to one another in the areas where they overlap.
This is a call for an appreciation of the different perspectives of physical
science, medicine, biology, social and economic science. Each may be
coherent and logical in its own sphere, but reconciling them with common
sense is important.
None of the disciplines is a no-go area to anyone ready to study and reach
their own conclusions. Each field has its own intellectual ethos and reasons
for it. But there are other more questionable pressures at work too – like the
perceived need to defend jobs, career status and professional territory, to
maintain budget allocations and to realise a return on previous investment.
Physical science and linearity
In the basic physical sciences the universe is portrayed as surprisingly simple.
The descriptions that turn out to be correct are often symmetrical and seen to
be more beautiful than the alternatives: being correct in physical science
means being able to describe with a few fundamental principles and to
predict, unfailingly and precisely. Admittedly there is no reason why physical
science and mathematics should have such power, but as time goes on there
are ever fewer situations in which they do not deliver.
76 Chapter 4: Energy to Support Life
Symmetry is an important paradigm in the account that physical science
gives of the physical world. An inflated party balloon forms itself into a
perfect sphere, and so too does a soap bubble. The material of the balloon and
the film of a bubble are symmetrical and uniform. If that is not quite true, the
difference in shape can be calculated from the extra rubber around the
entrance pipe of the balloon or the weight of the drip of excess liquid hanging
on the lowest point of the bubble. The near-perfect shape is delightful to child
and scientist alike. In fact symmetry is a big subject and sometimes a curious
one. Are left and right the same, only different? Similarly, forward and
backward in time? What about different places or different times?
Uniqueness is another paradigm. In physical science a well-defined question
usually has a single unique answer which is distinguished by its economy of
expression – mathematical physicists see this as beautiful. A particular
problem has just a single answer, but this is not true in biology, and in fact,
uniqueness and symmetry play little part in most other disciplines. So the
question is whether the same is true of every principle that is highly
significant in physical science and mathematics. In particular, does linearity,
an important (though not universal) principle in mathematical physics, apply
in biology, in particular to the health effects of radiation?
We should explain what linearity means. For example, linearity usually
applies to the way that waves behave, like the sound waves from each
instrument in an orchestra. Although these are sent out into the concert hall
all on top of one another, they seem to act quite separately, allowing the ear
to distinguish the waves from each instrument, as if the others were not
present. This is not a special ability of the ear – it applies to everything
affected by the sound, unless the sound is actually distorted. When a number
of causes and their respective effects add together in this way, the behaviour
is linear, and then apparently complicated things become much simpler to
calculate, easier to visualise and think about. It makes the physical world
describable, like a structure of LEGO bricks, put together piece by piece.
But even in physical science, not everything is always so easy; there are
many cases where linearity does not apply, for instance to the turbulent flow
of liquids and gases where following the relationship between cause and
effect is much harder. The atmosphere, and so the weather, involves such
turbulent flow, and these non-linear aspects make predictions more difficult.
So scientists welcome linearity when it applies. Indeed much of mathematical
science is concerned with searching for ways to see behaviour in linear terms,
either exactly or as a series of converging approximations which make
calculations and predictions possible. But scientists need always to keep a
sharp eye open for situations in which cause and effect are not related in this
way. Pretending that something is linear when it is not is just wrong and can
lead to dangerous misconceptions – as in the health effect of radiation doses.
Nuclear is for Life. A Cultural Revolution 77
Linearity. If a cause X has an effect x when applied to a system, and a
cause Y has an effect y, then what happens when causes X and Y are
applied together, that is X+Y? If the effect is x+y, the effect is linear, and
the responses to X and Y are independent. If the effect is anything else, the
response is non-linear. Simple but very powerful, as it turns out.
Special case: If the response is linear, cause X+X will give effect x+x; and
X+X+X, will give effect 3x; etc., and then the cause-effect relation is a
straight line, as sketched in Illustration 21 on page 79. But it is a mistake
to think that linearity is just about the dependence of an effect on its cause
being described by a straight line rather than a curved one.
Suppose the occurrence of lung cancer is linearly related to its causes. If X
is smoking as a cause and Y is radiation as a cause, then the cancer
resulting from both together would be the cancer caused by smoking plus
the cancer caused by radiation – that is x+y. But the analysis of lung
cancer in populations exposed to smoking and radiation, in particular
radon, the radioactive gas in the air, shows that this is not true. According
to the data available, smoking on its own is about 25 times more
carcinogenic than not smoking, and only in the case of smokers is there
any evidence for extra carcinogenesis due to radon. So these causes of
cancer are not independent, and so non-linear .
Conventional analyses of radon, smoking and lung cancer use the so-
called Linear No-Threshold (LNT) model. This is a non-linear method
called relative risk. The data do not show linearity and these analyses fail
although they falsely conclude that radon is responsible for much lung
cancer. This is discussed in more detail in Chapter 6.
Why does basic physical science so often enjoy the benefits of
symmetry, uniqueness and linearity? The answer to this philosophical
question is unknown. It is no answer to point out that, otherwise, the
physical world would be more irrational and harder to describe. The
world might indeed be inexplicable and unpredictable. In fact many in
the world do not understand science and see exactly such an
inexplicable world. Such people have to build confidence exclusively
on a foundation of trust and belief, and that may be fragile and
inflexible in the event of change. That is the reason to protect young
children: their judgement and confidence lacks the stability that comes
with education and experience. Without confidence the world can seem
frightening. Engineering and technology are built upon the
predictability of the world, and exploit it through mathematics and
physical science whenever possible. Naturally, technology inherits this
78 Chapter 4: Energy to Support Life
logicality and simplicity, and to scientists and engineers the physical
world often seems less dangerous and more predictable as a result.
Therefore scientists should explain and share, as best they can, while
respecting that others may doubt the confidence that physical science
provides.
Biology, medicine and the logic of evolution
Although all of its components are simple and physical at an atomic level,
life has not been designed using the principles of physical science in the way
that the design of a car, bridge or electronic chip might be. It is not simple,
symmetrical or unique, but is designed to survive and thrive within a certain
range of conditions. Life is a product of evolution, and whenever conditions
change the design gets modified too, otherwise it is liable to suffer a
disadvantage. Actually, it does not get modified in the way that a computer
gets updated by downloading a suitable patch: rather, it effectively modifies
itself. As Darwin demonstrated, the design of each species and sub-species
evolves locally to match the particular history of survival threats that it has
recently experienced. This means that scientific logic, as understood in the
biological and medical sciences, looks very different from that in the physical
sciences. Each life form is a solution to a local problem and has no general
reality at other times or places, unlike the prescriptions of physical science
which apply at all times and in all places throughout the universe. The
solution to a biological problem of survival, rather than being remarkable for
its simplicity, as a physical science answer might be, is likely to be
remarkable for its complexity.
These differences stand out strongly in a description of the effect of radiation
on life. This happens in two stages: in the first, the radiation disrupts the
atoms and molecules of which the living tissue is made. This is a matter for
physical science and is typically linear – the initial damage is in proportion to
the energy absorbed in the living tissue, as sketched in Illustration 21. The
second stage is the story of how that tissue responds to the trail of broken
molecules, if it is alive – this is a biological question concerned with the
ability of cellular life to survive an attack. This is not at all linear, as will
become clear in Chapter 8. In fact the assumption that the net effect of
radiation is linear, just because the initial damage is linear, is the basic
mistake responsible for the mishandling and misery of the Fukushima
accident – and of Chernobyl before that. It is the crux of the message
discussed in this book.
Nuclear is for Life. A Cultural Revolution 79
So the basis of the physical sciences and of the medical and biological
sciences look sharply different for good reasons, but few scientists are
familiar with both types of discipline. Consequently, physical scientists and
engineers, though able to follow the physical behaviour of radiation, treat the
behaviour of living tissue with great caution, it being quite unfamiliar. Most
medical scientists are quite unfamiliar with quantum mechanics, where the
fundamentals of nuclear physics are played out, though they are respectful of
its powerful effects. In clinical medicine the priority is the well-being of the
patient, and that comes before concern for the environment. Certainly
clinicians are not eager to explain that the radiation dose to be used is tens or
even thousands of times higher than any dose received in the environment –
that might upset the patient and discourage them from accepting treatment
that is clearly in their best interest. So many clinicians distance themselves
from discussions of radiation doses in the environment, although they have
been improving health and saving lives using moderate and high radiation
doses ever since Marie Curie pioneered such work a century ago.
As a result the effect of radiation on life has been treated with unusual
caution, even amongst scientists on both the physical and biological sides.
This has suppressed the spread of a scientifically robust account, transparent
and easy to understand for all concerned. Such an account should be written
and explained. Instead, the story has appeared confused, for the political and
historical reasons discussed in Chapters 9 and 10.
On the biological side, a unanimous joint report was published in 2004 by the
French Académie Nationale de Médecine and Académie des Sciences [12] that
Illustration 21: A sketched graph showing the linear way in
which the immediate damage from radiation depends on the
instant radiation dose.
80 Chapter 4: Energy to Support Life
set out a full academic case for a complete change in the regulation of
radiation. However, this was written in professional language and never
reached the public. As a result it has been effectively suppressed and not yet
acted upon. Following the Fukushima accident, international professional
opinion is pressing anew for public scientific and legal standards that accord
with modern radiobiology [13].
General public and common sense
Most members of the public are nervous about nuclear power and radiation.
They are aware that it involves a very powerful agent that they do not
understand and so they suspend their common sense and confidence, thinking
that they would not give them useful guidance. That is unfortunate. They are
worried by the connection to nuclear weapons, but this is wrong – just as
associating a log fire with the explosion of dynamite because both are
chemical processes would be wrong.
Such misunderstandings have persisted for 70 years and public apprehension
of nuclear technology has been exploited in international politics to apply
diplomatic pressure to regimes in various ways. As the decades go by, the
number of states which have sufficient resources to build a nuclear weapon
but have not done so continues to rise. Weapons technology is far more
demanding and expensive than civil nuclear power (access to which is
internationally available), and the leaders of most countries have realised that
it would be a waste of resources and valuable manpower to develop a weapon
capability [SR4]. While super-powers attempt to dictate who may eat the
forbidden fruit of nuclear technology, the public remain ignorant of the
science and do not know whom to trust, particularly in those countries with a
living memory of being on the front line, like Germany and Japan. In other
countries, the public have recently understood that civil nuclear power may
be a means to mitigate climate change and so they support the use of nuclear
power as the least bad option. But others oppose it, remembering how much
they were frightened by the threat of military and political nuclear forces at
the time of the Cold War and seeing no reason to repeat that experience.
Universally, people are curious to know more and are ready to discuss the
issues, preferably with someone whom they trust, even while disagreeing
with them. They refer belief and disbelief in nuclear power, as if it were a
religion. They seek someone to trust on the subject, while they learn to look
at the evidence themselves and come up with their own judgement – at least
that is the hope, and, anyway, the only sure way to build confidence.
Education and trust are critical and it is noticeable how young people are
more open, not having personally experienced the threat of the Cold War. But
they should think it out again for themselves, and they need the opportunity
for open discussion.
Nuclear is for Life. A Cultural Revolution 81
Parents take particular care over risks to children, and it is important and
natural that they do so. However, authorities should not respond with
radiation regulations that are more protective for children, unless it is shown
that they are at greater risk. The question whether children are at more or less
risk than adults from a given radiation dose is a biological and medical
question, not a family one. If family concern, which is quite properly
exercised by parents, becomes confused with the biological judgement,
caution gets piled on top of caution, without limit. Such multiple caution has
been responsible for children near Fukushima not being allowed outside to
play in low radiation environments, when it would clearly have been in their
interest to do so.
In some respects, children are more at risk than adults and in others, less.
Around Chernobyl, some increase in thyroid cancer amongst children was
caused by the ingestion of radioactive iodine, whilst adults were largely
unaffected. On the other hand, the immune system that protects against pre-
cancerous cells is in general more vigorous in young people including
children. It is older adults with their weak immune system in their declining
years that are most susceptible to cancer. Cancer among young people is
newsworthy because it is relatively unusual, but among the elderly it is not
considered remarkable.
It does not seem appropriate that regulations should be pre-loaded with extra
medical concern for children without clear evidence. Parents will show extra
concern for their children anyway, as they should – but that is family care.
Regulations that adopt a parental role can result in overly worried parents and
overly protected children. In any case, public policy and regulations have to
be built on trust which can only come with education. When this fails, as
happened in Japan, children get kept in doors instead of going out to play.
Committees that ensure caution
Politicians have the task of matching energy with other elements of public
policy to the satisfaction of the electorate and the requirements of industry. In
this they may be watched over by a parliamentary committee whose numbers
might include an economist and several lawyers but rarely anybody with the
scientific confidence to reach their own independent judgement of the
choices to be made [SR9]. They work with models of human behaviour and
resources, shaped by inherited historical views and pressures from the
electorate. Faced with a more challenging technical question they look
elsewhere for authority and guidance from experts. If these are not available
and the committee lacks confidence, an international body may be consulted.
Such a structure fails to make the required timely decisions in four respects.
•Emergency decisions may be needed in a day or two, but such
82 Chapter 4: Energy to Support Life
committees can take years to reach a conclusion [14, 15], even when
useful and timely conclusions can be drawn in a few days from early
data and some basic knowledge [SR8]. Curiously, nobody remarks on
the unnecessary delay and its serious effects.
•The remit and membership of an international committee are
focussed in one technical direction. They are prevented from
responding to a broad crisis that stretches beyond the span of their
terms of reference. For instance, the United Nations Scientific
Committee on the Effects of Atomic Radiation (UNSCEAR),
established in 1955, is concerned with the effect of radiation itself. It
is unable to respond to the social, psychological and educational
consequences of the radiological regulations, as applied at
Fukushima, for example. The economic and climatic effects of
closing power stations and burning imported fossil fuel are beyond
the committee's scope too. It was nobody's job to comment on the net
response to Fukushima. That, not the effect of the radiation, was the
human disaster.
•When a committee has to answer a question, the judgement of
individuals, however able they may be, gets compromised by the
need to reach a consensus. This averaging obstructs change,
especially where members lack knowledge and confidence. The
larger the committee, the greater this effect is, so a large international
committee is very unlikely to recommend more than glacial change –
the speed of decision is slow and each step change piecemeal. In the
rare case that a committee chairman is able to overcome this
tendency, then he himself would have been a better and faster source
of opinion. The likelihood that such a committee would rethink a
basic attitude, in this instance, towards nuclear radiation, seems
regrettably small. So even with much goodwill, the guidance that
politicians receive is heavily weighted to the status quo and can
evolve only on a time scale of many years. Few people make this
point but it can be otherwise, given leadership. The part played by
Richard Feynman as a member of the Rogers Commission on the
Challenger Disaster was an exceptional example [16]. The report was
published five months after the accident in January 1986 with
Feynman's contribution, a triumph of clear investigation in the
tradition of Sherlock Holmes [17].
•Over time, a committee can become institutionalised with its own
traditions and self-interest that reduce its readiness to consider
change and make it slow to respond to any new challenge.
These shortcomings of expert committees act against the public interest, and
Nuclear is for Life. A Cultural Revolution 83
the large number concerned with radiation safety are no exception. But major
change can only be expected when a sizeable fraction of the population sees
that energy policy is headed in the wrong direction. The price of a successful
democracy is that people should understand the decisions they make.
Otherwise democracy is a loose cannon, with decisions based on random
unexplored ideas. How long would it take to accomplish such an educational
challenge? We have to press hard for it – there is no other way. Certainly,
children and young people engage with the subject easily and discussion is
very lively, though many of their teachers start with misconceptions that date
from when they themselves were educated. The science is not difficult – the
hard part is building trust and confidence, and, as with so many other aspects
of human activity, that comes best through personal enthusiasm and face-to-
face contact.
The public can show themselves to be brighter than media presentation
suggests. The speed with which the ban on smoking was adopted and spread
around the world gives room for hope. So too does the way in which the
Japanese people have learnt to live with the dangers of earthquakes and
tsunami. Given proper education and trust, they will respond, but so far this
has not happened for nuclear radiation.
Industry and its search for business
The nuclear industry has an interest in presenting a justified view of the
contribution that nuclear energy can make to future energy supplies.
Unfortunately its voice is often seen by the public as compromised by an
involvement in the technology that built nuclear weapons in the past, and by
financial self-interest in the present. Weapon development for national
defence programmes in the Cold War period was frequently hidden within
projects advertised as energy production – and that has not been forgotten.
Although today's power plants are designed, built, regulated and run by
international, not national, concerns, most individuals in the industry feel that
they have no voice and that the public at large sees their personal opinion as
compromised, and so they keep silent on the main issue. In addition, although
they are naturally the best informed on the physics and engineering hazards,
they rarely have any knowledge at all of what modern radio-biology has to
say about the health impact of ionising radiation.
Wider industrial interests, that is management and shareholders, are not
concerned to question the basis of safety regulations. Their interest is to
secure profitable long-term business for the investment they make, in spite of
the changes to regulations and the financial restrictions imposed to fix
concerns expressed by politicians and the press. To protect its financial
future, industry is always ready to build or decommission whatever the
market will pay for, even if the price is unacceptably high when eventually
84 Chapter 4: Energy to Support Life
charged to the consumer's utility bill, as it will be. The cynical politician,
faced with groups of professionally organised demonstrators, may think that
the impact on the consumer will be sufficiently far in the future.
Many environmentalists have engaged in some serious thinking, as expressed
in books and films [18, SR6, 19] and have now joined the call to expand
nuclear power as soon as possible. The rump of anti-nuclear demonstrators
are not well informed and prefer slogans to any discussion of medical or
scientific facts [20]. The politicians should realise that the demonstrators are in
retreat, their case being unsupported by sustainable evidence; and the media
who like a debate to be two-sided should appreciate that pitching fear against
science is not two-sided – it is irresponsible.
Overseeing and applying regulation of nuclear radiation safety is itself an
extensive responsibility. Those who have built careers and status in this
international business, with authority handed down from the United Nations,
do not take kindly to studies that demonstrate this activity to be over-egged or
quite unnecessary on its current scale. Naturally they resist vigorously any
radical change that would upset the present structure, most of them preferring
to stick with a religiously observed faith in a conservative view of safety. The
cost of this safety provision is an unjustifiably heavy burden for which the
consumer pays in one way or another. Those few in the safety business who
have kept up to date with the science, not just the regulations, ought to be in a
position to guide and contribute towards the re-education required.
Historical view
In retrospect, much of the development of nuclear technology was tainted by
the spirit of the time. The political and military pressures of the Cold War
period had a pronounced effect on the way nuclear energy was viewed and,
unfortunately, that is still true today. Published papers in the best journals
should be seen as trustworthy, although under exceptional conditions this
may be compromised. In the period in which massive numbers of nuclear
weapons were accumulated on both sides during the Cold War, some senior
scientists yielded to the extreme pressure: a story that is told in Chapter 10.
Their concern became the established view that nuclear radiation is injurious
to health, although this is untrue. A broader historical account is given in the
book by John Mueller [SR4].
Other fauna and flora
But there are others with whom we share the planet and whose interests
should be respected. After the Chernobyl accident, it was generally supposed
that with genetic changes, if not high death rates, plants and animals would
be severely affected in the evacuated region around the remains of the
reactor. They have been affected, but in a quite different way. They are
Nuclear is for Life. A Cultural Revolution 85
radioactive, but spared the human population, they seem to enjoy a new
freedom [21, SR7]. The evacuated area around Chernobyl has become a de
facto nature reserve with many species re-established and thriving. Evidently
the wildlife is better off now, radioactive and without humans, than it was
before the accident, not radioactive but hemmed in by humans. There are two
lessons here: firstly that the human race has monopolised the planet at the
expense of other forms of life; secondly, that the prevailing view that nuclear
radiation as deadly is simply wrong. This is surprising: Chapters 5 and 6
provide more insight into the nature of radiation and further evidence of its
effect on life; Chapters 7 and 8 explain the science that protects life from
radiation.
Notes on Chapter 4
1) Methane Hydrate Instability/ Permafrost Methane IPCC (2007)
https://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch8s8-7-2-4.html
2) Methane Hydrates and Contemporary Climate Change Ruppel USGS (2011)
http://www.nature.com/scitable/knowledge/library/methane-hydrates-and-
contemporary-climate-change-24314790
3) https://robertscribbler.wordpress.com/2015/03/09/cause-for-appropriate-concern-
over-arctic-methane-overburden-plumes-eruptions-and-large-ocean-craters/
4) note deleted
5) Fifth Assessment Report (AR5) IPCC (2015) http://www.ipcc.ch/
6) By the same criteria the application of the Precautionary Principle to nuclear
technology is unjustified: nuclear technology is understood and mature, and the
downside of not using nuclear endangers the environment and the capacity of the
Earth to support its growing population.
7) C Lipsky Atomic Overlook (2012) http://atomic-overlook.com/series.html
8) Lessons from the Disaster Y Funabashi et al, Japan Times (2011)
9) Nuclear Accident Independent Investigation Committee Report to the Japanese
Diet (2012) http://warp.da.ndl.go.jp/info:ndljp/pid/3856371/naiic.go.jp/en/
10) Health Effects of the Chernobyl Accident, WHO (2006)
http://whqlibdoc.who.int/publications/2006/9241594179_eng.pdf
11) New Report ... on Chernobyl, UNSCEAR (28 Feb 2011)
http://www.unis.unvienna.org/unis/pressrels/2011/unisinf398.html
12) Dose-effect relationships and...Tubiana, M. and Aurengo, A. Académie des
Sciences & Académie Nationale de Médecine. (2005)
http://www.researchgate.net/publication/277289357_Acadmie_des_Sciences_Aca
demy_of_Sciences-
_Acadmie_nationale_de_Mdecine_National_Academy_of_Medicine
13) Correspondence and articles posted by Scientist for Accurate Radiation
Information (SARI) http://www.radiationeffects.org See also Chapter 12.
14) WHO report on Fukushima (2012)
http://whqlibdoc.who.int/publications/2012/9789241503662_eng.pdf
86 Chapter 4: Energy to Support Life
15) UNSCEAR report on Fukushima (2013)
http://www.unscear.org/docs/reports/2013/13-85418_Report_2013_Annex_A.pdf
16) Rogers Commission on the Challenger Disaster (1986)
https://en.wikipedia.org/?title=Rogers_Commission_Report
17) Feynman's analysis of the Challenger Disaster (1986)
http://science.ksc.nasa .gov/shuttle /missions/51-l/docs/rogers-
commission/Appendix-F.txt
18) Nuclear Energy for 21st Century James Lovelock (2005)
http://www.jameslovelock.org/page12.html
19) Environmental and other academic support for German nuclear power (2014)
http://maxatomstrom.de/umweltschuetzer-und-wissenschaftler/
20) A video that challenges Helen Caldicott, McDowell (2014)
https://www.youtube.com/watch?v=Qaptvhky8IQ
21) National Geographic on tourism at Chernobyl (2014)
http://ngm.nationalgeographic.com/2014/10/nuclear-tourism/johnson-text
Nuclear is for Life. A Cultural Revolution 87
Chapter 5: Absorbed Radiation and
Damage
Be less curious about people and more curious about ideas
Marie Curie
Sources of ionising radiation
The discovery of radioactivity 88
Charged particle and electromagnetic radiation 88
Radioactivity as a source of radiation 89
Carbon-14 – an example of radioactivity 90
Potassium-40 and tritium 91
Atomic analogues 92
The electromagnetic spectrum 93
Linearity and its applicability
Initial radiation damage 95
LNT model of long-term damage 95
Failure of LNT model for live tissue 96
Quantifying absorbed radiation
Radiation doses and radiation dose rates 97
Measurement of radioactivity in becquerel 99
Finding a dose rate from a measurement of radioactivity 100
Natural internal dose 102
Other sources of natural background radiation 103
Food regulations at Fukushima and Chernobyl 104
Water release at Fukushima 105
Dose rates from external radioactive contamination 106
Comparison of ionising and non-ionising radiation 108
Safety and sunshine 110
What happens to radiation in materials
Range and the hit probability 111
Lack of discrimination in radiation damage 114
Role of oxidants in damage to living tissue 115
High LET radiation 115
Detecting radiation
Natural detection in living tissue 116
Detection with man-made instruments 118
Notes on Chapter 5 120
88 Chapter 5: Absorbed Radiation and Damage
Sources of ionising radiation
The discovery of radioactivity
When in 1896 Henri Becquerel discovered radioactivity by the radiation it
emits, what did he actually observe? He had been looking for radiation
emitted by crystals of different salts after exposure to sunlight – called
fluorescence. He took a photographic plate, wrapped it in thick black paper
and placed it underneath a pierced metal screen with the salts on top. On 26th
February and the following days the sun did not shine so he abandoned the
experiment and put the plate and salts away together in a dark drawer. On 1st
March he developed the plate expecting to find no more than the faintest
silhouette of the screen on the plate. What he found were very strong images
of the screen, as he reported on the following day. Evidently the sunshine
played no part so it could not be the result of fluorescence. Somehow the
salts were emitting rays that had an effect on the photographic plate like X-
rays, but normal X-rays need a source, an elaborate apparatus supplied with
electrical energy. Since there was none he described the salts as the source of
radioactivity. Whenever energy seems to appear or disappear without
apparent cause, physical scientists get excited. Something quite new must be
occurring, and indeed this was the case.
To anyone not already familiar with it, radiation may seem as mysterious
today as it was to Becquerel all those years ago, but now we know that it is
more a part of everyday experience than was realised. The word radiation
covers any kind of energy on the move, often spreading out from a small
region where it starts, that we call its source. It could be a sound wave from a
musical instrument or someone speaking; or a radio wave transmitted by a
mobile phone; or a water wave from a moving boat. These may seem
relatively innocuous, but that depends on how big the various waves are. A
tsunami wave whose source is the sudden movement of an area of ocean
floor is just a water wave, but sufficiently large to be damaging, especially
when it reaches the shore. Similarly, sound waves can be so energetic that
they break when they reach human tissue – like water waves on a beach,
dumping all their energy. Such sound waves at high frequency can be used to
break kidney stones and to treat cancer tumours. So weak waves are harmless
and strong waves of whatever the kind are damaging.
Charged particle and electromagnetic radiation
However, the radiation that Becquerel detected, often described as ionising or
nuclear, is neither a sound wave nor a water wave. Three varieties of these
waves are to be found in the environment, called alpha, beta and gamma.
Alpha and beta are streams of charged particles: for alpha the particles are
helium nuclei, helium is the gas used in party balloons to make them float
Nuclear is for Life. A Cultural Revolution 89
upwards; for beta the particles are fast electrons. The third variety, gamma, is
an electromagnetic wave (EM) exactly like light, only more energetic. But
that description is a bit sloppy, because for all radiation, including light,
surprisingly, the stream of energy is built up in two ways: the number of bits
of energy and the energy of each bit. For alpha, this is the number of helium
nuclei and the energy each carries. Likewise for beta, there is the number of
electrons and the energy of each electron based on its speed (its kinetic
energy). Light and gamma radiation are similar; each bit is called a photon, or
a quantum (after the Latin for how much). So there is the energy of each
quantum and the total energy of these, added up. How the light behaves,
including its colour, depends on the quantum energy. A quantum of red light
is half the energy of a quantum of blue light, whereas a quantum of X-ray is
more than a thousand times greater – and of gamma rays even more. The total
energy gives the brightness. This is a little like the energy of a river that
depends on how much water is flowing and also how fast it flows.
Radiation is called ionising if each individual photon or charged particle has
enough energy on its own to break or ionise a molecule when it hits it. This
does not depend on the total brightness, only on the energy of each photon or
electron. Einstein's paper of 1905 gave this explanation using the quantum
theory of light, for which he received the Nobel Prize in 1921. Note that this
quantum theory is over a hundred years old and thoroughly established,
despite often being described in popular media accounts as if it were
mysterious and controversial.
Radioactivity as a source of radiation
The radiation that we just described, like X-rays or light rays, is delivered in
an instant at the velocity of light and effectively travels in straight lines. It is
transitory, passing through and only leaving a persistent effect if it dumps
energy at some point. When it does so, it leaves damaged atoms and
molecules, and these are what we need to study – it is this damage alone that
can affect life. Radiation that passes through a body without dumping any
energy is harmless.
The vague term radiation as used in popular media often confuses the
radiation itself and radioactivity. Radioactivity refers to atoms liable to emit
radiation, like those in Becquerel's salts. An unstable radioactive atom is
almost indistinguishable from a regular quiescent one, except that it emits
radiation just once at some random point in time – after that, it has lost its
energy and cannot emit that radiation energy again. This randomness in time
may appear to suggest that something is unknown. But this is a general
feature of modern physics, known as quantum mechanics, that tells us very
precisely the probability of decay per second, but not the time when an
individual nucleus will decay. Each nucleus decays, emitting radiation in the
90 Chapter 5: Absorbed Radiation and Damage
process and leaving behind a different daughter nucleus (this is often stable
but in some cases may be radioactive in its own right). Because each unstable
nucleus carries the extra energy to decay once, in a collection of atoms at a
given time the number of nuclei available to decay includes only those that
have not already decayed. In this way the number decaying falls
progressively giving the famous exponential decay curve. The half life is the
time for half of the atoms to decay, so after three half-lives only an eighth
remain, and after ten half-lives only a thousandth remain (1/1024, to be
precise), and so on.
Carbon-14 – an example of radioactivity
An example of radioactivity is radiocarbon, that is carbon-14. Most carbon
atoms are carbon-12, and carbon-14 behaves identically in all but two
respects. Firstly it has two extra neutrons in its nucleus so that it is heavier in
the ratio 14:12, but this has little effect. Secondly it decays randomly at a
steady rate, such that half the nuclei turn into nitrogen-14 in a period of 5,700
years.
Every year a tiny amount of fresh carbon-14 is produced by cosmic particles
hitting the upper atmosphere, and this gets mixed in with normal non-
radioactive carbon, so that every growing or living thing has about one
carbon-14 atom for every 1012 carbon-12 atoms – but coal and oil do not,
because having been buried for many millions of years all carbon-14 nuclei
have decayed long ago. As soon as living things die, they stop eating or
growing and their proportion of carbon-14 starts to fall. In fact, we can
measure how old they are from how much carbon-14 remains, and this is how
radiocarbon dating works. It was used to measure the age of the Turin Shroud
that supposedly dated from the time of Christ, but was shown to be much
younger (1275-1290 AD) [1]; then there is the record of the Ice Man frozen in
an alpine glacier for 4,000 years [2]; carbon dating can also be used to spot
fake vintage wines and whiskeys, if the contribution from nuclear testing,
described in Chapter 10, is taken into account [3].
If you are not measurably radioactive because of the carbon-14 you contain,
any archaeologist can assure you that you have been dead for over 50,000
years. To that extent, it is healthy to be radioactive and certainly nothing to
worry about. So we may calculate how radioactive each of us is.
Nuclear is for Life. A Cultural Revolution 91
Call it roughly 50 becquerel per kg – a becquerel (Bq) is a measure of
radioactivity equal to one decay per second. So 50 decays per second for each
kg of weight – that would be about 3,500 clicks per second on a counter, if
that were able to detect every single emission of radiation in your body
(taken as 70 kg). Actually the beta radiation from carbon-14 decay is an
electron with very short range, so very few would reach the instrument and
few clicks would be measured.
Potassium-40 and tritium
There is another source of radioactivity within everyone's body, potassium-
40, which emits radiation with higher energy that goes further and is easier to
detect. What this radioactivity is doing in your body is an older story that we
will come back to later in this chapter. This adds another 61 Bq per kg
making a total of about 7,400 Bq in an adult body, meaning 7,400 nuclear
disintegrations per second. But this cannot be dangerous because it has been
so since life began. The point is that radioactivity is just a latent source of
radiation – radiation with delayed delivery spread out over a period of time.
Is it more hazardous for being delayed, or less so? As we shall find in
Chapter 6, it is actually less so.
Tritium is a radioactive isotope that has been in the news from Fukushima. It
is an isotope of hydrogen with two neutrons that would normally be called
hydrogen-3, but has acquired a special name of its own. However, until it
decays, it behaves exactly like the other isotopes of hydrogen, including
deuterium or hydrogen-2, except that it is heavier and so more sluggish in its
normal reactions. Concern about tritium has formed part of the media story at
Fukushima. As it happens, tritium is a product, both of the nuclear fission
process itself and of hydrogen (in water) catching extra neutrons, although
neither process can occur in a reactor that is turned off. How hazardous is a
dose of tritium? (The measurement of doses in milligray (mGy) is described
below on page 97.) The effect of a radiation dose rate in mGy per month to
tissue depends rather little on the source of the radiation (except that alpha is
somewhat more damaging than beta or gamma). As Table 2 on page 101
reveals, tritium emits beta radiation for which the energy in each decay is a
hundred times smaller than for caesium-137 and ten times smaller than for
carbon-14 [4]. So it takes a hundred times as much activity of tritium as
The human body is more than 50% water and roughly half of the rest is
carbon. The number of ordinary carbon atoms per kg in your body is
1,000(g in a kg)× 6×1023(atoms in 12g of carbon)× 0.25/ 12 = 1.6×1025.
Of these only 10-12 is carbon-14, so the number of carbon-14 is 1.6×1013.
On average they decay in 5,700× 3.1×107(sec per year)/ ln2 = 2.5×1011 sec.
So the number decaying per second per kg is 1.6×1013/2.5×1011
= 64 decays per second per kg. = 64 Bq per kg.
92 Chapter 5: Absorbed Radiation and Damage
caesium-137 (in Bq) to deliver the same radiation dose rate (in mGy per
month). Since it is difficult to discern the health effect of caesium-137 (as
will be shown in Chapter 6), it is even harder to discern the effect of tritium
on health.
Atomic analogues
In many ways a proton or neutron bouncing back and forth inside a nucleus
behaves in a similar way to an electron doing the same inside an atom, except
that the numbers are rather different. Many of the everyday changes that
happen around us – light and electronics, electrical and chemical changes,
and so on, concern the behaviour of electrons and atoms. So familiarity with
how atoms behave gives a window by which we can appreciate some of the
actions in which nuclei get involved, but with greater energy.
When the nucleus of an atom decays, it emits ionising radiation, either as a
charged particle or a photon. It is the difference in energy between the
nucleus before and after that provides the energy for the photon or the
particle. This is not an arcane process peculiar to nuclear physics; it is exactly
parallel to what happens in a chemical reaction or light emission by electrons
in the outer parts of atoms. Such emission of light is seen, for instance, in a
flame or a street light. So the yellow light emitted by each atom in a sodium
street lamp has a quantum energy – a photon energy – equal to the difference
in energy between two states in a sodium atom. Simple experiments in a
student laboratory show that atoms in the higher energy state decay to the
more stable state with a half life of about 10-8 seconds. In a normal discharge
lamp the electricity supply then provides enough energy to kick the atom
back up into its unstable state so that the process repeats and the lamp keeps
shining. In a filament lamp or flame it is the heat that re-supplies the energy
to the atoms that emit the light. The characteristic colour of a sodium or neon
advertising sign relates to the quantum energy; a mercury light involves
several unstable states that then give a mixture of photon energies that
appears whiter. In fact any material hot enough for its atoms to get kicked
into higher states will emit photons in this way, and this is why hot bodies
shine. The hotter they are, the more energetic the photons they emit, and the
more photons they emit, too. So, while the dull embers of a dying fire are a
pale red, the surface of the Sun, being much hotter, is much brighter and
includes yellow and blue too, making a brilliant white with all the colours of
the rainbow. The surface of some stars is even hotter still and they shine blue
or even violet.
These are examples of the radiation spectrum, whose peak colour rises with
temperature and whose overall brightness increases with the fourth power of
the temperature. This was first explained by Max Planck in 1900 when he
introduced the first revolutionary idea that grew in the 1920s into the
Nuclear is for Life. A Cultural Revolution 93
understanding of the physical world that today we call quantum mechanics or
quantum theory.
This is a suitable point at which to mention how energies are measured. In the
everyday world, energy is measured in joules (J), so that, for example, one
watt (W) is a power (or energy rate) of one joule per second.
The electromagnetic spectrum
The photons and particles, the radiation emitted in nuclear decay, are
indistinguishable in principle from those involved in the everyday physics of
electrons in the outer part of atoms. The only identity tags that they carry are
their energy and type. So the photons emitted in nuclear decay, sometimes
called gamma rays, are absolutely identical to those emitted by electrons that
have been accelerated from a heated cathode in an electron gun, such as used
to produce radiation in a dental clinic and usually called X-rays. In clinical
medicine, patients who express concern about radiation are occasionally told
that the radiation used in Computed Tomography (CT) scans or in modern
cancer therapy does not come from nuclei. This may indeed be true, but it is a
bogus argument because there is no distinction based on the source. The
descriptions X-ray and gamma ray are used more meaningfully to refer to
photons of lower and higher energy with a conventional change of name at
around about 100 keV, regardless of their origin.
Calling it quantum theory may give the wrong impression to a general
reader. In physical science the word theory does not describe some
speculative idea, as it often does in everyday speech, but a quantitative
understanding that may be used to make accurate mathematical
calculations for what occurs. The account of atoms and light given by
quantum theory has not changed since the late 1920s and its extension to
nuclei was clear by the late 1930s – and the details had been filled in by
the 1950s. There is nothing speculative about today's understanding of
nuclear physics – and that includes the numerical value of quantities.
However, these units are inconveniently large to describe the behaviour of
a single atom or nucleus. Atomic energies (for each atom) are measured
in electron-volts (eV), where 1 eV is the energy gained by an electron
accelerated by 1 volt. Then 1 eV = 1.6×10-19 joules because that is the
electric charge of an electron. So that a 60,000 volt gun in an X-ray tube
produces electrons of 60,000 eV. Nuclear energies, being typically a
million times greater than atomic energies, are measure in MeV, where 1
MeV = 1.6×10-13 joules. This is still tiny on our every-day scale, but
enormous at the scale of a single atom.
94 Chapter 5: Absorbed Radiation and Damage
The spectrum of photons extends from gamma rays of the highest quantum
energy and highest frequency (and wavelength much smaller than nuclear
size) down to very low-frequency radio waves (and wavelength exceeding a
km). This is shown schematically in Illustration 22. In the centre is the
spectrum of light with its explicit rainbow in a narrow band. At wavelengths
a bit longer (to the right) there is the infrared range; here, radiation is
absorbed readily because it matches the natural rotation and vibration
frequencies of molecules. At wavelengths just shorter than visible light is the
ultraviolet range where materials absorb radiation strongly at the frequencies
with which electrons vibrate in atoms. In between is the optical region, the
light we can see; this is the fortunate range for which the energy emitted from
the Sun's surface is maximum and also where many materials are transparent.
It is no coincidence that this is the only range for which our eyes have
evolved some sensitivity.
In the infrared to radio ranges, one photon by itself does not have enough
energy to ionise a molecule, and in this range radiation is called non-ionising.
Such radiation can only cause damage to atoms and molecules by heating
them as a whole through the cumulative absorption of very many photons.
However, if the total absorbed energy is high enough – as in a microwave
oven – the material will start to get hot and then cook, if it is biological.
Similarly, radiation from a mobile phone will warms tissue a little – not
much, however, because most of the radiation passes straight through. Non-
ionising radiation is harmless because the painful sensation of heat tells you
to move out of the hottest sunshine, or take your feet away from the fire. If
you cannot feel the heat it creates, it is quite safe. Public worry about the
safety of non-ionising radiation only began recently when someone noticed
Illustration 22: A schematic diagram of the regions of the radiation
spectrum, shown with the wavelength increasing to the right (and so
lower quantum energy) and the frequency increasing to the left (and
so higher quantum energy).
Nuclear is for Life. A Cultural Revolution 95
the word radiation!
Linearity and its applicability
Initial radiation damage
In the ionising region of the photon spectrum, that is on the left in Illustration
22, two significant changes are evident. Firstly, to the left of the UV
absorption region, materials become increasingly transparent, meaning that
radiation can penetrate deep into living tissue before being absorbed, and
even pass right through and out the other side. This is the essential advantage
that X-rays and gamma rays can offer to medicine, and that allows imaging
and cancer therapy within the body without invasive surgery and its traumatic
effects. The second difference is another consequence of quantum mechanics,
noted by Einstein in his work on the photoelectric effect in 1905. The energy
of the radiation when it is absorbed is not smoothly spread through the
material, but is delivered as a series of distinct events (often called
collisions), each such event being the absorption of a single photon. The
initial damage at the site of an event depends on the energy of the single
absorbed photon and whether it can ionise or break a molecule, not on the
brightness of the total radiation flux. As a result, ionising radiation, including
UV, can damage materials at lower energy fluxes than non-ionising radiation,
and it does so without raising the temperature. This piecemeal action means
that the effect of each photon is separate. The total damage to the material is
proportional to the number of photons and quite independent of whether the
photons all arrive at once as an acute dose or are spread out in time over an
extended period of hours, months or even years. The total damage is also the
same if the same radiation is spread out in space over a whole body or
concentrated into a small spot: also, if spread over many people or all
concentrated on one person.
This implies that the effect of radiation is linear because each photon acts
independently. So the combined effect of a thousand photons is a thousand
times the effect of just one. This is precisely the condition for linearity
discussed in Chapter 4. It means that the immediate damage caused by
radiation is linearly related to the total absorbed radiation energy, and there is
no intensity of radiation so low that there is no such damage. And this
conclusion is true for all materials, whether alive or dead.
LNT model of long-term damage
The assumption that this simple picture applies even to the resulting long-
term radiation damage to living tissue is called the Linear No-Threshold
(LNT) model. Looking at this model, why it is wrong and the evidence that
confirms it is wrong, is a major objective of this book. Here is a brief
96 Chapter 5: Absorbed Radiation and Damage
summary of the justification for the LNT model:
The energy of radiation is deposited in an irradiated material as a
series of essentially separate collisions. Therefore the net damage
done to the structure of the material can be assessed by just adding
up the energy of those separate collisions. Further, since there is no
minimum total energy flux for a collision to occur, there is no
threshold for damage and any radiation flux, however weak, incurs
damage. (The contrary would be the case if, for example, damage
only began when the temperature of the material was raised to some
threshold.) In the cells of living tissue the significant damage is
genetic damage to the structure of DNA. Such radiation-induced
damage may be passed down to successive generations when the
DNA is copied.
If this description were complete, a significant implication for society would
then follow:
Nobody should countenance leaving such a genetic legacy. Therefore
all ionising radiation exposure should be reduced to a level As Low
As Reasonably Achievable (ALARA) and the use of any technology
using ionising radiation, including nuclear energy, should be avoided
wherever possible.
It might be asked:
How could such a picture based on the simple concept that was
confirmed by Einstein with his Nobel Prize winning explanation of
the photoelectric effect, actually be wrong?
Nevertheless, we shall show evidence that it is wrong, and pinpoint how this
mistake occurred. This historical tale is recounted in Chapter 10.
Failure of LNT model for live tissue
The basic error is in thinking that any initial damage persists in the longer
term, as indeed it would in dead or passive material – in other words, material
not actively maintained by biological mechanisms. The LNT model ignores
how biological life reacts to damage following a radiation dose. In this
discussion we need to understand the effect of this biological reaction, how it
works in principle, why it evolved and the evidence that confirms that its
effectiveness is not the exception but the rule.
To make sense of the evidence, we shall need to quantify the energy of
radiation doses, so that we can compare them for different practical
situations. In traditional descriptions of radiation doses and their safety, the
LNT model is already taken for granted. Since the evidence will show
unequivocally that the LNT model is mistaken in its picture of biological
radiation damage, we must take great care not to follow the LNT description
Nuclear is for Life. A Cultural Revolution 97
of radiation damage. This means that the next section matches only part of
what is to be found in traditional radiation safety handbooks.
Quantifying absorbed radiation
Radiation doses and radiation dose rates
Radiation that passes straight through the body is harmless. It is only the
energy that is stopped and absorbed that can do any damage, and that is what
we need to discuss. Quantitative measurements allow comparison of doses in
different situations. They enable meaning to be given to the scale of doses
otherwise described simply as high or very high. Such comparisons bring
some interesting surprises, for instance, the rate of energy in an ionising
radiation exposure and the power from a simple light bulb, or between
environmental and medical doses of radiation.
For the high doses used in cancer therapy, the precise dose delivered to the
patient is important and mistakes of a few percent in the delivery can have
consequences for the success of the treatment or even the survival of the
patient. However, at lower doses the need is to note and understand the
factors of ten involved – factors of two or three are not usually of practical
importance for safety [5].
Energy is a well-defined quantity like mass, distance and time. An electricity
meter charges you for measured energy in joules (J), with 1 Unit = 3.6
million J, so a joule is small in everyday terms. Actually the utility meter
measures power, that is energy rate, in joules per second and then
accumulates the total joules over time. One joule per second is called a watt
(W, named after James Watt, the eighteenth century Scottish inventor).
Radiation dose is a measure of the energy absorbed in each kg of tissue – so
we have dose in joules per kg, and dose rate in watts per kg. A dose of one
joule per kg is called a gray (Gy, named after Louis Harold Gray). Medical
doses are often quoted in cGy (1 cGy = 1/100 Gy = 1 rad, an older unit);
environmental doses are conveniently given in mGy (1/1000 Gy). These
definitions and measurements are unaffected by whether LNT is assumed and
that is why we use them here.
For radiation safety what is really of interest is how much harm the absorbed
energy causes to living tissue. Can we use the absorbed energy as a surrogate
for the biological damage? It will do if we assume that they are directly
linked, won't it? As the evidence will show, it will not.
We may think of the scoring in a tennis championship as a parallel. Over the
years, to identify the champion beyond reasonable doubt, a scoring scheme
has evolved that works very effectively, more so than in many other sports,
98 Chapter 5: Absorbed Radiation and Damage
perhaps. The result is exciting and competitive, but, notably, during a match
all of the smaller points within a game are discarded. An LNT-like view of
tennis might advocate selecting the champion by simply adding up all the
points played and treating that as a surrogate for each player's ability. If that
made for the most effective type of tournament, no doubt that would have
been chosen years ago. But that did not happen, probably because it would
miss the rise and fall of psychological tension that goes with the more
structured scoring scheme. The evidence provides the answer, not an appeal
to theoretical simplicity.
In the case of radiation, what kind of harm matters? Much of the damage to
the contents of cells in irradiated tissue is of no lasting consequence, as most
molecules are replaced regularly as part of the cell cycle. But damage to the
DNA is different because it controls the copying process itself – it is the
master record for the cell, coordinates its function and itself gets copied in the
cell cycle, thereby potentially propagating damage to subsequent cell copies,
even creating a flaw that could be passed to subsequent generations.
However, this is a theoretical possibility that is only important if it happens –
it is a matter for evidence to tell whether damage is actually propagated in
this way.
The main question is how the biological damage is related to the energy
absorbed. The LNT assumption is that damage is directly proportional to the
dose. In the LNT model, after making some modest but poorly defined
adjustments for the rate, tissue and type of radiation, the energy dose itself is
taken as a surrogate for damage, but given the fresh name of sievert (Sv)
instead of gray (Gy). But as will become evident in succeeding chapters, this
is not a measure of the damage that we should expect for an active material
like living tissue on the basis of modern biology. Nor does it match what is
observed in the natural environment, a patient clinic, an animal laboratory
experiment, or the casualties from an accident with radioactivity.
In the LNT model biological damage in sievert (or millisievert, mSv) is not
measured but the result of applying assumptions. Without these the sievert is
not meaningful. Within LNT the linear relation between Sv and Gy is
assumed to be a simple numerical equality for beta, gamma and high-energy
X-rays. Of radiation types frequently found in the environment only alpha is
much different; it is assumed to deliver 20 times as much damage – that is
each Gy of absorbed energy (per kg) gives 20 Sv of damage (per kg).
Neutron and proton radiation have been assigned similar weighting factors
too, but neither of these is often found outside a research laboratory or the
core of a working reactor, so we ignore them here for simplicity.
Nuclear is for Life. A Cultural Revolution 99
The evidence will show that what reflects the biological damage more than
the total absorbed energy is the rate at which energy is locally absorbed, that
is the dose rate. This may be measured in mGy per month, for example.
Obviously, reckoned in mGy per year the number would be 12 times larger,
and in mGy per second, correspondingly much smaller. However, the use of
an arbitrary period makes no sense. The important choice of time period is
one to be made with data.
So what is the reason to choose a repair time of a month? This interval was
discussed in Radiation and Reason, Chapter 7 [see Selected References on
page 283, SR3]. Essentially it is the biological recovery time and so covers a
range of values roughly spanning the typical cell cycle time and leading to a
month as a conservative choice for safety purposes.
Measurement of radioactivity in becquerel
The dose rate that comes from a radioactive source depends on the activity of
that source, and with some assumptions we can relate these two.
Radioactivity is measured in becquerel – 1 Bq is one radioactive decay per
second. This is a very low rate indeed, and the energy released by each decay
is minute. Significant rates may be measured in thousands (kBq), millions
(MBq) or even millions of millions (TBq) of decays per second. A technical
point is that Bq refers to the total decay rate – to get the rate per kg the
number of Bq needs to be divided by the weight in kg. But notice that Bq is
already a decay rate per second, so it does not need to be divided by the
exposure time. The energy dose in mGy is the other way around – it is
defined as the dose per kg, but to get a dose rate it must still be divided by
the dose delivery or exposure time. So an annual dose, reckoned in J per kg
Considerations that might complicate the simple relation between energy
absorbed and final biological damage are ignored in the LNT model. In
particular the possibility that patterns of deposited energy overlapping in
space or time might influence the final outcome are excluded – incorrectly
as evidence shows. In the LNT model a dose spread out chronically over
the life of an individual is reckoned to be as damaging as a single acute
dose of the same integrated energy received in days or hours within a
small factor of about two. (In LNT this factor is called DDREF. If LNT
does not apply, DDREF has no meaning.)
By a simple extension of linearity, the LNT model would imply a dose
dispersed among many individuals is as damaging as the same total dose
given to one individual. This would be administratively convenient, if
true, because the total damage could be assessed simply from the dose
added up for a population, an estimate called the collective dose.
