Global mercury hotspots: New evidence reveals mercury contamination regularly exceeds health advisory levels in humans and fish worldwide.

Abstract

Mercury is a well-known neurotoxin that damages the kidneys and many body systems including the nervous, cardiovascular, respiratory, gastrointestinal, hematologic, immune, and reproductive systems (UNEP/WHO 2008).
IPEN and Biodiversity Research Institute (BRI) are collaborating to conduct a global mercury study in response to strong public interest and governmental negotiation of a mercury treaty—the first global treaty on the environment in well over a decade by the United Nations Environment Programme (UNEP). The IPEN-BRI collaboration provides a rare opportunity to compile new and standardized mercury concentrations on a global basis.
The Global Fish and Community Mercury Monitoring Project is the first of its kind to identify, in one collaborative effort, global biological mercury hotspots. These hotspots are of particular concern to human populations and the ecosystems on which they depend.
Based on the U.S. EPA’s reference dose of 0.0001 mg methylmercury per kg of body mass per day, we calculated fish consumption guidelines using an average body mass of 60 kg (132 pounds) and an average fish meal size of 170 grams (6 ounces). Fish containing mercury concentrations of 0.22 parts per million (ppm) should be consumed no more than once per month. Fish with mercury concentrations less than this value (<0.22 ppm) can be consumed more frequently. Fish with mercury concentrations greater than 0.95 should be avoided entirely.

Full text

Global Mercury Hotspots
New Evidence Reveals Mercury Contamination Regularly Exceeds
Health Advisory Levels in Humans and Fish Worldwide
A Publication by the
Biodiversity Research Institute
and IPEN
January 9, 2013

2
e Global Fish and Community Mercury Monitoring Project
Major Findings
Mercury is a well-known neurotoxin that damages
the kidneys and many body systems including the
nervous, cardiovascular, respiratory, gastrointestinal,
hematologic, immune, and reproductive systems
(UNEP/WHO 2008).
IPEN and Biodiversity Research Institute (BRI) are
collaborating to conduct a global mercury study in
response to strong public interest and governmental
negotiation of a mercury treaty—the first global
treaty on the environment in well over a decade
by the United Nations Environment Programme
(UNEP). The IPEN-BRI collaboration provides a
rare opportunity to compile new and standardized
mercury concentrations on a global basis.
The Global Fish and Community Mercury Monitoring
Project is the first of its kind to identify, in one
collaborative eort, global biological mercury
hotspots. These hotspots are of particular concern
to human populations and the ecosystems on which
they depend.
• Theextentofsignicantmercury
contaminationisubiquitousinmarineand
freshwaterecosystemsaroundtheworld.
• Biologicalmercuryhotspotsareglobally
commonandcanberelatedtohuman-generated
mercuryreleasestoair,land,andwaterfrom
multiplepointandnonpointsourcetypes.
• Fishsamplesfromaroundtheworldregularly
demonstratemercuryconcentrationsexceeding
humanhealthadvisoryguidelinesbasedonthe
U.S.EnvironmentalProtectionAgency(EPA)
referencedose.Thistranslatesto84percentof
totalsampleswereabovethelevelatwhichone
mealpermonthisrecommended.
• Hairsamplesfromaroundtheworldregularly
demonstratemercuryconcentrationsexceeding
shconsumptionadvisorylevelsbasedonthe
U.S.EPAreferencedose,whichtranslatesto82
percentabovetheguidelines.
Mercury is present in dierent forms, but the organic
form of mercury, methylmercury, is especially toxic to
humans and wildlife because it is readily absorbed by the
body and can accumulate in places such as the brain.
People become exposed to methylmercury primarily
through the consumption of fish. Many national and
international health organizations recognize mercury
in fish as a threat to human health, livelihoods, and
the environment. However, these same organizations,
particularly in developing and transitioning countries,
have limited or no information about the mercury
levels in fish and other food items of risk. The IPEN-
BRI collaboration begins to bridge these data gaps.
The study generated new data on mercury
concentrations in samples from fish and people to
accomplish the following goals:
1. Raise awareness about global mercury pollution
among the general public, policymakers, and the
human health assessment community
2. Identify and characterize biological mercury
hotspots around the world
3. Explore how the proposed treaty might aect
mercury pollution at these hotspots
For an explanation of the graphs used throughout
this report, turn to the Appendix on page 18.