100 Chapter 5: Absorbed Radiation and Damage
(or Gy) received over a whole year, has to be divided by 31 million – the
number of seconds in a year – to get the dose rate in Gy per second, the same
as watts per kg. It is a matter for the evidence, not pre-conceptions, to decide
whether it is the dose or the dose rate that is more significant, and it certainly
makes a lot of difference: a difference that is frequently glossed over.
Finding a dose rate from a measurement of
radioactivity
Sometimes the radiation dose received is caused by radioactivity within the
body. In that case it is relatively simple to calculate the dose from the
radioactivity, or vice versa, by assuming that all of the radiation emitted in
the decay is absorbed. With this assumption the dose may be overestimated
somewhat. For alpha all of the radiation is absorbed, but for beta about half
the released energy escapes as invisible neutrino radiation, and for gamma a
fair fraction may escape the body too.
When it decays, a nucleus releases a small amount of energy, call it E. In
principle, to get the dose from the decay rate, we add up the energy of all
these decays. The number of decays is the rate in Bq multiplied by the
number of seconds for which the dose is accumulated. To find the dose, we
multiply this number of decays by E and divide by the weight in kg.
The energy E of each radioactive decay, expressed in joules, is a very small
number, even for a nuclear decay. Nuclei differ but most of the energies fall
within a modest range. Table 2 shows the energy for some of the more
important decay energies: these are clustered around 1 MeV = 1.6×10-13 J.
(This number is simply a million times the electric charge of an electron.) So,
assuming that all the energy is absorbed, the conversion from radioactivity
(Bq) to dose rate (mGy/month) goes like this:
As examples, we apply this calculation to the natural radioactivity in any
human body, and then to the ingestion of contaminated water and food at
Fukushima. Such calculations are not exact but they give answers, often
correct to a factor two to four, and sufficient to show what is safe.
dose rate (mGy/month) = radioactivity(Bq) × E(MeV) × 1.6×10-13 (J/MeV)
× 2.6×106 (secs/month) × 103 (mGy/Gy) / 70 (mass of an adult in kg).
Nuclear is for Life. A Cultural Revolution 101
Decay Energy, MeV Main decay type Radioactive half life,
sec
Tritium, H-3 0.018 beta 3.9×108 or 12 yrs
Carbon-14 0.16 beta 1.8×1011 or 58,000 yrs
Potassium-40 1.32 beta, gamma 4.1×1016 or 1.3×109 yrs
Cobalt-60 1.17 + 1.33 beta, gamma 1.6×108 or 5.3 yrs
Strontium-90 0.54 + 2.28 beta 8.8×108 or 28 yrs
Iodine-131 0.97 beta 6.9×105 or 8 days
Caesium-134 2.0 beta, gamma 6.6×107 or 2.0 yrs
Caesium-137 1.18 beta 9.5×108 or 30 yrs
Polonium-210 5.3 alpha 1.2×107 or 0.39 yrs
Radon-222 5.5 + 6.0 + 7.7 alpha 3.3×105 or 0.01 yrs
Radium-226 4.8 alpha 5×1010 or 1600 yrs
Thorium-232 4.0 alpha 4.5×1017 or 1.4×1010 yrs
Uranium-238 4.27 alpha 1.4×1017 or 4.5×109 yrs
Plutonium-239 5.24 alpha 7.7×1011 or 25,000 yrs
Table 2: Some frequently discussed radioactive isotopes. Where several
energies are given, these are sequential decays to be added.
In most cases of contamination, radioactivity gets distributed throughout the
body and the radiation energy is then further spread out by the smudging
effect of its range – the dose is not absorbed where the radioactivity was. This
spreading is true for the important cases of potassium-40, caesium-137,
tritium and carbon-14. Some radioactive elements accumulate in bone –
strontium-90, radium-226, plutonium-239 and other metals – but that still
gives rise to a widely spread distribution of absorbed energy. Radon is a gas
and its radioactive decay products get caught in lung tissue. Iodine too is a
special case because it is concentrated only by the thyroid gland and then
decays with a half life of only a week, resulting in a concentrated acute dose.
As evidence will show later, it is the dose rate that matters to health, much
more than the accumulated dose. The length of time for which the flow of
radiation persists depends both on the half life of the radioactivity and on the
rate at which the radioactivity is expelled from the body, sometimes called
the biological half life [6]. If the biological half life is shorter, it will be more
important than the radioactive half life given in Table 2. Such depletion is
102 Chapter 5: Absorbed Radiation and Damage
important for both caesium isotopes shown in Table 2, which have a
biological half life of about 100 days, but somewhat less for children who are
thus at less risk than adults. This depletion does not apply to potassium-40
because it occurs naturally in the body and persists indefinitely.
If the radioactive source is outside the body altogether, the fraction absorbed
is very much lower. Then, most radiation does not enter the body at all and
exposure is easily reduced by simply moving away or reducing the time for
which radiation is absorbed. Unless the source is very close, the radiation
dose to the body falls with the inverse square of the distance. So, for instance,
by moving three times further away from the source, the radiation dose is
reduced by a factor of nine.
Natural internal dose
The natural internal radioactivity in the body is about 7,400 Bq. This is
mostly due to potassium-40 and carbon-14, as used in radiocarbon dating.
However, as shown in Table 2, the latter contributes a very small decay
energy of less than 0.2 MeV, so that potassium-40 dominates the dose.
We calculate the annual dose that the natural activity of 4,300 Bq potassium-
40 gives to a 70 kg man:
Illustration 23: A diagram of the average annual radiation dose to
the UK population, total 1.4 mGy per year. Based on data for 2005.
4,300(Bq) × 3.1×107(sec/year) × 1.32(MeV energy per decay)
× 1.6×10-13(J/MeV) × 1,000(mGy/Gy) / 70(kg per adult) = 0.4 mGy/yr.
Nuclear is for Life. A Cultural Revolution 103
This is an over-estimate because not all the beta-decay energy is absorbed
(the neutrino escapes altogether). A better calculation would give an answer
just less than 0.3 mGy/yr. This dose rate from internal activity is the same for
everybody everywhere, and Illustration 23 shows that it accounts for about
18% of the average background dose rate of 1.4 mGy per year.
Note: the numbers in Illustration 23 look a little different from those
normally quoted. That is because they are shown in mGy, instead of mSv.
In mSv according to the LNT model, the contribution from radon is
weighted by a factor of 20 as an alpha emitter. This factor has been
removed, and so radon no longer dominates the average background and
the quoted doses in mGy.
Other sources of natural background radiation
Other contributions to this average background shown in Illustration 17 are
more variable. For example, the cosmic flux is partially shielded nearer to the
equator by the Earth's magnetic field, but increases by about three times at
the Earth's magnetic poles. It also rises with height by a factor of ten at
35,000 feet. This is caused by the primary cosmic flux from space generating
secondary radiation showers at the top of the atmosphere that are absorbed by
the denser atmosphere at lower altitudes.
Today a significant contribution to the average annual dose comes from
medical procedures. Such doses have been rising yearly as more effective use
is made of radiation for diagnostic imaging. This dose is a very long way
indeed from being a genuine cause for concern – some two or three whole-
body scans per week, every week, for 4 or 5 years would be needed before
any negative health effect might become evident. But we return to this
question in Chapters 8 and 9 because it is seen to be a source of popular
concern.
Illustration 23 shows that a major contribution to the annual background
radiation dose comes from gamma radiation and the ingestion of radon, both
of which emanate from rock, water and soil, and are therefore dependent on
the local geology which is very variable. Interestingly, some of the lowest
annual doses are experienced by the crews of nuclear submarines, who are
particularly well shielded by the ocean water from cosmic radiation and
emissions from geological rocks. Some of the highest are experienced on
high-altitude trans-polar flights, such as those taken by many who fled from
Japan for Europe and the USA in March 2011. Indeed, on one occasion in
2013 on my way to Japan I omitted to turn off my own radiation monitor and
it bleeped an alarm above 25,000 feet, albeit at an irrelevantly low radiation
level. For some moments I thought my phone was ringing! Thankfully,
nobody on the plane took any notice anyway.
104 Chapter 5: Absorbed Radiation and Damage
Food regulations at Fukushima and Chernobyl
On 29 July 2011 the Japanese government published regulations that set the
level of radioactive caesium in meat, above which it should be treated as
contaminated, at 500 Bq per kg [7]. In April 2012 and April 2013, as a result
of public concern, the level was tightened further to 100 Bq per kg [8]. What
dose would someone receive if they regularly ate meat contaminated at this
level?
The first government announcement stated that eating 1 kg of meat
contaminated at 500 Bq per kg would give a dose to the whole body of 0.008
mSv, or more correctly 0.008 mGy. However we do not need to believe this –
we can try a calculation ourselves.
Both caesium isotopes, caesium-137 and caesium-134, have a biological
lifetime in the body of 100 days and we treat them together. Caesium has a
chemistry like potassium and if ingested or inhaled, it becomes spread rather
uniformly through the body like potassium. The period is 9 million seconds
(100 days), so the dose over 100 days from eating 1 kg of meat (at 500 Bq
per kilo) would be about:
500(Bq) × 9×106 (seconds) × 1.18(MeV) × 1.6×10-13(J/Mev)
× 1000 (mGy/Gy) / 70(kg adult weight) = 0.012 mGy per kg eaten.
This calculation has ignored that some gamma radiation and neutrino energy
escapes from the body, and so is expected to be an over estimate. It is quite
consistent with the figure of 0.008mGy per kg given in the regulation [7].
Now we can ask a question, and then calculate the answer:
How much contaminated beef would a person need to eat in three
months (100 days) to receive a dose equivalent to one medical
diagnostic whole-body radiation scan, that is about 8 mGy?
The answer has to be 8 mGy divided by 0.008 mGy per kg, that is
1,000 kg = 1 tonne.
Obviously no one could eat so much meat in that time, and so ever receive
such a dose under any circumstances. Consequently the regulation is
ridiculous. Added to which, one such scan in three months is quite harmless –
the threshold for any damage to health is at least 30 such scans in that time
(on the basis of case made and evidence given in Chapter 9). Hence the
Regulation of July 2011 has no rational basis, while those of April 2012 and
April 2013 are even more illogical, as they relate to a personal consumption
of five tonnes in three months!
After the Chernobyl accident there were similar concerns about levels of
radioactive contamination of meat in Scandinavia. In June 1986 in Norway
Nuclear is for Life. A Cultural Revolution 105
the maximum activity permitted for food stuffs was set at 600 Bq per kg. The
economic effect on the reindeer industry was so severe that in November
1986 this was relaxed to 6,000 Bq per kg [9]. In Sweden, 16 years later, on
the 24 April 2002, the Swedish Radiation Protection Authority published an
apology in the daily press [10]. They admitted that the intervention level had
been set too low and that 78% of all reindeer meat had been destroyed
unnecessarily, at great expense to the taxpayer and adversity to the industry.
They lamented what had gone wrong, but still seemed unaware that the fault
lay with the paternalistic application of ALARA-based principles to the
safety of nuclear radiation. They were surprised that at the failure of their
policy of setting a tight limit and telling the public that they should not worry.
They did not understand that human nature is not set up to accept such a
passive role.
Water release at Fukushima
The natural internal radioactivity of the body is 100 Bq per litre, that is close
to the limits set for drinking water in Japan as reported in Sept 2011 [11]. This
shows that the regulation is not related to any risk – it is said to be
precautionary and describes a level of radioactivity that exists in nature
anyway. It is intended to reassure and pacify public opinion – it does not
depend on science. Worse, this appeasement is not effective and once trust is
lost, the public remain disturbed, whatever limit is set.
On 4 April 2011 the Tokyo Electric Power Company (TEPCO), the company
operating the Fukushima Daiichi plant, announced that it was releasing
11,500 tonnes of radioactive water into the sea [12]. It was forced to do this
because it had built up an excess of contaminated cooling water, and it
needed more storage capacity for water with greater contamination. It also
said that the activity was about 100 times the regulation safety limit at 100
Bq per litre (at that time), but that it was quite safe. The apparent
contradiction between these two statements stretched TEPCO's credibility in
the eyes of the public and the press.
A calculation is illuminating. The total activity to be released was 1.5×1011
Bq, that is 13,000 Bq per litre, or 130 times the regulation limit for drinking
water. We can calculate what dose would be received by someone who drank
a litre of this water every day for three months. (To make a comparison we
assume that the activity was mainly due to caesium since some weeks after
the accident any contribution from iodine-131 with its 8-day half life was
already much smaller and continuing to fall.) The total imbibed activity
would therefore be 1.3 million Bq, and the dose would be
1.3×106(Bq) × 9×106(secs) × 1.18(MeV) × 1.6×10-13(J/MeV) ×
1,000(mGy/Gy) / 70(kg adult weight) = 32 mGy spread over 3 months.
106 Chapter 5: Absorbed Radiation and Damage
Even though nobody should be encouraged to drink this water, day after day,
the radiation dose received by anyone who did so would be similar to that
from one whole-body CT scan per month. We conclude that both statements
made by TEPCO are true. What is false is the understanding that 100 Bq per
litre is the limit of safety. Public policies may be factually correct, but, by
quoting precautionary levels unrelated to any evidence of risk, such as 10 Bq
per litre, they simply encourage a race to the bottom and a demand to ban any
additional radiation at all [13]. To reassure the public, recent announcements
about discharges to the ocean refer to activities that are a small fraction of
drinking water guidelines [14]. Adherence to such standards costs money, but
to what purpose?
Good safety is a matter of distinguishing clearly those situations that are safe,
from those that are dangerous and should be given a wide berth. Saying that
all discharges of radioactive water into the sea are hazardous is itself a
dangerous statement. Consider a parallel in road safety: advising children to
keep away from the edge of the roadway unless crossing should not be
confused with warning them of the fatal consequences of remaining in the
fast lane. Neither risk is a reason to close all highways, assuming that an
elementary level of education is given. An equivalent simple provision for
radiation is not given in any country.
On 2 April 2011 an unintended leak of a much smaller mass of water, 520
tonnes, was discovered with an activity of 4.7×1015 Bq and this was reported
as successfully sealed off by 6 April. This was more dangerous, but the
volume was small and became diluted to negligible levels in the ocean.
Nobody was affected and there was no casualty unlike in other major
accidents, such as the fire on the Piper Alpha oil rig in 1988 where 167
personnel were caught in the wrong place and died.
Dose rates from external radioactive contamination
The dose received is quite different if the radioactivity is external to the body.
It is important to know the dose rate experienced by someone at a place
where there is a nearby source of radioactivity. For instance, if the
radioactivity on the ground was one million Bq of caesium in each square
metre, how many mGy per month would someone receive who stood there?
This question is too vague to give a clear answer, but we should try. Where
does the radiation get absorbed? Half of the radiation emitted will go
downwards and be absorbed in the ground. Some of that emitted upwards
would be absorbed before it reaches anybody, too. It depends on whether the
radioactivity is on top of the ground or lies below the surface – and that may
not be known. If it is alpha radiation, it will all be absorbed in a few
centimetres of air, so external sources of alpha activity are not a concern
unless ingested in some way or absorbed through the skin.
Nuclear is for Life. A Cultural Revolution 107
For beta or gamma we can calculate the most pessimistic case in which all
the radiation going upwards is absorbed by a human body with horizontal
area, half a square metre. The dose that we calculate in this way will be an
over-estimate, perhaps by as much as a factor of ten. If we knew more about
the kind of activity and where it lay, below or on the ground, we could lower
the estimated dose. Here is the calculation for the monthly dose, assuming
that the recipient is exposed continuously 24/7 and without clothes –
exceptionally pessimistic assumptions.
This is equivalent to having two whole-body CT scans in a year and is a
factor of 50 below the level of 100 mGy per month – the dose rate that is a
scientifically justifiable safety threshold [see Chapters 1 and 9]. Any actual
dose received by an individual is reduced further, unless the person lives on
the spot with a million Bq per square metre. Wearing clothes or moving
around will tend to reduce an external dose – unlike an internal source of
radiation that remains present continuously until it decays, is excreted or
exhaled. The highest-dose zones, shown in red on the maps of Fukushima,
Illustration 13 on page 44, indicate where the dose rate is greater than 166
mGy per year (14 mGy per month) at a height of 1 metre. That is on the safe
side of the limit suggested in Chapter 9 by a factor of approximately five.
But this is missing a rather important practical point. It is very difficult to
measure the concentration of radioactivity on the ground. Radioactive atoms
only differ from non-radioactive ones of the same chemical element by their
decay and their mass. So the simplest practicable way to detect small
quantities of radioisotopes is to measure the radiation that they emit. But the
fraction of emitted radiation that reaches a detector will depend on whether
the radioactivity is just on the surface, or buried a few millimetres below the
surface; the latter will often be the case for open ground. Detection will also
depend on the energy and type of radiation. Alpha radiation is absorbed by a
few cm of air; beta radiation is not easily identified and can be much
attenuated before it reaches the sensitive volume of a detector; only gamma
radiation is detected and its source identified reasonably easily and
efficiently. Although measurements are hard to make, exposure to external
radiation is easily reduced by limiting exposure time, keeping at a distance
from the source and using absorbing materials.
Just as a smoke alarm does not need to be precise to provide reassurance
about fire, a radiation alarm can be quite crude and yet provide reliable
safety. Simple devices that indicate a dose rate in mGy per hour usually count
ionisation pulses in a crystal or gas and assume that these are due to gamma
106 (Bq per m2) × 3×106 (secs per month) × 0.25 (0.5 m2, ½ up)
× 1.18 (E MeV, for caesium) × 1.6×10-13 (J per MeV) × 1,000 (mGy per
Gy) / 70 (kg) = 2.0 mGy per month.
108 Chapter 5: Absorbed Radiation and Damage
rays of about 1 MeV. To do better, the energy of each pulse should be
measured using a crystal like sodium iodide which can trap and measure the
energy. Ultimately the radioisotope concerned would have to be separately
identified, and the shielding effect of surrounding materials accounted for.
But generally, for rough measurements in the environment with a hand-held
instrument, this sort of detail is not available.
Comparison of ionising and non-ionising radiation
In the media, radiation fluxes are frequently described as high or very high,
without any scale. Only if numbers are given, can any meaning be given to
such descriptions. Below are a few examples of non-ionising and ionising
radiation energy fluxes – the numbers are not precise, but sufficient to
illustrate some differences, since these are large.
1. The energy consumption of the human body at rest, or the metabolic
rate, is about 1-2 watt per kg, but this rises to about 6-10 watt per kg
with mental or physical activity. Perspiration and convection in the
human body are familiar ways in which the extra heat load is
dispersed.
2. The safety limit for non-ionising radiation absorbed in live tissue is 4
watt per kg (set by US FDA). This limits the maximum
radiofrequency power that is allowed for an MRI scanner or a mobile
phone. If the power were higher, live tissue would start to feel hot.
3. A domestic microwave oven delivers about 800 watts, so the food
absorbs about 800 watts per kg that heats and cooks it. This is 100
times the metabolic rate, so taking exercise or thinking hard does not
release enough heat to cause self-cooking. This is indeed reassuring!
4. Sunshine has an energy flux above the metabolic rate which is why
we feel significantly hotter in the sunshine. The solar constant, the
flux of radiation reaching the Earth from the Sun, is 1,300 watts per
square metre in total. Depending on conditions the flux of ultraviolet
(UV) might be 30 watts per square metre, or about 0.1 watts per kg,
averaged over a human body [15].
5. Natural internal radioactivity in the body gives a dose rate 0.3 mGy
per year, that is 9×10-12 watt per kg. The big reduction factor comes
from the 31 million seconds in a year. The average total background
ionising radiation is between 5 and 100 times larger, depending on
location.
6. The absorbed energy dose rate from a PET scan (or from a CT scan
notionally spread over an hour) is about 10 mGy per hour – this is
0.01 joules per kg per hour – and an absorbed energy rate of 3×10-6
Nuclear is for Life. A Cultural Revolution 109
watts per kg.
7. During a course of high-dose therapy the local healthy tissue receives
an absorbed dose of 1,000 mGy, each day for 4-6 weeks – notionally
spreading each daily treatment over an hour, that is 3×10-4 watts per
kg.
Metabolic
rate
Sunshine Natural
internal
radiation
Average UK
ionising radiation
background
CT or
PET
scan
radio
therapy
total UV
1 ~ 10 ~ 1/10 10-11 5×10-11 3×10-6 3×10-4
Table 3: Some approximate energy rates relative to the resting
metabolic rate.
In Table 3 these absorbed energy fluxes are compared. Although the numbers
are rough, the energy fluxes of sunshine and the metabolic rate are four
orders of magnitude (factor of 10,000) greater than that of radiotherapy and,
in turn, that is two orders of magnitude (factor of 100) above a diagnostic
radiation scan; that in turn is another four or more orders of magnitude
(factor of 10,000) above the average background ionisation energy flux,
effectively the baseline for ALARA safety.
Expressed in another way based on the definition of a Gy, exposure to full
sunlight gives a total energy flux of about 1,000,000 mGy per second. This
indicates just how truly minute is a radiation flux that delivers 1,000 mGy per
year.
So any description of a radiation flux as high should be seen in perspective;
fluxes of ionising radiation are actually tiny. What happens is not a general
macroscopic story, but a microscopic one, concerned only with the tiny
fraction of atoms or molecules that get a hit – the rest are not affected in any
way. We can find the approximate number of those that are affected quite
easily. There are about 5×1025 atoms in a kg and to ionise one of them takes a
few eV, that is about 5×10-19 joules. Then a CT scan of 10 mGy will ionise
about 2×1016 atoms per kg, that is about 2 out of 5,000 million atoms. That is
indeed very few, about the same as two small grains in a whole 5-tonne truck
load of sand. It does not imply that the damage may not be significant – an
examination of medical data will show whether this tiny minority of damaged
atoms or molecules is a threat to a living organism or not. Nevertheless, we
see that the vast majority of molecules are not influenced at all by a typical
flux of ionising radiation. What determines which atoms are affected? That is
chance. It is the essential randomness of quantum mechanics at work!
It is hardly a surprise that it is not possible to feel ionising radiation from a
CT scan or even radiotherapy, because the energy rate is only microwatts.
110 Chapter 5: Absorbed Radiation and Damage
The molecules unlucky enough to get hit can feel it – but that is only 1 or 2 in
5,000 million. When the authorities announce to the press that very high
radiation levels have been measured as a result of an accident, perhaps they
should find out more precisely what that means and explain it to the people
before allowing alarm and economic disruption to spread.
Safety and sunshine
We may ask what happens to this tiny minority of damaged molecules. The
response to UV in sunshine is not a good example in some respects, but it is
familiar and has some interesting things to say. Compared to X-rays or
gamma rays, UV is exceptionally inefficient at ionising, but this is off-set by
the extremely high flux of photons. Probably the majority of people are
familiar with sunbathing and its effects; these are similar to those of nuclear
radiation and in practice more serious. As most children learn from their
parents, there are two kinds of damage:
- cell death, when layers of skin peel off that we know as sunburn and from
which there is usually good recovery in a few days;
- skin cancer that may appear many years later and is often fatal, if not
treated.
Compared to beta and gamma radiation, UV does not penetrate far through
the skin, but is no less dangerous for that. There are 9,000 deaths from skin
cancer each year in the United States [16]. This is a rate of 30 per million, that
may be compared with the death rate of 10 per million from fire [17] and 103
per million from highway accidents [18]. In all three cases public attitudes are
reasonably informed, but could be improved. The authorities work to extend
awareness, but at least there is no worldwide panic and no social or economic
upheaval. In the recent past, however, in the case of nuclear radiation, the
authorities have done nothing to inform the public, allowing apprehension to
increase. Although the number of deaths from nuclear radiation is 10,000
times smaller than that from UV radiation, the population is not instructed
and hangs on every word of ill-advised panic advice readily offered by the
media. The result is highly destructive of trust in science and of mutual
confidence in society as a whole.
In fact the immediate effects of high doses of radiation appear as skin burns,
just as for excess UV. Such burns can be a side effect of a radiotherapy
course and can be treated relatively quickly. Those people caught in some of
the accidents to be described in Chapter 6, who received excessive radiation,
also recovered. They include the crew aboard the Lucky Dragon fishing boat
[Chapter 10], the 28 hospitalised patients at Goiania who underwent surgery
[Chapter 6], and the two workers who got their feet wet in the Fukushima
basement [Chapter 3].
Nuclear is for Life. A Cultural Revolution 111
The public view of the dangers of UV – in spite of the very real risks – is
refreshingly different from that of nuclear radiation. People have learnt
something about barrier creams and they know that the Vitamin D produced
by sunshine prevents rickets. They have been warned of the danger of skin
cancer caused by repeated over-exposure. Most are sensible and enjoy their
summer vacations in the sun, gently engaging in natural acclimatisation in the
first few days. This is the very kind of time-adaptive process that is important
in the reaction of tissue to nuclear radiation, and crucial to the scheduling of
radiotherapy treatment, but explicitly ignored by the current ALARA
radiation safety regime.
Illustration 4 on page 5 shows an example of effective safety information: a
plastic carrier bag given away by a local pharmacy which offers sensible
advice to parents and their children on living with ultraviolet radiation. In
spite of the high death rate from skin cancer, society is content to take normal
medical advice and learn what to do – rather than rushing to consult a
committee of the United Nations. If popular attitudes to UV radiation were to
match those to nuclear radiation, travel firms might have a good trade in
selling summer vacations deep underground with tours restricted to moonless
nights to avoid the horrors of skin cancer. People have learned that the risks
and benefits of UV should be balanced, and they should learn to do the same
for other forms of radiation too. History is the only reason to single out
nuclear radiation for special concern, but the historical story is flawed, as
explained in Chapter 10.
What happens to radiation in materials
Range and the hit probability
The effect of radiation on materials, including live tissue, depends on the
quantum energy of the radiation and its type – alpha, beta or gamma. There
are other types of radiation, but these are seldom met outside a research
laboratory and we can omit them without distorting the story. Nuclear
photons are the same as the everyday variety emitted by atoms in street
lamps, LEDs or red-hot materials. Beta rays and regular electrons are also the
same – the different name only distinguishes their source; the same is true for
alpha particles and helium-4 nuclei. In fact each type of radiation is the same
in principle wherever it comes from – it has no memory of its emission, only
an energy and a type. If it shines into a piece of material from the outside as
an external source, or is produced as internal radiation from the radioactive
decay of atoms already within the material, that makes essentially no
difference to its effect either. What we need to know is where it is absorbed.
An important question is how far in material a quantum of radiation goes
112 Chapter 5: Absorbed Radiation and Damage
before it is stopped or absorbed – this is called its range. Some radiation
quanta or particles may pass clean through the material and out the other side,
while others will hit atoms in the material, may stop, or be completely
absorbed. Generally there is a considerable difference between types of
radiation as to how this happens, but less difference between materials.
Similar to the random timing of radioactive decay, the physics of whether a
particle hits a particular atom in the material is random, with a probability
determined by quantum mechanics. When an atom is hit by radiation in this
way, the action is entirely confined to its electron cloud that lies outside the
nucleus; the chance that the nucleus of the struck atom plays any significant
part is far too small to matter. This has the crucial consequence for radiation
safety: radiation shining on a material does not make that material
radioactive. This may not hold true at the high energies found only in a
research laboratory, or for a beam of neutrons. But neutrons are confined to
the core of a working reactor and only those materials that have spent time
there become radioactive from the effect of radiation.
Reactor fuel itself is not particularly active until it enters a working reactor
and absorbs neutrons. Similarly the cobalt steel that was used in the structure
of earlier reactors only becomes radioactive when regular cobalt-59 absorbs
an extra neutron and becomes cobalt-60. In the same way, hydrogen in the
water used to cool a working reactor core can absorb a neutron making
deuterium, which is not radioactive, and that in turn can absorb another
neutron to make tritium, which is mildly radioactive. None of these is made
outside the reactor, or even inside when it is shut down.
When a photon hits an atom the result is quite different from when an alpha
or beta particle does so. For a photon the whole of its energy is often
absorbed and the photon ceases to exist – in its previous form at least. The
random chance of a hit as gamma radiation passes deeper into material
depends simply on the number of photons that have not already been
absorbed, and this leads to an exponential distribution for the range of
individual quanta. This is sketched in Illustration 24, reminiscent of the
exponential distribution of radioactive decay, but in distance rather than time.
The probability of collision is the same for each atom, and so the chance of a
collision increases with the number of atoms, that is, with the thickness of
material that the radiation traverses. In principle this is similar for any
material, including living tissue. Incidentally, tissue behaves rather like water,
since that is what it is largely composed of, and its average density is about
the same.
Nuclear is for Life. A Cultural Revolution 113
Charged-particle radiation, including alpha and beta, has a rather different
effect on materials. Quantum mechanics shows that compared with gamma
radiation, there is a relatively large probability of a hit, but with a small
energy deposition when such a hit occurs. After a hit the charged particle then
continues on its way with an energy only marginally reduced. However, after
thousands of such hits its energy finally runs out and it simply stops. The
result is that a group of charged particles with the same energy have almost
the same range, and the statistical fluctuations, which are the basis of the
exponential distribution for photons, are almost absent. This gives a sharp
spike for the range distribution as sketched in Illustration 24.
For a given initial energy, alpha radiation has a particularly short range
compared with beta because the hit probability is very much higher, simply
due to its low speed and higher charge [19]. In fact alpha radiation is stopped
completely by skin or a few centimetres of air.
A famous photograph of Queen Elizabeth II on a visit to the nuclear
laboratory at Harwell early in her reign shows her receiving a bag of
plutonium and being invited to feel its warmth [20]. Her safety depended on
the sharply-peaked distribution to the range shown in Illustration 24. If alpha
particles had an exponential range distribution like photons some penetration
of the bag would be expected. In fact she was then, and remains now,
perfectly safe from the experience. Thanks to the unreasonably excessive
caution of modern safety regulations, such a ceremony would not be allowed
today. Now safety authorities are risk-averse and no longer act with science-
based confidence.
Illustration 24: Two simplified graphs illustrating the difference
between an exponential range distribution, e.g. for a photon or gamma
ray, and a sharply peaked range distribution for a charged particle
such as alpha or beta.
114 Chapter 5: Absorbed Radiation and Damage
The well-defined range of alpha radiation that protected Queen Elizabeth was
deadly for Alexander Litvinenko [21]. He was assassinated in London in 2006
by being given a pot of tea laced with between 100 million and 300 million
Bq of polonium-210 which he ingested. Like plutonium-239, polonium-210
is an alpha emitter (see Table 2). Polonium was named by Marie Curie after
her native Poland and she was awarded the Nobel Prize for its discovery in
1898. The range of the alpha radiation it emits when it decays is only 3.69 cm
in air, so all the radiation was absorbed within Litvinenko's body and he died
of Acute Radiation Syndrome (ARS) after three weeks, on 23 November.
Lack of discrimination in radiation damage
What happens to the absorbed energy at the point where a hit by ionising
radiation occurs? We have already seen that the nuclei of the material are
really not involved: it is the electrons which form the outer structure of each
atom and bind them into molecules that are affected by the impact. Whether
the radiation is a charged particle or gamma, the mayhem that is left at the
site of a collision consists of electrons, freed to wander off, and smashed
pieces of molecule. These are often electrically charged, having lost or gained
electrons in the melee. The energies typical of radiation, whether alpha, beta
or gamma, are in the MeV range, considerably larger than the weak bonds of
a small fraction of an eV that stabilise the state of molecules in their
biological role. This is the reason that radiation damage is indiscriminate and
much the same for any material. Atoms and molecules of all types are equally
liable to be damaged and there are no special cases.
The immediate damage at each hit is localised, for instance on a single
molecule, often with an electron expelled by the impact that then speeds off
to stop further away. After the collision the broken molecule or ion will
usually have considerable pent-up energy that is capable of creating further
mayhem. Such a molecule is called a reactive oxidant species (ROS). With its
energy it can ionise, break or excite other hitherto undamaged molecules,
creating a trail that may reach nearby cells before it runs out of energy. This
is an entirely chemical process, does not involve the nuclei and is
independent of the radiation that started the process. The initial hit
probability and everything that happens to the energy deposited in the
material in the first fractions of a second are linear – its effects simply add up
on top of one another. Any secondary electron or photon produced at the
initial hit site with enough energy may be the source of further hits as a
radiation track in its own right. With alpha and beta radiation such
secondaries are less frequent, but with gamma radiation a secondary photon
may carry energy some distance away to further sites until all energy is
absorbed. None of this is affected by whether the material is living tissue or
not.
Nuclear is for Life. A Cultural Revolution 115
Role of oxidants in damage to living tissue
In cellular tissue these secondary chemical effects caused by ROS radicals
are especially significant for their effect on DNA. Simply put, living tissue is
composed of many cells containing mostly water with various proteins that
are the structure and functional workhorses of every biological cell. Also
within each cell is a nucleus that contains the DNA responsible for creating
and controlling the proteins. Only damage to the DNA is a matter of long-
term concern. Provided that the DNA is not disrupted the other molecules
that may be damaged by radiation are regenerated by the cell replacement
cycle without lasting effect.
Since the effect of radiation is quite indiscriminate, it is water that suffers
most from the initial hits, simply because it makes up more than half of the
tissue mass. So, although DNA is occasionally damaged by direct hit, most
damage is due to the secondary chemical effect of ROS fragments of water
(H2O) attacking DNA. These fragments include such dangerous reagents as
hydroxyl (OH), hydrogen peroxide (H2O2), oxygen itself and their ions. It is
reasonable to assume that this damage is linearly related to the energy
absorbed because each physical process is independent and determined by
quantum mechanics. Therefore, the combined initial effect can be found by
adding up the independent contributions from each molecular hit – that is
using the linearity principle.
It is often irrelevant that the damage was initialised by radiation. Other
processes that produce these ROS cause damage to living cells in the same
way. In particular, since the metabolic process of oxidising food provides the
energy source for cells, accidental oxidation is a threat that biological cells
have always had to live with. In each cell the mitochondria organelles burn
the sugars and produce energy for the cell as a whole – these organelles must
prevent any ROS produced in this oxidation from reaching the cell nucleus
with its DNA. Inevitably some of these pollutants leak through and these are
just as damaging to DNA as those from ionising radiation. In particular, ROS
production increases with the extra energy production needed for normal
muscular exercise and cognitive activity [22]. The ROS produced by an
exposure to radiation over a period, a chronic dose, are a small addition to
these natural processes and generally not distinguishable from them.
However, a large acute radiation dose received in a short time is more
damaging, as is excessive physical exertion.
High LET radiation
The damage to any material immediately after the absorption of ionising
radiation consists of a distribution of these hits spread in space. Different
types of radiation produce characteristic distributions: gamma rays produce a
116 Chapter 5: Absorbed Radiation and Damage
sparse scatter of random hits; beta rays produce sparse hits lying along the
paths followed by the energetic electrons; alpha rays give dense lines of hits
lying along the track of each ray. This is called high LET radiation, with LET
standing for Linear Energy Transfer, also known as dEdx in nuclear and
particle physics [19]. The double charge and slow speed of alpha particles
cause the high LET. On the other hand the single charge and high speed of
beta particles of a similar energy give low LET. Gamma rays give a wide
distribution of hits so that they behave as low LET.
Living tissue is different from other materials because it reacts actively to the
initial damage. This reaction takes place partly within individual cells and
partly organically through the cooperative reaction of many cells. The hits
from beta and gamma radiation are sufficiently far from one another that the
subsequent biological response of repair and replacement at each hit can
proceed independently without saturation. But at high LET the density of
initial damage is so high locally that cells run out of the repair and
replacement resources required. In particular the density of Double Strand
Breaks (DSB) of DNA is enhanced. These are more difficult to repair, and the
biological tissue suffers somewhat greater long-term stress than for the same
absorbed energy at low LET.
Detecting radiation
Natural detection in living tissue
Darwinian evolution has provided us with a level of natural sensitivity to
In a truly linear theory there would be no such enhancement of the effect
of high LET radiation. The acknowledged enhancement at high LET is
accommodated in the LNT theory by assigning ad hoc weighting factors
built into the calculation of damage in sievert. This arbitrary modification
is applied in the LNT theory without explanation.
In a non-linear picture we may understand what happens. The local
energy density of high LET is seen to impose a greater load on local
repair and replacement mechanisms than the greater spatial uniformity of
low LET. This argument suggests a spatial scale – if the repair services
were available at any distance, there would be no dependence on LET.
This spatial scale typically extends to groups of cells, signalling and
cooperating together – or failing to do so when collectively overloaded.
This range for repair in the spatial picture plays a role similar to the repair
time in the time domain. Both are characteristic features of an active non-
linear response, one localised in space and the other in time.
Nuclear is for Life. A Cultural Revolution 117
some sources of danger but not to others – for these we look to instruments or
other strategies. We need to find out whether we are naturally sensitive and
act accordingly. A familiar example is household gas: mixed with air it is
explosive, but it is colourless and odourless. In a primitive evolutionary
environment, having a sensitivity to natural gas would bring no advantage in
the struggle to survive, and so evolution has made no such provision. In the
modern world safety is ensured when the utility company adds a trace of
another gas, t-butyl mercaptan, that does have a notably strong smell. This
makes household gas routinely detectable to the nose, so providing a simple
and effective addition to safety.
Similar methods help everybody to avoid the dangers of biological waste – in
this case courtesy of nature rather than the utility company. Evolution has
made human noses peculiarly sensitive to the gases given off by faeces and
urine for just this purpose. You might even say that the smell is in the nose of
the smeller, not in the polluted air that he breathes. What smells good, bad or
indifferent has been tuned by evolution only to enhance human survival
prospects. For example, dogs enjoy entirely different ranges of pleasant and
unpleasant smells, much to the occasional disgust and social embarrassment
of their owners. Vermin and lower biological agents have sensitivities, each
tuned to their niche in the hierarchy.
There are many other examples of natural protection: our eyes are safe from
the effect of steady bright light as is evident on the occasion of a solar
eclipse. There is a natural temptation to look directly at the Sun, and health
warnings are broadcast advising the public that this is dangerous. In practice,
however, there are few such accidents because pain makes people quickly
aware of excessive light in their eyes. Similarly, with non-ionising radiation
at high-power levels, its heat is felt before it becomes dangerous.
But what about ionising radiation? May we get a heavy dose from its rays
and not even know until it is too late? Why are humans not aware of ionising
radiation, naturally? Is the failure to provide sensitivity to ionising radiation a
rare oversight of Darwinian evolution? Would it not bring advantages? This
is a proper question and the basis of genuine concern for many people. Let's
look at the question. Biology would find the task challenging because the
energy fluxes are in the microwatt range and any sensitivity would be liable
to false alarms. As well as acquiring sensitivity to radiation we would like to
be cured of the damage that it does to living tissue. Even though a simple
electronic device is sufficient to say when and where ionising radiation is
present, it would not provide for the repair of any damage caused. Evolution,
it seems, has provided neither detection nor repair.
But in fact nature has been cleverer than this discussion has so far suggested.
The natural detection of ionising radiation damage by living tissue has been
118 Chapter 5: Absorbed Radiation and Damage
integrated with appropriate repair and replacement mechanisms. The
messages of a radiation attack on life and the subsequent actions are quite
subconscious and devolved down to the cellular level. If the body is attacked
by ionising radiation – and this is happening all the time to some extent – the
brain is not made conscious of it, and does not need to be, because the
problems are detected and remedied at the cellular level, at the front end, you
might say. We are mistaken if we ignore this biology while imagining that
regulations control radiation safety [23].
There are three reasons for this brilliant integrated biological design:
•Life has evolved in many forms from single-cellular organisms
through cabbages to primates – and recently humans. From the
beginning, radiation and other sources of oxidation have been a
source of danger that required detection and repair for all organisms,
including those without a brain or even a central nervous system.
•If the central nervous system were made aware of the inter-cellular
chemical signals that are triggered by a radiation attack, it would be
overwhelmed by the high rate of false alarms caused by other
oxidative processes. One may think of a domestic smoke alarm that
is sited too close to the kitchen toaster – it causes frequent false
alarms, until someone disables it. Such an alarm does not give an
organism a selective advantage.
•Providing local repair and replacement mechanisms, integrated with
local detection for all forms of oxidative attack, makes for devolved
robustness and independence of different parts of a large organism
with reduced lines of communication.
The result is that this superior devolved cellular safety system makes it
simply unnecessary for humans to be alarmed by ionising radiation at low
and moderate dose rates. That is as well since for the first 3,000 million
years, there was no cognitive ability to respond to a radiation alarm.
Unfortunately official radiological protection policy ignores what nature has
provided and tells the public that it should worry about such levels of
radiation. Adding a cautious and extreme regulatory regime on top of the
natural one is a mistake, similar to ignoring the old adage, Don't keep a dog
and learn to bark yourself.
Detection with man-made instruments
But how about instruments that detect radiation? It is not difficult to build
such a device and these may be simple or powerful, small or bulky. When
Henri Becquerel discovered nuclear radiation he used a photographic plate.
Our eyes are sensitive to colour only from red to violet, but a photographic
Nuclear is for Life. A Cultural Revolution 119
plate has a sensitivity to much of the spectrum, shown in Illustration 22, that
extends from visible light onwards through ultraviolet to X-rays and beyond.
A modern electronic camera can also be used to detect ionising radiation,
although thicker detection materials have to be used if the radiation is not to
pass through without giving a signal. An example of this is a clinical X-ray
picture in which the radiation passes through the body with only the heavy
calcium of the bones casting a shadow. A modern CT scanner uses X-rays in
a similar way. If gamma rays with too high an energy are used instead of X-
rays, even the bones do not show up much. The answer is to choose a photon
energy which shows contrasting absorption in the patient but is captured
efficiently in the detector material, whether photographic film, electronic
semiconductor or heavy transparent crystal. The best material for this is one
with the highest atomic number, in which the electron density is high and the
electrons are tightly bound.
Beta radiation, like photons, is easily detected by an ionisation detector
containing gas or a solid-state semiconductor. Alpha radiation is more
difficult because it is absorbed so readily. Often it is stopped by air or the
window of the instrument before it can be detected.
You may be thinking that you do not have access to such specialised and
expensive technology, but that is untrue. For fire safety you probably have a
domestic smoke detector. If not you can get one at a hardware store for about
US $10. Inside is a radiation detector with a radioactive americium-241
source made from nuclear waste. If you open it up and take a look yourself,
you will find the radiation symbol with details of the source. As a smoke
detector it is fail-safe because any smoke in the air absorbs the ionisation
from the radioactive source – the alarm triggers when it stops detecting
radiation from the source. Without the source it could easily be redesigned as
a cheap radiation alarm. Radiation is as easy to detect as burnt toast you
might justifiably say. Why are most radiation detectors not so cheap to buy?
If people wanted to buy them, they would be cheap – it is just a matter of the
market. One could be incorporated into every mobile phone – indeed, I
believe that such a phone is now available in Japan.
Professionals may say that is not good enough because it does not tell the
type of radiation: alpha, beta or gamma. That is true, and most radiation
detectors are quite unable to measure doses with any precision. But that
misses the point, because all you should need to know for peace of mind is
Modern detectors use exotic transparent crystals like bismuth germanate
(BGO) and lead tungstate. Then, not only are photons detected efficiently,
but the light-emitting cascades created within the crystal are tightly
confined.
120 Chapter 5: Absorbed Radiation and Damage
whether there is an excess of radiation of any kind present. That is the same
kind of simple question that you ask of your fire alarm. Provided that the
alarm is raised promptly and efficiently, further investigations can then be
made.
Notes on Chapter 5
1) Radiocarbon dating of the Shroud of Turin Damon et al (1989)
https://www.shroud.com/nature.htm
2) South Tirol Museum of Archaeology http://www.iceman.it/en/node/247
3) http://www.findingdulcinea.com/news/science/2010/mar/How-Do-You-Spot-
Vintage-Wine--It-Has-Fewer-Radioactive-Particles.html
4) In fact the beta decay energy of tritium is lower than that of any other known
nucleus.
5) The high doses given in radiotherapy are an exception. There differences of a few
percent may affect the success of the treatment.
6) Unlike radioactive decay biological excretion may not follow a simple
exponential loss if several mechanisms are involved.
7) Japanese Government Regulation on Beef (July 2011)
http://www.kantei.go.jp/foreign/kan/topics/201107/measures_beef.pdf
8) Japanese government regulation for caesium April 1, 2013: foods in general (100
Bq/kg), foods for babies (50 Bq/kg), milk (50 Bq/kg), drinking water (10 Bq/kg).
Note that for foods in general the regulations are 1,250 Bq/kg in EU and 1,200
Bq/kg in USA, for milk and drinking water 1,000 Bq/kg in EU and 1,200 Bq/kg
in USA
9) Norwegian food regulation after Chernobyl Harbitz (1998)
http://cidbimena.desastres.hn/pdf/eng/doc10879/doc10879-contenido.pdf
10) Sixteen years have passed since ...Swedish Radiation Protection Authority
Swedish press, Dagens Nyheter (24 April 2002). (English trans.)
http://www.radiationandreason.com/uploads/dagens_nyheter_C3D.pdf
11) WHO on levels of radioactivity in drinking water in Japan (2011)
http://www.who.int/hac/crises/jpn/faqs/en/index8.html
12) TEPCO notice of water discharge at Fukushima (5 April 2011)
http://www.tepco.co.jp/en/press/corp-com/release/11040508-e.html
13) US NRC on water safety (2014)
http://pbadupws.nrc.gov/docs/ML1326/ML13263A306.pdf
14) On 2 Sept 2015 TEPCO reported that groundwater discharges to the ocean have
been reduced to below 3 Bq/kg (caesium) and 1,500 Bq/kg (tritium). WHO
drinking water guidelines are 10 Bq/kg (caesium) and 10,000 Bq/kg (tritium).
15) Ignoring variations in conditions and the different effects of the UVA, UVB and
UVC spectral ranges into which the ultraviolet spectrum is divided.
16) US statistics on skin cancer (2011) http://www.cdc.gov/cancer/skin/statistics /
17) US statistics on death by fire (2011) www.usfa.fema.gov/data/statistics/
18) US statistics on death in highway accidents (2013)
http://en.wikipedia.org/wiki/List_of_motor_vehicle_deaths_in_U.S._by_year
Nuclear is for Life. A Cultural Revolution 121
19) Fundamental Physics for Probing and Imaging Wade Allison, OUP (2006)
20) Story of plutonium Nuclear Engineering International (2005)
http://www.neimagazine.com/opinion/opinionthe-drama-of-plutonium
21) Polonium-210 as a poison Harrison J. J Radiol Prot. (2007).
http://www.ncbi.nlm.nih.gov/pubmed/17341802
22) Exercise-induced .... oxidation Fogarty et al. Environmental ... mutagenesis 52, 35
(2011) http://onlinelibrary.wiley.com/doi/10.1002/em.20572/abstract
23) Notably in 2015 the Nobel Committee gave the Prize in Chemistry for the
elucidation of such DNA repair mechanisms.
Nuclear is for Life. A Cultural Revolution 123
Chapter 6: Effect of Large Radiation
Doses
Brian: Look, you've got it all wrong! You don't need to follow
me. You don't need to follow anybody! You've got to think for
yourselves! You're all individuals!
Crowd: [in unison] Yes! We're all individuals!
Brian: You're all different!
Crowd: [in unison] Yes, we are all different!
Man in crowd: I'm not.....
Crowd: Shhh!
From Monty Python's Life of Brian
Weighing scientific evidence
Rise and fall of enthusiasm for science 124
Examining the strongest evidence 124
When radiation is fatal, sooner and later 125
High internal radioactivity, the accident at Goiania
The effect of intense internal radiation 127
The accident, 13 September 1987 127
Casualties and internal radioactivity measurements 129
Comparison to public measurements at Fukushima 130
Civil order and psychological effects 131
Effect of the accident at Chernobyl
Places where time stood still 132
Scale of accidents 132
Effect on local mental health 134
Mortality from radiation 134
Death from Acute Radiation Syndrome 135
Cases of child thyroid cancer 136
Loss of life caused by fear 137
Mistakes at Chernobyl repeated at Fukushima 138
Chronic and protracted doses, radiotherapy
Dose rates, time scales and whole-of-life doses 138
Experimental data on mice, dogs and humans 139
Cancer caused by radiotherapy for an earlier cancer 140
124 Chapter 6: Effect of Large Radiation Doses
Living with artificial radioactivity 141
Living with natural radioactivity 141
Effect of intense chronic alpha radiation
The life of Marie Curie 145
The Radium Dial Painters and litigation 146
Safety of plutonium as a new element 148
Extreme experiences, Litvinenko and McCluskey 150
Uranium – natural, enriched and depleted 151
Notes on Chapter 6 151
Weighing scientific evidence
Rise and fall of enthusiasm for science
Nobody knows who did it or when it happened. It may have been in
Mesopotamia, or possibly early in the Greek era, that astronomers first
successfully predicted a solar eclipse. As a demonstration of the power of
mathematical science, it must have impressed the whole population. But
respect for the word of science when established through awe and fear is not
a sympathetic basis for understanding.
At a practical and political level it became apparent that making other useful
predictions was not so easy, and physicists and astronomers had to accept
defeat when they tried to extend their new-found powers to turning base
metals into gold; similarly vain attempts in astrology caused the popularity
ratings of science and scientists to wane. Scientific enthusiasm has always
coexisted with a primitive awe and apprehension of natural phenomena; it
has improved with education and successful prediction, but retreated under
the influence of war, accident, pestilence, earthquakes, rumour, ignorance and
the vagaries of the weather. So, while science slowly advanced, many natural
phenomena became either deified or demonised by the public at large. For
example, thunder and lightning remained a source of primitive fear that
diminished only slowly as a deeper understanding of science percolated into
society from the nineteenth century onwards. However, human prosperity has
only really improved since confidence and a command of natural processes
have become established.
Examining the strongest evidence
Members of the public are motivated by simple direct questions such as.
Is there a danger that could affect me, my family and friends?
Nuclear is for Life. A Cultural Revolution 125
They are less impressed by calculations and machinations they are unable to
follow, and they are suspicious of regulations and restrictions which they see
as a cover for higher prices, taxes, professional career building or political
manoeuvring.
But ionising radiation has been in use for over 100 years in medicine, and for
over 70 years in other spheres. So there is plenty of experience to draw on.
Down-to-earth common sense answers can be given that do not rely on fancy
mathematics or science. But it is not sensible to look at every source of
evidence. It is better to concentrate only on the most significant; that means
the most persuasive. Let's clarify this line of thought a little further.
The statistical significance of a result is poorly understood, with the result
that weak conclusions get into the media and then have to be withdrawn, or
worse, fail to be withdrawn. That commands no respect and should not
happen. It was notable that prior to the report of the discovery of the Higgs
Boson at CERN, there was an information blackout until the significance of
the discovery could be confirmed at five standard deviations – a level of 1 in
a million and representing confidence beyond reasonable doubt.
Unfortunately, putative results in medical and biological sciences are seldom
subjected to such strict tests and some conclusions are reported to be firmly
established when at the level of only two standard deviations – in everyday
language, that means 95% certain, or wrong 1 time in 20. Claims at such a
weak level of confidence, a 5% chance of being mistaken, would lead to a
rejection by referees for many scientific journals in other disciplines.
Dubious results when picked up by the press become sources of confusion –
what the press like to call matters for debate. But the press do not have the
means to engage in such a debate. If the evidence is not strong enough to
establish a firm result, all should agree to remain silent until further evidence
becomes available. In the remainder of this chapter, we look at results that are
widely accepted as beyond reasonable doubt.
When radiation is fatal, sooner and later
At a very high dose rate, radiation can kill not just cells or organs but whole
organisms, and by examining data we can find out just how high the rate
needs to be for this to happen. Radiation can be fatal in one of two ways. It
can destroy the ability of a cell to service itself and engage in the cell cycle;
this is called cell death. If too many cells are killed in this way the entire
organism may be at risk from Acute Radiation Syndrome (ARS). This has
nothing to do with cancer and takes place on the time scale of a typical cell
cycle, that is within a few weeks at most. There is some difference between a
dose given to the whole body and one applied only locally, but most organs
fail due to the local dose when their own cells die independently of the fate of
other organs. Some radiobiologists speak of cell death as a deterministic
126 Chapter 6: Effect of Large Radiation Doses
process, but actually it is a biological reaction described by a probability like
any other process – though that probability may be high for a large acute
dose. Other historical descriptions: tissue reaction and early reaction, are
descriptive and more helpful.
Most cells with damaged DNA are either repaired correctly by enzymes
within hours or are repaired with errors such that they are not viable and fail
to be reproduced in the cell cycle. However, a few of those that suffer DNA
double strand breaks (DSB) are incorrectly repaired and yet survive. These
mutations may persist in abnormal chromosomes whose behaviour is kept in
check by the immune system. Failure of the immune system may result in
runaway cell growth that hijacks the resources of the organism; this is the
malignancy that we know as cancer. In its later stages such growth may go on
to metastasise or spread through the blood stream to other locations and
organs. With advancing age the immune system becomes less vigilant and
errors may escape detection. The process is similar whether the error was
initiated by radiation or another source of chemical oxidation. The probability
that cancer develops is small and therefore apparently rather random, so it is
sometimes called a stochastic process, although it does not involve any
special kind of chance mechanism at a basic physical and chemical level. The
description late reaction is less committal. We concentrate on cancer because
data on late reaction for other diseases is usually less clear. The evidence
shows that carcinogenic development is related more to the failure of the
immune system than to the presence of an increased number of damaged
chromosomes. The period in which the development of malignancy is kept in
check by the immune system is called the latency.
Tumours develop at or near the site of the original radiative or oxidative
attack – for example, smoking causes primary cancer of the lung and UV
radiation causes primary skin cancer, rather than cancers elsewhere. This
suggests that, although whole-body health is always an important factor, it is
the local radiation dose rather than the whole-body dose that is important.
This intuitive picture is supported by recent detailed clinical work reported
by Tubiana and described in Chapter 8.
A malignant tumour develops at the expense of the host organism; it hijacks
resources and physically invades the local tissue. The resulting disruption of
the local blood vessels may be diagnosed with a functional imaging scan. If
not removed or its cells killed, the tumour eventually metastasises, migrating
through the bloodstream to establish further tumours elsewhere in the body. It
may be removed surgically, or its cells treated by targeted radiation or
chemical drugs. This may also be achieved with focussed ultrasound that
destroys the cells of the tumour tissue by overheating – cooking, in fact. Even
after it has spread, the progress of the cancer can still be reduced with
radiation or chemotherapy. Such palliative treatment can extend life, even
Nuclear is for Life. A Cultural Revolution 127
though the cancer survives.
High internal radioactivity, the accident at
Goiania
The effect of intense internal radiation
It is not a surprise that particular concern should be expressed about
radioactivity inside the body. What data do we have and what can they tell us
about any threat that this poses to the residents of Fukushima, now or in the
years to come?
There is general agreement among international bodies that there is no
significant evidence that radioactive caesium was responsible for any death at
Chernobyl, either of identified individuals or of members within a group
analysed statistically [1]. However, it was responsible for several deaths in an
accident with a caesium-137 source in the provincial town of Goiania, Brazil,
in 1987 [2, 3, 4]. But what was this very intense source doing there?
The radiation used to cure cancer by radiotherapy is no different from that
present in a nuclear power plant, although the intensity used for therapy is far
greater than that around a reactor except inside the vessel itself. The intensity
of the therapy dose is designed to kill the cancer cells directly in its path by
repeating the dose every day for 5 to 6 weeks. The radiation used in therapy
may come from a radioactive source, either external or internal to the
patient's body; alternatively it may come as a beam emitted by an accelerator
in the therapy clinic shining onto the patient. The latter is preferred, simply
because the radiation can be turned off by unplugging the accelerator and its
beam can be steered in a particular direction. Although a gamma beam cannot
be focussed or deliver energy at a specific range, a beam of charged ions used
in the most modern radiotherapy can do both, so that the dose is confined
very precisely to the tumour [see Selected References on page 279, SR3].
However, away from the world of modern technology a brief exposure to
radiation from a powerful radioactive source is cheaper and simpler to
provide. Well shielded sources have been used for over a century since
pioneered by Marie Curie. As with the accelerator method, a powerful dose
must be delivered in a short time.
The accident, 13 September 1987
The gamma source that had been used in the now-abandoned radiotherapy
clinic at Goiania was caesium-137, which as a major constituent of
radioactive waste, was readily available. Chemically, caesium is like sodium
or potassium and relatively volatile. It is the most persistent contaminant of
food and the environment after an accident such as at Fukushima and
128 Chapter 6: Effect of Large Radiation Doses
Chernobyl. (In fact it is accompanied by another isotope, caesium-134, but
we need not worry about that here.) The other contaminant, iodine-131, has a
half life of 8 days, whereas caesium-137 has a radioactive half life of 30
years. But if caesium is inhaled or ingested into the body, it is expelled again
with a biological half life of about 100 days because caesium, whether
radioactive or not, is not a natural constituent of the body's biology.
Illustration 25: A map of Brazil showing the location of the
provincial city of Goiania, just west of the capital Brazilia.
The shielded caesium-137 source that had been used to treat cancer at
Goiania had an activity of 50.9 TBq. The T of TBq stands for Tera, or a
million times a million; that is a trillion. This activity is 500,000 million
times the activity of a litre of water described by the Japanese regulations of
2012 as unsafe to drink at 100 Bq. But in use, the caesium-137 source was
held securely in the shielded steel head which, when rotated to the ON
position, would deliver 4,600 mGy per hour, suitable to treat a tumour.
By 1987 the source at Goiania was abandoned. It was removed together with
its protective housing from the radiotherapy machine by some locals, hoping
to make money by selling the steel of the unit for scrap. Having removed the
head the gang took it home in a wheelbarrow and broke it open to reveal the
source itself – 0.93 kg of caesium chloride powder. The two men were then
exposed when they worked on the source and started to feel ill with
Nuclear is for Life. A Cultural Revolution 129
diarrhoea, vomiting, dizzy spells, and swollen hands. On 18 September they
punctured the thin window with a screwdriver and the parts of the rotating
source assembly were sold to the owners of the scrapyard next door. In their
garage the source was seen to emit a pretty blue light, and over the next three
days relations, friends and acquaintances visited to see the curiosity. On 21
September they extracted some powder, and distributed it to friends and
visitors, some of whom daubed it on their skin. From 22 to 24 September two
employees worked on the head to extract the lead. On 24 September
fragments were taken into the house and handled during a meal, notably by a
six year old girl, and then the source was sold to another scrapyard. By this
time many people were ill and the remains of the source were taken to a local
hospital, where the next day doctors were able to contact a medical physicist,
who succeeded in raising the alarm after detecting the radiation with a
borrowed detector designed for geological prospecting [2].
Whole-body internal radioactivity Number
of people
Radiation
deaths
Goiania [2]
Cs-137 more than 1,000 MBq 1 1 death, ARS
Cs-137 100 to 1,000 MBq 7 3 deaths, ARS
Cs-137 10 to 100 MBq 20
no death,
no radiation
cancer
Cs-137 1 to 10 MBq 23
Cs-137 100,000 Bq to 1 MBq 15
Cs-137 10,000 to 100,000 Bq 11
Fukushima
adults [6]
Cs-137 12,000 Bq or less
Aug 2012
32811
Everybody,
natural K
K-40 4,300 Bq all
humans
Fukushima
children [6]
Cs-137 all less than 1,400 Bq
Nov 2011 - Feb 2012
1491
Table 4: Figures for whole body caesium-137 radioactivity at Goiania,
compared to Fukushima (and to its natural look-alike, radioactive
potassium-40, present in all life). Measured Fukushima limits should
be increased by a factor 5 to 10 to account for the time lapse before
measurement (given in the Table).
Casualties and internal radioactivity measurements
By 28 October eight people had contracted ARS, of whom four were dead.
Altogether 249 people were directly affected by the radiation, externally or
130 Chapter 6: Effect of Large Radiation Doses
internally. In 28 cases localised contamination and irradiation gave rise to
deep burns on limbs and body, many requiring surgery. However, internal
contamination gave the most significant exposures, with protracted or chronic
doses persisting over a long period. Once caesium enters the blood stream, it
is taken up throughout the body, particularly in muscle. The natural excretion
period of caesium is about 100 days. The measured values of the whole-body
internal activity for over 70 patients have been published by the IAEA [2, fig.
13 p. 55]. These are shown above in the unshaded bands of Table 4, arranged
in order of decreasing activity.
Comparison to public measurements at Fukushima
The right-hand column of Table 4 shows that all fatalities had a whole-body
internal activity exceeding 100 MBq, although half of those between 100
MBq and 1,000 MBq survived. Notably, in the 25 years since the accident,
there has been no case of cancer in any band that could be attributed to
radiation [5]. The shaded bands describe other data for chronic internal
radiation, in particular those relating to the survey of adults and children in
the affected Fukushima region [6] (see the mobile unit, Illustration 16 on page
51). Evidently, even the highest whole-body measurement of a member of the
public recorded in the Fukushima region is at least 10,000 times smaller than
the lowest internal dose that was fatal at Goiania, noting that none of those
fatalities was due to cancer in any case. Also shown in Table 4 is the natural
radioactivity due to potassium-40 present in all life. Potassium and caesium
have very similar chemistry and therefore circulate around the body in the
same way. However, irradiation by potassium-40 is chronic because it is
included in all potassium in the environment – most famously in bananas [7].
This underlines how genuinely inconsequential small doses of radiation are –
and even much larger ones too.
There are quite proper questions about the effect of internal radiation on
pregnancy, but the data from Goiania offers some extraordinary answers too.
One woman, already four months pregnant at the time of the accident, had an
intake of 200,000 Bq and gave birth normally – both she and her child were
radioactive, but this continued to decline by a factor two about every hundred
days after the birth. Another woman who survived and had one of the highest
internal intakes, 300 MBq, an activity as great as two of those who died of
ARS, gave birth to a healthy child four years and three months after the
accident [5, p. 47]. These data are very reassuring. Broadly they support for
humans the conclusions found from experiments with mice [8] that
pregnancies and foetuses are not as radiation-sensitive as is usually
presumed.
The conclusion is that very large internal doses of caesium-137 had no direct
carcinogenic effect over a 25-year period and that the possibility of cancer
Nuclear is for Life. A Cultural Revolution 131
from internal radiation by caesium at Fukushima is negligible. The number of
people that were contaminated at Goiania is not high, but the internal activity
that many of them received is very large. The woman who had the healthy
child after four years had the same internal activity after the accident as she
would have received if she had drunk three million litres of water with the
contamination of 100 Bq per litre, condemned, without justification, as
unsafe at Fukushima. At 10 Bq per litre, the upper permitted limit for
drinking water as at April 2013, the volume of water would be thirty million
litres, that is twelve 50-m olympic swimmming pools. For any reasonable
person these data should close the book on whether there is any risk at
Fukushima from caesium-137, even for foetuses, children and pregnant
mothers. There are other sets of data in the scientific literature [9], but none
that contradicts the conclusion that there is inadequate evidence for the
carcinogenicity of caesium-137 in humans [10]. (For simplicity we have
ignored the other isotope, caesium-134, that accompanies caesium-137,
although there is no evidence for its carcinogenicity either.)
Civil order and psychological effects
On 26 March 2012 Yukiya Amano, Director General of IAEA, wrote in the
Washington Post [11]
In one of the world’s worst radiological incidents, radioactive
material stolen from a disused clinic in Goiania, Brazil, in 1987
caused the deaths of four people, while nearly 300 suffered
radioactive contamination and more than 100,000 sought
radiological screening. That incident involved the unintended release
of radioactivity, but it remains the best real-world indicator of what
could happen on a larger scale if terrorists were to detonate a dirty
bomb in a large city or at a major public event.
This Goiania event may have been the world's worst such incident, but the
number of fatalities was like a single family car hitting a tree and all four
occupants being killed. Not an accident on a world scale. It was most
unpleasant for the 249 others involved or for the 100,000 who rushed to
receive a reassuring scan, but a general alarm would not have been justified.
To be fair, though there was an information vacuum and many were
frightened, there was no breakdown of law and order. Neither the Goiania
accident nor a terrorist dirty bomb presents a global threat, and the
Fukushima accident even less so, but the hysteria so quickly raised by today's
24-hour rolling media over such an incident could precipitate serious civil
disorder. Regrettably, that may not be what Dr Amano intended to say. He
appears to be talking up the seriousness of the accident itself, whereas it
would be in the public interest for the IAEA to concentrate on providing
proper education and information to the public in future, to reduce the fear
132 Chapter 6: Effect of Large Radiation Doses
and uncertainty that can easily follow such an accident.
In 2011 a study reported that 42.5% of those who had been exposed at
Goiania were suffering symptoms of depression, against 3% to 11% in the
general Brazilian population [6]. The damaging effect of psychological stress
in the community, so clearly seen at Chernobyl, and then repeated at
Fukushima, was evident at Goiania too.
Effect of the accident at Chernobyl
Places where time stood still
At some places on Earth the human imagination is carried away by a single
event frozen in time. A visit to Herculaneum or Pompeii, buried by volcanic
ash in AD 79, recalls such a time and what was happening then, down to the
smallest detail of everyday life, that would normally have been swept away
by the onward march of later trivia. At Portsmouth in the UK the new
museum of the Mary Rose houses another example, the flagship of King
Henry VIII, that sank in a few minutes in 1546 but was recently raised with
so many details of Tudor life preserved on board. In the same way a visit to
Chernobyl and the town of Pripyat concerns what happened on a single date,
26 April 1986. It tells a unique story, one that should be preserved although
its physical decay is already advanced. The environmentalist, Mark Lynas,
recently suggested that it should be a World Heritage Site.
Frozen though these sites may be, the understanding of their message can
mature, and so it has at Chernobyl. The site, deserted by human life at short
notice and now overgrown, was reported as a waste land and dangerous for
many years, but now in reality it is a wildlife park in all but name [SR7].
Flora and fauna are radioactive, but are no longer restricted by the disruptive
intervention of man. The animals, birds and plants flourish freely along with
the few human beings who stayed behind when others were evacuated
[SR11].
Scale of accidents
At Chernobyl the water-cooled graphite-moderated nuclear fission reactor
that exploded was designed and built by the Soviet Union [SR3 p. 73 & 141].
Unlike Western designs, including those at Three Mile Island and Fukushima,
it had no spherical containment vessel, so any release of radioactivity was
free to disperse into the atmosphere, and the control of temperature and rate
of energy production was not stabilised by a fail-safe design. On the day of
the accident the operators were ill-advisedly testing operating procedures
with important safety systems disabled. They lost control and the temperature
started to increase quickly. Soon the water, now steam, reacted with the
Nuclear is for Life. A Cultural Revolution 133
rapidly-heating graphite, creating hydrogen, whose pressure blew the top off
the reactor. This hydrogen then exploded in the air and the whole mass of red
hot graphite, now open to the sky, burned for days, sending much of the
nuclear material upwards. A brave band of 237 workers fought the blaze,
exposing themselves to the open reactor core, which was never shut down in
the way that those at Fukushima Daiichi and all the others in Japan were. At
Chernobyl the extreme heat of this open fire generated a rising column of
gases, carrying all but the heaviest nuclear material into the upper atmosphere
where it circulated around the globe. To put the comparison with Fukushima
into perspective you might ask what happened to the cooling water. After all,
that was the focus of attention at Fukushima. At Chernobyl none remained –
it had reacted to form hydrogen or been vaporised. Cooling? There was none.
There is no doubt that Chernobyl was the worst civil nuclear accident,
arguably the worst imaginable. The reactor had no containment vessel, unlike
most reactors of that era and every one since. At the time the government of
the Soviet Union was entering its dysfunctional phase prior to collapse, and
information was not made available – in fact it was the detection of the
radioactivity in Scandinavia that carried the news that there had been an
accident at all. In response to Chernobyl, IAEA introduced the International
Nuclear and Radiological Event Scale (INES) in 1989 to describe the severity
of an accident, for a purpose that is unclear. Anyway, Chernobyl was
retrospectively classified as 7, the maximum on the scale. Unfortunately, a
position on this scale is determined by the administrative judgement of the
authorities actually involved, rather than by an objective measurement like
that used by seismologists in assessing the strength of an earthquake. In the
case of Fukushima the Japanese authorities lost their nerve and gave it the
maximum, 7, like Chernobyl. This was a basic mistake that simply escalated
the public sense of panic. The Fukushima accident was never in the same
class as Chernobyl. An unscientific index like INES simply excites instability
in public opinion which is in the interest of nobody.
The question is sometimes asked, What should replace the INES scale? The
answer is simple, Nothing. There is no such scale for fossil fuel accidents or
the collapse of hydroelectric dams, although these involve the loss of large
numbers of lives, which is very rarely the case for nuclear accidents. Scales
of this sort fill no beneficial function. Why does anybody think that there is a
need for a scale? Perhaps because they still see nuclear radiation as
exceptional and needing extraordinary safety provision, but that is a political
reaction, unsupported by objective scientific evidence. The worst recent
accidents for a number of base-load energy sources are listed in Table 5. It
shows that nuclear energy is far safer than other competing sources.
134 Chapter 6: Effect of Large Radiation Doses
hydro Shimantan, China 1975 171,000 deaths
nuclear Chernobyl, Ukraine 1986 43 deaths
oil Jesse, Nigeria 1998 at least 300 deaths
natural gas Chuandongbei, China 2003 243 deaths
coal mine Soma, Turkey 2014 301 deaths
Table 5: Recent high-mortality accidents for base-load energy sources
[12].
Press reactions to such a calm assessment of the Fukushima accident have
included, But there was a triple meltdown!! Except in horror movies where
the science is adjusted to make the story exciting, a nuclear meltdown is
much preferable to a nuclear reactor that blows up, as happened at
Chernobyl. Even there, the effect of the radiation itself on people's lives was
very limited compared with accidents from other energy sources (see Table
5).
Effect on local mental health
At Chernobyl the local authorities were slow to act until the international
alarm forced them to acknowledge what had happened. Chernobyl is in a
poor area of Ukraine largely dependent on agriculture. So, unaware of the
accident, the country people continued to eat locally produced food,
absorbing radioactive fallout from vegetables and dairy products as they did
so. Then, suddenly and without notice, many of them were herded into buses
and evacuated to unfamiliar accommodation quite unsuited to their way of
life. Unemployed and ignorant of what had happened to them, the evacuees
and their families developed all the usual signs of severe social stress –
suicide, alcoholism, family break-up, increased smoking and hopelessness.
Mortality from radiation
Accounts of accidents record the details of injuries, lists of fatalities and
social consequences, even though these may not be known precisely. Also
important is the number of cases that would have happened anyway without
an accident. Exposure to radiation can result in eye damage and beta-burns to
the skin, similar to sunburn, although recovery from such conditions is
usually complete. However, at the time of the Chernobyl accident and for
many years thereafter, there was wild speculation that the number of deaths
that it would cause would be high – tens and hundreds of thousands – and the
reasons for this expectation were cultural and historical, as discussed on
Chapter 10. But after a lapse of 25 years it is now possible to set the record
straight and give generally agreed scientific estimates of the number of
Nuclear is for Life. A Cultural Revolution 135
deaths, and to understand the effect of the radiation in terms of modern
biology.
What do such numbers mean and how are they found? There are three types.
•First, there are the deaths of identifiable individuals who would
otherwise have lived. We do not need fancy mathematical statistics to
get the answer for them; we know who they are, individually by
name.
•Second, there may be a group that as a whole shows a significantly
larger number of deaths than would have been the case without an
accident, but for which it is not possible to distinguish the individual
casualties from those cases that would have occurred anyway. To be
confident that the radiation accident was a cause, two large groups
need to be compared which are similar, except that one was irradiated
by the accident and the other was not. Estimates of the number of
extra deaths and its uncertainty involve a statistical calculation. The
conclusion may be quite firm or it may be decidedly weak.
•Finally, there are those who might have died from the accident but
for whom no clear statistical evidence is available. This is a don't-
know situation and the evidence does not exist; it is dangerous just to
speculate in the absence of evidence. But in the early years after
Chernobyl it was possible to argue that one should wait and see.
After 25 years this is no longer reasonable and the conclusions of no
evidence are looking final.
Death from Acute Radiation Syndrome
At Chernobyl there was one group of individually identifiable victims. These
were the 28 men who died after fighting the fire at the reactor in the first few
days. Death was from ARS, not cancer, and the mortality among the 237 fire-
fighters in each dose range is shown in Illustration 26. The graph shows that
for those who received less than 4,000 mGy, labelled point A, the mortality
was only 1 in 195. At higher doses the mortality rises steeply and reaches
near 100%, point C, at around 7,000 mGy, point B. Evidently there is a
threshold in the region of 3,000 to 4,000 mGy and the data for rats described
by the smooth curve show a similar effect. All those who died of ARS did so
within a few weeks and the others recovered.
136 Chapter 6: Effect of Large Radiation Doses
A significant question is what happened subsequently to those of the 237 fire
fighters who survived early death by ARS. In 25 years in any such group
some would die anyway. The questions are whether more of them died than
expected, and whether the complaints that they died from have any
connection to radiation. The numbers are relatively small and so fluctuations
are expected. Nevertheless, the World Health Organisation has not reported
any significant signs or correlations among these closely monitored
survivors, suggesting extra cases of leukaemia, for instance [13].
Cases of child thyroid cancer
There was one small group of extra deaths that were identified, though only
statistically. The incidence of thyroid cancer in the regions of Ukraine,
Belarus and Russia near to Chernobyl showed an increase of about 6,000
among children [14, 15]. Some of these were unrelated to radiation (and so
would have occurred in any event) and others were detected prematurely
because they were screened intensively. Some may have been caused by the
ingestion of radioactive iodine-131 from vegetables and milk contaminated
by fallout. Iodine, whether radioactive or not, is concentrated into the thyroid
gland, especially in growing children. The uptake of iodine depends on the
supply of iodine in the local diet which may be poor, as it is in Ukraine, or
rich, as it is in Japan, where iodine-rich sea weed is eaten regularly. Any
radioactive iodine is diluted by the presence of regular iodine, whether from
normal diet or taken as a supplement. Radioactive atoms decay with a half-
life of eight days and then become harmless. So children born since the
Illustration 26: A graph of data showing for different radiation doses
the mortality of the 237 early fire fighters from ARS (crosses labelled
by number of deaths/total for each dose range). The curve is from
similar data for rats.
Nuclear is for Life. A Cultural Revolution 137
accident cannot be affected, and indeed they do show that the cancer rate has
returned to its normal low level. Thyroid cancer can be treated making use of
the same high efficiency with which iodine is concentrated by the thyroid. In
a course of therapy the patient is injected with much more radioactive iodine
that then kills the tumour cells. In spite of the increased reported incidence,
most cases were successfully treated and, as a result, the number who have
died from the radiation is not 6,000 but 15.
The intensive screening process caught some cases that would not have
developed and these cases were not caused by radiation. The extent of these
false diagnoses is debated. But if normal potassium iodide tablets had been
taken, as they were in many places in Japan, the number of real cases at
Chernobyl would certainly have been reduced. Given that the release of
iodine-131 at Fukushima was much smaller than at Chernobyl, no real
increase in the incidence of child thyroid cancer beyond that which would
have occurred without the accident is expected, and certainly no death.
There continues to be no evidence for any other fatality at Chernobyl caused
by radiation. In particular, in agreement with findings for the survivors of
Hiroshima and Nagasaki after 50 years, there is no evidence for any
increased incidence of deformity or inherited genetic effect [16].
Loss of life caused by fear
Fear of the radioactivity released in the Chernobyl accident spread far beyond
the evacuation zone and those labelled as sufferers. Concern about any
possible risk to later generations was reflected in increased abortion rates in
the following months in many countries, even those quite far away. In
Greece, for instance, this was evident as a sharp dip in recorded birth
statistics, indicating that there were 2,000 extra abortions there [17]. These
statistics indicate drastic personal action taken in response to the threat of
radiation, when in reality there was no danger at all.
As described in Radiation and Reason [SR3], social stress and fear of
radiation is now considered by the World Health Organisation (WHO) to
have been responsible for many deaths, although reliable numbers are not
available. The rural population near Chernobyl had little education or
experience of life in nearby towns and their disorientation was caused by
their hurried and unexplained evacuation. Officially labelled as victims of
radiation, a description beyond their knowledge and disconnected from their
sensory experience. They suffered from the threat of unknown disease, the
scramble for compensation and life in an unfamiliar place. These led
inevitably to general stress, dependency and hopelessness.
In 1986 the Cold War was not yet over and for a number of years the
international community continued to be so transfixed by the much-hyped
138 Chapter 6: Effect of Large Radiation Doses
dangers of radiation and radioactivity that they overlooked this suffering,
which was the most serious health outcome. It was not until 2006 that the
truth was fully acknowledged in international reports, the latest draft from
UNSCEAR being published less than two weeks before the Fukushima
accident [18].
Mistakes at Chernobyl repeated at Fukushima
These reports on Chernobyl by WHO, IAEA and UNSCEAR remained
unheeded by the authorities in Japan when the accident at Fukushima
occurred, and the mistakes of Chernobyl were repeated there. Why did the
authorities in Japan not have a plan of action? Why did they act seemingly
unaware of these reports? Their reaction is not uniquely Japanese, and it is
probable that the national authority in any other country would have reacted
similarly had such an accident occurred there. Instead of thinking for
themselves as they do when faced with an earthquake or tsunami, the
Japanese authorities turned for advice to the US Nuclear Regulatory
Commission (NRC). Why?
Advice is sought from higher authority for any threat that is not understood
or trusted, in Japan as elsewhere. Unfortunately the Japanese government
lacked both understanding and trust, and so consulted the US NRC. This was
unfortunate because it was headed at the time by Gregory Jaczko, who held
long-standing anti-nuclear views. Clearly he had not read and understood the
UN reports either, and the Japanese government seems to have received inept
and dangerous advice. Jaczko was replaced as head of the US NRC a year
later.
The Japanese people would seem to have been victims of their deferential
attitude to the US, an unfortunate outcome given the indigenous expertise in
Japan. Much of the finest scientific work on the beneficial effects of radiation
at low dose rates comes from Japan, but there is a culture of
compartmentalised responsibility, an unwillingness to make public comment
on any matter unless required to do so. But Japan is not alone in this and
other cultures suffer from the same paralysis of opinion. What distinguishes
Japan is its geology, and that is what caused the damage and loss of life, not
its use of nuclear energy.
Chronic and protracted doses, radiotherapy
Dose rates, time scales and whole-of-life doses
The permanent damage inflicted by a radiation dose spread out over a period
of time is quite different from that inflicted in an acute dose, a single dose all
at once. Even when the total dose, that is the energy deposited in joules per
Nuclear is for Life. A Cultural Revolution 139
kg, is the same, the extension in time alters the effect on the organism in two
ways. Firstly, although in a short period the resources needed by cells to
replace or repair temporary damage get rapidly used up, a dose delivered
over a longer period allows time for further resources to become available.
Secondly, it allows the cell (or cells) to adapt their readiness for any further
incident in the light of experience.
Here is an analogy. If an acute dose is like a sprint, a chronic dose is like a
long-distance run, and the adaptation is like the improvement over time that a
history of regular exercise builds up. Adaptation is least in response to an
acute dose, such as the flash of gamma rays and neutrons experienced by the
inhabitants of Hiroshima and Nagasaki. So the effect of acute and chronic
doses are different. A steady chronic dose rate is measured in mGy per day,
for example, while a single acute dose is measured in mGy, full stop.
Traffic accidents provide another analogy. These are related principally to the
speed at which vehicles travel, and less to the distance they cover. If distance
were related to accidents, the police might hand out tickets to motorists
travelling more than 15,000 miles, for example. But since distance is less
important than speed, and accidents do not accumulate with distance
provided the speed is kept low, the highway police only give tickets for the
rate of distance (that is the speed) over 70 miles per hour, say. Slower speeds
do not accumulate accidents, or speeding tickets.
Similarly, the evidence for the damage due to a radiation dose suggests that it
depends primarily on dose rate, not accumulated dose. The difference
between an acute and a chronic dose may be as obvious as the difference
between miles and miles per hour, but, nevertheless, they are frequently
confused.
As argued in Radiation and Reason [SR3], there are reasons to give chronic
dose rates a daily or monthly time-scale, for that is the scale of the biological
repair and replacement processes, some linked to the cell cycle. To be
conservative we consider chronic dose rates in mGy per month. Only for
irreparable damage would mGy per life be appropriate, and only by
examining data can it be discovered whether this is applicable to any extent.
What is the effect of a chronic radiation dose rate? Where does evidence to
answer this question come from? The biological response to a radiation dose
is the subject of Chapter 8, but it is good scientific practice to let the evidence
speak for itself before interpreting it in one way or another.
Experimental data on mice, dogs and humans
We start with the effect of beta and gamma radiation [19]. (The effect of alpha
radiation is somewhat different and will be described at the end of this
chapter.) Large-scale radiation experiments on humans, even under controlled
140 Chapter 6: Effect of Large Radiation Doses
conditions, are frowned upon because they are thought to be dangerous.
Instead we have to rely, either on experiments with animals, or on the best
human information that is available, by chance or accident. In controlled
experiments on animals their number can be large depending on the resources
available. Observations may be compared in detail with a control group
which is identical in all respects, except that its members did not receive the
radiation dose. Results from a relevant experiment were published as early as
1915 and 1920, and are described in Chapter 8. Today genetic variation can
be removed as a possible source of confounding by employing a single
genetic strain of mice for both the irradiated and the control group. However,
mice differ from humans, and dogs are different again. Conclusions found in
mice or dog experiments cannot be related directly to humans, most
obviously because their life spans and metabolic rates are different. So results
can only be indicative, although, for acute experiments at least, the agreement
may be fair.
But it is in the effect of chronic doses that such experiments are most useful,
for instance to show the different sensitivity of adults and juveniles or
foetuses. Some authorities suggest that sensitivity to radiation decreases with
age, but others point out that youth is less sensitive, thanks to a more
effective immune system. When tested in experiments on mice these
questions can be answered quickly and also combined with post-mortem
examination. The short lifespan of mice limits the useful information that
such data can give for any prolonged exposure. A better choice is the study of
beagles with a natural lifespan of 12 to 15 years. In such studies with various
lifelong dose-rates, lifespans and causes of death can be compared with those
of a control group who were not irradiated. These data do show significant
effects from chronic radiation, but only at high dose rates together with high
lifelong doses. The details will be seen in Chapter 8. It is still relevant to
ensure that the most significant human data tell a consistent story.
Cancer caused by radiotherapy for an earlier cancer
The task is to track down evidence for human cancer – carcinogenesis, if you
prefer the long name – due to chronic or protracted radiation. This turns out
to be surprisingly difficult, in large part because chronic radiation simply
does not cause cancer at low and intermediate dose rates as readily as might
be expected. What happens at high dose rates, such as used in the medical
treatment of cancer? This radiotherapy is given as a course lasting six weeks
or so; each day a fraction of the radiation dose is given. This protracted dose
is better seen as a chronic rather than as an acute dose, because a day is long
enough for the irradiated tissue and its cells to react to the radiation, as
confirmed in laboratory test-tube experiments. In practice this fractionation
of the treatment turns out to be essential to its success [20].
Nuclear is for Life. A Cultural Revolution 141
The point is that, although this very large dose, given every day, may kill the
cells of the tumour as intended, it may also itself be a source of new
carcinogenesis in the healthy tissue close by. Examined in this way, data on
the vast clinical experience of radiotherapy can come close to answering the
question of a threshold,
What is the lowest chronic radiation dose rate that is found to give
rise to cancer?
There are many details that make a quantitative conclusion difficult.
Nevertheless, members of the public undergoing a course of treatment
receive up to 1,000 mGy per day to healthy tissue which then recovers. This
amounts to a very large total dose over a period of a month or so, and they
thank the radiologists for this treatment that is given to kill their cancer, or at
least provide palliative relief. As we shall see in Chapters 8 and 9, the chance
that the radiation causes a new primary cancer is something like 5%. If it
were much higher, the clinicians would scale back the daily dose; if it were
much lower, they would increase the dose to be more certain of curing the
initial cancer.
Indeed, everybody knows a friend or relative who has experienced such a
course of radiotherapy treatment with this sequence of high doses. These data
do not come from experiments in a concrete bunker hidden away at a secret
research laboratory that might be thought unfriendly or untrustworthy. On the
contrary, the public have every reason to accept and acknowledge such
information. They should realise where it comes from. A discussion of the
doses used is openly available on the website of the Royal College of
Radiologists [20].
Living with artificial radioactivity
Are there no data for humans exposed to a constant radiation dose-rate lasting
many years? Sources of such data are unusual, even for moderate rates, but
they do exist and there is one in particular. In 1982 a development of 1,700
apartments was built for 10,000 residents in Taiwan. The structural steel used
was contaminated by cobalt-60 – it must have included scrap structural steel
from a fission reactor. This isotope is formed when natural cobalt-59 in
structural steel absorbs an extra neutron. Such neutrons do not exist in the
wild, because left on their own all neutrons decay with a half-life of 10
minutes. The only place where cobalt-59 might meet a free neutron is inside
the vessel of a working fission reactor. Anyway, what were the consequences
of the accident?
Cobalt-60 has a half-life of 5.3 years and decays with the emission of a 1.3
MeV gamma; such radiation is very penetrating. In the Taiwan apartments it
irradiated the occupants continuously over a period up to 20 years without
their knowledge. By the time this was discovered 1,100 people had received
142 Chapter 6: Effect of Large Radiation Doses
an annual dose of more than 15 mGy; 900 had received between 5 and 15
mGy annually. The residents were quite unaware of their exposure and there
seems to be general agreement that the data show no evidence for excess
cancer or any other ill effect [21]. The data have been examined for beneficial
effects of low dose rate radiation, but 15 mGy per year is too low a dose rate
for any significant conclusion to be drawn. Data for larger chronic dose rates
would be needed to show firm evidence of an effect although claims are
made.
Living with natural radioactivity
A source of chronic radiation that is occasionally much larger than 15 mGy
per year is the ever-present natural background radiation that varies
considerably, depending in particular on the local geology and height above
sea level (discussed in Chapter 5). The geological dependence comes from
local variations in naturally-occurring potassium, uranium and thorium ores.
Alpha radiation is absorbed within the minerals, but the gamma escapes to
contribute to the environmental background. Radon, the naturally occurring
radioactive gas, contributes by escaping too.
Radon-222 was discovered by the German chemist, Frederick Dorner, in
1900. It is a noble gas with complete electron shells and little interest in
chemical combination – in fact it is the heaviest in the sequence of such
gases that starts from helium and runs through argon to xenon, and finally
radon. It is produced in the alpha decay of radium-226 which is a member
of the decay sequence that starts from uranium-238. The concentration of
uranium in the Earth's crust is very variable, and so that of radium is too.
Radium-226 has a long half life, but is relatively soluble in water. So
when it decays to radon-222, it may already be dissolved; this is
significant for the half life of radon-222 is only 3.8 days. (If still in the
rock, it would escape into the air much less frequently.) Each atom of
radon has a mass 222, eight times heavier than a nitrogen molecule in air,
and so the gas naturally accumulates at low level, particularly in mines,
cellars and caves.
Exposure to radon may depend on location within a house, how the house is
built and the way it is occupied and ventilated. As a gas and alpha-emitter,
radon is expected to cause lung cancer. The picture is one in which radon is
inhaled from the surrounding air and some atoms decay before it is exhaled
again. The products of decay are not gases, and these products themselves
decay in a number of sequential alpha and beta emissions that add further
dose to the lungs (see Table 2 in Chapter 5).
Because radon is a colourless and odourless gas present in the home, it can
Nuclear is for Life. A Cultural Revolution 143
haunt the imagination of the worried well, just as effectively as any tale of
germs round the bend. Many home owners are persuaded to pay for radon
remediation, and a radon survey may be recommended by their agent when
they sell their property [22]. Such attention to domestic radon has become a
profitable industry in affluent countries, bolstered by regulations not
amenable to public scrutiny. The concentration of radon in the air is measured
in Bq per cubic metre. The Action Level recommended in the UK is 200 Bq
m-3 with a Target Level set at 100 Bq m-3. These may look reasonable
numbers, but the actual radon concentration at this Target Level is truly
minute. Even if radon did have an odour or was coloured, it would not be
detectable because its proportion at this level is only 1 part in 6×1017.
We can calculate the radon concentration for an activity of 1 Bq per m3
= 474,000 (secs, mean life radon-222) / 2.68×1025 (total molecules per m3)
= 1.768×10-20 radon molecules per air molecule.
At the Target Level the concentration is 100 times larger than that. That is
less than 2 parts in 1018, a million times a million times a million - that is
not very much!
What radiation dose is received by inhaling air containing 1 Bq m-3 radon?
Estimates vary within a factor ten. The ICRP says that it gives 0.017 mSv per
year [23 p 16]. UNSCEAR says it is equivalent to 9 nSv per hour, or 0.079
mSv per year [24]. Being conservative and taking the UNSCEAR value, the
dose to someone living 24/7 in an environment at the Action Level would be
16 mSv per year, less than 2 CT scans. That should be of no consequence, but
what do the data say is the effect on the lungs of this modest dose rate?
There is no shortage of academic studies that cast doubt on any link between
domestic radon and lung cancer [25, 26, 27, 28] and, equally, a number of studies
[29, 30, 31] that, by relying on a curious derivative of the LNT model, keep the
radon safety industry and the radon mitigation services in business. So should
householders worry about domestic radon? The basic question is whether
there is a significant measured correlation between the radon environment
and the incidence of lung cancer. The published answers to this question are
quite unsatisfactory and such a correlation is not established. One may draw
the conclusion that spreading concern about natural concentrations of radon
deceives the public and that any related remedial work is wasteful,
unnecessary and should be discontinued. There are technical but critical
points to summarise and we put them in a box so that readers can skip over
them if they wish.
144 Chapter 6: Effect of Large Radiation Doses
This is a brief summary of comments on the case made by those who
report a correlation between domestic radon and lung cancer:
1. The effect of radon must be small because the initial local
national analyses reported no statistically significant influence.
The large continent-wide meta-analyses [29, 30, 31] make identical
heavily loaded assumptions in order to show that environmental
radon causes lung cancer, a result that they claim to be
significant. Because of these contested assumptions the three
claims are not independent.
2. The claimed linearity would mean that each cause and its effect is
separate from every other cause and its effect. The science behind
this was discussed in Chapters 4 and 5, and also in Radiation and
Reason, Chapter 7. In other words, if the dependence of the
cancer risk (R) on radon concentration (r) and smoking (s) were
linear, R would be
R = A*s + B*r + C
with A, B and C being constants. C is a background. But the data
say that this is not true for the carcinogenic effect of radon and of
smoking.
3. The authors of [29, 30, 31] use a non-linear formula for R of the
form (with C, D and E constants)
R = (C + D*s) * (1 + E*r).
Significantly in their formula the dependence of R on radon r also
involves smoking s which makes it non-linear. They call this the
Relative Risk model. In fact, since smoking increases R by a
factor 25 according to them, their analysis forces a radon
dependence which is 25 times larger for smokers than non-
smokers. They offer no justification for this blatantly non-linear
assumption, except to mis-represent it as being linear.
4All available data in the literature on cancer induced by radon
have been re-analysed recently by Fornalski and Dobrzynski [27]
using a full range of possible hypotheses. These include constant
risk, linear risk and relative risk as applied by the 3 meta-analyses
(so called LNT). If this model is forced, their analysis agrees with
the results found by the proponents.
However, having compared the likelihood of the different models
quantitatively all 28 sets of available data, Fornalski and Dobrzynski
conclude [27]
a Bayesian analysis shows that the radon data published in 28
analyzed studies bear no evidence of the dependence of lung .....
Nuclear is for Life. A Cultural Revolution 145
In summary, find that betting odds of 90-to-1 in favour of no dependence of
lung cancer on radon against the standard safety story. An example of a study
that did not assume the relative risk model is the analysis of cancer data on
non-smoking women in former East Germany [26]. In the south east region
the radon concentration is high, but the data (up to 1,000 Bq per m3) show no
indication of any increase in cancer, in disagreement with the general meta-
analyses.
Meanwhile there is an extensive tourist industry based on spas that boast of
hot radioactive waters that are claimed to provide therapeutic benefits [32].
They may well do so, and at the very least are popular with customers. The
water is warmed by geothermal heat, that is fired by the radioactivity that
makes the centre of the Earth hot and provides the energy for all volcanic
activity and earthquakes. Not surprisingly many such facilities lie at the
boundaries of tectonic plates, including Iceland, California and Japan. These
therapeutic centres have a strong tradition in Germany which like Japan is a
notably radio-phobic country.
The conclusion should be drawn that this radioactivity, either in background
radiation or in health spas, certainly does no major harm, although it is not
intense enough to show the threshold at which damage to health begins. We
should continue our search for evidence of the effect of more intense chronic
radiation. And cancel that expensive contract for radon remediation on the
house too.
Effect of intense chronic alpha radiation
The life of Marie Curie
For Marie Curie, working with alpha decay was an integral part of
disentangling the elements produced in the natural radioactive decay of
thorium and uranium. This was a matter of chemistry, as well as physics, and
it was through their chemistry that she was able to identify them. Clearly, she
was exposed to beta and gamma as well as alpha radiation throughout her
career, but nobody has even guessed what dose she must have received. One
may speculate that she adapted to radiation as she lived to 66, not far short of
cancer incidence on the dose in the analyzed dose range. It
follows from the model selection routine that in order to accept
the linear no-threshold (LNT) dose-effect relationship preferred
by many researchers, one should a priori have an over 90 times
higher degree-of-belief in such a relationship than in a dose-
independent model. [27]
146 Chapter 6: Effect of Large Radiation Doses
the average life span at that time, showing that her life was not drastically
foreshortened by her radiation work. Her husband, with whom she shared her
first Nobel Prize, died at age 46 in a horse-drawn road traffic accident in
Paris, vividly showing how life depends on chance, but her achievements did
not.
Because alpha radiation has a very short range, the dose that it gives is
confined to a region very close to the source, and that makes the dose harder
to measure than that from beta or gamma radiation, both of which spread out.
Alpha radiation is high LET, so it is intense (in joules per kg) and gives more
biological damage per joule than beta or gamma radiation by a weighting
factor. This factor is the cause of some mumbo-jumbo in the LNT model, as
described briefly in Chapter 5. For alpha radiation the factor is taken to be 20.
We ignore this and look for a threshold in mGy per month. Any threshold
found for permanent damage by alpha radiation is then an extremely
conservative estimate of any threshold for low-LET radiation. This is the
strategy we follow.
The Radium Dial Painters and litigation
Practical radiation safety, like safety in other activities, is largely a matter of
education, training and overcoming ignorance. A historical instance is the
story of the Radium Dial Painters. These were mostly young girls who were
employed to paint the faces of watches and instruments with luminous paint
early in the twentieth century. The paint contained radium whose radioactive
decay provided the energy for it to glow in the dark. Painting the fine lines,
numerals and dots was exacting work, and the best workers licked their
brushes to keep a fine point. The industry intensified in the First World War,
but it was not until 1926 that it was shown that the technique of licking
caused bone cancer and the practice was stopped [33]. This action was
immediately effective as will be apparent from Illustration 27.
Radium has a chemistry like calcium, and once in the body, it finds its way to
tooth and bone where it stays for a long time. Radium-226, the isotope
concerned, has a half life of 1,200 years, so providing a chronic source of
alpha radiation for the remainder of the person's life. The radiation has a very
short range and the damage it causes is to the bone. Bone cancer has various
forms, but is relatively unusual and no statistical expertise is needed to
appreciate its effect. Illustration 27 is a plot where each symbol represents the
death of a worker, with the distance across the plot showing the date at which
she started in the industry and the distance up the plot showing her whole-
body radioactivity count rate in becquerel (on a logarithmic scale). There are
two kinds of symbol: '+' for those who died of bone cancer and 'o' for all of
the others. Note that there is no case of death from bone cancer among those
who started after 1926 (the vertical line) and none either with a whole-body
Nuclear is for Life. A Cultural Revolution 147
count rate below 3.7 MBq (the horizontal line). In total numbers there were
1,339 painters with count rates below 3.7 Mbq (and no cancers); out of 191
painters with more than 3.7 MBq, there were 46 deaths from bone cancer.
The plot shows a clear threshold for cancer at about 3.7 MBq, whole-body
alpha radioactivity. Another message was also clear: there is a need for safety
standards and for the public education that should go with them. With these
in place from 1926, safety was assured.
However the incident had mixed consequences and casts a long shadow
down the history of radiation safety [34]. The new safety regime was
introduced following denial by management and litigation by workers. This
Illustration 27: Data for the deaths of Radium Dial painters and
whether they died from bone cancers (+) and otherwise (o), according
to radioactivity intake and year of entry. Horizontal dashed line is
activity threshold for bone cancer 3.7 MBq.
148 Chapter 6: Effect of Large Radiation Doses
engendered a spirit of fear and distrust of nuclear radiation for the first time.
In fact the law is a totally unsuitable instrument that turns science into a set
of instructions to be obeyed, instead of guidance to be understood. In the
history of radiation the case of the Radium Girls has resulted in safety
advisors putting the need for education second to the need for precautionary
measures, even where these are unnecessary. For many organisations since
that time, safety has become more a matter of protecting those responsible
from litigation, than protecting employees from injury. On the employee side,
unknown science became distrusted by default, whereas collaboration and
education should have been demanded instead.
On the positive side the incident demonstrates evidence for the existence of a
threshold. No statistical gesticulations are needed to see the result, although
the processes of litigation ensured that for many years the data in Illustration
27 were not freely available. The threshold in whole-body radioactivity of 3.7
MBq was established in 1941 by US National Bureau of Standards [35]. A
practical threshold for a lifelong chronic dose was established by Robley
Evans at 10 Gy [33], that is in the region of 1,000 mGy per year [36].
How does this observed threshold for radium compare with the non-
observance of cancer at Goiania below 100 MBq for caesium-137? The
energy of each radium decay is six times that of caesium (see Table 2 in
Chapter 5). So the Dial Painter threshold would be compatible with a cancer
threshold of 20 MBq or higher for a whole-of-life caesium-137 exposure. At
Goiania no cancers were seen for 100 day exposure to 100 MBq and more.
We may not conclude very much except that the data are not in obvious
conflict. This seems a rather empty statement, but it matters, because in both
cases the exposures are very large relative to the usual safety prescription. In
Chapter 9 we will pick these numbers up again, checking them against other
sources to arrive at a sensible and consistent conservative safety bound for
chronic radiation of all types.
Safety of plutonium as a new element
The nuclear bomb dropped on Nagasaki in 1945 used plutonium-239, rather
than uranium-235, the nuclear explosive used at Hiroshima. Plutonium is an
artificial element that only existed in microgram quantities until mass
produced by the first nuclear reactors after December 1942. Plutonium-239
decays by alpha emission with a half life of 24,100 years, and its rate of
fission is smaller than its alpha rate by a factor of 4.4×10-12. So in effect it
does not fission at all, except when artificially stimulated by neutrons. This
shows that plutonium-239 is a rather innocuous material, in spite of the
character given to it in horror movies. In fact, the reason it acquired a dubious
reputation in the early days was rather circumstantial.
After the unpleasant surprise of the carcinogenic effect of radium, as exposed
Nuclear is for Life. A Cultural Revolution 149
by the Dial Painters, the safety environment for any new unknown alpha
emitters was precautionary and suspicious. Nobody wanted to get caught out
twice, especially given the possibility of being faced by a clutch of ambitious
but un-scientific lawyers.
To set up a sound safety regime for the new element would have required a
supply of plutonium and sufficient time in which to conduct tests: for even
with animals such experiments take time. But the quantity of plutonium
needed and the time scale on which it had to be manufactured and machined,
always with the necessary safety in place, was extraordinary. To make a
critical mass (several kgs by 1945) the quantities had to be scaled up 1,000
million-fold from the microgramme quantities initially available in 1942
when safety procedures had first to be considered. Such a scale-up for an
unknown material would alarm any responsible safety authority!
Nevertheless, safe working practices had to be decided, rapidly and in secret.
Experiments with animals were rushed and did not always give consistent
results [37]. The uncertainty made some experiments with humans essential.