3
United Nations Environment Programme
(UNEP)
Global Treaty on Mercury
In 2010, an intergovernmental treaty negotiations
process began to develop a global treaty to
control mercury. UNEP is leading this eort with
the aim to adopt a treaty in 2013. IPEN’s global
network of public health and environmental
organizations brings a public interest perspective
to the negotiations. BRI is a member of the
UNEP Mercury Air Transport and Fate Research
Partnership and is contributing with new research
related to global mercury monitoring.
Global Sources and Trends of Mercury
Concentrations of mercury in the global environment
have increased approximately three-fold as a result
of human activities. While industrial emissions have
declined in North America and Europe during the
past two decades, emissions have more than doubled
in East Asia and India over a similar time period
(Figure 1; Pacyna et al. 2010; Wilson et al. 2012).
The United Nations Environment Programme (UNEP)
and the Arctic Monitoring and Assessment Program
(AMAP) estimate global mercury emissions to air from
human-generated sources for 2010 total approximately
2063 metric tons (Figure 2; Wilson et al. 2012).
Fossil fuel combustion and small-scale gold mining
account for more than two-thirds of the 2010 mercury
emissions to air (Figure 2; Wilson et al. 2012). Note
that since there appear to be no available data on
mercury air emissions from vinyl chloride monomer
(VCM) production, emissions from this source are
counted as zero. However, more mercury is used in
VCM production than in most other intentional
sources (UNEP/AMAP 2008).
Finally, some mercury sources release large quantities
of mercury to soils, water, and wastes. Mercury that
is released to media other than air will frequently
contaminate aquatic ecosystems and contribute to
the total global mercury pollution (Figure 3). In
addition, much of this mercury will volatilize and
enter the air at a later time.
Figure 2. Global mercury emissions to air from human-
generated sources for 2010. Value represents an average
emissions estimate from each sector. Data obtained from the
UNEP/AMAP global assessment of mercury emissions into the
atmosphere (Wilson et al. 2012).
Figure 1. Global distribution of human-generated atmospheric emissions of mecury for 2005 (Pacyna et al. 2010).
Waste incine ration
Chlor-alkali plants
Large-scale gold mining
Other (includes cremations
and other waste sources)
Cement manufacturing
Non-ferrous mining/smelting
Fossil fuel combustion
(includes oil refining, coal and
oil combustion for domestic and
industrial uses, and power plants)
Artisanal small-scale gold mining
<1%
2%
5%
5%
11%
14%
31%
32%
Waste incineration
Chlor-alkali plants
Large-scale gold mining
Other (includes cremations
and other waste sources)
Cement manufacturing
Non-ferrous mining/smelting
Fossil fuel combustion
(includes oil refining, coal and
oil combustion for domestic and
industrial uses, and power plants)
Artisanal small-scale gold mining
<1%
2%
5%
5%
11%
14%
31%
32%

4
United States - Alaska
Specific Location Anchorage
Sample Type Fish (43%)*
NGO Participant Alaska Community
Action on Toxics
Potential Hg Source Global Deposition
Associated Pages 14-15
Mexico
Specific Location Coatzacoalcos
Sample Type Hair (73%)*
NGO Participant Centro de Análisis y Acción en
Tóxicos y sus Alternativas
Ecología y Desarrollo
Sostenible en Coatzacoalcos
Potential Hg Source Mixed Use Chemical Industry
Associated Pages 12-13
Cook Islands
Specific Location Muri
Sample Type Hair (89%)*
NGO Participant Island Sustainability
Alliance CIS Inc.
Potential Hg Source Global Deposition
Associated Pages 14-15
Cameroon
Specific Location Douala, Takele Fishing
Settlement
Sample Type Hair (79%)*
NGO Participant Centre de Recherche
et d'Education pour le
Développement
Potential Hg Source Mixed-Use Industry
Associated Pages 12-13
Albania
Specific Location Vlora Bay
Sample Type Fish (50%)*
NGO Participant EDEN Center
Potential Hg Source Contaminated Site
Associated Page 8
Italy
Specific Location Messina
Sample Type Fish (100%)*
NGO Participant Arnika - Toxics and
Waste Programme
Potential Hg Source Global Deposition
Associated Pages 14-15
Portugal - Azores
Specific Location Ponta Delgada, Sao
Miguel
Sample Type Fish (100%)*
NGO Participant Arnika - Toxics and
Waste Programme
Potential Hg Source Global Deposition
Associated Pages 14-15
Uruguay
Specific Location Montevideo
Sample Type Fish (100%)*
NGO Participant Red de Accíón en Plaguicidas y sus
Alternatives para América Latina
Potential Hg Source Global Deposition
Associated Pages 14-15