These were carried out necessarily in secret, and without the knowledge of
those treated; this deception added to the public distrust, when in later years it
was revealed what had been done.
The uncertain conclusions of the tests, the secrecy, the pressure and the
obvious lack of confidence at that time led, all too easily, to extra-cautious
safety regulations, the antithesis of Marie Curie's advice, Nothing in life is to
be feared. It is to be understood. Unfortunately, however, the legacy of
distrust has never been reversed, and the reputation of plutonium has never
been rewritten, as it should have been. Hollywood and the media have been
happy to maintain its reputation as the most dangerous element on Earth, an
accolade better deserved by oxygen.
It was established that plutonium is not retained in the body as effectively as
radium and, although both elements are found in bones and teeth, plutonium
does not penetrate into bone to the same extent as radium. Under the
manufacturing conditions of the Manhattan Project, inhalation of plutonium
dust caused most concern at the time. But the medical records of all those
Los Alamos workers with lung activity greater then 52 Bq showed no
negative effect that could be attributed to plutonium when analysed 42 years
later in 1991 [38]. Lung activities in 1987 (or at death) ranged to 3,180 Bq
with a median value of 500 Bq. The highest activity is compared with the
threshold found for the Radium Dial Painters in Table 6.
150 Chapter 6: Effect of Large Radiation Doses
Isotope Activity Bq per kg Notes
Radium Dial Painters radium-226 53,000 (absorbed) 3.7 MBq body.
Cancer threshold
Los Alamos worker,
highest after 42 years
plutonium-
239
4,540 (absorbed) 3,180 Bq in lung
mass ~ 0.7 kg
Radon, 100 Bq / m3
(or 4 pCi per litre)
radon-222 ~100 (in air) supposedly safe
limit
Alexander Litvinenko,
assassinated 2006
polonium-
210
10-40 million
(absorbed)
1,000-3,000 MBq
body. Fatal [39]
Harold McCluskey,
worker accident 1976
americium-
241
0.5 million
(absorbed)
37 MBq body. No
cancer in 11 years
Table 6: A comparison of human cases involving high internal
activities of various different alpha emitters.
Evidently, even the highest level of plutonium activity is substantially less
than the threshold for cancer among the Radium Dial Painters. Such a
comparison would be ill-advised if the difference were small, but that is not
the case. The worst fears of those charged with the safety of plutonium
workers in the 1940s were not realised in practice. Nevertheless the
reputation of plutonium as the most dangerous substance known to man has
never been corrected in the popular mind.
Extreme experiences, Litvinenko and McCluskey
Malicious intent is dangerous, whatever technology is used. The poisoning of
the Russian agent, Alexander Litvinenko, in London in November 2006
would have been no less fatal if he had been assassinated by Lucrezia Borgia
(1480-1519) with arsenic, administered in a glass of wine. The massive dose
of polonium-210 that he was given in a cup of tea, once ingested, could not
be treated, although as an alpha emitter the radiation was not dangerous to
others. He died after three weeks.
Single cases should be seen only as qualitatively interesting, but the story of
Harold McCluskey is at least a happier one. At the Hanford Plutonium
Finishing Plant in 1976 he was working through a glove box behind a lead-
glass screen. When there was an explosion he received an intake of at least 37
MBq of Americium-241, 500 times the occupational limit. Americium-241 is
an alpha emitter used in a small quantity in domestic smoke alarms; it is a
component of nuclear waste. McCluskey survived for another 11 years after
the accident, eventually dying from coronary artery disease. A post mortem
examination is reported to have revealed no signs of cancer in his body .His
Nuclear is for Life. A Cultural Revolution 151
activity was a factor ten greater than the threshold seen for the Radium Dial
Painters, although an examination of Illustration 27 suggests that painters
who had an activity similar to his had a 50% chance of dying of cancer. He
was fortunate. He died aged 75, continuing to the end to be a vocal supporter
of nuclear power.
Uranium – natural, enriched and depleted
Like plutonium, uranium is a typical alpha emitter and it does not fission or
release much energy. It only comes into its own and starts fissioning when
stimulated by free neutrons – and they are not around except inside a working
reactor, or a detonating weapon. Consequently it is remarkably safe and easy
to handle. Its most obvious property is its density, 19.1 times that of water,
and that, with its hardness and high melting point, is the reason for its use in
conventional armaments.
Natural uranium is 99.3% uranium-238 (with a half-life of 14.1 billion years)
and 0.7% uranium-235 (with a half-life of 0.7 billion years) with trace
amounts of uranium-234. Uranium, enriched as a reactor fuel, has a few
percent of uranium-235, but handling it is not hazardous. Only when
quantities begin to approach the critical conditions of geometry and
enrichment does the neutron flux begin to multiply. Otherwise, uranium is a
fairly safe material.
Depleted uranium is even safer, the percentage of uranium-235 having been
lowered – hence the description depleted. Its lack of risk is the subject of two
reports by the Royal Society [40, 41].
Notes on Chapter 6
1) Health Effects of the Chernobyl Accident, WHO (2006)
http://whqlibdoc.who.int/publications/2006/9241594179_eng.pdf
2) The Radiological Accident in Goiania, IAEA (1988)
http://www-pub.iaea.org/mtcd/publications/pdf/pub815_web.pdf
3) Dosimetric ... radiological accident in Goiânia in 1987, IAEA (1998)
http://www-pub.iaea.org/MTCD/publications/PDF/te_1009_prn.pdf
4) Protracted irradiation ... in the Goiânia accident. NJ Valverde Brit J Radiol suppl
26: 63-70 (2002)
5) NJ Valverde (2013) private communication
6) Internal radiocesium contamination of adults and children in Fukushima
measurements. Hayano RS, et al. Proc. Jpn. Acad., Ser B 89 (2013).
https://www.jstage.jst.go.jp/article/pjab/89/4/89_PJA8904B-01/_pdf
7) The banana equivalent dose Wikipedia
http://en.wikipedia.org/wiki/Banana_equivalent_dose
152 Chapter 6: Effect of Large Radiation Doses
8) http://link.springer.com/article/10.1007/s00411-010-0267-3#page-1 One of
several papers from this group. See also
http://www.measuringbehavior.org/files/2012/ProceedingsPDF%28website
%29/Posters/Lafuente_et_al_MB2012.pdf
9) These may be seen at http://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?
dbs+hsdb:@term+@DOCNO+7389
10) Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man.
Geneva: IARC WHO,. V78 478 (2001) http://monographs.iarc.fr/ENG/
Mono graphs page 478
11) http://www.washingtonpost.com/opinions/time-to-better-secure-radioactive-
materials/2012/03/23/gIQAn5deaS_story.html
12) Various references including http://en.wikipedia.org/wiki/List_of_accidents_and
_disasters _by_death_toll#Industrial_disasters
13) Health Effects of the Chernobyl Accident, WHO (2006)
http://whqlibdoc.who.int/publications/2006/9241594179_eng.pdf
14) New Report ... on Chernobyl, UNSCEAR (28 Feb 2011)
http://www.unis.unvienna.org/unis/pressrels/2011/unisinf398.html
15) Papers published by Chernobyl Tissue Bank
http://www.chernobyltissuebank.com/papers.html
16) The international safety authorities have expressed concern at the use of the
English prefix in- which sometimes, but not always, means not, as in inexpensive.
They therefore drop the in- from inflammable and from inheritable too. This text
is not an international safety manual and adheres to traditional English usage.
17) The victims of Chernobyl in Greece: induced abortions after the accident
Trichopoulos D, et al BMJ 1987: 295; 1100.
http://www.bmj.com/content/295/6606/1100.extract
18) UNSCEAR 2008 Annexe D on Chernobyl report
http://www.unscear.org/docs/reports/2008/11-80076_Report_2008_Annex_D.pdf
19) Called Low LET radiation its effect is sparse and spread out. Alpha radiation is
called High LET and is locally concentrated at the microscopic scale.
20) Radiotherapy Dose-Fractionation Royal College of Radiologists (2006)
http://rcr.ac.uk/docs/oncology/pdf/Dose-Fractionation_Final.pdf
21) Chen et al. 2007. Dose-Response 5:63-75.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2477708/
S-L Hwang et al, International J. of Radiation Biology 82 (2006), 849-58
http://www.ncbi.nlm.nih.gov/pubmed/17178625
22) Advice given to house owners by Public Health England
http://www.ukradon.org/information/housesales
23) Report 103: Recommendations International Commission for Radiological
Protection. ICRP 2007 http://www.icrp.org
24) UNSCEAR 2006, Annex E, page 220
http://www.unscear.org/unscear/en/publications/2006_2.html
25) Cohen B L Test of the linear-no threshold theory of radiation carcinogenesis for
inhaled radon decay products (2005)
http://www.ncbi.nlm.nih.gov/pubmed/7814250
Nuclear is for Life. A Cultural Revolution 153
26) Becker K Health Effects of High radon Environments in Central Europe: Another
Test for the LNT Hypothesis? (2003)
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2651614/
27) Pooled Bayesian Analysis of Twenty Eight Studies on radon Induced Lung
Cancers. Fornalski and Dobrzynski, Health Physics 10; 265-273 (2011)
http://journals.lww.com/health-
physics/Abstract/2011/09000/Pooled_Bayesian_Analysis_of_Twenty_Eight_Stud
ies.6.aspx
28) Radon risk and Cancer C P Connell, Forensic Technologies Inc
http://forensic-applications.com/radon/reviews.html
29) Radon in homes and risk of lung cancer: collaborative analysis of individual
data from 13 European case-control studies. Darby S et al. BMJ 2005; 330:223
http://www.bmj.com/cgi/content/full/330/7485/223
30) Adjusting Lung Cancer Risks for Temporal and Spatial Variations in Radon
Concentration in Dwellings in Gansu Province, China. Lubin JH et al. 2005;
Radiat. Res.; 163:571 http://www.jstor.org/pss/3581380
31) Residential radon and Risk of Lung Cancer: A Combined Analysis of 7 North
American Case-Control Studies. Krewski D et al Epidemiology: 2005; 16:137
http://www.jstor.org/stable/20486020
32) Radon risk in spas? G Koteles
http://www.omfi.hu/cejoem/Volume13/Vol13No1/CE07_1-01.html
33) Radium in Humans, A Review of US Studies. Rowland RE, ANL/ER3 (1994)
http://www.osti.gov/accomplishments/documents/fullText/ACC 0029.pdf
with comment (2004) http://www.rerowland.com/Dial_Painters.pdf
34) http://en.wikipedia.org/wiki/Radium#Luminescent_paint
35) The factor of 37 appears frequently because 37 Bq = 1 nCi. The Curie (Ci) is an
older unit of radioactivity.
36) According to LNT using the prescribed weighting factor w=20 for alpha
radiation, the dose 10 Gy would be 200 Sv, that is 200,000 mSv.
37) The Human Plutonium Injection Experiments Moss W and Eckhardt R. (1995)
http://www.fas.org/sgp/othergov/doe/lanl/pubs/00326640.pdf .
38) A 42-y Medical Follow-up of Manhattan Project Plutonium Workers Health
Physics Voelz GL et al. (1991) http://journals.lww.com/health-physics/Ab
stract/1991/08000/A_42_y_Medical_Follow_up_of_Manhattan_Project.1.aspx
39) Polonium-210 as a poison Harrison J, J Radiol Prot. (2007).
http://www.ncbi.nlm.nih.gov/pubmed/17341802
40) https://royalsociety.org/policy/publications/2001/health-uranium-munitions-i/
41) https://royalsociety.org/policy/publications/2002/health-uranium-munitions-ii/
Nuclear is for Life. A Cultural Revolution 155
Chapter 7: Protected by Physical Science
In the beginning the universe was created. This has made a lot of
people very angry and has been widely regarded as a bad move.
Douglas Adams (1952 – 2001)
Nucleus at the centre of the atom
Physical science and quantum mechanics 156
The cast – proton, neutron and electron 157
Atomic structure of matter 157
Nuclear sizes and energies 160
Energy in physical science
Conservation of energy 161
Kinetic energy – the energy of motion 162
Thermal energy 162
Directional energy 163
Energy density 164
Natural apprehension 165
Nuclei inviolate
Isolation by the coulomb barrier 165
Nuclei protected from alpha, beta and gamma radiation 166
Radioactive power in nature
Components of background radiation 167
Radiation history of the Earth 168
Power for plate tectonics 169
Darwin and the 1835 Chilean Earthquake 170
Social reaction to a natural disaster 171
Physical security of nuclear energy
The neutron, unique key to the nuclear energy lock 172
Inherent physical safety 173
Waste from an ancient reactor 174
Notes on Chapter 7 175
156 Chapter 7: Protected by Physical Science
Nucleus at the centre of the atom
Physical science and quantum mechanics
Unlike biological science, which relates to life on Earth, physical science
applies everywhere in the universe and at all times. We know this because
when new instruments allow us to look in more remote places or reconstruct
what happened at earlier times, science finds that the same laws at work as
apply here and now. Of course it is the ambition of every young red-blooded
scientist to find conditions where predictions based on current knowledge
fail. Science aims not to defend its current ideas against attack, as its
detractors sometimes suppose, but to mount such attacks itself. A lack of
success in this object represents a triumph for the state of the science. The
way in which the laws of physics are used to make predictions is what
scientists call theory, a description that can give rise to some popular
misunderstanding. There is nothing iffy about theory. At the end of the
nineteenth century, classical physics, the theory that had been built up on the
foundations laid by Galileo and Newton, was found to give wrong
predictions, but in the early decades of the twentieth century the laws of
quantum mechanics were established, culminating in the work of Paul Dirac,
one of the most brilliant physicists of all time [1]. Today quantum theory or
quantum mechanics – we use the descriptions interchangeably – appears
quite secure in spite of its counter-intuitive results. Some of these are
important, even for a brief understanding of the atom and its nucleus.
Here is an everyday example of the strange ways of quantum mechanics.
When an electric current passes along a wire, electrons (which are particles
of ordinary matter) travel through solid copper with only the smallest
hindrance. This is incomprehensible to common sense and to classical
physics too, but is quite normal in quantum mechanics. It is not really weird
because it happens every time we turn on an electric light! It is the real world
and we should take it on board.
In the 1920s some of the more wacky consequences of quantum theory were
thought to be quite beyond the reach of actual experiment, but the scientific
papers of the day described what should happen in these experiments if you
ever could do them – they were called Gedanken or thought experiments.
Physicists in those days were wrong to think that these would be forever
impossible to do, and recently such experiments have been carried out and
have shown that the theory was correct in its predictions. So there is every
reason to be confident in the current theory of the physical world, which
means that it can be used productively for the benefit of society, knowing that
it is unlikely to fail. In practical applications, it is normal to use a common
sense or classical picture of physical science (even though it is technically
wrong), referring to quantum theory only where it has something important
Nuclear is for Life. A Cultural Revolution 157
and significantly different to say – and that is the case for the simplified
descriptions in this book, usually classical, but sometimes quantum. So what
are the elements of physical science and how do they behave?
The cast – proton, neutron and electron
The theory is like a play with a cast of characters and a script or plot for how
they interact or relate as the story develops. Here is a simplified summary –
correct but omitting some characters that do not come into our story of
everyday energy and the environment. (These extra characters are well
known and have been studied carefully at laboratories like CERN, Geneva.)
The cast consists of a colossal number of particles, of which there are only
three different kinds: the proton, the neutron and the electron. Every electron
has the same negative electric charge, rotates on its axis (spin), has a mass of
9.1×10-31 kg, and behaves as a point in space. It is a principle of quantum
mechanics that all electrons are completely indistinguishable from one
another. The proton and neutron have positive and neutral electric charge
respectively, also rotate, but are some 2,000 times heavier than the electron.
The script tells us that, electrically, the electrons and protons attract one
another, but that electrons mutually push one another apart with an inverse
square law; and any number of protons do likewise. Neutrons, being neutral,
are uninfluenced by the electric charge of electrons and protons. But there is
another force called the strong force that acts between neutrons and protons
when they are very close [2]. If protons and neutrons are further than a few
times 10-15 metres apart, the strong force is absent – this distance is 100,000
times smaller than an atom. Just as the neutron is oblivious of the electric
force, so the electron is oblivious of the strong force. So essentially, electrons
and neutrons never collide – it is as if they can pass right through one
another.
Atomic structure of matter
So how do these simple ingredients with their mutual attractions and
repulsions determine the structure of matter, that is, the aggregation of very
large numbers of electrons, protons and neutrons? There will be much more
to say about energy in the next section, but here we just need the principle
that the most stable structure should be the arrangement of lowest energy.
That is the structure that you get when these electrons, protons and neutrons
just fall in on top of one another, so to speak. The result is many neutral
atoms, each composed of a roughly equal number of electrons and protons
with some neutrons. Within each atom the neutrons and protons fall inwards
to form the very dense nucleus at the centre of each atom. To understand the
details we need to look at how the arrangement of lowest energy comes
about.
158 Chapter 7: Protected by Physical Science
The energy concerned will be made up of simple kinetic energy, ½MV2 for a
mass M with speed V, and the potential energy due to the forces described.
The strong force dominates, so, first of all, the protons and neutrons cling
together under their mutual attraction. This ceases to be effective for very
large numbers of protons and neutrons when the cumulative mutual electrical
repulsion between the protons, with its longer range, becomes larger than the
strong attractive but short range force [3]. This limited composite of protons
and neutrons is the nucleus; all nuclei are about the same size within a factor
5, that is a few times 10-15 metres across. The most stable has about 26
protons and a few more neutrons, but those with up to 90 protons and 150
neutrons are also more or less stable. This is the story behind the nuclear
binding energy curve shown in Illustration 28, where the heaviest and lightest
are the least favoured, energetically. So energy can be released in two
different ways: firstly, if a nucleus with the very largest value of A, the
number of protons and neutrons, could split into smaller ones – this is called
nuclear fission; secondly, if a pair with the very smallest number A can be
combined in some way – this is called nuclear fusion.
That such changes are quite extraordinarily difficult to achieve is closely
related to the inherent natural safety of nuclear energy. The effectiveness of
this security completely overshadows any regulation that might be imposed
by any human safety authority. To see how this happens we need to look
further at the structure of matter on a wider scale.
Because of their large positive charge there is a very strong mutual repulsion
Illustration 28: A graph showing how the nuclear binding energy
depends roughly on A, the number of protons plus neutrons, for the
more stable nuclei.
Nuclear is for Life. A Cultural Revolution 159
between nuclei, and consequently they are pushed to positions at a maximum
distance apart. What sets the scale of this separation and, therefore, the
average density of all normal matter? This is where the electrons play an
essential part. To minimise the overall electrical energy their number equals
the number of protons. So each nucleus is surrounded by enough electrons to
balance the number of its protons, roughly speaking. Indeed the outermost
electron should balance the combined charge of the nucleus and all the other
electrons further in. This is a single question: how does an electron behave
when orbiting around a net equal and opposite charge.
We need quantum mechanics to understand
nature's solution to this question. It is a
matter of the balance between two effects,
the electrical one that pulls the electron and
nucleus together and another force that
pushes them apart – this is where the
quantum wave nature of the electron comes
in. You cannot put a wave into a region that
is smaller than its wavelength – putting it
graphically, the region needs to be at least
one wiggle in size, as sketched in Illustration
29. Since the work of Louis de Broglie in
1923, it has been known that the momentum
of a particle (its mass times velocity) when multiplied by its wavelength is a
constant, known as Planck's constant – and this is precisely true for all
particles at all times. Consequently, it takes kinetic energy, the energy of
motion, to keep a particle in a small region, and the smaller the region the
more energy it requires. By balancing this energy against the electrical
attraction between an electron and a nucleus, the size and energy of an atom
is set. We can calculate this ourselves, as given in the boxed discussion
below. If you prefer, you can skip this and just pick up that the size of every
atom is roughly 10-10 metres across.
Illustration 29: A sketch of a
wave reflecting back and
forth within a box.
Roughly, what is the energy of a mass M held in a box of size X ?
In Newton's mechanics any mass M with speed V has kinetic energy
E = ½MV2, and also a momentum P = MV. This means that E = P2/2M.
In quantum mechanics information about the momentum P is given by a
wave with wavelength λ = h/P where h is Planck's constant, 6.6×10-34 J s.
If the wave describes the position of M, it cannot be kept in a region X
smaller than about half a wavelength, as sketched in Illustration 29.
So h/P ≈ 2X and P ≈ h/2X, where the wavy equal sign means we have
ignored that space is 3D but the result is still approximately correct.
continued on overleaf.
160 Chapter 7: Protected by Physical Science
Notice that if you skipped the calculation in the box, you will have to trust
the result. The only alternatives are to turn your back on the whole business
or to study it yourself. In general these are the three options: trust, ignore and
study. But only the trust and study options lead to better prospects for life.
Nuclear sizes and energies
What happens if a similar argument is applied to the protons and neutrons
inside an atomic nucleus? The nuclear size was measured to be some 10-15
metres in the early twentieth century by means of Rutherford Scattering
experiments. The energy of protons and neutrons inside comes out at about
20 MeV by the same argument as used for the energy of an electron confined
to an atom.
Using this result we can replace P in the formula E = P2/2M
to get E ≈ h2/8MX2.
This is what we wanted to find, a formula for E given the values of M and
X. Now we can put in some numbers and find some answers:
What is the size of an atom, roughly?
For an electron (M = 9.1×10-31 kg) in orbit round a nucleus, this kinetic
energy should about match the electrical potential energy e2/4πε0X in
standard SI units which means X ≈ 4πε0h2/8Me2
So putting in the numbers, the size of the atom is calculated to be about
X = 3×10-10 m across. Actual measured sizes are 2 to 3 times smaller.
What is the energy of an electron in an atom, roughly?
Putting in numbers for an electron in an atom of size X ≈ 3×10-10 m gives
kinetic energy E ≈7×10-19 J, that is 4 eV.
The measured energy of the hydrogen atom, as an example, is 13.8 eV.
These calculations are over-simplified, which is why the answers come
out slightly wrong. Using quantum mechanics to calculate the actual
wave shape in three dimensions, highly accurate energies are derived.
Although the answers then depend on the details, the broad principles are
already here. As a study of chemistry relates, these finer details depend on
the way in which neighbouring atoms share electrons to form molecules,
and a study of condensed matter physics describes how these molecules
or atoms configure themselves in a 3D-crystal, or in a liquid or gas.
However, within a factor ten, all atoms are of similar size, and the
energies of their outer electrons are similar too.
Nuclear is for Life. A Cultural Revolution 161
So there is a factor of a million between the energy of an electron in an atom
and the energy of a proton or neutron in a nucleus, as described by simple
quantum mechanics. Chemical energy, for instance the energy released by
burning carbon fuels, comes from the electrons when atoms are rearranged in
molecules. In a similar way, nuclear energy comes from rearranging protons
and neutrons in nuclei. So this factor is the basic reason why nuclear energy
is about a million times more powerful than carbon fuel combustion. These
simple calculations have extraordinary consequences.
Energy in physical science
Conservation of energy
Energy is a crucial quantity in basic physical science, and hardly less
important in everyday life. One of the underlying laws of science is that
energy is conserved, so energy cannot be made and can only be transformed
from one form to another or moved from one place to another – that is why
conservation is important. So whenever reference is made to saving energy or
generating energy, that can only mean retaining it in a usable form, or
transforming it from a stored to a more readily accessible form.
That is rather an important point. It means that a search for a way to store
energy is just a search for another energy source – a source and a store are
similar. The science that describes what you can do in principle when you
move energy around is called thermodynamics, but we need only its simplest
idea here, that energy is conserved. As a consequence, energy stores are
potentially just as dangerous as energy sources. Consider the energy stored
by a hydroelectric dam. A crack, whether initiated by an earthquake or a
design failure, may be a precursor to the release of a wall of water on those
who live downstream. To avoid this it is necessary to be able to release the
energy stored in the full dam as fast as possible, but without causing loss of
life. So the problem of dispersing stored energy in the event of an accident is
not peculiar to a nuclear reactor with a rapidly rising temperature, like the
ones at Fukushima Daiichi. If a sufficiently large energy store were
developed to accumulate energy from wind or solar, it would have a similar
problem in the event of an accident – even if the principle of making such a
What is the energy of a proton (or neutron) in a nucleus, roughly?
Using the same formula E ≈ h2/8MX2 that we used for an electron in an
atom, we put in the values for a proton mass (M = 1.7×10-27 kg) and a
nucleus of size X ≈ 3×10-15 metres (eg for carbon-12).
The calculation gives a value E ≈ 3×10-12 J, that is 20 MeV.
Actual observed proton and neutron nuclear energies are a few MeV.
162 Chapter 7: Protected by Physical Science
store sufficiently large could be solved. At present there is no such solution,
so the problem of its safety has not arisen yet.
A brief discussion of energy should help us to compare different sources.
Kinetic energy – the energy of motion
Material in motion carries energy in a form called kinetic energy. Examples
are the movement of wind and water, or the rotation of a turbine. It is notable
that the energy of a moving mass increases with the square of its speed, so, as
road safety demonstrations are always keen to point out, a car moving at 40
miles per hour has four times the energy that it has if moving at 20 miles per
hour. This energy also increases with the mass of the moving object.
Thinking about the energy of wind, the mass of air reaching the blades of a
wind turbine each second increases with the wind speed. Therefore, the
energy per second available from a perfect wind turbine increases with the
cube of the speed. So there is a thousand times as much energy available
from a turbine in a wind at 50 miles per hour as at 5 miles per hour. That is a
significant problem for a wind farm that is intended to provide a steady
supply of electricity in variable wind conditions. In high-wind conditions this
energy is liable to damage the turbine, even to destroy it – and therefore
much of the cost of a wind turbine goes into ensuring that it is strong enough
to withstand the highest wind conditions. This can be done but it is
expensive. Wind energy is a poor resource because the mass is low, the wind
speed is not great and is highly variable.
Tidal currents are more predictable and water has a higher density than air,
but the speeds are very low even in the best isolated locations. Wave power
has higher speeds than tidal but all of the unpredictability of wind. The
destructive power of wave energy is legendary, and defence against
exceptional storms is difficult and expensive.
Thermal energy
Higher energy is available when larger masses move at higher speeds, like
the speed of sound. The molecules in a gas move around randomly at such
speeds, which is how they are able to transmit the pressure waves of sound so
fast. These moving molecules in a hot gas or liquid are therefore a good
energy source in principle – and this is what we know as thermal or heat
energy. As this way of introducing it suggests, heat is a very powerful source
compared to wind, although there are problems because the motion is random
in direction. The Second Law of Thermodynamics sets the maximum
efficiency with which such random thermal energy can be converted into a
more useful form like a rotating turbine or an electric current. This efficiency
is seldom good. In a typical oil, gas, coal or nuclear power station this
efficiency may be as low as 30%. That means twice as much energy is going
Nuclear is for Life. A Cultural Revolution 163
to the cooling tower or heating the river as is coming out in the form of
electrical energy.
This is the reason that a fossil fuel plant may generate three times as much
carbon dioxide as you might expect. For instance, power plants may be
described as 3,000 MWth (meaning thermal power) or 1,000 MWe (meaning
electrical power). That difference is large and matters. It means that 2,000
MW of energy has to be discarded and this applies to carbon-burning plants
as much as to nuclear ones. There are processes that can make good use of
discarded heat, such as greenhouses and local combined heat and power
(CHP) schemes.
Here is a rough comparison between wind energy and thermal energy. (This
refers to the energy per kg and so does Table 7. As already pointed out, in
terms of the energy per second, light winds come out even worse in the
comparison because the mass of air, the number of kgs hitting the turbine,
falls as the wind speed drops.)
Directional energy
There are other forms of directional energy such as gravitational energy that
can be converted to electrical energy more efficiently than thermal energy.
Lifting a mass upwards by a distance increases its potential energy and
dropping it turns this extra energy into directional kinetic energy. If a
frictional brake is applied, the energy ends up as thermal energy and the
brake will get hot. Note how kinetic energy can be turned back into
gravitational energy quite easily, but once the energy becomes thermal, it
cannot efficiently revert to potential energy again – this is the influence of the
Second Law of Thermodynamics. Hydro-power is the important example; the
efficiency means that energy can be stored; that is surplus energy can be used
We omit the details here, but this maximum efficiency is given by the
quantity (1-T1/T2) where T1 is the absolute temperature of the exhaust and
T2 is the absolute temperature of the hot source. T1 is never much less than
ambient temperature, 293 K, so that there is great advantage in having T2
as high as possible, whether in a diesel car engine or a nuclear power
station.
The energy of mass M moving at speed V is ½MV2. So air moving at 60
miles an hour, that is 22 ms-1, carries 240 Joules of energy per kg, as wind.
The random motion of the molecules of the same kg at room temperature
is 770 miles an hour, that is 345 ms-1, that is 59,500 Joules as heat energy.
So the energy of wind in each kg, even blowing at 60 mph, is smaller than
its thermal energy by a factor 200.
164 Chapter 7: Protected by Physical Science
to pump water up into a reservoir, and then reconverted back into electricity
at a later time, although the number of sites where this can be done on a
grand scale taking advantage of natural land formation is limited.
Consequently such storage is insufficient to support a whole national energy
policy. The cost is quite high and safety is a concern, as always for energy
storage. Directional chemical energy storage – battery storage in fact – is
another important solution that is useful, but has limited capacity.
Energy density
A useful measure when discussing energy is energy density [see Selected
References on page 279, SR1]. Imagine a waterfall, as an example. You
might get the same flow of energy from a very high waterfall with a trickle of
water passing over it, as you do from a large flow of water passing over a low
waterfall. Nevertheless, the high waterfall provides a more powerful source
of energy that could push back the flow of a low waterfall, as it were. We can
describe this by looking at the energy per kg instead of the total energy. This
energy density is called the potential. Sources of high energy density are
much to be preferred; they are compact, require less mass of fuel and
generate less waste. Table 7 shows the vast difference between the energy
density of different sources, even neglecting the poor efficiency factor of ⅓
for coal and nuclear, both being non directional.
Lead-acid
battery
5 mph
wind
60 mph
wind
100m high
waterfall
Fossil
(coal)
5% enriched
uranium
0.15
million
1.7 240 1000 24
million
4 million
million
Table 7: Energy density for various sources (measured in joules per kg).
Note that the energy density of wind is 144 times larger per kg at 60 mph
than at 5 mph, but the energy per second is another factor 12 times higher
because more kgs hit the turbine in a second at 60 mph.
All forms of energy contribute to the energy E in the equation E = Mc2,
where M is the mass change. In spite of what you may find in popular
accounts, this famous equation has no special relationship to nuclear energy.
For example, the water at the top of a waterfall has slightly more mass than
the same water at the bottom when stationary although the difference is tiny.
Because nuclear energies are large, the mass change is measurable when
some E is extracted. The exchange rate, c2, is an impressive 9×1016 joules per
kg. This is how much energy you would get if all the mass were turned into
energy, but the entries in Table 7 are much smaller. Comparison between the
columns shows what really matters. In particular, the number for uranium is
larger than that for coal by the same factor as 1 hour of work on one hand,
and a lifetime at 60 hours a week on the other [4]. When it comes to the
Nuclear is for Life. A Cultural Revolution 165
amount of waste produced per unit of energy, the mass of waste produced by
nuclear is smaller than that produced by coal by 167,000. This factor is
deduced by taking the numbers from the Table, 4 million million divided by
24 million. If the part-used nuclear fuel is recycled, the situation is even more
beneficial.
Here is a slightly different comparison. A modern Li-ion battery stores as
much as 0.2 kWh of energy in 1 kg of lithium. How does that compare with
the nuclear fission energy stored in 1 kg of thorium, for example? In the
nuclear fission of a nucleus the energy released is about 200 MeV – that is
1/1000 of the total Mc2 of the atom. So there are 9×1013 joules of fission
energy per kg of thorium. That is 2.5×107 kWh per kg, or 100 million times
the energy capacity of the Li-ion battery. That number means there is no
contest between a chemical battery and nuclear energy as a source of
electricity. A battery can just about serve as short-term portable storage, but it
needs to be recharged frequently from a base load power plant.
Natural apprehension
It is natural that without sufficient reassurance large energies cause concern.
Standing at the base of a major hydroelectric dam would generate an
unpleasant frisson of fear for most people. Tanks of volatile inflammable
fossil fuel and stores of chemical explosives are no better. Once ignited, fossil
fuels fires are liable to spread without control, especially when the fire
escapes into the environment. Mankind has had to face up to living with this
risk for many millennia. A question is whether the assurance of safety that
cannot be given convincingly for fire can be given for nuclear energy. Since
the energy density is very much higher, the assurance needs to be that much
more complete.
Surprisingly, this assurance is provided from three separate and independent
sources. Firstly, it comes in principle from physical science, as described in
the remainder of this chapter. Secondly, it comes in principle from biological
science, as described in the next chapter. Finally, it comes in practice from
the experience of seventy years of deployment of nuclear energy with a
safety record that is better than offered by any other energy source.
Nuclei inviolate
Isolation by the coulomb barrier
Although nuclear energy is immensely powerful on paper, it is far safer than
expected. Each nucleus lives an isolated celibate life with its nuclear energy
securely locked and the nucleus of one atom never meets the nucleus of
another. In fact, on Earth only one nucleus in a million has changed at all
166 Chapter 7: Protected by Physical Science
since the Earth was formed more than 4,500 million years ago, and then only
by decay. The laws of physics that describe the unconditional electrical
repulsion between like charges ensures that the nucleus is prevented from
doing anything at all. Apart from being carried about passively at the centre
of its atom, the only activity possible for some nuclei is rotation – and for
more than half of them even that is excluded. (Interestingly, this rotation is
the basis of MRI, more fully described as nuclear magnetic resonance (NMR)
imaging – the adjective nuclear is usually omitted from the name out of a
misguided sensitivity to popular nuclear phobia.) Each nucleus is individually
packaged in its own enveloping electronic atomic cloud, 100,000 times its
size, and held in position by an intense electrical force. This packaging is
extraordinary. It is no wonder that none is ever damaged! One can only
marvel at the degree to which nuclei are isolated from one another.
When Rutherford analysed the first experimental data in which two nuclei
(helium and gold) were fired at one another, he was able to show that because
they could bounced off one another at 180 degrees without penetrating one
another, all of their electric charge must be concentrated in a nucleus of tiny
dimensions. The inverse square law means that the electric force increases by
a factor of 1010 in moving close to the nucleus. This electric defence is called
the Coulomb barrier – Coulomb was the pioneer in the unravelling of the
physics of electricity who first described the force between electric charges.
So even the most energetic nuclei can only bounce off one another and do not
have enough energy to penetrate the barrier. In their isolation they are
prevented from releasing their energy under almost any circumstances. Only
at the centre of the Sun at a temperature of some 15 million degrees does a
nucleus get enough energy to meet and react with another, and even there,
only once every few billion years. In the entire life of the Sun such an
encounter will happen just once for each hydrogen atom. That is when it
reacts with another to form helium, releasing the energy that gives us
sunshine and the mainspring of energy for life here on Earth – the details are
more complicated, but the idea is that simple.
Nuclei protected from alpha, beta and gamma
radiation
This isolation of each nucleus from every other is entirely electrical in origin.
But can radiation penetrate this barrier and so react with the nucleus? Alpha
particles and other beams of positively charged particles are repelled by the
positively charged nucleus and cannot reach it at normal energies. This does
not apply to negative and neutral particles, but let's look at each of the
candidates: first, energetic electrons and photons – we come back to beams of
neutrons and what they might do on page 172.
In the environment, electron and photon radiation (beta and gamma) may
Nuclear is for Life. A Cultural Revolution 167
have an energy up to about 2 MeV. Within the target nucleus the neutrons and
protons are tightly bound, and a certain minimum energy is required to
dislodge one. This is analogous to the photoelectric effect in an atom, where a
certain minimum energy is required to dislodge an electron, as mentioned in
Chapter 5. In the nuclear case the minimum energy varies between about 5
and 7 MeV – similar to the energy of nuclear quantum waves worked out
roughly in the box on page 161. As in the photoelectric effect nothing
substantial can happen unless the energy given by the electron or photon to
the nucleus is greater than this value. So in the environment, alpha, beta and
gamma radiation can do no more than just bounce off a nucleus. Only in a
research laboratory can radiation be given enough extra quantum energy to
tweak a target nucleus enough to make a material radioactive.
This is a crucially important result for nuclear safety. It says that nuclear
radiation – that is alpha, beta or gamma – can never make another nucleus
radioactive. That means that radioactivity never spreads from material to
material: it never catches and increases in the way that fire does.
Radioactivity may be carried from place to place, but each individual
radioactive nucleus can decay just once, so as time goes by, the radiation
emitted must die away. This gives nuclear a degree of safety and proliferation
resistance that is qualitatively superior to any fossil fuel hazard. Following
the Fukushima accident nobody seems to have told the families in Japan
about this. They looked on radioactive material as if it was contaminated by a
virus, Ebola for instance. They were frightened of catching its effect, when
there was no reason to be. The difference is simple and it should have been
explained to them that radioactivity is not contagious. That was negligent.
Radioactive power in nature
Components of background radiation
The nuclear security provided by the Coulomb barrier is so good that it was
not until the last years of the nineteenth century that the existence of nuclear
energy was stumbled upon. Nobody guessed the presence of this buried
treasure. Its impenetrable bulwark has provided protection from the
accidental release of this latent energy, ever since it was breached in the
extreme conditions of element-forming nuclear explosions that preceded the
formation of the Earth. Everything on Earth today, except hydrogen, is
actually nuclear waste from that epoch. Since then, thanks to the Coulomb
barrier, activity cooled off rapidly. Most of the unstable nuclei that were left
decayed to stable forms, leaving the particular atoms that we find around us
today. Although that was a long time ago there are a few exceptional isotopes
with such long lifetimes that they are still present and decaying today,
notably uranium-235, uranium-238, thorium-232 and potassium-40. These
168 Chapter 7: Protected by Physical Science
are the sources of the radioactivity that we call natural. In reality there is no
comfort at all to be attached to this not-made-by-man label. Such make-
believe descriptions owe more to man's desire for security than to any
objective science. These primordial radioactive isotopes are scattered
everywhere at low concentrations. Potassium-40, naturally present in all life,
gives most of the internal radiation dose that the human body gives itself, that
is 0.24 mGy per year, discussed in Chapter 5. The radioactive nuclei present
in rocks, soil and water give much of the external dose to the human body
(about 1.2 mGy per year, including gamma rays and radon gas); the rest
comes in the form of medical doses and cosmic rays from space. These rays
produce showers of secondary particles in collisions at the top of the
atmosphere, and some of these reach ground level.
This so-called natural radiation amounts to about 1.0 mGy per year, but
varies a lot according to location. The composition of the local rock and the
radon that it releases is responsible for the wide variation of tens of mGy per
year in places such as Brazil, Cornwall, the Czech Republic, India and
Colorado. Reported doses depend on conditions, for instance whether buried
in the sand, unventilated in a cellar, or taken in the fresh air. Spas which offer
health benefits from radon in their waters are common in these regions, as
well as in Japan, Jamaica and Germany.
Closer proximity to the Earth's magnetic polar regions and greater altitude
increase exposure to cosmic rays because these are less deflected by the
Earth's magnetic field and absorbed by the atmosphere, respectively.
Radiation history of the Earth
After the Earth formed and started to cool, life evolved to be tolerant of the
slowly declining flux of ionising radiation, for if it had not, it would not have
survived. In early times the flux of radiation came, as it does today, both from
local radioactive decay within the rock, soil and water of the Earth and from
radiation reaching the Earth's surface from space. Knowledge of the half-
lives of radioactive isotopes, some still in the Earth's crust today, and a few
others that decayed away in the past 4,500 million years, comes from
laboratory experiments. This enables us to know the activity of the Earth's
crust after the first 1,000 million years, and the dominant change was the
gradual decay of uranium-235 (lifetime 700 million years). The lifetimes of
the other major isotopes, potassium-40 (1,250 million years), thorium-232
(14,100 million years), and uranium-238 (4,500 million years) are
sufficiently long that their activity has not changed much. Neptunium-237 (2
million years) would have died away quite early. It is simple to work out
what the activity was 2,000 million years ago. The answer is that it was just
over twice what it is now. That is not a larger difference than the variation
from one place to another in radiation from rocks today. The big difference
Nuclear is for Life. A Cultural Revolution 169
between then and now would have been in the energy available to drive the
movement of the tectonic plate; this would have been greater by the same
factor two. Earth's volcanic activity must have been that much greater. Even
today, shifts in the Earth's crust have a greater impact on the safety of life
than radiation itself, as was evident in Japan in March 2011.
Today the flux of radiation from space, when filtered by the atmosphere, is
the source of only about 10% of the typical natural dose. The composition of
the atmosphere varied in the past and changes in the ozone layer affect the
flux of UV reaching the surface. In the past it is likely that external events
including stellar outbursts, within and beyond the galaxy, altered the flux of
cosmic rays. These are also influenced by the Earth's magnetic field, and data
show that has changed frequently in the past.
While there were times when the atmosphere was thicker with extra CO2 and
water vapour than today, it is probable that there were other times when the
atmosphere was a less effective radiation shield. Whatever those variations, it
is likely that they were more significant to the viability of life than changes in
the flux of radiation from rocks. Indeed, we are faced by such atmospheric
changes today and the importance of these will continue to dominate the flux
of radiation.
Power for plate tectonics
The main sources of natural radioactivity are listed in Table 8 with their
abundances in the Earth's crust.
potassium-40 thorium-232 uranium-235 uranium-238
Half life 1.27 × 109 yr 14.1 × 109 yr 0.5 × 109 yr 4.5 × 109 yr
Absolute
element
abundance
20,900 ppm 9.6 ppm 2.7ppm 2.7 ppm
Relative
isotopic
abundance
0.01% 100.00% 0.70% 99.30%
Table 8: The main naturally occurring primordial radioactive isotopes
(ppm means parts per million).
The energy that their decay releases is sufficient to maintain the Earth's high
internal temperature, and this generates the slow radial convective circulation
of the Earth's mantle. As a result sections of the Earth's crust that float on top
of the mantle are moved about. These sections are the tectonic plates whose
collision and relative motion are responsible for all volcanic and seismic
activity. So the Japanese earthquake and tsunami of 11 March 2011 were
170 Chapter 7: Protected by Physical Science
caused by the Earth's own natural radioactive decay heat, vastly more
damaging than the effects of the man-made decay heat released by the
Fukushima reactors.
If we look upwards, our view of the universe is almost unobstructed, but if
we look down our ability to see what is happening a few hundred metres into
the Earth is almost non-existent. We do know that the temperature in a deep
mine is elevated and this increase continues towards the centre of the Earth.
The gradient in temperature means that heat is continuously flowing
outwards, by convection and conduction, and has been since the Earth was
formed. The current heat loss is measured as about 44 TW (terawatt),
corresponding to the Earth cooling by about 2 degrees every million years (if
the heat were not replaced). Such a calculation, first carried out by Lord
Kelvin in 1862 without any knowledge of the contribution of radioactivity,
suggested that the Earth should have cooled much more than it has in its 4.5
billion year life.
One large-scale manifestation of the movement of plates on the Earth's
surface is the Ring of Fire [5], a line of volcanoes, trenches and earthquake
locations that stretches in a huge arc around the Pacific Ocean from New
Zealand, crossing the Equator between the islands of Indonesia, north to
Japan, across to Canada, along the San Andreas Fault in California and
southwards along the Chilean coast of South America.
Darwin and the 1835 Chilean Earthquake
Charles Darwin on his voyage aboard HMS Beagle observed the Great
Chilean Earthquake and Tsunami of 1835 that destroyed Concepción and
Talcahuano [6, page164-166]. In his journal for 20 February he wrote:
This day has been memorable in the annals of Valdivia, for the most
severe earthquake experienced by the oldest inhabitant. I happened
to be on shore, and was lying down in the wood to rest myself. It
came on suddenly, and lasted two minutes, but the time appeared
much longer. A bad earthquake at once destroys our oldest
associations: the earth, the very emblem of solidity, has moved
beneath our feet like a thin crust over a fluid;− one second of time
If the internal radioactivity of the Earth produces a steady 44.2 TW
(4.42×1013 watts), to what radioactive energy dose does this correspond?
The mass of the Earth is 5.9×1024 kg, so in a year it receives 0.23 mGy
(that is 2.3×10-4 J per kg). This simple calculation shows that the internal
dose of the Earth is about the same as the internal dose that every human
body receives in a year from his or her own internal radioactivity, in that
case mainly carbon-14 and potassium-40.
Nuclear is for Life. A Cultural Revolution 171
has created in the mind a strange idea of insecurity, which hours of
reflection would not have produced.
And on 4 March he saw the effect of the tsunami created by the earthquake:
We entered the harbour of Concepcion. While the ship was beating
up to the anchorage, I landed on the island of Quiriquina. The
mayor−domo of the estate quickly rode down to tell me the terrible
news of the great earthquake of the 20th: "That not a house in
Concepcion or Talcahuano (the port) was standing; that seventy
villages were destroyed; and that a great wave had almost washed
away the ruins of Talcahuano." Of this latter statement I soon saw
abundant proofs − the whole coast being strewed over with timber
and furniture as if a thousand ships had been wrecked. Besides
chairs, tables, book−shelves, etc., in great numbers, there were
several roofs of cottages, which had been transported almost whole.
His scientific observations are impressive and show profound physical
intuition:
The effect of the vibration on the hard primary slate, which composes
the foundation of the island, was still more curious: the superficial
parts of some narrow ridges were as completely shivered as if they
had been blasted by gunpowder. This effect, which was rendered
conspicuous by the fresh fractures and displaced soil, must be
confined to near the surface, for otherwise there would not exist a
block of solid rock throughout Chile; nor is this improbable, as it is
known that the surface of a vibrating body is affected differently from
the central part. It is, perhaps, owing to this same reason that
earthquakes do not cause quite such terrific havoc within deep mines
as would be expected.
But his remarks on the social effects are notable too:
It was, however, exceedingly interesting to observe, how much more
active and cheerful all appeared than could have been expected. It
was remarked with much truth, that from the destruction being
universal, no one individual was humbled more than another, or
could suspect his friends of coldness − that most grievous result of
the loss of wealth.
Social reaction to a natural disaster
Though the public may be accepting of natural disaster at the time, looting
and dissension often follow. In 1906 the San Francisco Earthquake was
followed by a serious fire. While no one could blame the authorities for the
quake itself, much dissent surrounded the question of responsibility for the
fire [7, page 301]. Five months after the quake the British Consul General of
the time wrote of the insurance debacles, about the strikes and riots that he
172 Chapter 7: Protected by Physical Science
felt were gripping the city, about the fractious and disputatious mood of the
place, and of how even the local press was abandoning its eternal optimism
and beginning to ask questions about the city's long-term future.
Such a loss of trust in society seems to be the most serious avoidable
consequence of a natural disaster. Since nothing can be done about the
disaster itself, the distrust is focussed onto a secondary consequence, a
human accident around which blame and litigation can continue to rage for
many years after. In the case of San Francisco it was the fire, and at
Fukushima the release of nuclear radiation. Though precedent says that such
human reaction may be expected, the distrust may not be justified by the
evidence at all, and twenty-four-hour media enable such distrust to spread
around the world, more than in the past. This makes it all the more important
that responsible people appreciate this social phenomenon.
The public loss of confidence in nuclear power following Fukushima is the
case in point. The public should understand that from a physical point of
view, nuclear power is extraordinarily safe at the point of production – in fact
so safe that only with considerable large-scale investment and great technical
expertise is it possible to realise any nuclear energy at all. Any man-made
regulation of nuclear material is a pale shadow of the security with which
physical nature has surrounded this energy source. In his day, Darwin's
conclusions about nature were obstructed by the prevailing religious way of
thinking – today, realistic attitudes towards nature are obstructed by the
popular zeitgeist of radiation phobia.
Physical security of nuclear energy
The neutron, unique key to the nuclear energy lock
In spite of its extraordinary physical security it is just possible to unlock
nuclear energy. The key is the neutron whose existence was unknown until
1932 because it too decays (with a half-life of a few minutes) and so does not
exist freely in the wild at all. The only place that free neutrons are to be found
is inside a working nuclear reactor, and fleetingly in an exploding nuclear
weapon [8]. When a nuclear fission reactor is shut down, as was the case for
all the reactors in Japan immediately following the earthquake, the neutrons
are all absorbed and nuclear fission is halted immediately. The only further
energy release is by nuclear decay, that is the decay heat.
The neutron is the brother of the proton from which it differs only in having
no electric charge. Oblivious of the electric Coulomb barrier, a neutron can
pass freely into a nucleus.
Sometimes it just bounces off the nucleus, which may sound rather
Nuclear is for Life. A Cultural Revolution 173
unimportant, but it is the way that neutrons in a working reactor transfer their
energy to the moderator, often water or graphite. This energy is then carried
to the steam turbines to generate electricity.
Sometimes the neutron reacts with a nucleus to make a new isotope which
will usually be radioactive. This is the only way that new radioactivity is
created. Examples that have been mentioned already are the production of
plutonium, americium, cobalt-60 and tritium. When a reactor is shut down,
materials of neutron-absorbing elements like cadmium and boron are dropped
into the reactor core.
Sometimes a neutron hitting a nucleus can cause it to split in two, to fission.
In fact this is truly exceptional. Although the nucleus of iron (A = 56) is more
stable than any heavier nucleus (see Illustration 29 on page 158) fission is
inhibited by the Coulomb barrier. Without stimulation fission is suppressed
[9], but a neutron can provide the required extra fillip to an exceptionally
heavy nucleus with an odd number of neutrons, such as uranium-233,
uranium-235, and plutonium-239. Fast neutrons can cause heavy nuclei with
an even number of neutrons to fission too [10]. Only if this key is inserted into
this lock ‒ a neutron is the key and these relatively rare isotopes are the lock
‒ can nuclear energy be released by fission. No greater safety is imaginable, I
maintain.
Inherent physical safety
Fire can catch and spread to make an enlarged conflagration; so can disease,
which multiplies and spreads by infection. As described on page 166,
radioactivity cannot do this: it can be transported from one place to another,
but not increase. In fact it can only diminish with its own particular half life.