5
Cameroon
Specific Location Douala, Takele Fishing
Settlement
Sample Type Hair (79%)*
NGO Participant Centre de Recherche
et d'Education pour le
Développement
Potential Hg Source Mixed-Use Industry
Associated Pages 12-13
Tanzania
Specific Location Matundasi and Makongolosi
Sample Type Hair (67%)*
NGO Participant Agenda for Environment and
Resonsible Development
Potential Hg Source Artisanal Small-Scale Gold Mining
Associated Pages 10-11
Indonesia
Specific Location Sekotong, Poboya
Sample Type Hair (95%)*
NGO Participant BALIFOKUS Foundation
Potential Hg Source Artisanal Small-Scale
Gold Mining
Associated Pages 10-11
Japan
Specific Location Tsukiji, Tokyo
Sample Type Fish (100%), Hair (95%)*
NGO Participant Citizens Against Chemicals
Pollution
Potential Hg Source Global Deposition
Associated Pages 14-15
Russia
Specific Location Krasnoarmeyskiy, Volgograd
Sample Type Fish (97%), Hair (68%)*
NGO Participant Information Center “Volgograd Eco-Press”
Eco Accord
Potential Hg Source Chlor-Alkali Facilities
Associated Pages 6-7
Albania
Specific Location Vlora Bay
Sample Type Fish (50%)*
NGO Participant EDEN Center
Potential Hg Source Contaminated Site
Associated Page 8
Figure 3. Geographic Scope of the IPEN-BRI Project
The Global Fish and Community Mercury Monitoring Project engaged IPEN Participating
Organizations to collect samples of fish and human hair among communities of people
living or working in targeted areas with known or suspected mercury contamination.
Samples were sent to BRI’s mercury laboratory for analysis. This report includes results
from 14 countries from all UN regions.
* (% above health advisory)
Czech Republic
Specific Location River Labe - Decin,
Valtirov, Obristvi
Sample Type Fish (88%)*
NGO Participant Arnika - Toxics and Waste
Programme
Potential Hg Source Chlor-alkali Facilities
Associated Pages 6-7
Thailand
Specific Location Tha Tum
Sample Type Fish (85%), Hair (100%)*
NGO Participant Ecological Alert and
Recovery
Potential Hg Source Coal-fired Power Plant
Associated Pages 9

6
Mercury Source: Chlor-Alkali Facilities
Hotspots in Czech Republic and Russia
From the 1890s through the mid-20th century,
mercury-cell technology was the main commercial
process used for the produc tion of chlorine and sodium
hydroxide—two of the most commonly used chemicals
worldwide. The process, still used today, involves large
quantities of mercury and is a major source of mercury
pollution. Each mercury-cell plant facility may contain
hundreds of tons of elemental mercury (see Box 1).
Spolana in Neratovice and Spolchemie in Ústí
nad Labem, Czech Republic
Two plants using mercury-cell processes in the Czech
Republic, Spolana in Neratovice and Spolchemie in Ústí
nad Labem, are located close to the River Labe, which
flows to Germany and into the North Sea. Government
reporting data by the plants in 2011 shows releases of
mercury to air (125 kg) and water (10 kg), and transfers
to wastewater (19 kg) and wastes (>2000 kg).
Volgograd, Russia
The JSC “Kaustik” chlor-alkali plant in Volgograd
is close to the Volga River. The plant uses mercury
cell and diaphragm processes, which release mercury
directly into the air. A waste water disposal system
releases almost 400 kg of mercury per year into local
waterways. Mercury contamination is also found at
waste sites where large drums are stored on the bare
ground without protective covers.
Results of Mercury Exposure—Czech Republic
Eighty-three percent of the freshwater bream and
50 percent of the crucian carp sampled downstream
from the plants in the Czech Republic exceeded the
fish consumption advisory level of 0.22 ppm (Figure
4). Three of the eight freshwater bream from Obristvi
near Neratovice also exceeded the EU limit for mercury
in fish (0.5 ppm). The highest mercury levels in the
Czech Republic samples were more than seven times
greater (1.58 ppm) than the monthly fish consumption
advisory level.
The chlor-alkali plant Spolana in Neratovice lies on the River Labe.
Relevance to the Global Mercury Treaty
Current treaty text proposes elimination of mercury
in chlor-alkali production in either 2020 or 2025.
However, no agreement exists on whether countries
must identify and characterize mercury use at chlor-
alkali facilities or whether to allow new mercury-cell
chlor-alkali facilities under certain circumstances in
the future. Figure 4. Mercury content of fish sampled from the River Labe,
Czech Republic.
Decin and Valtirov,
Freshwater bream (n=6)
Decin, Crucian carp (n=2)
Obristvi, Freshwater bream (n=8)
Fish Mercury (ppm, ww)
0.0
0.2
0.4
0.6
0.8
1.0
Fish consumption
advisory level
(0.22 pppm)
Czech Republic