Each radioactive nucleus emits radiation just once as it changes to a lower
energy nucleus – and that is it – finish (unless the daughter nucleus happens
to be radioactive in its own right).
The rate of decay is unaffected by temperature, pressure, chemical agents – in
fact it was this property that impressed Marie and Pierre Curie most of all,
and made them realise that the radiation was coming from somewhere deeper
inside the atom than had ever been studied before. Their observation has
other more practical consequences that are seldom appreciated by those
outside the field. Because nuclear decay is unaffected at all by any other
influence, it does not matter if the radioactive material melts or boils. A
nuclear meltdown, an idea so central to many nuclear horror films, has no
effect whatever on nuclear decay. It might spill or disperse the radioactivity
into the environment, but it does not increase the amount of radioactivity or
the rate at which it decays. The popular reaction to nuclear accidents would
be more restrained if this was explained, even though it might spoil the
shock-horror impact of many fictional stories – and the mistaken descriptions
174 Chapter 7: Protected by Physical Science
by the press of actual incidents too. The decay of radioactivity is unlike the
persistence of chemical poisons, such as arsenic or lead, that remain
hazardous indefinitely. There were sad stories in the Japanese press in the
months following the Fukushima accident of people being ostracised on the
basis that they had been irradiated and might infect others. The same
happened to the Hibakusha, the survivors of Hiroshima and Nagasaki.
In their apprehension people worry that ionising radiation might cause a
particular disease or type of damage. But as explained in Chapter 5 radiation
is quite indiscriminate. It is not tuned to damage any particular molecule and
its energy is much larger than the energy that keeps ordinary molecules
together. The damage is purely molecular and electronic, and the nuclei of the
material take no active part in the impact of the radiation and the damage it
causes.
Waste from an ancient reactor
The nuclear reactor built by Enrico Fermi in Chicago in 1942 is often
described as the world's first, but, interestingly, that is untrue by a wide
margin. In the 1970s the remains of a uranium reactor that operated more
than 2,000 million years ago were discovered at Oklo in Gabon, West Africa.
It was a natural reactor that ran by itself, and when its fuel ran low the
nuclear waste that it had created stayed put where it lay. The fascinating story
is told in a Scientific American Report [11].
In uranium ore the concentration of uranium-235 in the majority uranium-238
is 0.720%. But when a rich deposit of uranium was discovered by French
geologists at Oklo, it was found that the concentration was only 0.717%.
Further detective work proved what had happened. Uranium-235 decays by
alpha emission with a half life of 700,000 years, so 2,000 million years ago
the concentration of uranium-235 must have been about 3%, much higher
than today and about the same as the enriched fuel used in many of today's
reactors. The other crucial ingredient for such a nuclear reactor is water, and
at Oklo all those years ago as the seasons came and went, the water table rose
and fell, regulating the reactor. The rare isotopes in the waste left behind have
enabled scientists to reconstruct what happened.
There is an important message in this discovery: it is wrong to suppose that
radioactive waste is just released into the environment like carbon dioxide
from combustion: the evidence shows that it may stay where it lies for half
the age of the Earth. Worries about nuclear waste leached by ground water
should be seen in proportion. There is little danger of it leaving even a
therapeutic spa for our successors.
Nuclear is for Life. A Cultural Revolution 175
Notes on Chapter 7
1) The Strangest Man A biography of Paul Dirac by Graham Farmelo, Faber (2009).
2) The strong and electric forces determine the structure of matter. In addition there
are gravity and the Weak Force (related to the electric force).
3) They are also pushed apart at short range by the Fermi degeneracy pressure, a
quantum effect that comes from the lack of distinction between protons (or
between neutrons). It also applies to electrons and is related to the Pauli
Exclusion Principle.
4) This is the point that the Churchill quotation at the head of Chapter 4 is trying to
make. It seems that he was quite well briefed in 1931!
5) http://en.wikipedia.org/wiki/Ring_of_Fire
6) Voyage of the Beagle Charles Darwin,
http://www.boneandstone.com/articles_classics/voyage_of_beagle.pdf
7) A Crack in the Edge of the World by Simon Winchester, Penguin (2006)
8) A rare exception: a tiny number of free neutrons per year are released at the top of
the atmosphere by cosmic radiation, just enough to make the few atoms of
carbon-14 whose concentration, about 1 part in 1012, is measured in the process of
radiocarbon dating used in archaeology.
9) Only 1 in 2 million uranium-238 nuclei decays by fission, even though its half
life is 4,500 million years. So without neutron stimulation the fission decay rate is
10-16 per year.
10) The variety of fast neutron reactors, actual and proposed, is summarised, for
instance, at https://en.wikipedia.org/wiki/Fast-neutron_reactor
11) The Workings of an Ancient Nuclear Reactor Meshik AP, Scientific American
(2005/9) http://www.scientificamerican.com/article/ancient-nuclear-reactor/
Nuclear is for Life. A Cultural Revolution 177
Chapter 8: Protected by Natural Evolution
Take no thought for your life, what ye shall eat, or what ye shall
drink; nor yet for your body, what ye shall put on. Is not the life more
than meat, and the body than raiment? ... Consider the lilies of the
field, how they grow; they toil not, neither do they spin: And yet I say
unto you, That even Solomon in all his glory was not arrayed like
one of these.
St Matthew's Gospel, Chapter 6
Reaction of nature to radiation
Game changing 178
Natural and responsive biological protection 178
Biology designed for survival 179
Active response to an attack 180
What happens when biological protection fails 181
Stabilisation and adaptation
Examples of stability and its characteristics 182
Adaptation, when the response learns 183
Chemical nature of initial radiation damage 184
War games of evolution 185
Energy, mitochondria and keeping fit 186
Evidence for adaptation to radiation 187
Hormesis – the by-product of adaptation 187
Effect of chronic radiation doses on dogs 189
Low-level radiation protection by regulation 191
Medical treatment with ionising radiation
Life out of warranty 191
Diagnostic imaging including CT scans 192
Isotope imaging 194
Radiotherapy – the use of radiation to cure cancers 195
New second cancers years after radiotherapy 199
Cancer induced by CT scans 200
Biological safety of radiation
French National Academy Report 202
The treatment of pregnant women and children 203
Social and mental health 205
Notes on Chapter 8 206
178 Chapter 8: Protected by Natural Evolution
Reaction of nature to radiation
Game changing
It can take a long time for the appropriate reaction to a sudden unexpected
event to become clear. Immediate conclusions reached in a state of shock can
be inept and injurious. So it was with the reaction to the terrorist attack on the
Twin Towers in New York in 2001. It was immediately assumed by the US
administration that this was a game-changing event, and that the rules and
guidance for the conduct of society, provided by justice and diplomacy and
built up over past centuries, no longer applied. More than a decade later – a
decade that saw imprisonment without trial, unrestrained state-sponsored
surveillance and wars that could not be won – it is widely agreed that the
initial flash judgement was misguided.
The detonation of the two nuclear bombs on Japan in 1945 had a similarly
profound and unbalancing effect. Suddenly the rules of life seemed to have
changed and the spirit behind the bombs appeared all-powerful. So, when it
came to matters of safety, whatever physics and physicists seemed to say was
treated with priority. The power of nuclear energy was seen to be alarming
and extra caution was readily added to match public concern, with which
those scientists not knowledgeable in nuclear physics could only agree. Only
clinical medicine continued, fearlessly and undeterred, to follow the legacy of
Marie Curie in the use of moderate and high levels of radiation for real health
benefits for many millions of people.
Natural and responsive biological protection
The effect of making health decisions based exclusively on energy needs, as
described by physical rather than biological science, may be illustrated with a
story.
A physicist and a biologist enter for a marathon to be held in three
month's time. The physicist argues that he will need to store up as
much energy as he can and so stays in bed to ensure that his bodily
reserves peak on the day. The biologist applies more common sense
knowing that life is generally adaptive in its response to stress. Each
day he runs for exercise, going a little further every time and building
up to the marathon distance. When the day of the race comes, the
biologist runs a good race but the physicist collapses well short of the
half way mark and is taken off to hospital.
Nuclear is for Life. A Cultural Revolution 179
The message is so obvious, but does it apply to the stress caused by
radiation? Unfortunately the authorities' view of its safety is to follow the
physicist and minimise the dose by staying in bed, or rather the equivalent. A
common sense view would look at the biology more than the physics – but
the biology has been largely ignored for the past 70 years.
Natural biological radiation protection is as significant as that provided by
the constraints of physical science, described in the previous chapter. The two
are complementary and the combination is outstandingly effective. Only
under exceptional circumstances is there any justification at all for adding a
third level of protection, such as regulation. The biological response ensures
that most current safety prescriptions should be redundant – such as those put
in place by authorities with an eye on the public political reaction to the
bombs of 1945 and the Cold War propaganda that followed. Unfortunately,
few physicists have any appreciation of the role of biology, and many
biologists are in awe of the physics expressed in a mathematical logic that
they are not able to follow because their education never prepared them.
Meanwhile, popular opinion, guided by politicians and the media who have
little or no understanding of either discipline, remains confused and easily
frightened. So for many decades nuclear power has been seen as mysterious
and unsafe, and therefore to be avoided whenever possible. In reality its
safety is outstanding and second to none.
Biology designed for survival
The business of life is survival, and life searches for the best design for the
prevailing conditions by trial and error. In principle, life might have existed
as a single vast organism, for instance as envisaged by the astronomer Fred
Hoyle in his novel, The Black Cloud [1] – but that would make it very
vulnerable. Biology found that survival is best assured when its chances are
divided statistically into a large number of similar elements, so that if some
happen to fail, there will be others that succeed. If some are unlucky, there
will be lucky ones too. In life this design feature is realised on two distinct
scales – the scale of individuals and the scale of cells. Society, or life as a
whole, is made of modules – individuals – and each individual is made of
cells that are also modular. A child playing with LEGO bricks quickly learns
the versatility and potential for strength that such a modularity brings. Unlike
the design of nature realised in physical science, biological realisations in
nature are not simple, unique or universal. They come in many forms – the
vast array of different animals, plants, fungi, fishes, insects, viruses and
bacteria, each competing for viability in the given local environment.
The expression of life as multiple individuals allows each to survive on its
own, and also to cooperate and work together in herds, packs or families.
They may also compete or fight one another with the benefit of internally
180 Chapter 8: Protected by Natural Evolution
selecting the strongest and fittest within the group. This improves the chances
for the herd as a whole by culling the oldest and weakest, and maximising
resources for the survivors. However, mutual help and communication
between individuals, especially within family groups, can also improve the
survival prospects for the herd as a whole.
On a microscopic scale and within each individual, the design of life repeats
the statistical strategy by building individuals from many cells. These cover
different functions, but, as with individuals, a spread of risk is achieved by
having large numbers of them that are more or less interchangeable. The
provision of master copies of the DNA, the individual's unique genetic
barcode, within every cell makes for resilience in the face of external attack.
It also acts as a personal identification system that minimises incidents of
friendly fire between cells. The affiliation of cells is policed by the immune
system which attacks any seen as foreign. Communication between cells
within an individual by chemical messaging is as highly developed as it is
between individuals in a group by speech, written and electronic means.
On each scale the design is honed to maximise survival, and everything gets
reproduced and replaced: cells are copied and die in the cell cycle;
individuals reproduce, sexually or asexually, and die. If a cell is attacked and
does not survive, there are replacements that do. If an individual dies, there
are others to take its place, because life aims for the survival of the species,
not the survival of the individual. The sanctity of life, the survival of the
individual, is not part of the scheme, and nature endures losses of individual
lives on a massive scale, which is salutary for us to remember as we face a
challenging future. Until now there has always been another distinct
civilisation to take over when one fails. But with globalisation the strategy of
survival for human society through plural diversity appears to have reached
its limit.
Active response to an attack
When life is attacked, either at the cellular or individual scale, it does not
simply rely on its passive design but has active responses as well. At a social
level, there are all the familiar defence mechanisms of individuals, separately
or jointly, including concerted military action. At the cellular level the
proteins and other working molecules of biochemical life when damaged can
be replaced by reference to the DNA as master record. When the DNA itself
is damaged it can usually be repaired without introducing an error. This is
relatively straightforward in the case of a Single Strand Break (SSB) because
the famous double stranded helical structure of DNA means that the other
strand remains attached and error-free correction is normal. If both strands
are severed, a Double Strand Break (DSB), correction is still possible and
recent work has shown how this is done [13]. Most errors that might be
Nuclear is for Life. A Cultural Revolution 181
introduced into the DNA during the DSB repair process would prevent it
being copied in the cell cycle, so the mutation does not propagate.
Furthermore, a cell with damaged DNA may be selectively killed, a process
called apoptosis. The choice between repair and replacement as the best way
to remove the damage is determined by making the optimum use of the
resources available. Nevertheless, if the mutation does get copied
successfully, the immune system continues to scan for any cell that shows
signs of not belonging. This is a major problem in transplant surgery; such
foreign cells are liable to be rejected unless the immune system has been
suppressed.
What happens when biological protection fails
The protection system has two failure modes, described in Chapter 6:
First there is a short term functional breakdown of organs caused by having
too few operational cells; typically there may be insufficient resources to
maintain both the repair of damaged cells and the cell cycle that produces
new ones by copying. Such widespread cell death first affects systems with
rapid cell cycle activity, notably the central nervous system and the gut. This
condition is Acute Radiation Syndrome (ARS) which may be fatal within a
few weeks. Otherwise, recovery is usually complete once the cell cycle has
been re-established.
Then there is longer-term failure through undiagnosed repair errors that can
give rise to uncontrolled growth of cells, injurious to the health of the
organism as a whole. Such growth, unchecked by the immune system, is what
we know as cancer. If not treated, this can develop and spread elsewhere in
the organism, hijacking resources and leading eventually to death.
Cancer induced by radiation is not generally distinguishable from cancer
initiated by other oxidative agents. Such agents occur naturally in the absence
of radiation when reactive oxidant species (ROS) leak from the mitochondria
that provide energy to cells for muscular activity, nervous communication
and the process of thinking.
We may imagine analogous failures in an army of men. The first such failure
mode is when the army is defeated through a loss of men and resources in
battle. The army is united, but the defeat is quick and decisive. The second
mode is through an insidious loss of morale, desertion or mutiny with men
turning on one another. As an illustration, these may be likened to death by
ARS and by cancer, respectively.
Historically, it was found that an exposure to radiation above a certain
threshold gave rise to a reddening and inflammation of the exposed tissue
where excessive cell death caused a loss of function in a few days. This is
like familiar sunburn, although the radiation and damage penetrate deeper.
182 Chapter 8: Protected by Natural Evolution
This early reaction is still sometimes referred to as tissue reaction today.
Then there is late reaction, an alternative name for radiation-induced disease
like skin cancer.
Other names for the two reactions, deterministic and stochastic, suggest,
deceptively, that there is more than one kind of causality at work; the data
simply show outcomes with high and low probabilities, respectively. For
example, among those who received high whole-body doses of internal Cs-
137 in the Goiania accident, half of those with more than 100 million Bq died
of ARS, including one person with 1,000 million Bq and a dose of 4,000
mGy. But another who did not die of ARS survived until 1994 before dying
of alcoholic liver failure, not directly related to radiation, in spite of an
accumulated dose of 7,000 mGy. In biology the effect of a dose varies from
patient to patient, and the label deterministic appears inappropriate.
Stabilisation and adaptation
Examples of stability and its characteristics
Illustration 30 shows an example of a curve that might describe the stabilised
response to a stress. It could apply in many different contexts, like the
management of a company, for example. Any small stress should have no
Illustration 30: A sketch graph showing a typical stabilised response
(or failure rate) to a stress,as found in electronics, management and
engineering, and characteristic overload threshold.
Nuclear is for Life. A Cultural Revolution 183
noticeable effect on the company, provided everybody concerned knows what
to do and takes action accordingly. However, there is a threshold beyond
which there are not enough staff, or not enough money, for example, to cope.
Or, perhaps, there are not enough phone lines, or warehouse capacity. There
is no need to be precise about the meaning of failure – in each context it is
usually clear. Anyway, this is where the curve rises to the right of the
threshold, and for a stress or loading that exceeds the threshold, the failure
rate rises relatively sharply.
An electronic amplifier stabilised by feedback behaves in a similar way; there
is only so much current available to provide the correcting signal, so that
above a certain threshold the feedback is no longer effective. We could look
at many more examples, but all have similar features, and there is no reason
to suppose that the response of living tissue to the stress of different radiation
doses is any different. If there is, why should that be? There is nothing
different about radiation, it is just another stress. Contributions to the
response come from the initial effect and then the correction and repair
effects, that together reduce or eliminate on-going damage.
In each example there is a time element to the story. The stress that matters
accumulates in a short time window needed for repair or feedback to act. For
the biological impact of radiation, as in the management or electronic
examples, what happens outside this recovery period is less important. As
always, empirical evidence should be the arbiter of whether this picture is
qualitatively correct or not. We need to look at further details but it is
significant that the mortality curve for Chernobyl workers (Illustration 26 on
page 136) has the same generic shape as Illustration 30 and is not a straight
line.
Adaptation, when the response learns
But the generic feedback or repair description shown by a stress-response
curve like Illustration 30 is seldom a complete description of what happens.
As a result of a stress failure or a near-miss, the shape of the curve may adapt
or change. In this way the curve itself may depend on the history of recent
stresses. For the example of a company, recent experience may persuade the
management to hire more staff, increase financial provision, install more
phone lines, or acquire more warehousing, so that next time there is an
unusual stress there will be less chance of a failure. In terms of Illustration
30, that means the curve would be shifted to the right and the threshold
raised. Such dynamic adaptation increases the likelihood that the company
survives. That is what good management does.
Indeed survival is central to the function of biology too, and it would be
surprising if such adaptation played no part in its strategy. Adaptation is what
184 Chapter 8: Protected by Natural Evolution
is happening in any fitness regime. Exercise, taken each day below the
threshold of real harm, encourages the body to improve cellular repair
resources and blood flow. Provided exercise is not excessive and damage is
not done, the improvement means that the threshold at which damage occurs
is actually increased each day. Then the exercise taken each day can be
extended without harm – there is a limit, but it is very much higher than the
limited exercise that can safely be taken by someone who lives a sedentary
lifestyle. As explained in Chapter 5 oxidative stress plays a crucial part in
physical and mental activity, and the adaptive benefit of exercise and
cognitive activity is effective in overcoming oxidative attack.
We should expect that radiation too would stimulate the cellular repair and
replacement mechanisms, so that following a radiation exposure, cells would
increase their inventory of antioxidants, DNA repair enzymes and other
defences against oxidative damage. Indeed there is evidence that they do, and
they add to resources for immunity, too. On this basis we expect that the
damage threshold would increase for subsequent radiation exposures. Do real
data suggest such adaptation to radiation actually occurs? We shall see that
they do [2, 3, 4].
Chemical nature of initial radiation damage
Exposure to radiation and muscular activity seem very different, but that is
not true of the damage they inflict. Some damage to DNA caused by radiation
is a direct collision of the radiation with the DNA molecule itself, but since
the DNA forms a small fraction of total body weight, and half of that is water,
most of the broken molecules left by radiation are fragments of water, such as
H, OH, O and H2O2, in electrically charged and uncharged states. These hot
radicals, the ROS mentioned in Chapter 5, are also made by a cell's
mitochondria, its power source. In fact it is estimated that in a single cell, 109
ROS per day are produced by normal metabolic activity – that is just over
11,000 per second [5]. Is that reasonable? In the box on the next page we
calculate how well the biology is designed.
All ROS are highly destructive, and every cell has to keep a supply of anti-
oxidants whose business is to mop up and quench the ROS before they use
their high activity to break and ionise further, otherwise undamaged, DNA. In
recent years it has been popular to take antioxidants to enhance the
suppression of early pre-cancer conditions. However, this is found to be
ineffective, probably because it is the concentration of oxidants that triggers
inter-cellular chemical messages. By taking extra antioxidants such messages
about oxidative attack are suppressed and other cellular defence mechanisms
are stood down.
Nuclear is for Life. A Cultural Revolution 185
The message to take away is that the ROS from a radiation dose and from
normal metabolic activity are chemically rather similar for many purposes,
including carcinogenesis, the tendency to initiate cancer. What is important
for control of ROS is their uniformity in space and time – short acute bursts
in time and high concentrations in space are not easily quenched.
War games of evolution
However, it is not only the response to a threat that may change and adapt,
but the threats themselves. Consider first the political world of individuals
and nations. (We will come back to the microscopic world of cellular life
later.) In that case responses to military threats are frequently explored and
evolved by engaging in war games, to find ways to out-wit the other side. An
actual engagement might go either way, depending who is the stronger or
cleverer. But if one side sticks to a never-changing strategy, then eventually
the other side should find a way to win, whatever their relative strengths.
And so it is in the microscopic world too. In the battle between cells and
viruses there are no certain outright winners – both sides are constantly
changing strategy by mutation and immunological adaptation. The battle goes
on. Sometimes the virus wins and there is an epidemic. Sometimes the
immune system with its antibodies wins, often with active help from health
programmes too.
But in the battle between physical ionising radiation and life, the situation is
quite different. The effect of the radiation is set and fixed by physical science
– it never changes. But living organisms and their cells are free to evolve and
find a defence against radiation that is more or less complete. This is true in
spite of the overwhelming fire power on the radiation side and the
extraordinary frailty of life on the other. Biology has had over 3,000 million
years to come up with its defence strategy against the seemingly all-powerful
ionising radiation.
We can do a rough calculation to check that these numbers are reasonable:
If the mass of a cell is about 10-9 g, that is 10-12 kg, then this leakage rate is
1.1×1016 ROS per kg per second.
If one ROS carries an energy of about 10 eV, that is 1.6×10-18 J,
so all these ROS comprise a power loss of 0.0018 watt per kg.
A resting human produces about 2 watts/kg. So for every 2 watts
generated, the energy lost by leakage of ROS is 0.002 watts, roughly.
So biology has evolved a power source with an inefficiency of 1 part per
1,000. That seems reasonable. Much worse would waste energy. Much
better would suggest a waste of resource and over-design.
186 Chapter 8: Protected by Natural Evolution
This is the point that mankind has failed to realise. In formulating our attitude
to radiation, we have been too readily impressed by the imbalance of fire
power without noticing the overwhelming effect of the strategic design of
life.
Energy, mitochondria and keeping fit
Keeping fit encourages the body to maintain adequate resources ready to
repair its working cells. Regular exercise is a simple way in which to raise
the norm of what the cells of an organism expect and are prepared for. At the
microscopic level the damage to be repaired is due to the oxidative processes
that we have been discussing. Energy is provided to cells by the
mitochondria, which burn nutrients taken from the blood stream using
oxygen carried by the red blood cells, and make the energy available to the
rest of the cell by means of molecules of adenosine tri-phosphate (ATP). This
process or metabolism produces about one watt of energy per kg of body
weight, enough to keep the body warm and provide the basic physical and
mental energy it needs, and where extra energy is required it provides more.
In so doing oxidative agents (ROS) may leak from the mitochondria and
inflict damage on the DNA in the cell nucleus that is indistinguishable from
the damage caused by the ROS released in the radiolysis of water – that is the
break-up of H2O by radiation.
However the energy per second absorbed from any ionising radiation is
remarkably small compared to one watt per kg, the power of metabolism
when resting. A patient receiving a course of radiotherapy gets a high
radiation dose each day: the energy deposited in healthy tissue is 1,000 mGy
per day, that is one joule per day per kg. That means that in one second the
metabolic process delivers as much energy as the patient receives in a whole
day in radiotherapy treatment. The ratio, the number of seconds in a day, is a
factor of 86,400, so it is no wonder that ionising radiation does not make the
patient feel hot – it is extremely weak. Natural background radiation at an
average 1 mGy per year is even weaker, less than the metabolic rate by a
factor of one billion. It is the leakage of ROS from the mitochondria that is
responsible for most of the natural oxidation of DNA. Adaptation, as a
response to moderate physical or mental exercise, stimulates and strengthens
protection against ROS and their effects. Radiation is no different because the
ROS and their effects are very similar, especially at low LET. This is
probably why low-dose radiotherapy, usually as whole-body or half-body,
can be effective at stimulating the body's resistance to cancer. It may be why
treatment in health spas that offer radioactive waters brings welcome relief,
even in an era when fear of radiation dominates the lives of many people.
Somehow people have allowed themselves to imagine that radiation health
from natural and artificial sources are quite unrelated. For instance, the
Nuclear is for Life. A Cultural Revolution 187
radiation in the onsen in Japan, and the Baden in Germany, is the same as the
radiation that comes from the radioactivity released at Fukushima Daiichi. In
fact both are harmless at the levels encountered, but cultural perceptions have
prevented people seeing the connection.
Evidence for adaptation to radiation
The effectiveness of regular stimulation by moderate doses of radiation
applies to the immune system as well as to the inventory of antioxidants and
DNA repair enzymes. As early as 1915 and 1920 the results of simple but
clear experiments on mice were reported by Murphy and published in the
Proceedings of the National Academy of Science [6, 7]. The experiments were
carried out on two groups of mice. Those in the first were given a single
small exposure to X-rays and a week later were injected with transplantable
cancer. Those in the second were treated in the same way but without the
exposure to X-rays. The experiment was repeated three times. In each case
the cancer infection rate for the group given the X-rays was a factor three
smaller than for those given no X-rays, as shown in Table 9.
Reference [5] Exp 1 Exp 2 Exp 3 Average
Infection rate in mice after X-rays 25.0% 29.0% 28.6% 27.5%
Infection rate in mice without X-rays 77.8% 87.5% 60.0% 75.1%
Table 9: Effect of X-rays on infected mice observed by Murphy (1915).
The experimenters found a similar stimulation by five minutes of exposure to
dry heat at 55-60oC in place of the X-rays. Evidently the increased
lymphocyte count responsible for the improved immunity could be
stimulated in different ways. The beneficial effect was not immediate and did
not persist; they found that one week was optimal. Further, if the X-ray dose
was increased even more, there was a negative effect on the lymphocyte
count.
Hormesis – the by-product of adaptation
A recent general review traces the history of the beneficial effects of low
doses of radiation back to the original discovery of X-rays [8]. As an
illustration of this positive view we sketch a possible dose-benefit curve,
Illustration 31, where the damage threshold is at point B and there is benefit
in region A. To emphasise the benefit instead of the damage, this diagram is
shown upside down compared to Illustration 30. There is a popular saying
You can have too much of a good thing. So it is with the health effect of most
agents – the right amount may be healthy, even essential, but too much is
harmful, whether it is a drink of water or a dose of aspirin.
188 Chapter 8: Protected by Natural Evolution
The principle also applies to physical exercise; some is much better
than none, but an excess causes injury. This idea was described five
centuries ago by Paracelsus, the physician and botanist (1493-1541),
who wrote, Omnia sunt venena, nihil est sine veneno. Solo dosis facit
venenum, which translates Everything is poisonous, nothing is without
poison, but it's only the dose that makes it poisonous.
With exercise or regular stimulation the point B moves to the right – each day
the damage threshold increases a little. That is, it adapts. So studying curves
misses the point – response is a live parameter, not easily tamed by
mathematics or simple diagrams. The benefit of adaptation may only last for
a certain time and may need to be stimulated again. As an example, the
efficacy of regular exercise for general health is well known [9], although
fitness does not last very long. So it is back to the gym.
But what about the body's response to radiation? That is not likely to be a
simple matter of studying straight lines or even curves, either – radiation
response seems likely to be a matter for flexible pragmatism rather than
cautionary dogma. Because the initial effect on cells of exercise and radiation
includes the chemical action that increases production of ROS, these two
elicit the same protective and adaptive responses. Thus a history of past
exercise and past radiation are both effective at stimulating adaptation. Doses
of ionising radiation at low rates suppress cancer incidence to below what
would have occurred from background oxidation in the absence of radiation,
just as exercise does.
Illustration 31: A sketch graph of a health-exercise curve indicating
some benefit for modest exercise but damage for an excess.
Nuclear is for Life. A Cultural Revolution 189
In summary, because of adaptation to past history, a response curve like
Illustration 30 tells only part of the story. For a dose below damage threshold,
beneficial adaptation does not just reduce the incidence of any cancer that
might have been caused by radiation, but it reduces the incidence of cancers
from other causes too. This effect is called hormesis, although it is of
secondary importance as far as safety is concerned. The primary question
concerns the dose rate at the threshold of damage, point B, the No Adverse
Effect Level (NOAEL), as Jerry Cuttler has called it. In summary, the point B
moves as the organism adapts.
Effect of chronic radiation doses on dogs
We are interested to find the damage threshold for a lifetime dose received as
a steady chronic dose rate. To date the most thorough experiments to answer
this question have used dogs. For a single acute radiation dose the mortality
of Chernobyl workers, shown in Chapter 6, was similar to that for a large
numbers of rats. But rodents are not suitable for whole-of-life studies of
Illustration 32: Data showing the mortality and lifespan of dogs:
(1) lifelong chronic whole-body 3 mGy daily doses of radiation;
(2) similar dogs given no dose. Data from Fritz et al [12].
190 Chapter 8: Protected by Natural Evolution
chronic doses because they have much shorter lives than humans. But dogs
live longer than rodents and a fair fraction of a human lifetime.
Lifespan and mortality data for dogs, given a chronic 3 mGy daily gamma
radiation dose throughout life, are shown in Illustration 32 [10]. This also
shows similar data for dogs who received no dose. Each plotted symbol
represents the death of a dog (some are omitted to improve clarity where they
coincide);
•the horizontal position of the symbol on the plot gives the age
in days at death (and, on the upper scale, for the irradiated
dogs, the corresponding accumulated lifetime dose at death);
•the vertical position gives the mortality of that group of dogs at that
time;
•the choice of symbol shows whether the dog died of a fatal tumour
(F) or another disease (O).
The data show that the mortality of the 92 dogs who received 3 mGy per day
is not significantly different from the un-irradiated dogs until they have
received a lifetime dose of somewhere between 6,000 and 9,000 mGy. So for
dogs, this is an estimate of the threshold we want, and, interestingly, the
symbols do not suggest that fatal cancers predominate. Such data do not exist
for humans, but the numbers are indicative for this high chronic dose rate. We
will need more such indications before we can suggest convincing safety
thresholds for dose rate and for whole-of-life dose in humans. This we do in
Chapter 9.
There is another but more sensitive way to look for changes that may give
rise to cancer, perhaps many years later. Instead of examining data on
mortality or morbidity we can look instead at the actual genetic changes
induced by the radiation. There is an important study of this kind on
genetically identical mice [11, 12]. The mice were irradiated chronically for 5
weeks at a rate of 3 mGy per day, and compared with mice a) that were not
treated at all, and b) that had received the same radiation but as a single acute
dose (100 mGy). The authors found no genetic effect at all for the treatment
of the chronically treated mice. The acutely treated mice showed genetic
effects linked to DSB only, showing that the SSB had been repaired
successfully. Evidently both the SSB and the DSB were correctly repaired for
the mice receiving the chronic dose, confirming that for mice a chronic dose
of 90 mGy per month for 5 weeks is harmless. This genetic observation is
more sensitive than a test for cancer as it is looking before the immune
system deteriorates later in life.
Furthermore, recent research on mice has successfully explained and shown
Nuclear is for Life. A Cultural Revolution 191
how DSBs are repaired [13]. This is a field in which understanding is
progressing rapidly. As far as safety regulations are concerned, the important
point is that for a chronic dose delivered at 90 mGy per month, there is no
detectable genetic damage after five weeks – and if there is no genetic
damage there can be no link to subsequent cancer. It is true that this
conclusion is for mice, not humans. But we can say that the risk of cancer for
mice is reduced by at least a factor of 50, if the dose is given chronically,
instead of acutely. ICRP guidance acknowledges no more than a factor 2
relaxation of risk for a dose delivered chronically. In the LNT model this
factor is called the Dose and Dose Rate Effectiveness Factor (DDREF) [14].
Low-level radiation protection by regulation
From the dawn of cellular life, biology has had to cope with attack by oxygen
and by radiation. Step by step it has evolved methods of protection that are
extraordinarily effective, as the accident at Fukushima and other similar
evidence have shown. None of these methods calls on the sensory system or
the brain of a living organism to do anything at all – for most of the
evolutionary span the organisms that needed protection had no such sensory
system anyway.
But now something has gone seriously wrong. What has happened? In the
middle of the twentieth century the international community suddenly
engaged with the problem of protecting life from radiation. Initially, that is in
1934, safety levels were chosen based on limited data and modest
understanding of radiobiology. Nevertheless they were quite close to those
that science would justify today. In the meantime, in the names of
conservatism and precaution it was decided to use the LNT and ALARA
philosophy, ignoring completely the understanding of modern radiobiology,
in particular the evolved protective provision that has been in place since life
began.
Illustration 5 on page 7 is a comment on the relative efficacy of the
regulatory safety system and the natural evolved one. The latter has been
honed to do the job of providing actual and immediate protection; the former
offers only bureaucratic regulation, but no active protection at all. It is time to
stop denying nature and trusting solely in regulation.
Medical treatment with ionising radiation
Life out of warranty
Evolution has delivered life designed to survive so effectively that we may
wonder why there is any need for humans to study their own survival any
further. It is true that often the best medical treatment is to not intervene and
192 Chapter 8: Protected by Natural Evolution
let natural protection apply its remedy. But this ignores the fact that evolution
has worked to ensure the survival of species, not individuals. If mankind
wants individuals to survive, medical intervention will sometimes be
necessary. Evolution has little interest in the life of individuals beyond the
reproductive and parenting age. After that individual life is out of warranty,
as it were. Only through education, the useful ongoing transfer of knowledge
from older to younger individuals, is there any evolutionary advantage in the
extension of life into old age. So medical treatment adds to what nature can
do.
Countries
by income
Mortality,
age <5yr, % [15]
Mortality,
age 15-60yr, % [16]
Life expectancy at
60, years [17]
1990 2011 change 1990 2011 change 1990 2012 change
Australia 0.9 0.5 -0.4 9.6 6.3 -3.3 21 25 +4
Japan 0.6 0.3 -0.3 8.1 6.5 -1.6 23 26 +3
Russia 2.7 1.1 -1.6 21.8 24.1 +2.3 18 17 -1
USA 1.2 0.7 -0.5 13.2 10.5 -2.7 21 23 +2
Germany 0.9 0.4 -0.5 11.8 7.4 -4.4 20 24 +4
UK 1.0 0.5 -0.5 10.4 7.4 -3.0 20 24 +4
China 5.4 1.5 -3.9 15.0 9.7 -5.3 18 19 +1
India 12.9 5.9 -7.0 27.4 20.5 -6.9 15 17 +2
Table 10: Some changes in mortality and life expectancy in recent
years.
Mortality and life expectancy have improved dramatically in recent decades
for rich and poor alike, as shown by the numbers in Table 10. Control of
disease, advances in clinical medicine, improved standards of living and
better availability of food and clean water are responsible.
Diagnostic imaging including CT scans
For most of its evolutionary development, life had a very basic nervous
system, if any. As a result the powerful brain that man has today remains
poorly informed about those processes that are active in his own body and
evolved long ago to be able to work unsupervised. Undoubtedly, given the
power of the brain, life could have evolved a broadband diagnostic network
that allowed each individual a much higher degree of self diagnosis. On the
other hand, perhaps, giving such power to the worried well to fret over their
potential ailments does not help their survival by selection. When a patient
Nuclear is for Life. A Cultural Revolution 193
presents himself to his physician, he has little to say because his brain often
has only vague ideas about his complaint. The physician needs more
diagnostic information than the patient can give. Apart from what he can
learn from a superficial examination and the patient's own account, he needs
scientific aids to probe the body using the penetration of sound waves,
radiowaves or ionising radiation [18]. These have been developed to image
both the anatomy and how it is working – a functional image. The physician
can select a method from the simple and readily available, to the finest and
most sensitive, from a low technology X-ray photography, through
ultrasound and MRI scans, to CT and radionuclide scans. All but the simplest
are in 3-dimensions, and today these can be combined to produce composite
images. They are described in accessible terms in Radiation and Reason [see
Selected References on page 279, SR3]. These advanced techniques are
becoming more and more widely available in spite of the high cost and
expertise required. The reason is that physicians find them effective and so
money is made available to pay for them. It is a good example of what public
confidence in science can achieve when the benefits are properly appreciated.
On the public side, patients are reassured to see the pictures, even though
some worry whether the methods themselves are dangerous in some way –
although they are not, and we shall see why. The radiation involved in MRI is
in the radio range and non-ionising. This has not caused the same concern
about safety as methods using ionising radiation – CT scans and isotope
scans. In fact, the power used in an MRI scan is far higher than used in a scan
based on ionising radiation. As discussed in Chapter 5, the former is
measured in watts per kg – it can only heat tissue and its safety limit is set by
comparing with the regular metabolic heating rate, a few watts per kg. The
power of an ionisation scan is measured in microwatts per kg, a million times
smaller. As explained in Chapter 5, its safety is not related to heating, but to
its effect on a minute number of individual molecules.
The number of MRI and CT units has grown very rapidly in recent years. The
extent of current provision can be judged from the data shown in Table 11.
The US authorities have reported that the mean annual radiation dose from
CT scans has risen to about 3 mGy per member of the US population,
comparable with the mean natural background and three times the suggested
limit for artificial sources of 1 mGy per year. There are two points to note.
Firstly, there can be no difference between the effect of doses from natural
sources and from medical or other artificial sources. Secondly, there is no
evidence that doses hundreds of times larger than these figures have any
negative health effects whatever. Many concerns would be laid to rest by
comparisons with information for much higher doses or by simple statistical
scrutiny. (Mistaken claims in the fields of biology and public safety often
arise from a naive use of statistics. For instance, they treat as established any
194 Chapter 8: Protected by Natural Evolution
result with 95% confidence level, without accounting that 1 in 20 such
conclusions is false. Such methods cause misunderstandings and publicity
disasters that do not occur in fields with more discipline in their use of
statistics.)
MRI CT
units examinations per
million per year
units examinations per
million per year
OECD 12 47 23 132
Australia 23 39 94
Germany 10 17 17 49
Ireland 16 15 69
Japan 43 97
UK 6 39 7 73
USA 26 91 34 228
Table 11: Scanner units and examinations per year per million population for
2009 or nearest year. [19].
Isotope imaging
The radiation of a CT scan is transitory. It passes through the body in a flash.
What is left are the broken molecules, as already described, but the radiation
itself has gone. The case of isotope imaging is different. The radioactive
isotope is injected into the patient's body and radiation is emitted as the
isotope decays. In this way the radiation is spread out by the delay of the
decay process. There are two technologies, Single Photon Emission
Computed Tomography (SPECT) and Positron Emission Tomography (PET).
The half life of commonly used isotopes are: two hours for fluorine-18 in a
PET scan, or six hours for technetium-99 in a SPECT scan. The way these
methods work is described in Radiation and Reason [SR3]. The story of the
Goiania accident, told in Chapter 6 of this book, is a graphic demonstration
that delay does not worsen the effect of a radiation dose; in fact, by spreading
out the initial damage, the repair and replacement mechanisms are enabled to
reduce long-term damage far more effectively.
The PET method of imaging gives better images at lower doses than SPECT,
but is more expensive. One problem is that, because it decays so quickly,
fluorine-18 has to be brought within a couple of hours or so from the
Nuclear is for Life. A Cultural Revolution 195
accelerator where it is made. On the other hand, technetium-99 comes from
the decay of molybdenum-99 that is produced in nuclear fission, with a
useful half life of a week, which eases the logistics of supply. Readers
worried about nuclear waste should note that molybdenum-99 is just one of a
number of valuable components of fission waste. Although PET gives better
images, its higher cost means that its use is spreading more slowly and 80%
of isotope imaging uses SPECT [20]. There are some 30 million examinations
per year, including 6-7 million in Europe, 15 million in North America and 6-
8 million in Asia/Pacific.
Cancer as a class of diseases has proved particularly difficult to diagnose and
to treat. As other diseases have been controlled or their incidence reduced,
cancer has become a more prominent cause of death. Ionising radiation, far
from being a significant cause of cancer, is a major tool in its diagnosis, and
most effective in its cure. Just as diagnosis is often more effective when
methods are used in combination, for instance PET plus MRI, so cancer
therapy often combines radiation therapy with surgery, or more often with
chemotherapy. Improved success with therapy has come with the use of real-
time imaging to target the tumour and then monitor the progress of its
demise.
Radiotherapy – the use of radiation to cure cancers
Human society is regrettably coy about talking of things thought to be
unpleasant. The hope is that someone else will deal with them, unseen by
sensitive society. For example, sewage must be reprocessed and recirculated
in a densely populated environment. It is a luxury to be able to ignore it, but
in a world facing climate change there may be more unpleasant matters that
we will have to attend to. An important early task is to identify all those
matters we prefer to ignore. The list is likely to include death and cancer, and
many people would add nuclear radiation too. In each case we are stronger
and better prepared if we study them. For instance, being hesitant about
cancer is responsible for many tumours that are diagnosed too late.
Radiotherapy is used in the treatment of cancer care not only with the aim of
achieving complete remission, but also in palliative care to reduce pain and
slow the advance of a cancer that may already have spread or metastasised. A
diagnosis of cancer is a shock to the patient, but in fact the prognosis for
many cancers today is usually good, and a majority of those receiving
therapy go home to further productive years of life. At the end of their
treatment they shake the hands of their clinician and nurses, warmly and with
thanks. This is in spite of the fact that during the 4-6 week treatment they will
have received a radiation dose to large parts of their healthy body that may be
more than 1,000 times that from a CT scan or from the radiation experienced
at Fukushima, incorrectly thought by many to be dangerous.
196 Chapter 8: Protected by Natural Evolution
The radiation used in normal high-dose radiotherapy (RT or HDRT) comes
either from a radioactive source or from a beam of electrons from an
accelerator. The latter is essentially an X-ray gun, as used in a dentist's
surgery but at higher power. Ideally the radiation shines onto the tumour and
kills its cells. The difficulty is that the gamma radiation cannot be focussed –
at best it travels in straight lines, at worst it is scattered and wanders about,
some getting absorbed by the healthy tissue in front of the tumour (unless the
tumour is on the surface) and some behind. It is this poor delivery of the
radiation dose that gives rise to the friendly fire or collateral damage inflicted
on nearby healthy tissue during the treatment of the tumour itself.
There are various ways in which the delivery can be optimised:
•By the use of gamma rays with energy well above 1 MeV to reduce
scattering and absorption for deep penetration;
•By using a number of different beam angles to deliver doses that
overlap at the tumour but spread out around to reduce the dose to
healthy tissue;
•By carefully mapping the delivered dose in 3-dimensions linked to
automatic collimators that shape the beam profile, a computerised
process called treatment planning;
•By brachytherapy, the use of low-energy gamma or beta radioactive
sources of short range, temporarily implanted in or near the tumour,
instead of an external radiation beam. Iodine radioisotopes are used
to treat thyroid cancer, one of the most successful kinds of cancer
treatment – even though at Chernobyl exposure to such isotopes may
have caused the cancer in the first place. The efficiency with which
any iodine in the body becomes concentrated in the thyroid, and
nowhere else, is responsible for both effects. The iodine has only to
be injected into the bloodstream and does not need to be surgically
implanted. Brachytherapy is also used to treat non-malignant thyroid
disorders. Iridium-192 implants are used especially in the head and
breast. They are produced in wire form and are introduced through a
catheter into the target area. After administering the correct dose, the
implant wire is removed to shielded storage. Brachytherapy is
designed to give less overall radiation to the body in cases when
radiation can be localised to the target tumour, and it is used in
particular in the treatment of prostate cancer.
•Unlike gamma rays, energetic beams of charged ions can be focussed
and targeted to stop at the depth of the tumour and deliver most of
their energy there. Such ion beam therapy is not yet available in
every clinic, but is the best for the treatment of deep cancers. In such
Nuclear is for Life. A Cultural Revolution 197
therapy, the dose can be delivered to the tumour more efficiently.
Then the peripheral dose can be reduced while the tumour dose is
increased, thereby improving the prognosis for successful treatment.
In the early days of radiotherapy, before WWI, the dose had to be given over
a period because of the limited power of X-ray machines – and patients did
well. As the equipment improved, it became possible to deliver the whole
dose in one or two sessions, but it was found that patients did not survive.
Today the dose is given in daily fractions spread over a period of 4-6 weeks
[21]. Each day the tumour cells get slightly too much radiation and die
progressively. Each day the healthy cells get about half as much radiation and
just manage to recover by the mechanisms of replacement, repair and
adaptation – in simple common sense terms, they get used to the radiation,
and this helps them to survive the extended chronic dose rate of 1,000 mGy
per day, far in excess of 0.08 mGy per month (1 mGy per year), the ALARA
limit recommended for public exposure in the environment by the ICRP [14].
Unless ion beam therapy is used, the dose that can be given to the tumour is
limited to about 2,000 mGy per day, by the effect on healthy tissue within 5-
10 cms. In a century of experience oncologists have learned that any tissue
that receives much more than 1,000 mGy per day is likely to fail as a result of
cell death; they have also learned that if the peripheral dose is reduced much
below 1,000 mGy per day, the chance that the tumour receives a sufficient
dose for successful treatment falls significantly. As described by the Royal
College of Radiologists best practice is rooted in such compromise and
empirical guidance rather than in regulation [21].
In spite of scare stories in the press, the medical use of radiation continues to
expand. The World Health Organisation (WHO) reports that the number of
X-ray examinations worldwide is more than 3.600 billion annually [22].
Currently 37 million nuclear medicine procedures are carried out and 7.5
million radiotherapy treatments are given. These numbers were posted in
2014 but the use of radiation in medicine continues to increase as the benefit
to patients gains further recognition and more equipment becomes available.
A directory of radiotherapy centres (DIRAC) has been available since 1955
and is now maintained by IAEA. Some data are summarised by geographical
zone in Table 12.
198 Chapter 8: Protected by Natural Evolution
Sub continent centres
treatment
planning
stations
therapy units
accel-
erator
external
radioactive
source
internal
(brachy-
therapy)
North America 2,787 326 4,083 158 885
Western Europe 1,039 1,587 2,552 107 427
Eastern Asia 1,934 2,113 2,048 596 222
South Asia 366 287 225 390 185
Central America 148 134 126 103 53
Africa 145 166 179 88 58
South America 494 330 560 207 203
Middle East 188 225 295 102 39
South East Asia 139 111 176 90 46
East Europe & North
Asia
406 567 487 506 277
Total 7,646 5,846 21,462 2,347 2,395
Table 12: Geographical distribution of radiotherapy centres and units
with radiation from electron accelerators and from radioactive
sources, external and internal [23].
Apparently resources are unevenly distributed. Less developed countries
have few electron accelerator therapy units as these are expensive and require
more highly trained staff. But units are available that use intense gammas
from external radioactive sources, usually cobalt-60 or caesium-137 – the
accident at Goiania described in Chapter 6 involved such a source. Ion beam
therapy requires a more powerful accelerator, but is already available in some
countries and in future it will doubtless become the preferred treatment for all
deep cancers.
Radiation dose rates in excess of 40,000 mGy per month have been in use for
over a century and accepted by the public to cure cancer in the tradition of
Nuclear is for Life. A Cultural Revolution 199
Marie Curie [21]. This treatment would be more accurately described as High
Dose Radiotherapy (HDRT). It is aimed at the offending tumour with the
intention of killing the cancerous cells, while sparing the surrounding healthy
tissue as far as possible.
There is a further way in which ionising radiation has been used to combat
cancer, and that is called Low Dose Radiotherapy (LDRT). In this case low
doses are given over a period of time to the whole body, or sometimes half
the body. The dose, perhaps 50 mGy per month, is chosen to stimulate the
adaptive reactions described in this chapter. The effect is to harness the
body's natural defences against cancer, particularly the immune system.
Success in the use of LDRT has been reported in Japan and elsewhere [24, 25,
26]. Members of the public have some general familiarity with such radiation
therapy at a low level through the popularity and benefits of spas, worldwide.
However, LDRT has yet to be as widely accepted as it may be in the future.
New second cancers years after radiotherapy
In the previous section it was stated that when planning a course of HDRT
radiologists give a tumour as much radiation as the healthy tissue around it
can withstand. That means that radiotherapy patients sometimes suffer from
Illustration 33: Plot of data from Tubiana et al showing how incidence
of a second new cancer depends on total dose absorbed (if any) in
treatment of the first cancer.
200 Chapter 8: Protected by Natural Evolution
peripheral skin burns, and also that the radiation that kills the tumour cells
may accidentally cause a new primary cancer in the previously healthy tissue.
The chance is said to be about 5%, and the cancer can usually be spotted and
treated early. It is important that authoritative data from an international
group confirm this description.
This has been provided in a recent paper by Tubiana and his clinical team in
UK and France [27]. Five thousand survivors of childhood cancer who had
received radiotherapy treatment were studied, and their subsequent health
followed for an average of 29 years. The number who developed a new
second primary cancer was 369, or 7.4%. The study asked a very interesting
question about these second cancers:
What was the total absorbed radiation dose from the first treatment
at the site where the second cancer later developed?
They were able to infer the answer from a reconstruction of the original
treatment plan. They then plotted the number of second cancers per kg
against this dose – the result is shown in Illustration 33. Along the bottom on
a log scale is the total dose in Gy (the daily dose added up for the whole
treatment) at the site where the second cancer turned up. On the left is the
cancer incidence for places far removed from the radiotherapy beams. From
this plot it is possible to draw the following conclusions:
•there is no evidence of any new primary cancer caused by a radiation
dose less than about 5 Gy, that is 5,000 mGy;
•for doses in the range 5 to 40 Gy the risk of a second cancer
increases progressively at higher dose – this is evidence for a late
response to a very high protracted dose;
•there is evidence of a beneficial suppression of cancer incidence for
radiation doses around 0.5 Gy, that is 500 mGy.
Cancer induced by CT scans
Another study, also of children, has claimed that there are health risks for CT
scan doses that are 100 times lower than the threshold shown by the
radiotherapy work of Tubiana et al. Its authors, Pearce et al [28], conclude:
Use of CT scans in children to deliver cumulative doses of about 50
mGy might almost triple the risk of leukaemia.
Many technical objections that cast severe doubt on this claim have been
published [29], but, unfortunately, when the label children is attached to a
study, the media are ready to accept any story, in spite of technical objections.
The use of the word might in the Pearce claim is characteristic of publications
seemingly designed to influence by suspicion rather than to convey any firm
Nuclear is for Life. A Cultural Revolution 201
scientific conclusion.
There is a fashion to cast doubt on the efficacy of radiation medicine and to
question the goodwill of the medical fraternity. This seems to be driven by a
wish to enhance fears of radiation, in line with the media reaction to the
Fukushima accident. A casualty is a general and unsubstantiated erosion of
trust that is itself dangerous.
But within clinical medicine the dangers are elsewhere, as observed recently
by Bill Sacks, a retired radiologist:
The craze that emerged 10 [or more] years ago for whole-body
screening with CT of asymptomatic patients resulted in a lot of harm
to patients and a little benefit. The harm, however, was not from
radiation, but rather from incidental findings which were exceedingly
common, with follow-up including such things as thoracotomies for
lung findings that needed biopsy but turned out to be benign, with all
the pain and suffering that such surgery occasioned, plus out-of-
pocket expenses. The number of false positives when you go hunting
without reason is always large. The small benefit was thought at that
time to consist of the much smaller number of patients in whom
incidental unsuspected cancers were found at early stages that were
treatable. ... the whole-body screening CTs did more harm than good,
except for the owners of the imaging centers, who usually were also
the ones to do the follow-up imaging for “incidentalomas.”
So asymptomatic patients should be worrying about subsequent procedures,
not radiation.
Symptomatic patients should not worry about radiation either. For them a
radiation scan may resolve doubts about a diagnosis. In such situations there
are several risks, some small, some large. In a recent paper Zanzonico and
Stabin [30] reported a study of the net benefit of diagnostic radiation scans for
several medical treatments. They showed that PET scans save the lives of
more than 2,000 suspected lung cancer patients a year in USA, at the expense
of a theoretical loss of 60 lives by CT-induced cancer as calculated
pessimistically using the false LNT mortality (5% per person per Gy [14]).
Similarly, they found that over 30,000 lives of coronary artery disease
patients are saved by CT scans for a dose to which the LNT attaches less than
3,000 deaths by CT-induced cancer – although there is no clear evidence for
any of these LNT risks. Thus the net benefit of a scan is quite clear whenever
there is the slightest symptomatic concern.
It is remarkable that the public and press worry about trivial risks from
radiation scans when the benefits are so evident [31]. The safety of radiation
should be a minor consideration in any decision to have frequent
202 Chapter 8: Protected by Natural Evolution
asymptomatic scans.
Opposition to CT scans on grounds of safety seldom mentions radiotherapy
with its higher doses. Perhaps that is just ignorance; perhaps it is because
details of the treatment of those who are more seriously sick, are seen as
personal and less suitable for attention-grabbing publicity. Yet people should
know that for a radiotherapy dose, a thousand times higher than CT, the
benefit of radiation treatment is overwhelming.
Here are some numbers. Over a month of a radiotherapy treatment the
tumour gets more than 40,000mGy and the peripheral healthy tissue as much
as 20,000mGy – that is five times the fatal dose experienced by some
Chernobyl workers. Evidently, the success of radiotherapy with its
fractionated treatment is witness to the biological repair mechanisms. And
everyone knows a friend or relative who has experienced this, if they have
not done so themselves. So, put simply, radiotherapy treatment of deep
cancers would not be effective if LNT were applicable, and every member of
the public has the evidence close at hand.
Biological safety of radiation
French National Academy Report
Current radiation safety regulations are based on LNT and ALARA, in part
because, in professional memory, they always have been. For most of those
with responsibility in the field, it is simply their job to follow them [32] – they
may differ somewhat from nation to nation, but by small factors compared
with what the scientific data indicate. There has not been any great pressure
to update them to match the science, because they are seen to be safe – in
respect of litigation, rather than actual danger. As long as safety levels are set
with an eye on a court of law, the answers are likely to be highly distorted.
But, with job and budget security in mind, few are interested in upsetting the
apple cart. Truth can wait – it must be someone else's problem.
However, there are two groups of professionals who have reasons not to be
easily impressed by this laissez faire position: the environmentalists and the
medical profession, at least those familiar with the science. The
environmentalists have serious questions to ask about a new worldwide
expanded use of nuclear power to replace carbon – there is no other solution
that is up to the job of providing liberal energy on the scale required. Some
environmentalists who were previously opposed to nuclear power on political
grounds have now understood the technological benefits and safeguards – we
met some of them in Chapter 2. Some radiographers, oncologists and
radiobiologists know the science and are alarmed that their patients have
been affected by a popular wave of radiophobia that discourages them from
Nuclear is for Life. A Cultural Revolution 203
accepting radiation treatment that would be beneficial to their health. The
views of the international committees that firmly resist change are heavily
influenced by American concerns – there, threats of litigation seem to be
more important than science and the environment. But an initiative has come
from the French, a unanimous Joint Report of the Académie des Sciences
(Paris) and the Académie Nationale de Médecine, published in 2005 entitled
Dose-effect relationships and estimation of the carcinogenic effects of low
doses of ionizing radiation [33]. The Report is a technical review of biological
evidence that repeatedly contradicts LNT and supports the existence of
response thresholds. A conclusion directly relevant to the application of
nuclear power is expressed in typically dry terms:
Decision makers confronted with problems of radioactive waste or
risk of contamination, should re-examine the methodology used for
the evaluation of risks associated with very low doses and with doses
delivered at a very low dose rate.
Unfortunately, neither the public nor such decision makers read these reports.
The treatment of pregnant women and children
Many a popular article about the safety of radiation includes a reference to
the sensitivity of children. The assumption is made that they are more
sensitive than adults, and pregnant mothers and foetuses more sensitive still.
Few medical accounts challenge this, but little evidence is offered either. It is
usually seen as obvious in any popular discussion. But is it true?
Without getting into details, there is reason to expect that children and
foetuses should be different from adults. Their cells divide more frequently
because they are growing and developing, rather than simply being
maintained as in an adult. However, immune protection slows with age, and it
is immune failure, not increased mutations, that increases the likelihood of
cancer.
The mutation model of cancer cannot explain the following three observed
features of cancers:
•When the immune system is suppressed, as in organ-transplant
patients or HIV patients, cancer rates more than double. Hence there
is little credibility in the prediction of a small percentage increase in
cancer from LDR based on this model.
•When people exercise vigorously and regularly – even 5 minutes of
vigorous exercise results in DNA damage [34, 35] – their cancer rates
go down considerably for many types of cancers.
•Everyone has mutations in their bodies that are potentially cancerous
but no more than half are diagnosed with cancer in their lifetime [36].
204 Chapter 8: Protected by Natural Evolution
New research shows how the immune system controls cells transformed by
low levels of radiation [37].
Less than 1% of all cancers are found in young children aged 0-14 years.
Predominantly cancer is a disease of the old, not the young, and headline
accounts of individual cases of child cancer, with the concern that they
naturally raise, should not be seen to override this general observation. This
has been checked in particular cases, for instance in careful work based on
large populations, to confirm that there is no evidence for an excess of
radiation-induced leukaemia cases among children living near nuclear power
plants [38]. In any event the size of possible doses is much smaller than
variations in the natural background radiation.
The results were recently published of an experiment designed to test the
effect of radiation on pregnancy and early development of mice [39, 40]. These
were divided into two groups, two weeks before mating. Throughout the
experiment, which lasted for up to 20 weeks from birth, the groups were
given to drink either natural water or water containing 20,000 Bq of caesium-
137 per litre. This activity in water is 2,000 times the regulation limit for
human consumption imposed in Japan since April 2013. A human drinking a
litre of such water per day, every day, would reach a steady whole-body
activity of 2.9 MBq [41], which is 30 times less than the smallest whole-body
activity that caused any loss of life at Goiania. The mice experiment observed
no significant differences in the pregnancies, blood counts and other markers
indicative of bone marrow function between the two groups. The number of
mice is not made clear, but these results are not inconsistent with the two
successful human pregnancies at Goiania and they do not suggest that a
chronic dose of caesium at this level is above any threshold that affects
foetuses or children (or adults).
Thyroid cancer in children is a special case because any iodine, whether
regular or radioactive, that enters the body gets concentrated in the thyroid
gland if the food supply was previously deficient – as was the case at
Chernobyl, but not at Fukushima. The short lifetime of radioactive iodine
means that the radiation dose is acute and confined to a small volume. These
are the conditions in which biological protection is most easily overloaded.
The same is not true for any of the longer-living caesium, strontium or other
environmentally significant radioisotopes that get widely spread through the
human body.
Whether regulations should treat children and pregnant women as a category
distinct from adults is a question separate from whether they are affected
differently by radiation. Should they be permitted radiation scans and therapy
under the same criteria as adults? That parents and husbands should take
special care of them – and exercise that care when giving permission for
Nuclear is for Life. A Cultural Revolution 205
treatment – is not the issue. Natural affection and bonding ensure that they
would do that in any event, whatever any safety regulation might say. But
should special care be taken of children and pregnant women at a legal level,
as well as a family level, when in fact there is no scientific or medical
evidence for a general increase in sensitivity to radiation? It seems unwise to
double count by stacking caution on top of itself, rather than to provide
family education and advice – as is given for sunshine and UV. There appears
to be no logical case for treating pregnant mothers and children any
differently from adults as far as regulation of exposure to radiation is
concerned. Unfortunately nobody seems ready to say this in public – another
omission that is a result of radiophobia. This is a case of confusing personal
and family care, where sentiment should have free rein, with societal and
legal responsibility, which should be rooted in objective evidence.
Social and mental health
If the physiological effects of radiation accidents have been exaggerated by a
wide margin, that cannot be said of social and mental health. Feelings of
ignorance in the event of an accident cause personal distress that can turn into
panic, especially if large numbers of people find themselves in the same
situation. If no one is ready to explain what is happening, some feeling of
mutual support is given by blaming some individuals or authorities, right or
wrong. This is a relief mechanism which gives the impression we are doing
something. Without it distress can result in mental or social illnesses of
Illustration 34: Data showing the mortality of residents in care
homes for the elderly that were evacuated in Japan [44].
206 Chapter 8: Protected by Natural Evolution
various kinds.
The elderly and less articulate are least able to take it out on someone else,
and so are worst affected. Social and mental stress may be expressed in many
diverse ways and it is not easy to find firm quantitative estimates, but social
workers are in little doubt about the symptoms that they encounter. At
Chernobyl the result was alcoholism, family break-up and states of
hopelessness [42]. At Goiania the number affected was smaller, but the stress
was expressed in cases of alcoholism and high rates of depression compared
with the national average [43].
At Fukushima there were early deaths among the elderly, bed wetting among
children, and a general witch hunt of those in authority who were thought to
be responsible. As mentioned above, this acted as a stress-relief mechanism,
but built up collectively, with encouragement from the media, into ugly
demonstrations and pressure groups which are not easily reassured by factual
explanations they do not wish to take on board. Elderly residents in care
homes are a particularly vulnerable group. At Fukushima, those who were
evacuated at short notice suffered disruption to their normal level of care in
addition to feelings of fear. Both contributed to the high mortality recorded
for residents at the time of the accident [44]. This is shown clearly in
Illustration 34 as an increase in mortality from an average of 10-20% to 65%
in the period of March 2011.
Notes on Chapter 8
1) The Black Cloud, a novel by the astronomer, Fred Hoyle, Heinemann (1957)
2) UNSCEAR Annexe B: Adaptive responses to radiation in cells and organisms
pages 185-272 http://www.unscear.org/unscear/en/publications/1994.html
3) Low-Dose Cancer Risk Modeling Must Recognize Up-regulation of Protection
L.E. Feinendegen, M. Pollycove, R.D. Neumann; Dose Response 8: 227 2010,
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2889507/
4) Hormesis by Low Dose Radiation Effects ... L.E. Feinendegen, M Pollycove, R.D.
Neumann. In Baum RP (ed.). Therapeutic Nuclear Medicine. Springer Publ., p.
789 2014 http://radiationeffects.org/wp-content/uploads/2014/08/Feinendegen-
2013-Hormesis-in-Therapeutic-Nuclear-MedicinePDFxR.pdf
5) Reactive oxygen species in cell responses to toxic agents LE Feinendegen
Human & Experimental Toxicology (2002) 21, 85 – 90.
het.sagepub.com/content/21/2/85.short
6) The effect of Roentgen Rays on the rate of growth of spontaneous tumors in mice
James B Murphy and John J Morton, Rockefeller Inst (1915)
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2125377/pdf/800.pdf
7) The Effect of Physics Agents on the Resistance of Mice James B Murphy,
Rockefeller Inst, PNAS (1920) http://www.pnas.org/content/6/1/35.full.pdf+html
Nuclear is for Life. A Cultural Revolution 207
8) Radiation Hormesis - Research Compilation
http://library.whnlive.com/RadiationHormesis/
9) Health Benefits of Physical Activity - the Evidence Warburton et al (2006)
http://www.canadianmedicaljournal.ca/content/174/6/801.full
10) The influence of dose, dose rate and radiation quality on the effect of protracted
whole body irradiation of beagles. Fritz TE. Brit J Radiol suppl 26: 103-111
(2002)
11) Integrated Molecular Analysis Indicates Undetectable Change in DNA Damage
in Mice after Continuous Irradiation at ~ 400-fold Natural Background
Radiation, Olipitz et al http://ehp.niehs.nih.gov/1104294/
http://newsoffice.mit.edu/2012/prolonged-radiation-exposure-0515
12) http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3440074/
13) Evidence for formation of DNA repair centers and dose-response nonlinearity in
human cells Neumaier et al PNAS
http://www.pnas.org/content/early/2011/12/16/1117849108.full.pdf+html
http://newscenter.lbl.gov/news-releases/2011/12/20/low-dose-radiation/
http://www.ncbi.nlm.nih.gov/pubmed/22184222
14) Report 103: Recommendations International Commission for Radiological
Protection. ICRP 2007 http://www.icrp.org
15) http://data.worldbank.org/indicator/SH.DYN.MORT
16) http://www.who.int/gho/mortality_burden_disease/mortality_adult/situation_trend
s/en/
17) http://apps.who.int/iris/bitstream/10665/112738/1/9789240692671_eng.pdf?ua=1
18) Fundamental Physics for Probing and Imaging Book by Wade Allison, OUP
(2006)
19) Data compiled in 2011 by OECD http://dx.doi.org/10.1787/health_glance-2011-
en
20) http://www.world-nuclear.org/info/non-power-nuclear-
applications/radioisotopes/radioisotopes-in-medicine/
21) Report by Royal College of Radiologists (2006)
http://rcr.ac.uk/docs/oncology/pdf/Dose-Fractionation_Final.pdf
22) http://www.who.int/ionizing_radiation/about/med_exposure/en/ [June 2014]
23) http://www-naweb.iaea.org/nahu/dirac/default.asp
24) http://www.ncbi.nlm.nih.gov/pubmed/8465019
25) http://ansnuclearcafe.org/2012/07/11/lnt-examined-at-chicago-ans-meeting/
26) Therapeutic Nuclear Medicine. Feinendegen, Pollycove and Neumann, Springer
2012 ISBN 978-3-540-36718-5 http://dl.dropbox.com/u/119239051/Feinendegen-
2012_Hormesis-by-LDR_Therapeutic-Nucl-Med.pdf
27) A new method of assessing the dose-carcinogenic effect ... Tubiana M et al,
Health Phys 100, 296 (2011) http://www.ncbi.nlm.nih.gov/pubmed/21595074
208 Chapter 8: Protected by Natural Evolution
28) Radiation exposure from CT scans in childhood ...Pearce MS et al, Lancet 380,
499 (2012). http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3418594/
29) Regarding the Credibility of data ....., Socol and Welch (2015)
http://tct.sagepub.com/content/early/2015/01/23/1533034614566923
30) Quantitative Benefit-Risk Analysis.... Zanzonico P and Stabin M, Seminars in
Nucl Med 44, 210 (2014) http://www.seminarsinnuclearmedicine.com/
article/S0001-2998(14)00014-2/abstract
31) McCollough C et al http://www.mayoclinicproceedings.org/article/S0025-
6196(15)00591-1/pdf
32) The US Environmental Protection Agency website and manual (2013) is
http://www2.epa.gov/radiation/protective-action-guides-pags
33) Dose-effect relationships and...Tubiana, M. and Aurengo, A. Académie des
Sciences & Académie Nationale de Médecine. (2005)
http://www.researchgate.net/publication/277289357_Acadmie_des_Sciences_Aca
demy_of_Sciences-
_Acadmie_nationale_de_Mdecine_National_Academy_of_Medicine
34) Exercise-induced .... oxidation Fogarty et al. Environmental ... Mutagenesis 52,
35 (2011) http://onlinelibrary.wiley.com/doi/10.1002/em.20572/abstract
35) Low dose radiation adaptive protection... Doss M, Dose Response 12, 277
(2013) http://www.ncbi.nlm.nih.gov/pubmed/24910585
36) Does everyone develop covert cancer? Greaves M., Nat Rev Cancer.
2014;14(4):209-10. http://dx.doi.org/10.1038/nrc3703 and Doss M, Private
communication
37) The role of radiation quality in the stimulation of... apoptosis ... Abdelrazak et al.
Radiat, Res, 176, 346 (2011) http://www.ncbi.nlm.nih.gov/pubmed/21663396
38) Nuclear plants do not raise child cancer risk Report of Brit J of Cancer study
(2013) http://www.bbc.co.uk/news/health-24063286
39) Biodistribution of Cs-137 in a mouse... Bertho J-M et al Radiat Env Biophys 49,
239 (2010) http://link.springer.com/article/10.1007/s00411-010-0267-3#page-1
One of several papers from this group.
40) Internal low dose in pregnant mice Lafuente D et al, Proc Meas Behaviour 2012
http://www.measuringbehavior.org/files/2012/ProceedingsPDF(website)/Posters/
Lafuente_et_al_MB2012.pdf
41) Calculated from 20,000 Bq/litre and mean retention time of 100 days / ln2.
42) Health Effects of the Chernobyl Accident, WHO (2006)
http://whqlibdoc.who.int/publications/2006/9241594179_eng.pdf
43) Valverde N., private communication
44) Mortality Risk ..... after the Fukushima nuclear accident. S Nomura et al
www.ncbi.nlm.nih.gov/pmc/articles/PMC3608616/
Nuclear is for Life. A Cultural Revolution 209
Chapter 9: Society, Trust and Safety
Ah, this is obviously some strange usage of the word 'safe' that I
wasn't previously aware of.
Douglas Adams, Arthur Dent
in The Hitchhikers Guide to the Galaxy
Establishing public trust
Earning trust and telling the truth 209
Popular culture and the Precautionary Principle 211
Innovation, leadership and confidence in science 213
Communicating truth and confidence to others 214
Recent leaders in the science of radiation 215
Confidence to change an opinion 216
Rights, duties and the survival of the fittest 218
Losing trust by offering appeasement 219
Money and safety – two social inventions of limited worth 221
Major health consequences of radiation accidents
Cancer from Hiroshima and Nagasaki 222
Inherited abnormalities caused by radiation 223
Civil nuclear safety and radiological protection 224
Radiation doses As High As Relatively Safe
Acute, chronic and lifelong thresholds of risk 225
Radiation dose rates compared using a picture 228
Largest lifelong dose that is safe 229
Origin of currently recommended safety limits 229
Conscious thought and adaptation 231
Public attitudes towards nuclear technology 231
Notes on Chapter 9 233
Establishing public trust
Earning trust and telling the truth
To the extent that people distrust one another, society fails and large
populations become unstable; instability is a euphemism – in reality it brings
a likelihood of war, famine and a dramatic fall in world population.
Improvements in living standards need individuals to develop new ideas, and
that requires imagination and creative intelligence shared with others. The
210 Chapter 9: Society, Trust and Safety
use of imagination alone too often brings apprehension of others and
misunderstandings of the natural world. It creates fear of the unknown or ill
health that needs to be challenged by evidence and study.
In earlier centuries the public could be persuaded to support national policy
through spectacular displays of military colour and fleets of ships decked
with outsized flags. But with increased education the public take more
persuasion. What they are told needs to foster trust in the authorities, but in
times of war, to deceive the enemy, the whole truth is not told. To continue
such deception is to live on borrowed time – sooner or later the truth will
come out. In the meantime an increasingly tangled web of deception is
woven. Hence the advice: Truth To Tell: Tell It Early, Tell It All, Tell It
Yourself. [1]
Since World War II the matter of ionising radiation safety has become further
and further removed from objective truth. In 1934, the year that Marie Curie
died, radiation protection recommendations were based on avoiding burns,
called tissue reactions, and the longer term effects known from the discovery
of bone cancers among the Radium Dial Painters in 1926. The
recommendations were based on a damage threshold set at 0.2 Roentgens per
day; in modern units that is 640 mGy per year of gamma rays. In 1951 the
safety threshold recommended by the International Commission for
Radiological Protection (ICRP) was lowered to 0.3 Roentgens per week,
which is 140 mGy per year. In 1955 the ICRP recommended that the use of a
damage threshold be discontinued and that the LNT model be used to assess
proportional risk all the way to zero dose. From high dose data it was judged
that the slope of the LNT straight line corresponded to an increased mortality
risk of 5% for each 1,000 mGy of whole-body dose (assumed to be gamma
rays or other low LET radiation) [2]. The vital question is why this change
was made.
Two reasons are apparent:
•epidemiological evidence of excess cancer malignancies among
radiologists, and also among industrial and defence workers;
•indications of excess leukaemia cases in the survivors of the atomic
bombings at Hiroshima and Nagasaki, whose probability of
occurrence, not the severity, was assumed to be proportional to the
size of the dose.
Today neither of these reasons look tenable. As discussed in Radiation and
Reason [see Selected References on page 279, SR3], the dominant effect
amongst groups of radiation workers and ex-workers below the age of 85 is
that they have a mortality which is consistently 15-20% lower than other
comparable groups [3]. This is true in different countries. Whether there is an
undetected selection effect, the so-called Healthy Worker Effect (HWE), or a
Nuclear is for Life. A Cultural Revolution 211
hormetic effect, cannot be determined from these data. However, claims for
small increases in cancer rates of a few percent depending on lifelong
accumulated dose have been made [3]. The doses involved are no larger than
background variations that show no such effect; the claims are of
questionable statistical significance; they cannot be taken seriously while the
much larger HWE remains unexplained and uncontrolled.
The incidence of leukaemia at Hiroshima and Nagasaki was also discussed in
Radiation and Reason, [SR3]. Among 86,955 survivors there were 296 cases
between 1950 and 2000, while data on those not irradiated suggest that there
would have been 203 cases in the absence of radiation. There was no
evidence of radiation-induced cases for doses below 200 mSv.
But starting in the 1950s there were other forces that began to influence
cultural attitudes to radiation, and Chapter 10 follows how these distorted the
views of both scientists and politicians from that time.
Popular culture and the Precautionary Principle
General education has provided little appreciation of ionising radiation and
nuclear technology. Few people go out of their way to study or attend public
lectures on the subject out of interest. Most prefer to avoid matters that they
think promise no excitement or stimulation. They are content that practical
matters are handled by consulting expert opinion, although that does not
build a sense of trust in the way that personal knowledge and experience
would. Dismissing this ignorance as a consequence of globalisation is no
solution. A few decades ago, most people could tinker with their car, and, if it
ceased to work, get it going again – but not today. Globalisation has removed
individual responsibility for many aspects of life, but some matters like the
effect of nuclear energy need to be talked through holistically – and this is
harder if the technology is obscure to almost everybody. People should have
direct or indirect contact with someone who understands and can answer
questions. That is essential to social cohesion and the stability of public
opinion.
Popular opinion is impressed by what science achieves. People notice that
science frequently consolidates its findings into principles or laws, and these
are accepted as analogous to legal laws. Then any conclusion drawn from a
generalisation that has been blessed with the title of principle or law assumes
an extra legitimacy in the public mind and is seen to need no further
questioning.
One may think of the popular Law of Averages or the Law of Unintended
Consequences, neither of which deserves such lofty status. Exactly how such
a title is conferred is unclear – but its indiscriminate use is not scientific. A
significant example is the Precautionary Principle that appeared in the 1980s
212 Chapter 9: Society, Trust and Safety
and has been used intensively in the safety industry ever since, frequently
with the effect of obstructing innovation or buttressing restrictive practices.
The pre prefix added to caution, the regular common sense word, implies a
sensible policy of additional safety during the introduction of a new
technology, for which measurement and monitoring procedures are primitive
and understanding is still uncertain. However, application of this idea incurs
extra costs and is time consuming; it leads directly to lower productivity and
uncompetitive practices in industrial applications; as soon as understanding
and information allow, it should be superseded. Its application to nuclear
technology with its advanced measuring and monitoring instrumentation, and
a century of understanding, has long been entirely inappropriate. It is being
used as a cover for public fear and to disguise the ignorance of those
supporting it.
The public believe that understanding radiation is beyond them, but for safety
at least, that is incorrect. Although they have never been told the real story of
nuclear radiation in accessible every-day terms, it is high time that they were
– at school, in public lectures and in the media. Future prospects for world
economic prosperity and a sustainable environment depend critically on
explanatory education and improved public trust in science. This is essential
if the known benefits of nuclear technology – power, clean water, food
preservation, advances in healthcare – are to be widely accepted and realised.
These are needed if man is to survive on planet Earth in large numbers with
good health and a fair standard of living.
Dangers from choice of lifestyle are often discounted relative to those seen to
be caused by the irresponsibility of others. Significant external threats to
family life may centre on economic stability and social competitiveness, but
worries that impact individuals, such as cancer and death, though far more
threatening, are personal and do not contribute to collective fear and panic. In
crowds overreaction can be reduced if enough individuals show leadership,
but others need to trust them. Otherwise, rumour, amplified by uninformed
imagination and repetition in personal and public media, becomes unstable
with the result that public confidence implodes and the mutual trust that is
essential to an effective society is seriously damaged. A similar example is
public attitudes to genetically modified (GM) crops, particularly in Europe.
Reporting on nanotechnology has had some ill-informed moments too.
As population density increases, the necessity of mutual understanding
increases too, and there is no question of going back to the way things once
were. More than ever before, it is essential that trains run on time, utilities are
delivered reliably, vehicle drivers are trained and disciplined and telephone
and internet services are up and running. For the future there is the need to
find new opportunities for economic expansion which put yet more emphasis
Nuclear is for Life. A Cultural Revolution 213
on education and building confidence in the applications of scientific
understanding.
In the past two centuries such opportunities have come from applications of
engineering and medicine, based largely on exploiting the outer (or
electronic) part of atoms – that is chemistry, electrical power, electronics,
lasers and the science of materials. But the inner (or nuclear) part of atoms
has only been exploited for health in the footsteps of Marie Curie a century
ago. The use of radiation and nuclear technology in other contexts has been
largely avoided, primarily because of the phobia felt by public and political
authorities. In an era that includes climate change that is a restriction we can
no longer afford.
Innovation, leadership and confidence in science
Science is for participants, not spectators. It should be experienced personally
in the real world through study, experiment, prediction and imagination.
Everybody on Earth is involved to an extent, and denying this reduces the
possible scope of life. Such active experience of science has lifted man above
the plants and animals and made him master of his destiny by understanding
how to solve the problems that threaten survival, not just at the level of tribe
or group but at the individual level too. Rules, customs, laws and habits
which ensure the continued existence of a group are cumbersome and apt to
change slowly – as anyone who has served on a committee is aware. An
individual who is able to deploy rational thought and apply it scientifically to
overcome the challenges he encounters, improves the life-chances for all in
the group through to an ability to change rapidly and innovate that is
excluded by the inertia of committee-land.
If everybody followed the guidance of the official consensus, many advances
in the history of mankind would not have occurred. So a balance is needed
between innovation and obedience to authority. How has this balance worked
for the wider good in the past? Who successfully combined innovation with
authority?
Science is not alone in searching for such figureheads. Think of the banks –
the issuers of bank notes denominated in the local currency – they are
concerned to impart as much gravitas and respectability as they can muster
for their notes, new and used. Whom do they select? Past monarchs and other
heads of state, especially those with reputations immutably assured by
history, but also great scientists and thinkers. In Illustration 6 on page 8 are
four such figures, two men and two women: some have much to say about
the science with which we are concerned; the others have authority and
wisdom that is no less relevant.
It was the breadth of their lives, as well as their incisive technical ideas, that
214 Chapter 9: Society, Trust and Safety
was the key to their success. Certainly none set out as an expert in their field,
since that did not exist prior to their contribution, and some of them would
have been obstructed from carrying out their work by modern regulations.
Many of their applications for research grants would have been rejected by
the peer review mechanism and, in fact, they had to overcome substantial
obstacles to get their ideas established.
Adam Smith (1723-1790), economist and philosopher, has appeared on the
Bank of England twenty-pound note since 2007. He is said to have disliked
Oxford and committees, and he lived in Scotland.
Charles Darwin (1809-1882), naturalist, biologist, geologist, and student of
divinity, has appeared on the Bank of England ten-pound note since 2000. He
had a remarkable eye for geology which seems to have inspired his view of
the evolution of life, a synthesis in tune with the writings of the
environmentalist, James Lovelock, today – or the other way around, perhaps.
Florence Nightingale (1820-1910), nurse and statistician, appeared on the
Bank of England ten-pound note from 1975 to 1994. She wrote
How very little can be done under the spirit of fear.
Marie Curie (1867-1934), physicist, chemist and pioneer radiologist, was
born Marie Sklodowska in Poland. Her portrait appeared on the Polish
20,000 zloty note in 1989 and then on the French 500 franc note in 1998.
Communicating truth and confidence to others
Thinkers like Adam Smith and Charles Darwin achieved new goals by
concentrating on fresh data interpreted with common sense and imagination.
Florence Nightingale is generally remembered for her pioneering work in
nursing at the time of the Crimean War in 1855. However, the method that
she used to promote nursing was quite revolutionary. Prior to her work,
political and military authorities had concentrated their attention on the
supply of fresh troops and munitions for the battle front and paid little heed to
the fate of the wounded. In her work she collected data on mortality rates
among casualties and analysed them to show how much more effective the
war effort would be if greater care were taken to nurse wounded soldiers. To
do this she used new graphical techniques to bring life to her data and
arguments when trying to make her point to those less gifted in numeracy.
She herself, being a distinguished early statistician, ensured that lay people
and politicians understood the implications of the data. An example of her
use of coloured charts is shown in Illustration 35. Her method and success
provide us with an important example because we try to follow the example
of her graphics when trying to bring to life the safety of radiation (Illustration
2 on page 4) and when talking of waste (Illustration 9 on page 10).
Nuclear is for Life. A Cultural Revolution 215
Recent leaders in the science of radiation
The mission to set the record straight on the relative safety of ionising
radiation is not new. A number of distinguished scientists, oncologists and
engineers who died in recent years made major contributions during their
lives to the public understanding of the effect of low doses of radiation:
Maurice Tubiana (1920-2013), a French medical physicist and oncologist. A
leading author of the highly significant 2004 French National Academies
report [4], Tubiana championed the safety of nuclear power and wrote the
book Arretons d'avoir peur! [Stop being frightened!] He was given a military
funeral in the Hotel des Invalides in Paris.
Zbigniew Jaworowski (1927-2011), a Polish physician and chairman of
UNSCEAR (1981-2).
Theodore Rockwell (1922-2013), a nuclear engineer, particularly in
submarine propulsion. A tireless campaigner for facts in support of nuclear
power.
Myron Pollycove MD (1921-2013), a radiobiologist whose clinical work and
writings contributed to our understanding of the effect of low-dose radiation.
216 Chapter 9: Society, Trust and Safety
Don Luckey (1919-2014), a biochemist who surprised the world in 1982 with
the message that low-level radiation is good for health and followed it with
the first Symposium on Radiation Hormesis in 1985.
Bernard LH Cohen (1924-2012), a physicist who staunchly opposed the LNT
model and wrote six books on nuclear physics and nuclear power.
Lauriston Taylor (1902-2004), a physicist. Charter member of ICRP 1928.
Founder and chairman for 48 years of NCRP. In a 1980 lecture [5] he made
several statements that are still relevant today:
Today [1980] we know about all we need to know for adequate
protection against ionizing radiation. Therefore, I find myself
charged to ask: why is there a radiation problem and where does it
lie?
No one has been identifiably injured by radiation while working
within the first numerical standards (0.2 roentgen/day) set by the
NCRP and then the ICRP in 1934.
An equally mischievous use of the numbers game is that of
calculating the number of people who will die as a result of having
been subjected to diagnostic X-ray procedures. An example of such
calculations are those based on a literal application of the linear
non-threshold dose-effect relationship, treating the concept as a fact
rather than a theory. ... These are deeply immoral uses of our
scientific knowledge.
Confidence to change an opinion
What is really necessary is to persuade the public that radiation is more or
less harmless at a level that anyone is ever likely to encounter – so they
should be content to embrace it. The public has a pre-existing view – they
believe that they already know that radiation is dangerous. The words of
Tolstoy quoted in Chapter 2 are worth repeating here:
The most difficult subjects can be explained to the most slow witted
man if he has not formed any idea of them already; but the simplest
thing cannot be made clear to the most intelligent man if he is firmly
persuaded that he knows already, without a shadow of doubt, what is
laid before him.
So the message that tells them that radiation is not dangerous is ignored or
treated as unwelcome. Telling people that they have no need to worry is
seldom effective.
However, there is an important group of people who have completely
changed their minds. That is very difficult to do, especially for those who
Nuclear is for Life. A Cultural Revolution 217
have been publicly active in their opposition to nuclear technology. Five of
them – Stewart Brand, Mark Lynas, Gwyneth Cravens, Richard Rhodes and
Michael Schellenberger – have made a documentary, Pandora's Promise
[SR6], directed by Robert Stone, in which they explain why they now support
nuclear energy. More important than the outstanding reviews that it has
received is the example that the film gives of people, not scientists, who have
looked at the evidence and stood up for what they now believe. There are
others too; a new website offering nuclear generated electricity in Germany
[6] went live in December 2014 with the support of former activists, founder
members of Greenpeace and other environmentalists, including Patrick
Moore, Stephen Tindale, James Lovelock and Stewart Brand.
But most people have busy lives, so difficult and confusing questions, such as
whether to use nuclear energy, have to take second place to matters of money,
children and employment. And the specialists around the world have their
professional standing and reputations to worry about, too. They are anxious
to be seen to support their own consensus and do not want to appear to
change tack – unless everybody else does too. So they have a considerable
inertia.
And the political authorities? Well, they have to face up to difficult questions
and ensure that they have the electorate behind them when they do, because
woe betide them if the lights go out on their watch. So what are they to do?
They must synchronise any change of opinion:
•They need to try to appreciate the balance of the discussion
themselves.
•They need to get the backing of the international experts – they can
hardly hold out against those who are sanctioned by the UN.
•They need to get the objective facts properly covered for the benefit
of schools, colleges and evening classes – and the teachers who cover
these.
•They must ensure that the necessary changes in policy are accepted
and supported by a majority of the public.
How such a change should be managed was described in an invited talk at the
1992 World Economic Forum, Davos, by E Schein of MIT School of
Management [7]. To introduce a real change of paradigm, as needed here, the
existing order has to be seen as increasingly threatening and the new order
has to be introduced in a positive and rewarding light. The current world
order based on the combustion of carbon (hitherto seen as comfortable and
welcoming) needs to be re-presented in its threatening colours of imminent
and unavoidable climate change. The new order has to reconfirm the headline
that with reworked regulations nuclear-generated electricity should indeed be
almost too cheap to meter. This raises an interesting question: which
218 Chapter 9: Society, Trust and Safety
commodities should not be too cheap to meter? We might suggest that water
should replace electricity as a suitable utility to be more universally and
aggressively metered – but that is another issue.
Using reason to change minds requires hard work and discipline. Evidently
the senior environmentalists who have adopted a new view have been able to
do this, but most members of the community at large have not. There is an
interesting parallel in the therapy treatment of stroke patients that requires
similar application. Following an attack, functional MR images show how the
existing mental functions of the damaged region of the brain have to be
transferred to a different, but undamaged, healthy region. This then needs to
be programmed for its new role, and the patient has to work very hard at
mental and physical exercises, with the help of therapists, for this to happen
successfully. It would seem that embarking on a complete change of opinion
on an emotive subject such as nuclear energy is a similar process. It is not
just a matter of transferring knowledge – it has to be assimilated and
accepted.
Making such a transition successfully may be eased by varying the medium
in which the case is made. Humour, music, plays, novels, video and poetry
could contribute towards establishing a change of culture. In the days of the
Cold War an important impression made this way helped to influence a
couple of generations of young people, who marched and demonstrated
against everything that nuclear energy stood for. To replace that fear and
mass dread with a cultural rehabilitation of radiation and a whole new
attitude to nuclear technology, will require a new culture that appeals to the
identity of another generation – although their loyalty will, hopefully, still be
to the environment and world peace, like their grandparents 50 years before.
But time is important. Humans may have a long lifespan, but in 50 years
much experience gets lost. Basic knowledge may be recorded, but more
subtle skills and the confidence that goes with using them are easily lost. The
experience of building railways in the UK, like the skills of ancient Greece
and Rome, were all but lost in a few generations. Much of the practical
experience of building nuclear power plants has already been lost and must
be imported – an expensive thing to do. The rebirth of a nuclear age should
not be long delayed, and educational programmes should aim to transplant
still-living experience into fresh minds before it is lost.
Rights, duties and the survival of the fittest
The survival of the fittest, the rough melee of evolutionary biology, makes no
reference to rights. Rights are additions that we have to give up occasionally
to survive, and safety is one of them. Indeed there is a tradition of honouring
those who do put aside their own safety for the sake of others on the
battlefields of war.
Nuclear is for Life. A Cultural Revolution 219
But not every such choice is faced on a battlefield. There are other much
more prosaic situations where there is a duty to step out of line and expose
personal judgement in front of others. That may require a similar mix of
bravery and self-confidence to that needed to enter no man's land and rescue
a fellow soldier under fire. Here is an example with a stark message. Over
many decades the infamous personality, Jimmy Savile, inveigled himself into
many people's confidence in UK hospitals and outside in the wider
community, and then sexually abused patients, staff and visitors, while
enjoying special open access at all times. Many suffered, many more knew,
but nobody spoke out sufficiently to question the authorities who claimed
they knew nothing about it. Nobody was prepared to put aside their own
psychological safety to save others. Duty?
Hans Christian Andersen's tale, The Emperor's New Clothes, is told to
children who find it very funny, but also appreciate its seriousness. The vain
emperor and his entourage of sycophantic courtiers stick to the official line
that he is wearing a magnificent new suit of clothes, when in fact he is
wearing nothing at all. Nobody dares to say what all can see – except a small
boy from the street who shouts out the truth. The story is a harmless rendition
of the Jimmy Savile story – but nobody spoke out in the Savile case! There
was silence, and many innocent people suffered for many years in
consequence.
Duty includes saying it how it is when everybody else appears ready to deny
it. Doing so may risk unpopularity and isolation, but what is obvious should
not be denied. If on re-examination and re-testing no flaw comes to light, it
remains undeniable.
It is interesting to read Charles Darwin's thoughts about many of the
geological rocks and fossils he found in his journey round South America in
HMS Beagle in the 1830s [8]. It was obvious to him that these were
immensely old, having started below sea level and been pushed up, heated,
weathered and broken. To him the Earth was not just old, but very much
alive, and the biblical account of the Earth, as young and dead, was entirely
mistaken.
Losing trust by offering appeasement
Equally mistaken is the account of risks to life from ionising radiation,
described by the LNT model and adopted by the current safety regulations:
these imply that all radiation doses be kept as low as possible (ALARA), the
basis for safety legislation around the world. Attempting to build public trust
by appeasing worries about safety on this basis makes several assumptions
that are untrue or damaging to society:
•It assumes that ionising radiation and radioactivity are extremely
hazardous to life. As we have seen that is not the case and we have
220 Chapter 9: Society, Trust and Safety
the evidence and explanations to hand.
•It assumes that society at large is too stupid and ill educated to
understand the simple scientific situation. This is a denial of
democracy and a council of despair – or a case for maintaining a
scientific under-class, forever stupid and uninformed, while matters
are overseen by a hegemony of safety experts. We must hope that
young people will demand to be educated and have the truth
explained – hopefully some of them are reading this book.
•It assumes that the general public has no experience of significant
radiation doses, let alone the very high doses received beneficially in
therapy and the much more moderate doses in scans. Society would
benefit from a more open explanation of such treatment by the
medical profession.
•The current safety regime assumes that the accident at Fukushima
indicated a need for greater safety in the design and operation of
nuclear plants. This is untrue. The claim suggests appeasing the
media clamour for further safety, which is a waste of resources. New
designs should be developed, and should be selected in due course on
economic as well as safety grounds. They should burn the existing
stockpile of partially used fuel, and be able to burn thorium fuel too,
but safety should not be the single priority – it certainly is not in the
carbon fuel industries. Most existing reactor designs were seen as
acceptably safe before the Fukushima accident, and should be seen as
equally safe now.
There are vested interests who have reason not to support any liberalisation
of nuclear energy and a reduction in radiophobia: those in the media who
have preached against it and taken a stand for many years; those in the safety
industry for whom the status quo offers stability of career and reputation;
others with long-term commitments to pressure groups, such as Greenpeace.
There are more who have thrown in their lot, investment or career, based
implicitly on ALARA. Few of these would welcome change, but the young
people of tomorrow whose future is at stake have no such baggage.
If the public feel that they can trust neither the science nor the authorities,
confidence is eroded and few people feel able to exercise their own
judgement. Democracy only works when voters study the actual evidence,
not just what others say about it. The voice of science itself is not democratic
– that is, its truth is not influenced by any kind of vote. Nor indeed does it
bow to authority or any court of law. Nature is the popular face of science,
and independent of any green agenda, nature will do what science determines
– and intelligent authorities know that.
Illustration 7 on page 8 may bring a smile. It tells the story of King Canute, a
Nuclear is for Life. A Cultural Revolution 221
wise Scandinavian and English king who reigned a thousand years ago. He
was pestered by his courtiers who thought only of winning his favour, and
that anything he commanded would be done. To show them this was not true,
he ordered his throne to be taken to the water's edge on the beach as the tide
was coming in. Then he commanded the tide to go out, but his sycophantic
followers were surprised to see the tide disobeyed and the water continued to
rise, lapping around the king and his throne. Man cannot stop nature, and
there is no design of nuclear power station that cannot be overwhelmed, if not
in one way, then in another. It is nobody's fault that accidents like that at
Fukushima Daiichi happen. Nature has the last word, as King Canute himself
understood.
There is no tradition that scientists take an Oath of Duty, but perhaps there
should be. Physicians traditionally take the Hippocratic Oath to place the
health and safety of their patients first. In a similar vein, research scientists
should implicitly agree to put truth about nature in first place. Then they
might appreciate how nature provides better protection than reliance on
regulation. Law, obediently followed and backed by the possibility of redress,
is no substitute for active and knowledgeable accident prevention in the first
place. A similar observation is that taking out insurance is inferior to good
care, and that a successful insurance claim never returns what has actually
been lost.
Money and safety – two social inventions of limited
worth
Insurance and legal redress come down to money. Like money, safety is a
social rather than a physical measure: both relate to contracts involving trust
and confidence within society, but both are flawed. Money is not itself
beneficial – that only happens when it is given away in exchange for
something desirable. All money must be surrendered at death anyway.
Similarly, all safety provisions must fail in the end, since death is a given for
us all.
At best, money and safety provide choices. The value of money is flexibility
in the range of goods for which it can be exchanged. But if many people
hoard it or nobody wants it, it enables no contracts and ceases to have any
dynamic value for society. Any such reduction of contracts puts a sharp brake
on social and economic activity of all kinds. An obsession with safety has a
similar effect by reducing human activity or squandering it on unproductive
investment. For example, to be safe and avoid the many small risks of the
day, to save money even, you might decide to stay in bed, thereby cutting
productivity and contributing to a decline in the economy. Safety comes at a
price.
But, if instead of a risk-averse attitude towards safety, the population at large
222 Chapter 9: Society, Trust and Safety
is more inclined to take a calculated gamble, ideally by examining the
science and reckoning the chance of success or failure, the economy would
be stimulated. The social cost of an occasional failure would be more than
balanced by the economic uplift.
So, today, how far are we from some sensible compromise or equilibrium?
Attitudes to money are poor, but perhaps not completely distorted. However,
the view of nuclear safety is so totally unbalanced that to some groups in
society, any risk at all is unacceptable, while no one else dares offend this
extreme sensitivity. The politics of this situation is stabilised by scientific
ignorance, but the economic consequences are dire and will continue to be so.
When combined with the growing use of carbon fuels, the environmental
consequences are seen to threaten the existence of human civilisation and
other forms of life.
The way in which we use safety today is equivalent to a policy of financial
liquidity in which we are so frightened that we hand all our money to the
government for safe keeping. Such a regime would have no liquidity at all,
no risk takers and no prospect of prosperity. That is not hard to see.
Major health consequences of radiation accidents
Cancer from Hiroshima and Nagasaki
There would be no particular excuse for anybody to be frightened of radiation
if WWII had not ended with two nuclear bombs being dropped on the cities
of Hiroshima and Nagasaki in August 1945. The principal effects of a nuclear
weapon are a blast, a fireball and a prompt pulse of radiation. At Hiroshima
and Nagasaki these killed at least a quarter of the population of 429,000. In
1950 when reliable records were compiled, only 283,000 survivors could be
traced, and their medical health has been followed ever since [9]. Knowing
where the bomb detonated, where the individual was and what material there
was to shield them from the radiation, enabled individual radiation doses to
be calculated for 86,955 of these survivors. These doses were checked against
the personal radiation history of individual survivors as recorded by
chromosome abnormalities and unpaired electron densities (ESR) in their
teeth. The average whole body dose of survivors was 160 mGy from the
acute X-ray and neutron fluxes. Most of those who died within days were
killed by the blast and the fire, but some succumbed to Acute Radiation
Syndrome in a few weeks. Although a few died of cancer before 1950 the
majority of such cases would be expected later, in the period 1950-2000 for
which data are available. Similar data for inhabitants who lived beyond the
reach of the radiation have also been analysed for comparison. This is
important because the normal cancer mortality rate in the absence of an
artificial radiation dose is not small, and any comparison should be made
Nuclear is for Life. A Cultural Revolution 223
with groups of inhabitants who are otherwise the same.
Of those survivors with a reconstructed dose, 10,127 died of solid cancers
between 1950 and 2000, compared to 9,647 expected based on data for those
not irradiated; for leukaemia the numbers are 296 and 203. Together these
numbers mean that 93% of cancers would have happened anyway and 7%
were caused by the radiation. For the 67,794 survivors with doses less than
100 mGy, the numbers are 7,657 and 7,595, and for leukaemia 161 and 157.
For this group of survivors the numbers of extra deaths (62 solid cancers and
4 leukaemia) are smaller than the standard random errors calculated by
Poisson statistics (90 and 13), and so are not significant measurements. But in
this group of 67,794 people the risk is only about 1 in 1,000, anyway. For
comparison, the lifetime chance of dying in a road accident varies between 3
and 6 in 1,000. So, for all practical purposes there is a threshold of risk from
a dose of acute radiation at about 100 mGy. What happens at lower doses is
too small to measure – even among the survivors from the bombing of two
major cities whose health is followed for 50 years. Perhaps it is best summed
up this way:
Suppose you were unlucky enough to be in Hiroshima or Nagasaki
when the bombs were dropped, and you survived until 1950. If you
received less than 100 mGy (like 78% of the other survivors), then
the chance that you died of cancer between 1950 and 2000 from the
radiation would be less than 20% of the chance of dying from a
traffic accident in the same period of time.
The dose at Hiroshima and Nagasaki was an acute radiation pulse with little
protracted or chronic contribution from residual radioactivity. This is the
worst case – the same total radiation dose suffered as a chronic dose due to
radioactivity spread over days, months or years would be substantially less
dangerous, thanks to biological repair, replacement and adaptation.
Inherited abnormalities caused by radiation
But cancer is not the only worry that people have had about radiation since
1945. Having learned that radiation has the power to modify DNA, there has
been concern that radiation might modify the design of human life itself, as
inherited by each generation and passed down to later ones. It is clearly
possible, but does it happen? At the time of the Cold War, imagining the
implications of this possibility increased the nuclear threat – and was,
therefore, an effective political weapon. It fuelled decades of horror fiction –
stories of two headed monsters, and pets with extra legs, made exciting
entertainment and stimulated the imagination. Unfortunately it took a few
years before the scientific consensus emerged that there is no such evidence,
based on the survivors of Hiroshima and Nagasaki, on data from Chernobyl,
or any other source. It does not happen, in humans anyway, but in the 1950s
224 Chapter 9: Society, Trust and Safety
and 1960s before this conclusion was reached, asking the question had major
consequences, as we report here in Chapter 10. But in 2007 the ICRP
cautiously reduced their risk coefficient for inherited damage to some 20 to
40 times smaller than that for cancers [10]. That inherited genetic damage has
never been seen in higher life forms is thanks to the immune system, but that
does not mean it can never occur. In principle, any of us could be hit on the
head by a meteorite tomorrow, but that is not going to happen either.
Civil nuclear safety and radiological protection
In the context of a nuclear power plant and far away from the blast and fire
caused by the explosion of a nuclear weapon, the idea of safety covers two
quite separate concerns: the control of the reactor and the protection of
people, the latter usually described as radiological protection.
Shutting down a reactor by absorbing all free neutrons stops all further
nuclear fission, but leaves unquenched the 7% of its power output that comes
from radioactive decay, the decay heat. At Fukushima the consequences of
being unable to remove this decay heat resulted in the destruction of several
reactors. Stabilising the operation of a reactor and providing cooling to
remove the decay heat are important and expensive engineering tasks. At
Fukushima Daiichi they were overwhelmed by exceptional conditions
beyond the design specification of the reactors. The result was an accident of
the kind usually labelled an Act of God in discussion of insurance risk. Put
another way, there is no human design that cannot be overwhelmed by nature.