7
JSC Kaustic Sewage Pond, Carp (n=10)
Sarpa Lake, Perch (n=10)
Volga River, Catfish (n=10)
Volgograd region (n=28)
Fish Mercury (ppm, ww)
0.0
0.2
0.4
0.6
0.8
1.0
Hair Mercury (ppm, fw)
0.0
1.0
2.0
3.0
4.0
Fish Hg
Hair Hg
Fish consumption
advisory level
(0.22 pppm)
Hair reference
dose level
(1.0 ppm)
Box 1
Mercury in the Chlor-Alkali
Manufacturing Process
A – Electrodes are in contact with a saltwater (brine) solution. The
anode (positively charged electrode) is graphite or titanium; the
cathode (negatively charged electrode) is a large pool of mercury (Hg)
that may weigh several hundred tons. An electri cal current passed
across the electrodes creates chlorine gas (Cl2), which
is vented and collected, and a sodium-mercury amalgam (Na-Hg),
which is further processed.
B – Subsequently, a reaction between the metallic sodium in this
amalgam and water is induced to produce sodium hydroxide (NaOH)
and hydrogen gas (H2), which are collected for industrial use. The
mercury from the amalgam is captured and recycled back to the
cathode of the mercury cell. During this process, mercury is released
both into the atmosphere and into wastewater.
Saturated
Brine
Depleted
Brine Cathode (-)
Anode (+)
Sodium
Ions
(Na +)
Chlorine gas (Cl2)
(Cl -)
Chloride
Ions
Na - Hg amalgam
Hg
Graphite
catalyst
Hydrogen gas
(H2)
H2
Na+
OH-
H2O
caustic soda (NaOH)
+ H2O
Recycled Hg
(return to
cathode cell)
Hg
Hg loss to air
Hg loss to water
Na-Hg amalgam
to decomposer
A
Figure 5. Fish samples were collected from three dierent locations in Russia
including a sewage pond adjacent to the plant along the Volga River and Sarpa Lake,
further downstream from where the Volga River drains.
B
Results of Mercury Exposure—
Russia
Mercury levels in fish from the surface
waters in Volgograd, Russia exceeded
the fish consumption advisory level of
0.22 ppm, the U.S. EPA reference dose
limit for all three species (Figure 5).
The highest mercury levels in these
samples were nearly four times greater
than the fish consumption advisory
level. Nine of 10 carp samples (90
percent) from the sewage pond and all
of the fish sampled in the Volga River
and Sarpa Lake were above the fish
consumption advisory level.
Hair samples collected from two
communities near the facility had a
mean mercury concentration of
1.93 ± 1.50 ppm, with 67 percent
of the samples being above the U.S.
EPA reference dose level of 1.0 ppm
(Figure 5).
Russia
Fish Hg
Hair Hg

8
Mercury Source: Contaminated Sites
Representatives of a local public interest organization visit an
abandoned PVC plant in Albania, the site where waste products
from the working plant (including mercury chloride) were
dumped. There are no restrictions for public exposure to this site.
Figure 6. Mercury content of fish sampled in Vlora Bay, Albania.
Relevance to the Global Mercury Treaty
The current treaty text does not require the
identification and cleanup of contaminated
sites. In addition, the current treaty text provides
no guidance on a health-protective value that
defines waste as hazardous nor does it require
the minimization and prevention of generating
mercury-containing waste.
Finally, since the treaty links compliance with
funding and since action on contaminated sites is
not obligatory, it is likely that no funding will be
available through the treaty’s financial mechanism
to identify or clean up contaminated sites.
Hotspot in Albania
Contaminated sites contribute to remobilization
and re-emissions of mercury, a significant source and
pathway of mercury air emissions.
Vlora Bay, Albania
The former chlor-alkali and PVC plant in Vlora used
a mercury-cell process, discharged its waste directly
into Vlora Bay, and dumped polluted sludge near the
seashore where it remains today. The plant operated
from 1967–1992; its buildings have been completely
destroyed since then. No precautions have been taken
to prevent further contamination of the bay or nearby
residents. In 2002, an identification mission of UNEP/
MAP (GEF Project GF/ME6030-00-08) identified this
area as a hotspot after a soil sample showed mercury
levels greater than 10,000 ppm in the area of the
former plant—1000 times greater than typical EU
thresholds. Vlora Bay is an important fishing area; fish
from the area are distributed to all cities in Albania.
Results of Mercury Exposure
European hake and surmullet (or red mullet) were
collected from Vlora Bay. Four of the eleven hake (36
percent) contained mercury concentrations above the
fish consumption advisory level of 0.22 ppm (Figure 6).
All surmullet (100 percent) were above the fish
consumption guideline with a mean concentration of
0.62 ± 0.31 ppm (ww). Other studies in Vlora Bay have
also documented high mercury levels in fish and plants
in this area (Storelli et al. 1998; Mankolli et al. 2008 ).
European hake (n=11)
Surmullet (n=3)
Fish Mercury (ppm, ww)
0.0
0.2
0.4
0.6
0.8
1.0
Fish consumption
advisory level
(0.22 pppm)
Albania