Nobody was to blame for this and, furthermore, nobody was hurt, not even
those who worked at the plant under very difficult circumstances and took
important decisions, such as to release the excessive reactor pressures. For
that they deserve praise and thanks.
But we can ask,
Among the workers at Fukushima how many deaths due to radiation
might there be as a result of the accident in the next fifty years?
Thirty workers are reported to have received doses as high as 100-250 mGy,
but the lowest dose suffered by any worker at Chernobyl who died of ARS
was 2,000 mGy – and they died within three or four weeks. So it is not
surprising that no death from ARS has been reported at Fukushima, and none
will be in the future. What about cancer in years to come? Of the 5,949
survivors of Hiroshima and Nagasaki who received doses in this range (100-
250 mGy), 732 died of solid cancer (and 14 of leukaemia) against expected
numbers of 691 (and 15) in the absence of radiation (calculated from those
there but not irradiated). The difference, 40, is a measure of the number of
cancer deaths caused by radiation – as a proportion, it is one person in 150.
At Fukushima there were just 30 workers who received a dose in this range,
and 1 in 150 of those is 0.2. That is less than one person on average, meaning
Nuclear is for Life. A Cultural Revolution 225
that it is unlikely that any worker at Fukushima will die of cancer from
radiation, even in the next 50 years. The public have received far lower doses
than the workers and are in no danger from radiation-induced cancer
whatever.
The evacuation criterion and public exposure limit at Fukushima were based
on 20 mGy per year, but there was great public pressure to lower the figure to
1 mGy per year. Such a limit could only be interpreted as additional to
natural levels that show large variations anyway with soil type, altitude and
latitude. Even 20 mGy per year as a chronic dose is 10,000 times lower than
the monthly dose to healthy organs accepted by radiotherapy patients in
Japan – and standards of medical care in Japan are among the highest in the
world, as confirmed by life expectancy figures. The dose rate of 20 mGy per
year is 60 times lower than the conservative safety threshold of 100 mGy per
month suggested later in this chapter. Unfortunately the evacuation and
clean-up regime imposed at Fukushima has had serious socio-economic
consequences for the inhabitants of the whole region, without benefit of any
kind, and was a tragic mistake. To this should be added the major economic
and environmental cost of failing to restart the existing nuclear power plants
and the related importation of fossil fuel.
The accident at Chernobyl was more than 25 years ago and questions about
safety have been answered – what happened, who suffered and how, has been
extensively reported in publications by the World Health Organisation, the
United Nations and the International Atomic Energy Authority. The known
loss of life as a result of radiation exposure includes the 28 firefighters who
died of ARS and 15 children who died from thyroid cancer. These reports
conclude that there is no firm evidence for any other loss of life due to
radiation, either individually identified or statistically shown. The higher
numbers sometimes quoted are paper calculations that use LNT-based risk
coefficients (such as 5% risk of death per Gy) combined with measurements
of Collective Dose. If the low doses of a large number of people received
over many years are all added up, the result is a Collective Dose. This is
without meaning except in the LNT model. Since 2007, even the ICRP, that
still champions LNT, has cautioned that such calculations should be avoided.
Radiation doses As High As Relatively Safe
Acute, chronic and lifelong thresholds of risk
Suppose that you are building a bridge. Everybody agrees that it should be
cost-effective and safe. But how safe? You would not advertise the bridge
weight limit as the lowest that you might imagine by using the argument that
the lower the weight limit applied the safer is the bridge in use. By lowering
226 Chapter 9: Society, Trust and Safety
the weight limit you might incur greater risks by sending heavier trucks on a
long diversion route. Rather, safety thresholds should be set As High As
Relatively Safe (AHARS) – conservative but mindful of other risks, which is
where the relatively comes in. No extraordinary case should be made for
radiation – the record shows that there are other aspects of life that are
considerably more hazardous, and the risks and safety of radiation should be
reckoned alongside other considerations. Nuclear is not a special risk and in
fact is rather safe.
Following the discussion in Chapter 8, a sensible safety regime, conservative
and based on modern radiobiology, might place safety thresholds on:
1. a maximum single acute dose;
2. a maximum chronic dose rate averaged in any month;
3. a maximum lifelong accumulated dose to limit damage, if any, that
never gets repaired and escapes monitoring by the immune system.
The value of these high limits should be a matter for discussion based on
conservatively interpreted scientific data. If people want to impose tighter
limits in their own lives or in the care of their own families, they should be
free to do so. What they should not be permitted to do is restrict the lives of
others because of their own angst or that of a their chosen pressure group.
In 1951 the dose-rate safety level was set at 3 mGy per week (12 mGy per
month, 150 mGy per year). Although the civil nuclear radiation safety record
has remained exceptionally good since 1951, for no identifiable scientific
reason the maximum dose recommended for the general public has been
reduced by a factor 150, in pursuit of ALARA, whereas in the light of current
knowledge of the effect of radiation on human life, the 1951 recommended
value might reasonably have been increased by a factor of about eight. That
would set the limit back close to 700 mGy per year, the value set by ICRP in
1934, before the era of angst and distrust began.
Now, 70 years after Hiroshima and Nagasaki, what should we say of the
safety of radiation? It certainly can be deadly at high dose, especially if given
to the same living tissue in a short period. An acute whole-body dose of 5,000
mGy, given all at once, has the same fatal effect on cells as more than 10
times that dose, spread out over six weeks in a course of radiotherapy
treatment.
Wherever the line is drawn between what is safe and what is not, the safety
mechanism should be understood. There should be evidence to confirm the
threshold of damage, and the public should have confidence in how this is
determined. The most simply justifiable safe limit is the highest that can be
shown to cause no harm. To put it higher would not be conservative and
Nuclear is for Life. A Cultural Revolution 227
Illustration 2, A diagram showing monthly radiation dose rates represented
by the area of circles.
•Red circle, 40,000 mGy per month, less than a radiotherapy dose
rate that kills a tumour;
•Yellow circle 20,000 mGy per month, a dose rate that healthy tissue
near a treated tumour receives and usually survives;
•Green circle 100 mGy per month, a benign and conservatively safe
dose rate, As High As Relatively Safe, AHARS;
•Small black dot 0.08 mGy per month (1 mGy per yr), an
unreasonably cautious rate, As Low As Reasonably Achievable,
ALARA. (Also shown expanded for greater visibility.)
228 Chapter 9: Society, Trust and Safety
responsible. If it is put much lower the stricter regulations incur extra costs
without any known benefit. Worse, when the public do receive a dose rate
that is above the regulation level but below that which is harmful, there will
be upset, claims for compensation, even panic, without reason. To set a safety
limit As Low As Reasonably Achievable (ALARA) in a misguided attempt to
appease public radio-phobia, is to invite public unrest, mistrust and misery, as
happened at Chernobyl and Fukushima – as well as precipitating unjustifiable
added costs and environmental impact.
Radiation dose rates compared using a picture
We may wonder what diagram Florence Nightingale might have drawn at this
point to make the relative sizes of different dose rates plain for all to
appreciate. Illustration 2, copied on page 227 with a more quantitative
caption, shows monthly radiation dose rates as the areas of circles. The
largest is the red circle describing the dose rate which is fatal to tumour cells
given at 2,000 mGy in each daily treatment; the yellow circle at 1,000 mGy
daily is the peripheral dose that carries a 5% risk of causing further cancer, as
described in Chapter 8. There is no evidence for any life-threatening damage
from an acute dose of 100 mGy and, as the clinical experience of
radiotherapy has shown, a dose divided into daily doses spread over a month
is substantially less harmful than a single acute dose. It follows that a chronic
dose rate of 100 mGy per month should be even less harmful than the acute
100 mGy threshold found for survivors of Hiroshima and Nagasaki. So we
show this monthly rate, the AHARS chronic dose rate safety threshold level
as the green circle in Illustration 2. Also shown, in sharp contrast, is the
ALARA safe dose rate limit recommended by ICRP, 1 mGy per year [10] –
the area of the tiny black dot within the green circle. This is so small that it
has also been drawn in a magnified view. The AHARS dose rate is 1,000
times larger than the ALARA value but comparable with the safety threshold
set in 1934.
This factor of a thousand is a measure of the extent to which ALARA
exaggerates risk. Neglect of this factor is responsible for the socio-economic
damage of recent nuclear accidents. Only a couple of weeks was needed to
make an initial assessment of radiation exposures at Fukushima on this scale
[SR8]. With an AHARS safety level, all the evacuated residents from the
Fukushima region might then have returned to their homes to resume
productive lives. Similarly power plants in Japan might then have restarted,
and the rest of the world should then have returned to business as usual.
Actually the first did not restart until 11 August 2015, still accompanied by
protests. In due course the wreckage of the three damaged reactors has to be
cleaned up properly but there is no reason why that should stop activity in the
rest of the world.
Nuclear is for Life. A Cultural Revolution 229
Largest lifelong dose that is safe
But is this too hasty? Is there a limit to the total dose that living tissue can
withstand in a lifetime? Even if we do not know if that is really necessary, we
should use data to put a limit on it. As the years go by, this should be raised
as further data and greater biological understanding become available.
Certainly chromosome abnormalities accumulate, but it is the health of the
immune system that is crucial. Anyway we should let mortality data answer
the question. What figure do presently available data suggest? We saw in
Chapter 6 that the threshold lifetime dose for cancer among the Radium Dial
Painters is 10,000 mGy, a whole-body dose delivered chronically by the
radium in their bones, although this alpha radiation is considered 20 times
more damaging per Gy than beta or gamma radiation. So 10,000 mGy should
be an underestimate of the lifetime tolerance for beta and gamma by a large
margin.
There are two other estimates that are relevant. There is the threshold for a
second cancer seen at about 5,000 mGy, Illustration 33 on page 197, although
that dose is received locally in six weeks, not to the whole body in a lifetime.
That means that the threshold 5,000 mGy, considered as a whole-of-life
figure, could be a significant underestimate.
Finally there are the beagle data for a lifelong chronic dose rate of 100 mGy
per month that showed no sign of life shortening until the dogs had received a
total whole-body dose of between 6,000 and 9,000 mGy, Illustration 32 on
page 187. This is the threshold value we are looking for, except that it is
measured for dogs rather than humans.
Nevertheless there is some consistency between these three sets of data that
suggests that 5,000 mGy would be a conservative value for a whole-of-life
dose limit – it is as low as any of them. It corresponds to more than four years
of receiving the AHARS maximum monthly dose rate of 100 mGy per
month.
These safety thresholds are particularly cautious because they take no
account of the beneficial adaptive effect of low-dose-rate radiation that can
stimulate cancer resistance. This important possibility is really a matter for
medicine, not safety regulation. But it does mean that in general there may be
a dose-rate at which the positive stimulation balances the negative
carcinogenesis. This has been called the No Observed Adverse Effects Level
(NOAEL). However, it is too simplistic to see this as a single point on a
curve. Its movement with the time profile of dose delivery and any
subsequent morbidity will be important too.
Origin of currently recommended safety limits
Where did ALARA, the current ultra-cautious safety guidance, originate? As
230 Chapter 9: Society, Trust and Safety
we shall see in Chapter 10, it is a product of history and politics, not
considerations of science or safety. Its parentage has ensured that it carries
the full weight of a UN recommendation that leaves limited choice to
national authorities. Only the bravest government would ignore the guidance
provided by the ICRP, backed by the IAEA – and this guidance is to keep all
radiation doses As Low As Reasonably Achievable. Any government that
ignored such advice would risk being pursued by a frightened populace and
soon be out of office. Worse, faced with any case brought to a court of law,
any authority might wish it had played safe, as the law might see it. However,
a court of law is a most inept forum in which to contest science. Education of
the populace is a cheaper and more positive way ahead, but that takes time.
So, if national authorities are not to blame, it must be the fault of the ICRP
who made such recommendations. Well, yes, but the original fault should be
laid at the door of all those around the world who from the 1950s to the
1980s and even today, demonstrated, marched, sat in, chanted and voted with
a popular voice for a world with minimal radiation. ALARA is the result and
it is the fault of everybody who expressed their views so strongly at that time.
However, now they should think again – and many have done so. Politicians
and those with entrenched views should realise that times have changed and
that radiophobia was never based on science in the first place.
What should be done now? If we do not want to succumb to the worldwide
catastrophes that seem likely to accompany an ever more polluted
atmosphere, we must reverse public perceptions of radiation and engage with
nuclear energy as soon as possible. That will require a culture of public trust,
based on a vigorous but sympathetic educational programme about radiation
science. Should that be all so difficult? The public already has a fairly
balanced attitude to radiation from the Sun and a degree of confidence about
radiation in clinical medicine. Public perceptions can switch much faster than
many imagine – just think how quickly attitudes to smoking have turned
around, not just in one country, but almost universally. Perceptions of
refugees change monthly as the public switch between identifying with their
plight and otherwise.
New realistic safety regulations should bring major cost savings to any
nuclear programme. Cheaper electricity would influence the public view, but
first it needs to be offered. While no corners should be cut in respect of the
control of reactor stability and its heat output, with justifiable safety
standards, large parts of the cost of nuclear power could still be dramatically
reduced, whichever flavour of future nuclear technology is chosen. Matters of
nuclear waste, reprocessing and decommissioning should take their place
lower in the list of priorities alongside other environmental problems
requiring responsible and transparent solutions, like the disposal of hazardous
chemical and biological waste.
Nuclear is for Life. A Cultural Revolution 231
We have survived on planet Earth, more successfully than other animals,
through an ability to think rationally. In the past 60 years we have stopped
thinking and become scared of the solution to our predicament. We should
admit our error and turn about. That means public information, schools
programmes, new national regulations, new working practices, new cost
estimates. With the reach of television and the skills of people to harness
social media to a cause that should be seen as theirs, it ought to be possible to
make the change. Some will see this task as impossible, but they should heed
the advice seen recently at the foot of an academic email: Those who say it
cannot be done should not interrupt those who are doing it.
Conscious thought and adaptation
Life is a struggle, sometimes against unseen forces, often against intense
competition. To an individual in society, success in life may be expressed in
terms of money. Money is but a means of exchange, giving choice and access
to the real goals of freedom from fear, access to food, water, warmth and
shelter. To the ambitious, what is important may be a position in a virtual
pecking order, but for society as a whole, success is marked by a healthy
population at peace with itself. Natural calamities, epidemics, internal or
external strife, and the effects of over-population endanger this. At a global
level money is a means of organising how human effort is distributed and
motivated, although it is often not effective at that.
If humans planned to live the simple life on earth, there would be no need for
further adaptation of life through cognitive ideas. But that is not the case. We
no longer have a small population with short lives limited by the natural
diseases of ageing. So we need to understand the biology of life sufficiently
well to modify it and understand, too, the social implications of the
technologies we use and how they relate to health and the environment.
These are questions for which evolution has not already prepared us.
Everybody needs a more holistic understanding of life and the environment.
Public attitudes towards nuclear technology
In particular, we need to understand nuclear technology, its impact on health
and what it can do for the environment. Even though few people currently
understand it, there is no reason why the subject should be seen as more
obscure than other branches of science. As a cure for cancer it has been an
important part of the ability to extend life for over a century. However, its
role in politics and the environment has been seen as destructive and in the
interest of no one. The science has been shunned by many and the general
population has not been encouraged to find out more. The number and status
of the international committees who pronounce on nuclear matters has grown
because of official and public ignorance. As both officials and the public
become more knowledgeable, as they should, these committees and their
232 Chapter 9: Society, Trust and Safety
influence should be pruned.
The present clash of views over the safety of nuclear technology is
remarkable, because there is no real danger – at least none comparable to the
dangers of fire or road traffic. Reactors may have been destroyed at
Fukushima, but there has been no significant detrimental health effect from
radiation. Even at Chernobyl, where the reactor was utterly destroyed, there
were only 42 known deaths actually caused by radiation. Radiation deaths
from nuclear accidents are zero or few, except for theoretical phantoms based
on paper calculations with LNT. So it would seem that, while the fire antis of
long ago had good grounds for safety concern, the nuclear antis of today have
none for low or moderate doses.
What about radioactive waste and nuclear terrorist threats? Public
misinformation and panic apart, these are only dangerous to the extent that
radiation is dangerous. If the dangers of radiation have been overestimated,
then waste is less of a problem, and nuclear terrorism too. Up to now the
public have viewed nuclear waste and the threat of terrorism as unbounded
horrors. This is not justified by science – it is mistaken. Public fear and panic
is a quite different problem that needs a quite different targeted solution.
Nuclear waste, though nasty stuff, does not spread or infect like fire or the
disease encouraged by biological waste. Because nuclear energy is so
concentrated, little fuel is used and little waste is created – about a millionth
as much as for fossil fuel. The waste needs to be cooled, reprocessed (to
retain the valuable unused fuel) and the remainder buried after a few years –
no bigger a task than handling many chemical waste products whose toxicity
persists indefinitely. The effort and expenditure lavished on nuclear waste
and plant decommissioning should be reduced; the cost saving should be
substantial though vested interests would have their own reasons to argue
against that.
If we follow the urgings of the anti-nuclear advocates, our prospects on
planet Earth will be no better than animals, a massive reduction in numbers
with a low standard of living. So we should study and apply knowledge, as
our forbears did with fire. Though they were faced with a finely balanced
dilemma, they did a better job at decision-making than we have done
recently. Generally, those in authority have little understanding of science,
although new prosperity depends on scientific innovation, as it has in the
past.
Great rewards will be reaped by the countries that first set aside the legacy of
the LNT model and embrace cost effective nuclear technology with sensible
safeguards. As well as electric power, this technology can provide large
quantities of fresh water by desalination, harmless and cheap food
preservation by irradiation without refrigeration, and further advantages in
Nuclear is for Life. A Cultural Revolution 233
medical care. The world needs these opportunities to expand economically
and socially, but the philosophy of ALARA and LNT stands in the way. The
great eighteenth century economist, Adam Smith, said:
Science is the great antidote to the poison of enthusiasm and
superstition.
He saw clearly that unless excessive activity caused by enthusiasm or the
suppression of activity caused by superstition is properly rooted in science,
its effect is poisonous. As we have seen fear of nuclear energy is a
superstition without scientific foundation that should be exposed for what it
is – or its demons exorcised, as the mediaeval church might have expressed
it.
Notes on Chapter 9
1) Notes from My White House Education Lanny J Davis (2002)
http://www.amazon.com/Truth-To-Tell-Yourself-Education/dp/0743247825
2) What Becomes of Nuclear Risk Assessment in Light of Radiation Hormesis JM
Cuttler (2007) http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2477701/
3) Mortality and Cancer Incidence ... in the National Registry of Radiation Workers
Muirhead CR et al, British Journal of Cancer 100, 206 (2009)
4) Dose-effect relationships and...Tubiana, M. and Aurengo, A. Académie des
Sciences & Académie Nationale de Médecine. (2005)
http://www.researchgate.net/publication/277289357_Acadmie_des_Sciences_Aca
demy_of_Sciences-
_Acadmie_nationale_de_Mdecine_National_Academy_of_Medicine
5) Some nonscientific influences on radiation protection standards and practice.
Taylor LS The Sievert Lecture 1980. Health Physics 39: 851-874
6) Environmental and other academic support for German nuclear power (2014)
http://maxatomstrom.de/umweltschuetzer-und-wissenschaftler/
7) How can organisations learn faster? Schein EH, MIT Sloan School of
Management http://dspace.mit.edu/bitstream/handle/1721.1/2399/SWP-3409-
45882883.pdf?sequence=1
8) The Voyage of the Beagle Charles Darwin,
http://www.boneandstone.com/articles_classics/voyage_of_beagle.pdf
9) These data are discussed and tabulated in more detail, including references, in
Chapter 6 Radiation and Reason [SR3]
10) Report 103: Recommendations International Commission for Radiological
Protection. ICRP 2007 http://www.icrp.org
Nuclear is for Life. A Cultural Revolution 235
Chapter 10: Science Distorted by
Frightened Men
Fear does not prevent death. It prevents life.
Naguib Mahfouz, 1988 Nobel Prize for Literature
Evolution after Darwin
Faster development and greater personal threat 235
When evolution met radiation: Hermann J Muller 237
Nuclear weapons and the Cold War
A year that made history and buried truth 238
Dissent over nuclear weapons 238
The madness of the Arms Race 240
Chronology of nuclear turning points 241
Public exposure to radioactivity from weapons
Nuclear testing in the atmosphere 243
Anti-nuclear demonstrations in free countries 244
Fallout in fact – The Lucky Dragon 245
Fallout in fiction – On the Beach 246
Warnings from the intellectual elite
Russell-Einstein Manifesto 247
Linus Pauling to President Kennedy 248
A game of nuclear chicken
Cuban Missile Crisis 250
Radiological protection and the use of the LNT model
US National Academy of Sciences genetics panel report 250
Safety not fit for purpose 251
Notes on Chapter 10 253
Evolution after Darwin
Faster development and greater personal threat
To develop productively and peacefully, civilised society needs both trust and
knowledge. Marie Curie gave both when she introduced radiation and nuclear
technology into medicine. So the public acceptance of ionising radiation
236 Chapter 10: Science Distorted by Frightened Men
started well and she was active herself in organising the use of X-rays for the
casualties of battle during WWI [1]. However, later in the twentieth century,
when radiation and nuclear technology made an appearance in the form of
nuclear weapons, knowledge was explicitly suppressed in the name of
security and there was no figure like Marie Curie to instil public confidence.
How did this go wrong? We need to go back in time.
In the nineteenth century Darwin introduced his revolutionary biological
ideas of variation, selection and survival, as applied to living species. Over
time most of human society came to understand and accept these, in spite of
their revolutionary effect on our view of ourselves in the world. Perhaps this
was because the changes that evolution described acted relatively slow, and
an individual's perception of himself and his immediate family did not feel
much affected. So, though knowledge was thinly spread, trust was not
seriously impaired and variations in family ancestors, desirable or not, were
safely removed to prehistory.
The principle of selective breeding of humans is a natural extension of the
improvement of plants and animals, as practised from earliest times. But,
independent of Darwin's ideas, the manipulation of human characteristics
through planned breeding is widely seen as taboo and excites strong passions.
Nevertheless, it was in fact Darwin's relation, Francis Galton, who in 1883,
the year after Darwin's death, introduced eugenics, the name for this study.
Darwin developed his ideas to describe the development of populations of
organisms – that is whole individuals. Later, the same ideas were applied to
populations of cells including viruses and bacteria, where the timescales of
change are much faster. With a cycle time of a few weeks cells can turn over
hundreds of times in a human generation, and other constituents of
microscopic life like bacteria and viruses evolve faster still. Evolution on this
scale gave a picture of cellular life that might, even in the short term, be
manipulated or artificially engineered for nefarious or political purposes. This
picture alarmed the public in a way that Darwin, with his account of the
characteristics of the finches observed on the Galapagos Islands, never did.
However, what Darwin's theory did not describe was how the genetic record
might be systematically changed, that is how mutations might be induced in
the DNA. The power to manipulate would depend on controlling these
mutations, but the structure of DNA would have to be found first.
It is not widely known that in the years before WWII X-rays were used with
some success to control infection [2]. However, this work was cast aside in
the enthusiasm for antibiotics when these became available to treat infections
on the battlefield. If the current increase of antibiotic resistance continues,
perhaps this use of X-rays should be considered again – but that is an aside.
After WWI there was increasing disquiet as the Soviet and Nazi authoritarian
Nuclear is for Life. A Cultural Revolution 237
regimes grew and industrialised military interests expanded with them. The
Nazis engaged in experiments in eugenics in pursuit of their racial ideas
although with limited success. However, a more significant development
dates from the 1920s and even before, when it was shown that X-rays could
create random mutations in fruit flies, as first studied by Hermann Muller. It
was at this point that ionising radiation first entered the story that later
became radiophobia.
When evolution met radiation: Hermann J Muller
Hermann Muller (1890-1967) was an American geneticist with outspoken
political beliefs and an early interest in eugenics – he even named his son
Eugene. In 1926 he published his experimental results on the production of
mutations in fruit flies by X-ray radiation. Later, in 1946 he was awarded the
Nobel Prize for this pioneering work. Significantly, in his lecture he claimed
that any radiation dose produces genetic damage in direct proportion, all the
way down to zero dose [3, 4, 5]. This was the birth of the LNT model, but in
making this claim he says these principles have been extended to total doses
as low as 400 r. In modern units that is 4,000 mGy – which is a very high
dose indeed, high enough as an acute dose to have killed the firefighters at
Chernobyl. So he did not establish the LNT model for low or moderate doses
found in the environment. Since then, other work has shown that the LNT
model does not fit low-dose data for fruit flies [6]. Nevertheless, he continued
to claim that the response to such doses is linear all the way down to zero, as
now enshrined in the LNT model.
Elsewhere in the middle of the twentieth century, biology became entangled
with politics and made other wrong turns. In the Soviet Union, Trofim
Lysenko, an agronomist, persuaded Stalin that Soviet agriculture should deny
the principles of Mendelian genetics and develop crops based on the principle
of the inheritance of acquired characteristics, as suggested by the Frenchman
Lamarck (1744-1829). Unsurprisingly the programme failed and many
inhabitants of the Soviet Union died of starvation as a result. The application
of this fallacious pseudo-science was not finally halted until 1956.
Although both the LNT model and Lamarckism are mistaken, the former still
has vocal supporters who are reluctant to look at the evidence. In the same
way, even today, in parts of the USA, opposition to Darwin's ideas is seen as
a belief – a political or religious question. Some people, it seems, live their
lives knowing the answer as they see it, without ever looking at the evidence,
but that is not an effective way to avoid danger.
However, the public perception of physical science was derailed in the
middle of the twentieth century by a quite different mechanism, such that it
was then seen as a closed book, shrouded in mystery and secrecy.
238 Chapter 10: Science Distorted by Frightened Men
Nuclear weapons and the Cold War
A year that made history and buried truth
The end of WWII and other events in 1945 coloured how the birth of nuclear
weapons was received. In that year the public of every nation were steeped in
daily accounts of horror and war that are not easily forgotten, even with the
passage of time. On 15 April British troops entered the Bergen-Belsen
concentration camp, and in the following few days the public were shown
press pictures of piles of naked bodies, evidence of tens of thousands dying
of starvation and disease [7]. So the media were already experienced in the
transmission of genuinely shocking news when in August the official reports
arrived of the two nuclear bombs dropped on Japan. Each nuclear explosion
caused a blast wave and a heat wave that destroyed buildings and killed most
people within a radius of about 1 mile, and generated a fire-storm over 4.4
square miles [8]. The death toll was said to be less than in the conventional
fire-bombing of Tokyo six months earlier [9], but peculiar to the nuclear
explosion was the intense flash of X-rays and the lesser flash of neutrons
emitted from the detonation point at a height of 500-600 metres. Because the
explosion was high above ground there was less radioactivity released than
would have been the case for a detonation at ground level. As a result, the
inhabitants received acute doses of radiation, with less chronic dose from
fallout.
The historical narrative that one usually reads is what the victors wrote, but
more significant for the subject of this book is what the vanquished thought
of the nuclear bomb. They learned of its power when at their lowest
psychological point, and their national consciousness has been branded by
the thought of it ever since. It is no coincidence that the most visceral
reactions to the accident at Fukushima have come from Japan and Germany.
But with the passage of years those reactions should be tested against
science. When writing the account of Fukushima for the sake of future
generations, the world has a duty to ensure the story is honest and scientific,
not emotional.
Dissent over nuclear weapons
But after WWII the victors were troubled too. Though a scientist may respect
the science and its reliability, his fear of what his fellow human beings may
do with the power it gives them is increased by his technical understanding.
Fears of Nazi Germany and the Soviet Union were rife in the twentieth
century, but there were also worries on the US home front about politicians,
military leaders, fellow scientists and foreigners who held a variety of views
on how science should be used. Nuclear energy, by its very power, intensified
questions of trust, confidence and secrecy [10]. Significant tensions built up
Nuclear is for Life. A Cultural Revolution 239
between individual scientists, and also between other groups involved; and
these were not eased when peace came. Worries about war-time allies,
particularly the Soviet Union, grew too.
Unlike science, history often provides several coherent accounts of a maze of
events from different perspectives. Thus the military and political
perspectives of the history of nuclear radiation are not based in science. In the
development of nuclear weapons in WWII, the raison d'être of the Manhattan
Project, there were many major players who were not scientists, and
misunderstandings between them and the physical scientists continued to be
important into the Cold War era. It could be argued that the lack of
confidence and mutual trust between these two groups was as instrumental in
the rise of radiophobia as the ingrained fears of the defeated populations.
Many of the physical scientists involved were in some shock when they
realised the energy of what they had developed, and had little confidence in
the readiness of the military to forego the influence of this muscle at the end
of hostilities with the Axis Powers. Their concern was well founded, for other
nuclear scientists threw themselves, without a second thought, into building
the most powerful weapons possible, in particular the fusion device known as
the hydrogen bomb. A conventional fission bomb is limited in size and power
by the speed at which it is possible to assemble a large super-critical mass of
explosive. But a fusion bomb has no such limit, and the Soviets tested a 50-
58 megaton device, about 2,000 times the energy of the Hiroshima and
Nagasaki explosions.
Political and military concern, particularly in the United States, was focussed
on fears that other powers might obtain the secrets of nuclear weapons. As a
result the development of the hydrogen bomb was supported amid tight
security. Exceptional scrutiny was applied to root out any potential Soviet
sympathisers, and the sharing of information with other allies, even the UK,
was curtailed. A reign of anti-communist hysteria, verging on paranoia,
ensued: there were the Senate subcommittee McCarthy-Army hearings of
1954 about claims of communist infiltration; there were the investigations of
the House Un-American Activities Committee with its witch hunt for
communist sympathisers; there was the investigation of the patriotic loyalty
of Oppenheimer before the US Atomic Energy Commission. Dr Robert
Oppenheimer was the physicist war-time leader of the Manhattan Project
whose security status was revoked in 1954, largely on the testimony of
Edward Teller, the Hungarian-born theoretical physicist who pushed the
development of the hydrogen bomb. The late 1940s and early 1950s were a
dark period in the USA – many liberties that we normally take for granted
were suppressed. The lives of many eminent people were seriously damaged
and they went into hiding, or went abroad, like Paul Robeson, the legendary
actor and singer, and Charlie Chaplin, the film director and comedian. It is
240 Chapter 10: Science Distorted by Frightened Men
helpful to appreciate this turbulent background when judging the scientists
and scientific opinion of the day – opinion that led to the establishment of the
LNT model and the suppression of contrary views for over 60 years.
How scientists express their concern on matters beyond their own immediate
field varies, but their natural discipline makes them cautious – in fact
considerably more cautious than those unused to scientific argument. Since
few physical scientists and engineers appreciate much about biology, and
biological scientists know very little of nuclear physics, they are frequently
rather over-awed by their shared interdisciplinary questions. That was the
case in the Cold War era in the matter of nuclear radiation and its biological
effects, particularly genetics. At a crucial time in the 1950s as the official
view was forming, the voice of biology was missing. In the confrontations
between the main parties, the military and the physical scientists, nobody
could speak to the biology with the required authority. There was no biologist
on the Manhattan Project with the necessary clout, and the mode of scientific
thinking in biology is quite different from that in the physical sciences, as
explained in Chapter 4. And into this gap came Hermann Muller, recently
anointed Nobel Laureate (1946), with his outspoken support for the LNT
model, his concern about radiation, and his antipathy to Soviet ideology and
Lysenko-ism. There was no competition.
The madness of the Arms Race
In the post-war period political backing in the USA for the growth of nuclear
armaments was very strong. It was seen as the means to impress Pax
Americana on the world, and other nations, friend and foe, were very much
Illustration 36: A graph showing the number of US and Soviet
nuclear warheads deployed at different dates.
Nuclear is for Life. A Cultural Revolution 241
aware of that. Those that were able to do so reacted by developing and
deploying their own nuclear weapons. When the allies, Britain and France,
did so, it was seen as politically undesirable and a loss of security, but no
worse. However, when the Soviet Union exploded test devices, that was seen
in the USA as an existential threat.
In the intervening decades remarkably few nations have bothered with
nuclear weapons. Though they may wield influence at the conference table,
they are very expensive in technical manpower and mostly useless in the field
from a military perspective. In his work John Muller of Ohio State University
has explored why nations consider nuclear weapons such an undesirable
waste of resources [see Selected References on page 279, SR4].
Nevertheless, a few have flexed their muscles in practice (China, India,
Pakistan) or in theory (Israel, Iran, South Africa), leaving North Korea as the
only state likely to consider using a nuclear weapon in anger.
The US paranoia about nuclear weapons was exacerbated by Soviet
behaviour in taking over Eastern Europe. So was started the Cold War, as
recorded by Churchill in March 1946 [11]. As the US nuclear arsenal built up,
it was no surprise that the Soviet Union, no stranger to national paranoia, felt
threatened and joined the nuclear Arms Race (see Illustration 36). For many
years the system for delivering nuclear warheads was manned bombers,
patrolling around the clock and ready to respond to any attack. Later, these
were replaced by missile delivery, at first of limited range. But with the
launch of the first satellite, the Russian Sputnik, in 1957, came the realisation
that inter-continental rockets would be able to deliver nuclear warheads to
anywhere on Earth with minimal delay, and that the Soviet Union had the
lead in this technology. Later developments included missiles carrying
multiple warheads and missiles launched from submarines that can remain
submerged and hidden for months at a time, ever ready to deliver a revenge
counter attack should the other side mount a first strike. International politics
at this time was dominated by the tension between the USA and the Soviet
Union, said to be stabilised by the mutual fear of the consequences of nuclear
war and the balance between their arsenals. The end of the Cold War came at
a summit meeting in Iceland in 1986, coincidentally six months after the
Chernobyl accident. Although technically quite unrelated, the Soviet political
self-confidence in nuclear technology seems to have collapsed generally at
this time, and by 1991 the Soviet empire, as such, appeared to be no more.
Chronology of nuclear turning points
•16 July 1945: Trinity test of the plutonium bomb, 21 kiloton.
•6 August 1945: Uranium bomb dropped on Hiroshima.
•9 August 1945: Plutonium bomb dropped on Nagasaki.
242 Chapter 10: Science Distorted by Frightened Men
•29 August 1949: First Soviet nuclear test.
•3 October 1952: First British nuclear test.
•1 November 1952: First US hydrogen bomb test.
•1 March 1954: The voyage of the Lucky Dragon (more below).
•9 July 1955: Russell-Einstein Manifesto (more below).
•1956: Recommendation from the BEIR1 Committee that
Radiological Safety should no longer be assessed against a threshold
but using the LNT model (for reasons expanded upon later in this
chapter).
•4 October 1957: Soviet Union launch of Sputnik, the world's first
Earth-orbiting artificial satellite.
•1958: Petition to UN by Linus Pauling and others (more below).
•13 February 1960: First French nuclear test.
•17 January 1961: President Eisenhower's valedictory speech, in
which he warned of the power of the Industrial Military Complex
that had built up, distorting the free exercise and funding of much
scientific academic work in universities, as discussed further in
Radiation and Reason, Chapter 10.
•30 October 1961: Largest-ever test by Soviet Union; 50-58 megaton.
•March 1962: Letter from Linus Pauling to President Kennedy (see
page 248).
•October 1962: Cuban Missile Crisis (see page 250).
•5 August 1963: Partial Test Ban Treaty (Soviet Union, USA, UK)
banning atmospheric nuclear testing.
•11 October 1986: Meeting in Iceland between Presidents Reagan and
Gorbachev, often seen as marking the end of the Cold War.
•1988: The report of the BEIR IV Committee attempted to close the
door on evidence-based thinking, claiming as [12]
... a matter of philosophy, it is now commonly assumed that the
stochastic effects, cancer and genetic effects, are non-threshold
phenomena and the so-called non-stochastic effects are threshold
phenomena. Practical limitations imposed by statistical variation in
the outcome of experiments make the threshold-nonthreshold issue
for cancer essentially unresolvable by scientific study..
Nuclear is for Life. A Cultural Revolution 243
Because the proponents saw the question as untestable, they were not
prepared to scrutinise it.
•10 September 1996: UN Comprehensive Test Ban Treaty banning all
nuclear explosions (still not ratified by the USA).
•2004: Repudiation of the biology of the LNT model in a unanimous
joint report by the French academies of science and medicine [26].
•2007: ICRP Report 103. An excerpt from paragraph 36 indicates their
non-scientific thinking [13]:
At radiation doses below around 100 mSv in a year, the increase in
the incidence of stochastic effects is assumed by the Commission to
occur with a small probability and in proportion to the increase in
radiation dose over the background dose. Use of this so-called
linear-non-threshold (LNT) model is considered by the Commission
to be the best practical approach to managing risk from radiation
exposure and commensurate with the ‘precautionary principle’
(UNESCO, 2005). The Commission considers that the LNT model
remains a prudent basis for radiological protection at low doses and
low dose rates.
Far from being the best practical approach, as they suggest, the LNT
model has been used to justify the most inhuman response to nuclear
accidents.
Public exposure to radioactivity from weapons
Nuclear testing in the atmosphere
The radiation from weapons testing in the atmosphere was caused by the
extreme heat of the detonation carrying radioactive material high into the
stratosphere where it spread over the whole Earth and descended gradually,
giving an exposure of radioactivity at the surface known as fallout. This was
measured, and annual values in the UK are shown in Illustration 37. The
decrease after 1963, the end of atmospheric testing by the USA, Soviet Union
and UK, was due to natural depletion of atmospheric radioactivity by the
action of the weather and radioactive decay. The small blip in 1986 is the
effect of Chernobyl, evidently far smaller than the effect of weapons testing
that lasted for many years. Nevertheless, all these exposures are small, as the
scale shows: at its peak the exposure from fallout was 0.14 mGy per year.
This may be compared to the average annual natural radiation dose of less
than 2 mGy per year, and to 10 mGy from a modern diagnostic scan which is
beneficial.
244 Chapter 10: Science Distorted by Frightened Men
Much more worrying to the world population in those years were the
thousands of nuclear warheads that were stockpiled, principally by the
Soviets and the United States (see Illustration 36). These could have been
fired in semi-automatic response by a few people in error or in an ill-
considered response to an international incident resulting in worldwide
fallout on a scale a thousand times larger than testing – that is a few hundred
mGy per year. The effect of this global radiation dose would have been in
addition to that of the local blast and fire in the regions where the warheads
exploded. The need to cease adding more missiles, to cease testing and to
decommission these stockpiles was clear; it generated semi-permanent public
protest around the world with many scientists taking part. Nevertheless, few
people understood the numbers and that the dose from the testing alone was
harmless. Although the LNT claim that every dose, however small, is harmful
is not substantiated by reliable measured evidence, the belief that it would be
harmful was important in the political decision to halt the Arms Race, as will
become clear.
Anti-nuclear demonstrations in free countries
Everyone alive at the time of the Cold War may prefer to forget what it was
like, and it is seldom explained to later generations what a pall of dread hung
over every man, woman and child on Earth who could read a newspaper or
listen to the radio. The effect of a nuclear attack was seen as more than just a
remote region devastated by blast and fire – in those days everyone could still
recall the pictures and news from the total ruins that were Berlin, Hamburg
and Tokyo after WWII. A nuclear war was visualised in the media as an
escalating tit-for-tat leading to the destruction of thousands of cities, given
that the arsenals of the two sides had several tens of thousands of missiles
ready to fire (Illustration 36).
Illustration 37: A graph showing the fallout from nuclear weapon
testing (and Chernobyl 1986) as measured in the UK.
Nuclear is for Life. A Cultural Revolution 245
The result of such a nuclear exchange was seen as even worse, because of the
reported effect of the radiation from the fallout, spread far and wide around
the Earth, the combined effect of all the warheads – and lasting for centuries.
Anti-nuclear movements started at national level, first advocating nuclear
disarmament then opposition to nuclear power. They mounted large public
demonstrations, marches and occupations, in particular the famous annual
52-mile march from London to the Atomic Weapons Establishment at
Aldermaston, which was held from 1958 to 1962 and attracted many tens of
thousands of participants. The leading anti-nuclear peace movement
organisations around the world at various times – the Campaign for Nuclear
Disarmament, Greenpeace and Friends of the Earth – have attracted a large
following, including many distinguished intellectuals, church leaders and
public figures.
Mobilisation of public opinion on this scale influences political parties in a
democracy, and politicians are obliged to take note. In many countries both
nuclear energy and nuclear weapons have been made illegal. Nations that are
currently opposed to nuclear power in principle include Australia, New
Zealand and many EU countries.
Fallout in fact – The Lucky Dragon
The US test of a hydrogen bomb on the Bikini Atoll in the Pacific Ocean on 1
March 1954 was exceptional [14]. It was designed to use lithium deuteride
(LiD) as a solid fuel in which the minor component, lithium-6, provides the
tritium needed when bombarded by a neutron. It was not known before the
test that the major component, lithium-7 (92.5%), would also react with a
neutron, thereby increasing the energy released from 6 megatons to 15
megatons, the highest energy test ever detonated by the USA and nearly
1,000 times the energy of the Hiroshima or Nagasaki device. As a result, the
area that had been kept clear of shipping to avoid high levels of fallout was
far too small. Further, the fallout was particularly large because the device
was detonated at ground level, thereby creating much additional radioactive
material and propelling it into the upper atmosphere.
Most heavily contaminated by the fallout was the Daigo Fukuryu Maru, the
Lucky Dragon No. 5, a 140-ton Japanese fishing boat with a crew of 23. The
exact position of the boat at the time of the explosion is not known, but it is
thought that it was about 80 miles away. The crew suffered severe beta burns
on their skin and when they reached Japan they were treated for ARS
although, unlike those contaminated at Goiania and Chernobyl, none died of
it in the next few weeks. One crew member died after seven months of
cirrhosis of the liver – radiation is unlikely to have been the prime cause.
Like survivors of Hiroshima and Nagasaki, the crew were stigmatized
because of the Japanese public’s fear of radiation exposure, believing it to be
246 Chapter 10: Science Distorted by Frightened Men
contagious or inheritable. Another crew member reported that when the
fallout came down he had licked it to test it – in 2013 he was reported to be
alive at 79 years old. In 2014 another crew member was reported to be alive
at the age of 87. Many details are missing, but, as in other nuclear accidents,
the mortality that many had feared or expected at the time, has not been
realised [15].
The incident was a diplomatic disaster for the USA, and did nothing for the
reputation of the radiation and its safety either. As often happens, an attempt
was made to make amends by paying compensation, although litigation and
compensation muddy the water for the scientific record by persuading voices
to remain silent or change their story. But after more than 50 years we can
say that the effect on human life may have been no more than several cases of
intense beta burns, similar to sunburn in fact. However, absolutely nobody
believed that at the time, and nobody has corrected the public perception
since. No erratum ever makes a good news story.
Fallout in fiction – On the Beach
Fear of nuclear technology has stimulated 70 years of sensational
entertainment that has gripped the world. One of the most famous novels, On
the Beach by Nevile Shute published in 1957, is set in Australia where a
surviving southern outpost of life watches as the radioactive fallout, liberated
by an all-out nuclear war in the northern hemisphere, creeps gradually south,
extinguishing all signs of life as it does so. The story is thrilling, and was
made into a popular film, but the science is flawed, although that did not
prevent it making many conversions to the anti-nuclear cause; notably Helen
Caldicott who says that when she read the book as a 12-year old It scared the
hell out of me. Since then she has pursued an emotional anti-nuclear
campaign which has been heavily attacked for its fear mongering and lack of
any scientific basis [16].
No one who lived in the Cold War era could have failed to enjoy the talents
of Tom Lehrer, the American singer-songwriter, satirist, pianist, and
mathematician. Among his blacker nuclear songs was We will all go together
when we go. It was a piece with a typically jolly tune and words about total
nuclear death – the Cold War years encouraged such macabre humour. The
words nuclear and radiation have entered the popular language as scare
words, the adult equivalent of saying BOO! to a small child who then runs
away and hides [17].
There were many more expressions of nuclear gloom and horror in the arts,
but why should we make note of these here? Because we are going to need to
counter them with equal talent if we are to overcome the legacy of 70 years
of nuclear phobia. The effects of carbon fuels on our environment and our
civilisation may be the alternative. So we need to find the sons of Nevile
Nuclear is for Life. A Cultural Revolution 247
Shute, sons of Tom Lehrer, daughters of Jane Fonda, and of all those in the
arts who performed in the anti-nuclear era. New artistic talents are urgently
needed in the coming decades to reverse the message their parents and
grandparents gave so brilliantly.
Warnings from the intellectual elite
Russell-Einstein Manifesto
By 1955 it was widely felt that mankind faced an existential threat from the
nuclear powers, and with the prospect that many further nations might also
acquire such weapons, the prospects looked dire. Joseph Rotblat, the only
scientist to leave the Manhattan Project on moral grounds, remarked that he
became worried about the whole future of mankind. In the following years he
worked with Bertrand Russell, the eminent British philosopher, on efforts to
curb nuclear testing and proliferation. It became apparent that only a joint
declaration by a number of respected Nobel Laureates could hope to wield
the moral authority needed to head off the danger – although, as will become
apparent, even that was not sufficient.
The Russell-Einstein Manifesto was launched at a news conference in
London on 9 July 1955. Albert Einstein had died shortly before, but after
signing the manifesto. The other signatories were: Max Born, Percy
Bridgman, Leopold Infeld, Frederic Joliot-Curie, Hideki Yukawa, Cecil
Powell, Hermann Muller, Linus Pauling, Joseph Rotblat and Bertrand
Russell. Of the eleven, ten had won, or would win, a Nobel Prize. This is a
very distinguished list indeed, but, with the exception of Hermann Muller,
not one of them was a biologist or medical scientist.
The manifesto started by calling for a scientific conference:
In the tragic situation which confronts humanity, we feel that
scientists should assemble in conference to appraise the perils that
have arisen as a result of the development of weapons of mass
destruction
and went on:
No doubt in an H-bomb war great cities would be obliterated. But
this is one of the minor disasters that would have to be faced. If
everybody in London, New York, and Moscow were exterminated, the
world might, in the course of a few centuries, recover from the blow.
But we now know, especially since the Bikini test, that nuclear bombs
can gradually spread destruction over a very much wider area than
had been supposed.
It is stated on very good authority that a bomb can now be
248 Chapter 10: Science Distorted by Frightened Men
manufactured which will be 2,500 times as powerful as that which
destroyed Hiroshima. Such a bomb, if exploded near the ground or
under water, sends radioactive particles into the upper air. They sink
gradually and reach the surface of the earth in the form of a deadly
dust or rain. It was this dust which infected the Japanese fishermen
and their catch of fish. [reference to the Lucky Dragon]
No one knows how widely such lethal radioactive particles might be
diffused, but the best authorities are unanimous in saying that a war
with H-bombs might possibly put an end to the human race. It is
feared that if many H-bombs are used there will be universal death,
sudden only for a minority, but for the majority a slow torture of
disease and disintegration.
Many warnings have been uttered by eminent men of science and by
authorities in military strategy. None of them will say that the worst
results are certain. What they do say is that these results are possible,
and no one can be sure that they will not be realized. We have not yet
found that the views of experts on this question depend in any degree
upon their politics or prejudices. They depend only, so far as our
researches have revealed, upon the extent of the particular expert's
knowledge. We have found that the men who know most are the most
gloomy.
The scientific conference that they called became known as the Pugwash
Conference which still works today for world peace. With its co-founder, Sir
Joseph Rotblat [10], the Conference was awarded the Nobel Peace Prize in
1995.
But scientists can make mistakes, particularly if they take their eye off the
evidence. The signatories of the Russell-Einstein Manifesto did not know
whether or not the crew of the Lucky Dragon would die from the radioactive
fallout that covered them, but they assumed that they would. Today we know
that was pessimistic, although records of the fate of the crew, distorted by
litigation and compensation, are not fully available. We have more complete
and optimistic evidence from Fukushima, and also from Goiania and
Chernobyl. Except for a handful of cases, it seems that radiation is far less
injurious to life than anyone expected, even the distinguished signatories to
the Russell-Einstein Manifesto.
Linus Pauling to President Kennedy
The aim of the signatories to the manifesto was to stop the Arms Race; stop
the testing, stop the stockpiling, then get rid of the stockpiles. What happened
showed them that calling for a conference might be a good way to move
scientists, but it did not have the desired effect at the political and military
level, and so another way to tackle the problem had to be found.
Nuclear is for Life. A Cultural Revolution 249
After winning the Nobel Prize in Chemistry in 1953, Linus Pauling had
become science's most prominent activist against nuclear weapons testing. He
resolved to speak out with the backing of the wider public, and in 1958 with
his wife he presented a petition to the UN with 11,000 signatures calling for
an end to nuclear weapons. But still the testing and Arms Race continued.
The public initiatives of 1955 and 1958 had not been sufficient to create the
magnitude of radiation scare required to stop the nuclear Arms Race.
Therefore Linus Pauling and Hermann Muller, in particular, evidently felt
that they needed to raise the rhetoric another notch. The only way they
thought might be effective was to exaggerate the evidence for genetic harm to
future generations caused by radiation. There was no scientific basis for what
they claimed, and today we know that it is factually incorrect.
They realised that committees do not make radical decisions or changes of
direction – only individuals are likely to do that. To ensure success, they
needed to pin the responsibility personally on one person who could stop the
testing – and that meant President John Kennedy. Linus Pauling's letter to
Kennedy shows the strength of feeling and the lengths to which distinguished
scientists were prepared to go. It read: [18]
March 1962 Night Letter Durham NC
President John F Kennedy
Are you going to give an order that will cause you to go down in
history as one of the most immoral men of all time and one of the
greatest enemies of the human race? In a letter to the New York
Times I state that nuclear tests duplicating the Soviet 1961 test would
seriously damage over 20 million unborn children, including those
caused to have gross physical and mental defect and also the
stillbirths and embryonic, neonatal and childhood deaths from the
radioactive fission products and carbon-14. Are you going to be
guilty of this monstrous immorality, matching that of the Soviet
leaders, for the political purpose of increasing the still imposing lead
of the United States over the Soviet Union in nuclear weapons
technology? (sgd) Linus Pauling.
He could not substantiate the threatening prospect that he held out in this
letter and today we can say that he was wrong in his claims. The concerns
that he expressed were based on a political and human agenda, not science,
but once such concerns are created, in this instance about the effects of small
amounts of radiation, it is very difficult to switch attitudes back, even with
the benefit of scientific evidence. Trust is fragile.
The dangerous road chosen by Linus Pauling led to two results: firstly the
signing of the 1963 atmospheric test ban treaty; secondly the establishment of
fallacies in the public mind, and in the mind of the authorities too, about the
250 Chapter 10: Science Distorted by Frightened Men
effects of radiation on human life. The first was what he was trying to
achieve, but the second created a mindset that distorted reactions by
authorities, for instance at Fukushima. These fallacies were primarily the
responsibility of Hermann Muller, for he was the biologist, not Linus
Pauling.
A game of nuclear chicken
Cuban Missile Crisis
In a game of chicken each player prefers not to yield to the other, but the
worst possible outcome for all concerned occurs when neither player yields.
For 13 days in October 1962 the USA and the Soviet Union came closer to
full-scale nuclear war than at any time, before or since. New US missiles in
Turkey had put Moscow in range for the first time and the Soviet Union had
started constructing missile bases in Cuba, just 90 miles from the coast of the
USA. A US U-2 spy plane produced clear photographic evidence of the
missile facilities being readied in Cuba, and so a naval blockade was
established to prevent further missiles from entering Cuba. The US demanded
that the weapons already in Cuba be dismantled and shipped back to the
Soviet Union. After tense negotiations and days when the world felt it was
living on a knife edge, agreement was reached between Kennedy and
Khrushchev. The Soviet Union would dismantle its missiles in Cuba and the
US would dismantle those in Turkey and Italy – although this was not known
to the public.
It was a chilling time for everybody worldwide, and there can be no doubt
that it played a significant part in pressing the case for controlling the Arms
Race. The first result was the Partial Test Ban Treaty of 5 August 1963 that
ended the testing of weapons in the atmosphere. How much the Pauling letter
to Kennedy contributed to this development we do not know, but the
consequences of repeatedly stoking popular fears of radiation, even though
they lack a scientific base, are with us still.
Radiological protection and the use of the LNT
model
US National Academy of Sciences genetics panel
report
After the bombing of Hiroshima and Nagasaki the physical science view of
the world was in the ascendency. The power of mathematics and physics had
been demonstrated and in case of doubt its supremacy was usually accepted.
Nuclear is for Life. A Cultural Revolution 251
This obviously had a profound effect on the judgement of those with research
ambitions in biology and in other sciences. Major opportunities opened for
those able to work by importing methods and ideas from the disciplines of
mathematics and physics into biology, even if they struggled to understand
them.
The question of the effects of ionising radiation on life was an important one
for biology after WWII, and US science naturally took the lead in
establishing international standards, rather as the British had done for
maritime and geographical standards in earlier centuries. And so it was that
recommendations to the ICRP came from the Genetics Panel of the US
National Academy of Sciences, actually its Biological Effects of Atomic
(later, Ionising) Radiation Committee (BEAR 1) of which, significantly,
Herman Muller was a member.
Edward Calabrese has researched the history of what happened and found
copies of original correspondence that suggest the BEAR/BEIR committee
saw radiobiology as an appropriate vehicle to build funding for their interest
in genetics [19, 20, 21, 22, 23]. In addition, and perhaps more altruistically, there
was the Arms Race. By reporting a worst case conclusion on the negative
effects of radiation, they might achieve both goals. So it was that in 1956 the
panel recommended that the use of thresholds in radiological protection be
discontinued and the LNT model be used instead. Its conclusions were then
adopted internationally by ICRP.
Safety not fit for purpose
Because the LNT model makes the administration of risk particularly
straightforward, other areas of safety regulation have copied it, without
establishing any scientific demonstration that it is appropriate. For example,
it is assumed that any toxic chemical poses a risk in proportion to its mass,
however small the quantity and however much it is concentrated or dispersed.
But toxicity does not work like that – small quantities may be good for
health, even essential, while excess may endanger life. This was already well
understood by the physician Paracelsus in the 16th Century (see page 188).
Since BEAR1 in 1956 there have been further BEAR/BEIR reports, but none
has reversed the adherence to the LNT model, and thence to ALARA, in spite
of the overwhelming weight of evidence against it and the serious
consequences it has had around the world in human and financial terms.
Indeed, in 1988 BEIR IV dug itself further into a non-scientific position, as
quoted on page 242. A review in 2014 of the most recent BEIR report by
Calabrese and O'Conor brings the discussion up to date [24].
Fortunately, many eminent scientists and physicians are not impressed by the
wishful thinking embedded in these reports. Lauriston Taylor (1902-2004),
252 Chapter 10: Science Distorted by Frightened Men
who was a founder member of ICRP (1928) and first president of US NCRP,
spoke out expressing his disquiet in an invited lecture as early as 1980 [25].
Some passages from his lecture are quoted on page 214.
In its 2007 report ICRP condemned the use of the Collective Dose to assess
the number of deaths in a large population subjected to low doses. (The
Collective dose is the sum of all individual doses added together and
measured in man-sievert.) This was quite illogical as the ICRP committee
failed to withdraw its support for the LNT model which, on its own, provides
sufficient simple justification for the use of the Collective Dose in this way.
Internationally, there has also been support for fresh thinking, independent of
NAS. In 2004 a unanimous joint report was published by the French
Académie des Sciences (Paris) and the Académie Nationale de Médecine [26]
that set out the biological case for a complete change in the regulation of
radiation. It was highly critical of the use of LNT theory (see further
discussion in Chapter 8).
In 2014 a new informal international group of professionals, Scientists for
Accurate Radiation Information (SARI), was set up, dedicated to securing
change both for radiological safety in general and also for a more enlightened
use of radiation in health care. It posts important articles and correspondence
[27] and its members make representations for change to major committees
around the world, including UNSCEAR, NAS, NRC and the Health Physics
Society (HPS). It has also been active in spreading a positive scientific
message in Japan in collaboration with the Japanese Society for Radiation
Information (SRI) [28].
There is great resistance from an entrenched clique to any change to the
belief in LNT concepts that they have worked with all their lives. But like
alchemy, ptolemaic epicycles, astrology, Lamarckism and other
psudosciences, LNT theory is not supported by the evidence. The necessary
changes are:
•firstly, to acknowledge the crucial role of the reactive and adaptive
cellular mechanisms in protecting life from attack by radiation which
have been an essential feature of all life-forms for billions of years;
•secondly, to accept that the prime cause of cancer is immune failure
rather than the generation of mutations that are present in any case
and kept in check by the immune mechanisms;
•thirdly, to replace LNT-based safety regulations by ones based on
scientific threshold dose rates and doses;
•fourthly, to foster a corresponding reform of public attitudes towards
safety that teaches by explanatory education rather than ex cathedra
instruction issued by authority.
These are not matters for piecemeal or incremental improvements. Policy
Nuclear is for Life. A Cultural Revolution 253
should change completely and be re-based on science as soon as possible.
Notes on Chapter 10
1) Radiation and Modern Life Alan E. Waltar on Curie ISBN 9781591022503
Prometheus Books (2004)
2) The Roentgen Treatment of Acute Peritonitis and Other Infections with Mobile X-
Ray Apparatus Kelly JF and Dowell DA, Radiology 32 Issue 6 (1939)
http://pubs.rsna.org/doi/abs/10.1148/32.6.675
3) Hermann Muller's Nobel Prize Lecture
http://www.nobelprize.org/nobel_prizes/medicine/laureates/1946/muller-
lecture.html
4) Estimating Risk of Low Radiation Doses Calabrese & Connor, Rad Res (2015)
http://www.ncbi.nlm.nih.gov/pubmed/25329961
5) The Big Lie Edward Calabrese interviewed by Steven Cherry on Hermann Muller
http://spectrum.ieee.org/podcast/at-work/education/radiations-big-lie
6) A threshold exists in the dose-response relationship for somatic mutation
frequency induced by X-irradiation of Drosophila M Antosh et al, Radiat Res
161, 391 (2004) http://www.ncbi.nlm.nih.gov/pubmed/15038774
7) http://news.bbc.co.uk/onthisday/hi/dates/stories/april/15/newsid_3557000/355734
1.stm
8) http://en.wikipedia.org/wiki/Atomic_bombings_of_Hiroshima_and_Nagasaki
9) A European eye witness report of the bombing of Tokyo
http://www.eyewitnesstohistory.com/tokyo.htm
10) The first hand personal account of Sir Joseph Rotblat makes important reading
http://www.reformation.org/joseph-rothblat.html
11) Winston Churchill at Fulton, Missouri
http://history1900s.about.com/od/churchillwinston/a/Iron-Curtain.htm
12) Health Risks of Radon and Other Internally Deposited Alpha-Emitters BEIR IV
Report, National Research Council (1988) http://www.nap.edu/catalog.php?
record_id=1026 p. 177
13) Report 103: Recommendations International Commission for Radiological
Protection. ICRP 2007 http://www.icrp.org
14) The background is described in this archival account which makes reference to
the labs "rushing to develop", indicating internal competition in the Arms Race
http://nuclearweaponarchive.org/Usa/Tests/Castle.html
15) Wikipedia entry Daigo Fukuryū Maru http://en.wikipedia.org/wiki/Daigo_Fukury
%C5%AB_Maru [8 Mar 2015]
16) Helen Caldicott - "Th" Thorium documentary A video by G McDowell
https://www.youtube.com/watch?v=Qaptvhky8IQ
17) I am grateful to Sir John Polkinghorne for this enlightening analogy.
18) The telegram written in Pauling's hand is shown in Figure 2 of the paper by
Cuttler "What becomes of Nuclear Risk Assessment...." Dose Response 5, 80
(2007) http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2477701/
254 Chapter 10: Science Distorted by Frightened Men
19) Origin of the linearity no threshold (LNT) dose-response concept Calabrese EJ,
Arch Toxicol 87 1621 (2013) http://www.ncbi.nlm.nih.gov/pubmed/23887208
20) The road to linearity: why linearity at low doses became the basis for carcinogen
risk assessment. Calabrese EJ, Arch Toxicol 83 203 (2009)
http://www.ncbi.nlm.nih.gov/pubmed/19247635
21) How the US National Academy of Sciences misled the world community on
cancer risk assessment: new findings challenge historical foundations of the
linear dose response Calabrese EJ, Arch Toxicol 87 2063 (2013)
http://www.ncbi.nlm.nih.gov/pubmed/23912675
22) The Genetics Panel of the NAS BEAR I Committee (1956): epistolary evidence
suggests self-interest may have prompted an exaggeration of radiation risks that
led to the adoption of the LNT cancer risk assessment model Calabrese EJ, Arch
Toxicol 88 1631 (2014) http://www.ncbi.nlm.nih.gov/pubmed/24993953
23) On the origins of the linear no-threshold (LNT) dogma by means of untruths,
artful dodges and blind faith Calabrese EJ, Env Res 142 432 (2015)
http://dx.doi.org/10.1016/j.envres.2015.07.011
24) Estimating Risk of Low Radiation Doses Calabrese EJ and O'Connor MK, Radiat
Res 182 463 (2014) http://dx.doi.org/10.1667/RR13829.1
with subsequent discussion http://www.rrjournal.org/doi/full/10.1667/RR4029.1
and http://www.rrjournal.org/doi/full/10.1667/RR4029.2
25) Some nonscientific influences on radiation protection standards and practice.
Taylor LS The Sievert Lecture 1980. Health Physics 39: 851-874
26) Dose-effect relationships and...Tubiana, M. and Aurengo, A. Académie des
Sciences & Académie Nationale de Médecine. (2005)
http://www.researchgate.net/publication/277289357_Acadmie_des_Sciences_Aca
demy_of_Sciences-
_Acadmie_nationale_de_Mdecine_National_Academy_of_Medicine
27) SARI http://www.radiationeffects.org
28) http://www.radiationandreason.com/uploads//enc_SRIConference.jpg in 2014 and
2015. Other links on http://www.radiationandreason.com
Nuclear is for Life. A Cultural Revolution 255
Chapter 11: Natural Philosophy of Safety
Tis not unlikely, but that there may yet be invented several other
helps for the eye, at much exceeding those already found, as those do
the bare eye, such as by which we may perhaps be able to discover
living Creatures in the Moon, or other Planets, the figures of the
compounding Particles of matter, and the particular Schematisms
and Textures of Bodies.
Robert Hooke, Micrographia (1665)
Safety in the world we see
Childhood and safety 255
Stimulated by contrast 256
Predictability exploited 257
Good and bad located 258
Art and society in a wafer 259
Safety in unexpected worlds
Further reality in evolution and quantum mechanics 260
Life through the lens 260
"Curiouser and curiouser", said Alice 261
Individual and collective decisions
The importance of education and trust 262
Taboos, phobias and forbidden fruit
Altering ourselves 263
Better care for our brains 264
Notes on Chapter 11 265
Safety in the world we see
Childhood and safety
As each human being comes to life and takes up his or her ability to
think, the questions begin: Where am I? Who am I? What do I want?
Why am I here? And such questions must start to be addressed before
any sense can be made of the consequential idea of safety. In the early
years of life, while parents provide some experience with which to
build answers, safety is reduced to the security that comes with a warm
parental cuddle. But the questions continue and the answers come with
256 Chapter 11: Natural Philosophy of Safety
education through formal instruction, individual study, personal
experience and periods of reflection and mutual discussion. What kind
of answers do we find? What do they tell us about safety?
Stimulated by contrast
A serious study can be made of the many coincidences among the
fundamentals of physical science without which the universe, the solar
system, the Earth, and life as we know them would not have been possible.
That these coincidences are realised is called the Anthropic Principle.
Although it is called a principle, it is not understood at all. Students seeking a
lifetime of stimulation will be kept busy by consulting the Wikipedia entry
for the subject [1] and following the references, many written by outstanding
cosmological thinkers.
The coincidences of the biological world that enable life are less enigmatic,
since evolution has seen to it that life is tailored to its circumstances.
However, the development of humans as thinking and studying beings has
relied on one particular fortuitous coincidence.
From Earth, every now and again when the clouds part, a window opens and
the universe may be seen. Beyond the atmosphere we can see the stars and
galaxies of stars, far away and back in time to when it was only 1/40,000 of
its present age. On most planets where life might be sustainable in some
form, such a view would be permanently obscured by cloud or dust and no
such extraordinary window on the universe would ever open. If that had been
so for Earth, civilisation would not have developed as it has, and the same
sense of wonder would not have been born. Since the dawn of civilisation it
has seemed to humans that totally different rules apply to what is seen
through that window. There, even the simplest observations display a
constancy and regularity completely foreign to the Earth-bound everyday
social experience – and modern cosmic data have only reinforced this early
impression. From the earliest historic times human observers recorded these
regularities and felt challenged to explain them.
This cosmic view has no connection to earthly success or failure, to life or
death, to love or hate, but its constancy has been seen as a model for justice
in our disturbingly chaotic social world, indeed for much that we seek in
everyday life, but seldom find. The cosmos became the model for the divine,
for a supreme being, for religion in its various forms. Among earthly
creatures only man was able to appreciate this cosmic constancy and his
special relationship to it gave him confidence and superiority, even if life on
Earth in its other aspects was played apparently without rules and caused
great irrational suffering from time to time. The environment close at hand, in
particular the weather and even the seasons, proved unreliable and
Nuclear is for Life. A Cultural Revolution 257
unpredictable, including the cloud cover that intruded between man and his
sight of the heavens. This fluctuating and unreliable environment gave little
comfort to early man and he wrestled in a vain attempt to rationalise and
prevent it endangering his life and that of his family.
Predictability exploited
Human's unique intelligence allowed us to stumble our way towards a better
life and to improve the reliability of the world around us, and its
predictability became more apparent as our studies slowly revealed how our
surroundings worked, more like the cosmos than first appeared. Improving
our standard of living was relatively objective, much of it related to physical
science and mathematics, but study of our own being and biological science
proved more enigmatic.
In the course of normal biological activity any change of circumstances can
present a threat to life, so to survive such a challenge successfully in nature,
life tests out many accessible responses, by random trial and error, to reach a
viable solution. This basic evolutionary process described by Darwin is not a
purpose-driven or cognitive search strategy. Indeed the wasted effort, the loss
of individual life and the suffering encountered during this search are
certainly not beneficial to the individuals involved. From their point of view,
at least, any strategy of change that minimises the risk of personal injury
would be seen as good. An organism that has the benefit of a developed
central nervous system and brain can record its experiences and from them
learn to improve its survival strategy. In its simplest form this additional
facility is available to many creatures and gives them substantial advantage in
the competition to survive. The larger the brain the more effectively an
animal can compare its current situation to its past experiences. This is
especially true for mankind. So an individual can recall patterns of
experience and so predict the consequences of any development or course of
action, and he or she may then make a choice that minimises pain and
suffering. So predictability is necessary for safety, but the ability to think and
understand is needed too.
That the world is ever predictable is itself quite unexplained. It could so
easily be otherwise. A waking experience of an uneducated mind – or of an
educated one in a dream – should be quite enough to show that the world
could be unpredictable – possibly haunted and malicious, subject to whims of
the imagination. But when predictability is harnessed by education and
science, real danger can be avoided with some confidence and this is the
proper basis of safety. It should be distinguished from an ersatz version of
'safety' that is laid down as a set of rules to be obeyed regardless of
understanding; this brings order through coercion but no real confidence.
Real safety depends on the education and experience of an individual who
258 Chapter 11: Natural Philosophy of Safety
can then make reliable judgements. The principle applies to the safe
interaction of an individual with other humans, just as much as his interaction
with the physical world and other forms of life. Reliability and predictability
are the essence of trust and good personal relationships, and the same is true
in wider society all the way up to the level of international behaviour.
Good and bad located
In his inanimate world man first found the predictability that he sought in the
sky – the Sun, Moon, planets and stars. He was fascinated to find that their
motion was even more regular and predictable than he suspected, quite unlike
anything else in his seemingly unpredictable and dangerous environment on
the Earth. The experience taught him to be mathematical and scientific, a
skill that he has applied in recent centuries to much of the rest of his
observations of the physical world. But this experience of the celestial sphere
was always the archetype and a model for good. Naturally, heaven, the seat of
all that is good and reliable, came to be seen as up there with God as its
personification. Unfortunately misunderstanding of this personification has
caused much trouble in the history of the world, but there is no reason why it
should have done so.
If we found that the world above our heads was reassuring, what was our
experience of other directions? A warning cry Look out! brings a reaction to
look forward, to the left and right, and then behind. The eyes and ears of
animals and birds are positioned on the front or sides of their heads, like ours.
Why is that? Sources of danger usually come from these directions. Only as
an afterthought do we look upwards in case something threatens from above,
and we seldom look down: the last direction worth looking for an impending
attack. So a sense of direction has become part of the most basic experience
that enhances our ability to survive – of safety, in fact.
Beneath our feet nothing is to be seen – all is hidden, and in this direction our
ability to detect an approaching danger has not advanced much since the days
of early man. Today we may understand the basic general mechanisms of the
inner workings of the Earth, but we are nowhere near being able to predict
when these forces might be unleashed – and the earthquake and tsunami of 11
March 2011 were a demonstration of that. Much of the time the earth is
almost totally quiet, but when it does move, great fissures may open up, rocks
tumble and otherwise solid structures shake with a terrible noise. Volcanoes
may spit sulphurous fumes, fire and great boulders fly high into the air – they
may spill rivers of molten rock down mountainsides. And, while we have
learnt where these eruptions are likely to occur, their ferocity and
unpredictability are extraordinary. No imagination is needed to see that early
man would get the message – unpredictability and evil are down there in hell,
a place of consuming fire, often personified as the Devil. This divide, the
Nuclear is for Life. A Cultural Revolution 259
polarisation between hell and heaven, was an early element of basic human
culture. Never mind the Higgs Boson and the Big Bang, physical science has
some unfinished business improving the predictability of the material world
just below our feet.
But we also experience other quite distinct theatres of existence that play to
seemingly separate rules. There is the close-by here of everyday life –
somewhere between heaven and hell, between the apparent predictability of
the stars, and the capricious and wayward destruction of the volcanic Earth.
Here are plants and animals, friends and enemies, love and war.
The success of science has spread its predictability into many aspects of life
on Earth and rolled back the fear of most natural forces, bringing a harmony
and ease to life that those living in earlier times would not recognise.
However, the success has not been complete. Science still struggles to predict
the weather reliably and to understand long-term influences on the climate.
But it has clarified many phenomena such as light, mechanics and electricity,
so reducing the scope of the unpredictable and frightening.
That leaves the task of telling more people about it: many are still unaware
that hell has retreated and that, if they were to study with care and attention,
many worries would be assuaged. To a scientist it seems odd that everybody
should not choose to study as much science as they can, for it brings
reassurance and confidence that is otherwise not available. This failure of
education persists in part because science and the necessary mathematics are
thought to be difficult. This is worth challenging and the challenge pays off,
as I have seen as a teacher over many years.
Art and society in a wafer
Within the thin shell of the Earth's atmosphere, a tiny region indeed, the
world of human society appears self-contained as it encompasses all daily
concerns for many people. This existence is portrayed in every popular novel,
film and other art forms too. The range of absorbing experiences is driven by
competition and money, ambitions and strivings; all the concerns of love and
hate, confidence and laziness, honour and disgrace, death, hope, loyalty and
many fine and enriching sensations are here, along with suffering and failure.
In this society actions have purpose, some objects are beautiful but others
ugly, some relationships are simple but many are unfathomably convoluted
and complicated. As for centuries past, everything that most people
experience in their social existence lies in this wafer. Science shows how this
existence is very vulnerable to changing circumstances, and geological
evidence confirms that such life-threatening changes have occurred not
infrequently in the past. Most are not avoidable but there are others over
which civilisation may have some influence – like surviving them, reducing
them, or even not triggering them.
260 Chapter 11: Natural Philosophy of Safety
Safety in unexpected worlds
Further reality in evolution and quantum mechanics
But in addition to the world we see, up, down and around, there are other
forms of existence that affect our lives. Few people choose to explore as
Alice Liddell did when she stepped Through the Looking Glass and down the
rabbit hole into Wonderland. If they did, they would find not just one but two
further worlds, reached through scientific curiosity, education and adventure,
each with its own topsy-turvy way of explaining and discussing existence.
And like the characters that Alice met in her adventures, they have an
unshakeable confidence in their own logic, which appears quite weird to
those not familiar with them.
There is the world of biology with its cells and evolutionary logic: its subject
is life, here and now, including ourselves. If it is realised anywhere else in the
universe, it is likely to be radically different. But then there is the world of
quantum physics, absolutely universal and all pervasive on every scale in
space and time, although some of its most striking consequences are evident
in the atom with its central nucleus. This quantum physics is a layer of
existence where the rules of logic and description are totally unlike those of
either the familiar world or biology. But understanding and working with
these two worlds and how they fit together increases predictability and safety
and therefore the confidence on which the viability of human civilisation and
its economy depends.
Life through the lens
The invention of the telescope and microscope in the sixteenth and
seventeenth centuries increased the range of what could be seen. An early
leader in the field was Robert Hooke (1635-1703) who published his seminal
book, Micrographia, in 1665. The quotation given at the head of this chapter
is his prescient view of the development of modern science and technology,
written 350 years ago. Although the invention of the telescope expanded the
view of the heavens by a vast factor, it did not really introduce a fresh theatre
of existence. However, the microscope introduced the beginning of
something quite new, the biological basis of life and its cellular structure. The
typical cells of life can just be seen under a simple microscope, as first
described and illustrated by Hooke in extraordinary detail in his book:
I ... found that there were usually about threescore of these small
Cells placed end-ways in the eighteenth part of an Inch in length,
whence I concluded there must be neer eleven hundred of them, or
somewhat more then a thousand in the length of an Inch, and
therefore in a square Inch above a Million, or 1166400. and in a
Cubick Inch, above twelve hundred Millions, or 1259712000. a thing
Nuclear is for Life. A Cultural Revolution 261
almost incredible, did not our Microscope assure us of it by ocular
demonstration; nay, did it not discover to us the pores of a body,
which were they diaphragm'd, like those of Cork, would afford us in
one Cubick Inch, more then ten times as many little Cells, as is
evident in several charr'd Vegetables; so prodigiously curious are the
works of Nature, that even these conspicuous pores of bodies, which
seem to be the channels or pipes through which the Succus nutritius,
or natural juices of Vegetables are convey'd, and seem to correspond
to the veins, arteries and other Vessels in sensible creatures, that
these pores I say, which seem to be the Vessels of nutrition to the
vastest body in the World, are yet so exceeding small, that the Atoms
which Epicurus fancy'd would go neer to prove too bigg to enter
them, much more to constitute a fluid body in them. And how
infinitely smaller then must be the Vessels of a Mite, or the pores of
one of those little Vegetables I have discovered to grow on the back-
side of a Rose-leaf.
In the following centuries, as the study of biology by Darwin and others
developed, the microscope revealed more of a world where the standards of
behaviour prized in the social world count for nothing. In the cellular world,
as for whole biological organisms, competition rules, leaving little room for
altruism and morality. Individuals are sacrificed to optimise the survival of
the species in the competition with other species. Fairness and equality of
opportunity carry no weight, neither does simplicity. Indeed, by exploring a
myriad of possibilities the selected response often turns out to be highly
evolved and far from obvious. The test for a response that is right is that it
should work effectively, but there may be many such correct possibilities,
each ensuring survival in a particular environment. Each is local to the
conditions at a point in space and time – there is no likelihood, even if life
exists elsewhere in the universe, that the particular realisations of life that we
are familiar with would have any viability elsewhere.
"Curiouser and curiouser", said Alice
Since the end of the nineteenth century the study of the structure and
behaviour of matter has penetrated to a scale far deeper than biology.
Biological cells are 100,000 times smaller than a metre; the atomic scale is
100,000 times smaller than that and the nuclear scale 100,000 times smaller
again. The atomic and nuclear scales have much in common; there the norms
of behaviour, that is of cause and effect, seem weird to a human mind
familiar with the social or biological world. This is the quantum world. When
first met, it seems confusing, but with some experience it is seen to be
decidedly simpler than the conventional or classical world. The rules in the
quantum world are extremely precise, even though they generally determine
(precisely) the probabilities of what might happen, rather than what actually
262 Chapter 11: Natural Philosophy of Safety
does. Having said that, the quantum world is not too hard to explain: it just
seems totally different from what we all learnt on mother's knee as we
stretched out with eye-and-hand coordination to grab the biscuit offered to us.
The quantum world is always correct and has no exceptions – the familiar
classical world is just a convenient approximation. Although he contributed
to it in many important ways, Einstein never really believed that quantum
mechanics was correct, but it has been giving the right answers for 90 years
now, and most theoretical physicists today think that Einstein was wrong and
that the quantum world is here to stay.
Curiously, the way that larger objects behave turns out to be identical in both
the familiar classical and quantum pictures, and in the rare cases that they
differ, it is the quantum picture that fits with what is seen when we do an
experiment. This is not a book about quantum theory, but here is one simple
everyday example, as an illustration. When we turn on an electric light, a
stream of electrons (which are solid components of ordinary matter like any
other) comes sliding through the solid copper wires that join the switch to the
electricity generator station. They do this with very little resistance, slowed
only by the fine wire of the lamp filament (or equivalent in a more modern
bulb), where they deliver up their energy as light. It seems a nonsensical idea
that the electrons should pass through the solid copper without hitting
anything, but a precise understanding of why this is expected was just the
first step in the development of electronics. Quantum mechanics is not just
descriptive, but provides the calculated basis of all lasers and modern
electronics that form the heart of much of today's prosperity – involving
business, employment and all that follows. More people need to understand it
if we are not to be left at the mercy of a small band of high priests in the
matter.
Individual and collective decisions
The importance of education and trust
It is not realistic to suppose that everybody in society should understand
everything. But there is a minimal level of education and professional
knowledge required if the citizens of a healthy society are to be able to make
decisions by consent. Just having experts in each discipline is not sufficient.
A few citizens, at least, should fully appreciate the overlap of these areas, so
that they can speak to the issues that arise when several disciplines are
involved – for instance, nuclear, biology or medicine. Without such overlaps
of individual knowledge the trust that is essential to society will be lacking
and democratic decision-making will be at risk. The greatest leaps forward in
the condition of mankind have occurred at the boundaries between
disciplines. Conversely, the Dark Ages, a period of misunderstanding and
narrow prescriptive education, coincided with deprivation and economic hard
Nuclear is for Life. A Cultural Revolution 263
times.
The most effective integration of ideas is achieved initially in the mind of a
single person. In this respect narrow specialised education is unhelpful,
because it is unlikely to contribute balanced judgements between disparate
alternatives. The use of specialised expert opinions inhibits the emergence of
a melded view, because experts tend to be possessive and confident about
their own narrow fields, while naturally cautious of matters beyond their
personal knowledge. Consequently, nobody is in a position to take the far-
reaching interdisciplinary decisions, or worse, such decisions are taken
managerially or politically without technical understanding and simply on the
basis of conflated expert views. A conference or a committee leads naturally
to consensus, the least unacceptable conclusion, rather than a far-reaching
innovation. Unfortunately, in many modern societies enthusiasm for
specialised education is the norm, and many decisions are taken by
politicians after expensive expert enquiries. But such experts have their own
vested interest in building the exclusivity of their advice, often through
emphasising how difficult and demanding their speciality is. What is needed
is an overarching view that explains the simplest and most comprehensible
solution. On interdisciplinary matters like nuclear power and radiation safety
the wrong conclusions have too often been reached – but almost nobody
realises that. Here, wrong usually means unnecessary, unscientific and
expensive, but designed to achieve legal protection. When conveyed to
society at large, decisions reached in this way are defended on the basis that
knowledgeable opinion has been consulted and a consensus has been
reached. Not surprisingly, society is not always impressed and speculates
whether other motives are at work. Issues may be seen as more political than
scientific, while those involved hide behind the defence that proper
procedures were followed. In a 1966 talk to high-school science teachers
Richard Feynman famously said
Science is the belief in the ignorance of experts.
It was a provocative remark and many have been successfully provoked by it:
it implies that experts should be more thoroughly cross-examined. That is
only possible with more interdisciplinary education – more people to ask the
questions and to understand the answers critically.
Taboos, phobias and forbidden fruit
Altering ourselves
So nuclear radiation should be taken off a list of taboos. If it is treated with
care and kept isolated in the right place, we do not need to worry about it so
much – similar to our attitude to high explosives or rat poison, for example.
264 Chapter 11: Natural Philosophy of Safety
But what is left by way of forbidden fruit? Are there other items on a list of
taboos whose credentials we might usefully question?
In Chapter 10 we referred to the subject of eugenics, the study of human
breeding to improve mankind's own stock. From the late nineteenth to the
mid twentieth centuries this was a taboo discussed by Hermann Muller and
others, but finally put beyond the bounds of the acceptable by the
experimental activities of Dr Mengele during the Nazi regime. Since then, the
technical possibilities have grown with the understanding of genetics and the
decoding of DNA. The subject is still taboo, but what are we afraid of? If
genetic modification is likely to give unpredictable consequences, that is
certainly reason to shun it. But is that the situation now?
In the UK, as a result of good communication, there has been public and
government approval for the 2015 application to permit the exchange of
mitochondrial DNA, thereby correcting certain genetic disorders. This is not
actually genetic modification, but the public issues are similar and it
demonstrates what can be done if taboos and phobias are set aside and
replaced by proper democratic discussion. As the effect of genetic
engineering becomes more predictable and reliable, society should have the
confidence to decide what is for the best, a step at a time.
The modification and improvement of crops is with us. Do we accept
genetically modified food? We need to ensure enough genetic diversity, so
that not all our eggs end up in one basket, so to speak. Lack of diversity
would open our supplies to attack by a single specific virus or bacterium, and
this is already a cause for some concern. Independent biologists rather than
commercial interests should answer questions and educate the public at large,
including children. We should move forward slowly, but simply saying no on
principle, as some do, is short-sighted. The taboo of genetic modification
should fade away, but we shall see whether public education is able to come
to the rescue.
And the same with nuclear-phobia. There is a precedent for moving public
policy that should make us pause. As described in Chapter 10, indiscriminate
use of the fear of radiation was used to halt the Arms Race. Indiscriminate
use of the fear of climate change should not be used to override radiation
phobia. Radiation phobia should be dismissed on its own de-merits, even if
climate change encourages us to get the right answers.
Better care for our brains
The fears that we do not have could be as important in the future as those
issues on which we lavish undue caution. For example, changing the way we
use our brains is not subject to taboos. Mind-altering drugs and alcohol are
tolerated – at least they are not the subject of as much fear as they deserve to
Nuclear is for Life. A Cultural Revolution 265
be, perhaps because any effects are not inheritable. In any case, many of them
are not new on the scene. But computers and smart-phones are, and they
already invade our personalities and how we communicate and interact. As
yet, there is no knowledge of their effects on the organisation of the user's
brain and so no idea of any safety requirement that should be applied. This is
surprising – a mind that does not need to think hard, will soon become slow
and out of condition, like the body. This cannot be healthy. What sort of
accident might trigger public awareness of this question? For that matter,
what development might motivate more medical work on such questions?
Soon, it is likely that electronic real-time surveillance of our health – what
our bodies are doing – will be taken over by digital technology in a similar
way. Some developments will be beneficial, others will lead to damaging
addiction, but the lack of open public discussion of new developments seems
ill-judged. Should we not exercise more caution about the invasion of our
innermost thoughts by silicon?
Notes on Chapter 11
1) Wikipedia Anthropic Principle.
Nuclear is for Life. A Cultural Revolution 267
Chapter 12: Life without Dragons
Cheap and abundant nuclear energy is no longer a luxury; it will
eventually be a necessity for the maintenance of the human condition
Alvin Weinberg
Evidence and communication
Selecting sources 267
Personal and professional voices 268
What has happened
Public confidence lost by neglecting education 270
Climate change and the environment 270
Stability and influence in a society
Effect of runaway fears and fashions 271
Social contract for safety and stability 272
The way ahead
New safety standards 273
Enlightened education for the twenty-first century 274
Deployment of nuclear technology 275
Advances in radiobiology and clinical medicine 275
Working for the world or cleaning up 276
Professional initiatives 278
Notes on Chapter 12 280
Evidence and communication
Selecting sources
In these chapters we have followed most of the major developments that have
shaped views of the effect of radiation on health – Hiroshima and Nagasaki,
the fishing boat Lucky Dragon, Chernobyl, Goiania, Fukushima and the
experience of a century of using moderate and high radiation doses in clinical
medicine to save lives. There are the accounts of research with mice and dogs
who have received lifelong doses and doses at critical reproductive stages.
All of these fit the picture of modern radiobiology, in which life has evolved
268 Chapter 12: Life without Dragons
over thousands of millions of years specifically to cope with the dangers
posed by oxygen and ionising radiation.
But there are many other results that have been omitted with smaller radiation
doses, or a smaller number of people where the conclusions seem less certain.
Often these are published and then reported in the press as showing that such-
and-such might cause cancer, sometimes quoting a confidence level like 95%,
which may sound rather convincing. But a 95% confidence level means that
1 in 20 such results should be wrong on average, and, further, if the
experimenters made a few choices of how to analyse the data that emphasised
their result – it can happen almost without realising it – the chance of getting
the wrong answer can easily rise to 50% or more. In many sciences such
results get rejected by referees and are not published. But it would be too
much to ask the reader to follow detailed statistical arguments to expose such
fallacies here. Fortunately, that is avoidable; if a similar investigation has
been carried out with a larger dose or more subjects and no effect of the
radiation has been found, then any effect apparent for the smaller, less certain
experiment definitely is mistaken. This is why we have chosen the larger or
higher-dose experiments, and ignored the others. So, for example, there is no
discussion of child leukaemia in the neighbourhood of nuclear plants. The
studies that claim there is such an effect involve doses that are very much
smaller, even than the natural variation of the background dose from rocks
and cosmic rays [1].
Personal and professional voices
It is curious how those in Japan professionally qualified to speak out have
been reluctant to do so. As Jerry Cuttler has remarked:
It's so ironic that so much of the best research in radiobiology has
been carried out in Japan and the essence of this work has not been
communicated to the political leaders of Japan.
We have not simply followed the opinions of individuals or authorities. These
are often strident and emotional, and it is more scientific to look directly at
the data that they have access to. However, the personal testimony of an
evacuee is a primary source. The following was written two years after the
accident, 10 March 2013: [2]
...these young people, these households with children, will not
contemplate going home, they think not of returning to the village,
nor will they until the radiation level is below world standards, and it
is possible to live safely, with a sense of security, living off the fruits
of the land – until that happens, I think it is only natural to stay away
from the village, and as a parent of children myself that is the best I
can hope for. To avoid having to shut up our children and
grandchildren indoors. That seems to be something that the officials,
Nuclear is for Life. A Cultural Revolution 269
cabinet ministers and bureaucrats in the capital cannot apprehend.
And as a matter of fact, although our village was a high-level
radiation zone, we accepted evacuees from Minami-Soma and some
of those from Namie whose escape had been delayed, and in each of
the village’s twenty hamlets, we prepared food for those evacuees,
thinking it was aid, but we fed them irradiated food, and
unnecessarily increased their dose of internal radiation. The
possibility of internal radiation poisoning implies heavy
responsibility. We meant well .... We who gave them the emergency
supplies are full of remorse that we knew not of the danger in what
we were doing, and we pray from the bottom of our hearts that no
harm to health will result.
Nobody seems to have given the public reply that such feelings deserve. A
message of unqualified reassurance should have been given – there was no
disaster that endangered life at the Fukushima accident.
But who should give this public message? Few people have attempted to
explain the reassuring facts to the public and the press prefer to stick with the
prevailing view, as they see it. Committees do not readily change their
opinions – only individuals are able to do that. Unfortunately, many authors
who have written on the subject, even recently, have preferred to persist with
the ALARA story instead of examining the evidence [3]. The legacy of 70
years of accepted phobia is a barrier so high and nuclear energy is so
inhibiting that writers avoid answering the searching questions. Nobody
dares to stick their neck out and say what everyone must know. Take a bow,
Hans Christian Andersen – you got the story absolutely right! We all know
what happened to the Emperor's courtiers, but have not considered that the
same might apply to us personally.
So it is still true, in spite of the medical evidence, that patients receiving X-
ray scans are told by the IAEA: [4]
The risk for radiation induced cancer is low but additive. Each
examination the patient undergoes slightly increases the risk.
Keeping patient doses minimum while getting images of adequate
diagnostic quality is therefore recommended. The probability for
radiation induced cancer increases by 5-6% for every 1000 mSv of
dose. Cancer risk increase arising from most examinations is
relatively small as compared with the risk of naturally occurring
cancer which ranges between 14% and 40%.
However, this is a line with which many medical professionals around the
world profoundly disagree [5]. Risks from radiation are not cumulative as
stated.
People are reluctant openly to acknowledge this message about the safety of
270 Chapter 12: Life without Dragons
radiation, perhaps because its scope stretches beyond the expertise of each
individual or the remit of any one committee. An article submitted in
response to a request by the UK House of Commons Science and Technology
Select Committee in 2011 was posted, but its message was ignored [see
Selected References on page 279, SR9], as also have been some presentations
to the press [6]. Yet the uncommitted public and the younger generations are
interested to hear because it is a story that they have never been told before,
and they eagerly ask questions [7]. Authorities in the nuclear industry have
their own longer standing views and commitments.
What has happened
Public confidence lost by neglecting education
For many people, for as long as they can recall, the situation seemed clear –
nuclear energy is dangerous, unpopular and simply avoidable – or so it
appeared until doubts arose about the use of carbon fuels. They may still be
alarmed by the possibility of deadly radiation from nuclear weapons of mass
destruction (WMD), and such views, taken as scientific facts, are used by
unscrupulous world leaders to influence political decisions and echoed in the
media without question. Nobody has explained the scientific evidence to the
public at large, and the public has stopped asking questions. Decades ago
they lost interest and trust in voices that spoke in favour of nuclear energy. As
a result many investors in nuclear technology reached the conclusion that the
best financial returns are in contracts to decommission plants, dispose of
waste and decontaminate land. In these cases the nuclear industry has been its
own worst enemy – it has not spoken out when cornered by unscientific
regulations that have driven up costs and inflated the nuclear safety bubble.
This bubble will implode when safety is returned to a scientific basis and
costs are halved. Only restrictive regulations – and the perceived self-interest
of some third parties – stand in the way of realising carbon-free energy that is
completely safe and far cheaper [8].
Climate change and the environment
The world's expanding appetite for energy, the extra emissions involved and
the evidence for a changing climate are now changing opinions too. If
nuclear energy is shown to be both safe and necessary as the only reasonable
base-load carbon-free supply, then sooner or later public opinion will demand
changes in policy. Although there are different attitudes to radiation in each
nation, with the authorities treating safety questions as matters for local
decision, the public view of the threats to the environment is more universal,
especially among the younger generation. The incomplete solution offered by
renewables makes the case for nuclear energy more urgent. The experience of
Nuclear is for Life. A Cultural Revolution 271
the French and Canadian electricity utilities has shown that carbon could be
almost eliminated from base-load supply with nuclear energy. With the
growth in electric rail and road transport, major carbon reductions are
possible. This would not halt climate change or the related release of methane
by the melting of the permafrost, but it should be the best mitigating solution
available.
Regimes such as those in Russia and China are continuing to invest in
nuclear power plants, not only in their own countries, but in client countries
around the world with less nuclear know-how. In democracies these
developments have not been heeded, but only those sections of their
industries which participate in building, investing and exporting can hope to
avoid being left behind. A lack of know-how and ownership of nuclear
energy supply form a threat to future competitiveness that many democracies
seem to have ignored.
In the short term work continues to appease public opinion by investing large
sums to make even safer the nuclear plant that has already been shown to be
safe, or to decommission it without good reason while burning carbon fuels
instead. In the medium term the bubble of this activity will burst as soon as
the public learns how the costs are inflating the price of electricity to them
and to industry, without benefit. The nuclear industry, rather than working to
unnecessary standards on waste and decommissioning, would be more
gainfully employed if it were encouraged to build the extra nuclear plant that
is needed now.
Stability and influence in a society
Effect of runaway fears and fashions
In Chapter 3 we referred to the competition between many individuals that
enables a population to survive; this is like the relationship between cells
within an individual that helps that individual to survive. The parallel can be
taken a step further by likening a society to an organism. A society is an
evolutionary product of the circumstances in which it finds itself. It reacts
and changes according to the challenges that impinge on it from time to time.
It has structure – laws, education, traditions, rights and duties – that it applies
to its members, and other norms that it applies externally to others. Its
survival depends critically on whether these reactions are fit for purpose – if
they fail to support its members, the society as a whole risks being invaded,
economically, culturally or militarily. If it is swallowed up in some way, it
loses its identity to another.
It is a moot point whether society thinks and acts effectively with purpose in
anticipation of attacks upon it – that is a supposition, but does it happen?
272 Chapter 12: Life without Dragons
Large sections of most societies behave reactively in pursuit of individual and
personal objectives only, and an effective society is one that is able to
channel such self-centred ambition to the good of the society as a whole.
Many activities within the society are benign, even if they are not motivated
by the common good. However there are others that increasingly drain the
resources of the society, and cause public opinion to polarise in support of an
irrational objective. These behave like malignant tumours, weakening the
society and making it more likely to fall foul of some different hazard or
suffer a steep decline in fortune.
Runaway inflation is an example, and a housing bubble with a building spree
is another. Then the imperative is to do what everyone else is doing with all
possible speed. This drives instability and leads to disastrous results. An
irrational horror of radiation is a further example. The cost to the Japanese
economy of keeping 50 reactors on stand-by and substituting fossil fuel is
30,000 million dollars per year [9]. The costs of the German policy of closing
all their reactors by 2022 is less easy to read since about half continue,
weighed down by extraordinary taxes.
When the irrational fear of nuclear energy spreads to a copy-cat fear of
mobile phone masts and electricity pylons, because the label radiation is used
in their description, then the disease has metastasised, like a cancer, and is
liable to infect the perception of any application of modern science.
Social contract for safety and stability
In a society the people may contract to uphold the stability of the society in
exchange for the safety that it can provide and for the personal freedom to
bargain for the resources to satisfy their reasonable needs for food and
shelter. The people also need employment to earn money and fulfil their side
of the contract. Either by paying through taxation or by paying directly,
people should be able to buy education to optimise their employment, present
or future; and in a similar way they need access to health care.
If people are dissatisfied with their contract, the stability of society is at risk.
Unemployment and inadequate education are likely causes; so too are disease
and ill health. But controlling people through rules and laws does not add to
motivation in the way that understanding does; the contribution of rules to
stability is authoritarian, while understanding brings resilience and inbuilt
assent. Education boosts confidence and provides an understanding of safety,
without which it is no more than a set of rules to be obeyed.
Education makes democracy possible, because the people can then
understand the issues. Over the decades, as science and technology have
moved forward, the education level needed for a stable democracy has risen.
Insofar as citizens have decided to turn their backs on any understanding of
Nuclear is for Life. A Cultural Revolution 273
science, democratic opinion has become uninformed and a source of
instability.
Motivating people by regulation is less effective than by understanding, but
what use can be made of money? Society can control behaviour with money
more flexibly than with law. Instead of outlawing waste or litter, we could
cost it according to whether it is hazardous. More generally cost would relate
to availability, as well as the related enhancement of life or risk of death. This
is a childish economic model, but we may learn a little by sketching it.
Discharging biological waste would be very expensive. Many would never be
able to pay, but this flags up the difficulties of this type of solution. Dumped
chemical waste, and any form of carbon burning would be expensive, too,
because of the effect on the environment. Fresh water should be expensive, as
it is essential and often in seriously short supply. Penalising long-distance
travel would cut the spread of diseases and encourage the substitution of
electronic communication, which should be free. By these criteria nuclear
waste would not be very costly, given that in quantity it is a millionth of
fossil-fuel waste per unit of electrical energy, it would have no effect on the
environment and would be recycled leaving only the small amount of
unusable fission waste to be buried. But what about energy itself? To the
extent that it is emission-free it ought to be free at source – energy, too cheap
to meter, at last [8]. These suggestions may not currently be feasible but they
indicate the direction in which to move.
The way ahead
New safety standards
Natural radioactive decay heats the Earth and drives tectonic plates,
earthquakes and tsunami, creating the real disaster of March 2011 in Japan.
The radioactive decay heat of the reactors at Fukushima, a contained local
problem, harmed no one and was not a disaster at all. For years scientific
opinion has stood by and watched while antinuclear-inspired political fear
has run riot, wasting enormous resources and diverting attention from the real
global threats to civilisation: socio-economic stability, environmental change,
population, food and fresh water. Science should speak, and should have
spoken earlier.
Science, not the result of litigation or a popular political vote, is the only firm
basis for radiological safety and genuine reassurance. The international
authorities (ICRP, UNSCEAR and IAEA) should change the philosophy of
their recommendations to relate to real dangers, which would ensure that the
world does not continue to be spooked by the one major energy source that
could support future socio-economic stability without damage to the
274 Chapter 12: Life without Dragons
environment. They should discard the use of the LNT idea altogether and
replace it by the use of thresholds. The science base of the LNT model has
been shown to be bogus and incompatible with modern biological science; its
predictions do not fit the evidence.
Today it is known that there is no substantial risk for an acute dose less than
100 mGy, nor for chronic dose rates of less than 100 mGy per month. This
turns out to be close to the threshold equivalent to 60 mGy per month set by
ICRP in 1934. The maximum risk-free lifelong dose is not completely clear,
but present evidence suggests that it is at least 5,000 mGy. These thresholds
are arguable to factors of two or three, but, used in place of the fearful
ALARA/LNT regulations, they should reduce social stress and defuse the
exaggerated concerns and expense related to waste and decommissioning. In
this way the public would be relieved of the excessive utility charges that
arise from irrational regulations that do not contribute to safety in any way.
Equally they should be reassured that any diagnostic radiation scans that
might be recommended are without any risk of cancer (up to about 10 per
month) and their radiologists should be similarly reassured.
A fresh international outlook is needed that concentrates on climate, the
environment and scientific education which includes radiation, biology and
nuclear science. Current committees with an obsession for nuclear safety
should be replaced by new ones with a remit to engage with actual risks
instead of hypothetical ones.
Enlightened education for the twenty-first century
Programmes are needed to educate the public and explain how ionising
radiation benefits everybody through medicine, carbon-free power,
desalination and food preservation. To build trust this education should best
come not from government or industry but through medical, university and
school teachers, free of any suggestion of vested interest. A vital first step is
to ensure that these teachers themselves are up to speed. Education takes time
because it has to spread out from its sources. But social media and the press
can speed this process. When informed and motivated, the press can spread
understanding and confidence about science that may determine whether
civilisation survives the coming challenges. The easy ignorance and
reluctance to investigate that have blighted press-reporting of the nuclear
story should not be accepted or continue – and the same applies to GM crops
and other demanding matters on which our future depends. Still, the main
thrust of education should come through schools and universities. This calls
for worldwide support from disinterested academic bodies and philanthropic
foundations, as well as national governments.
Nuclear is for Life. A Cultural Revolution 275
Deployment of nuclear technology
It is already late to benefit the environment by converting static power
generation provided by carbon fuels to nuclear, but it should be done with
minimal further delay. Nuclear plants that are idle should be restarted; further
questions should be asked about those that have recently been closed on
economic or safety grounds – judgements of the finance and the safety of
nuclear power are suspect.
In the short term, new power plants should be built to available designs.
Which design should be preferred is a commercial decision, but any such
decision should be eased, planning and building times reduced and final costs
lowered, with a proper relaxation of the present obsession with safety.
In the medium and longer term, fast-neutron reactors should be used to close
the fuel cycle. This is not a new possibility, although there are a number of
competing designs – earlier ones available now and newer ones that require
further development. Some designs are said to be safer, but what is important
is the higher rates of fuel burn-up, the ability to use recycled fuel from light-
water uranium plants, redundant weapon fuel, plutonium, thorium, and
depleted uranium [10]. With recycling and current reserves of uranium