9
Mercury Source: Coal-Fired Power Plants
Hotspot in Thailand
Coal is the most abundant fossil fuel on Earth and
the combustion of coal releases mercury into the
environment. Air emissions from poorly controlled
plants can emit large quantities of particle-bound
mercury, which tend to fall to Earth downwind of
these power plants. Mercury in fly ash, which is
captured by air pollution control devices, can also be
subsequently released to the environment. Pulp and
paper plants can be another mercury source when
phenyl mercury acetate is added to inhibit the growth
of fungi and contaminates the discharge water.
Tha Tum, Thailand
The Tha Tum site contains 75 factories including a
coal-fired power plant consuming 900,000 tons/year
of coal (adjacent to a pulp and paper mill producing
500,000 tons/year of paper that can also release
significant amounts of mercury [Kim et al. 2010]).
Fish are commonly eaten from the Shalongwaeng
Canal, which runs nearby the pulp and paper plant,
and the open-air storage of coal and fly ash from the
power plant.
Figure 7. Mercury content in fish and hair sampled from a site
near a coal-fired power plant in Tha Tum, Thailand.
Relevance to the Global Mercury Treaty
The current treaty text on air emissions oers vague
options for controlling existing coal-fired power
plants if they are above a certain thermal input (not
yet determined). However, these provisions are not
likely to reduce mercury emissions from individual
plants on a scale sucient to oset the new mercury
emissions that are likely to result from the rapid
growth of this sector. Pulp and paper mills are not
listed as a mercury source in the current treaty text,
although the UNEP Mercury Toolkit and U.S. Toxics
Release Inventory data suggest it is a significant
source of emissions.
Top: Hair samples
were taken from
people who lived
near mercury
sources.
Left: Fish most
often consumed
by the local
population, like
this common
snakehead, were
sampled for
mercury content.
Results of Mercury Exposure
Snakehead fish regularly exceeded the fish consumption
advisory level (over 85 percent of the samples; Figure 7). In
addition, all 20 hair samples from residents living 0.5–
2.0 km from the power plant and pulp mill exceeded
the U.S. EPA reference dose, and average levels were
more than 4.5 times higher than 1.0 ppm (Figure 7).
Tha Tum, Common snakehead (n=20)
Tha Tum (n=20)
Fish Mercury (ppm, ww)
0.0
0.2
0.4
0.6
0.8
1.0
Hair Mercury (ppm, fw)
0.0
2.0
4.0
6.0
8.0
Fish Hg
Hair Hg
Fish consumption
advisory level
(0.22 pppm) Hair reference
dose level
(1.0 ppm)
Thailand
Fish Hg
Hair Hg

10
Mercury Source: Artisanal Small-Scale Gold Mining
Hotspots in Tanzania and Indonesia
Artisanal small-scale gold mining (ASGM) is the
largest intentional use of mercury (30 million people
are engaged in artisanal gold mining around the
world), causing extreme pollution and contributing
directly to human body burdens through mercury
vapors and high levels of methylmercury in food items
such as fish from local waterways near ASGM sites.
Matundasi and Makongolosi, Tanzania
The Tanzanian ASGM sites in the Matundasi and
Makongolosi areas burn mercury-gold amalgam in the
open air without recovery systems (see Box 2). Most of
the water that is used for sluicing and amalgamation
drains into the Lupa River which flows into Lake
Rukwa, an important waterway which supports
livelihoods in the southern highland part of Tanzania
and borders a large Ugandan game reserve.
Sekotong and Poboya, Indonesia
In 2010, about 280 tons of illegal mercury was imported
to Indonesia for ASGM. This figurehas doubled in
2011 (2012 Ismawati personal communication). In
Sekotong Village, almost every household operates a
ball-mill unit, located in the backyard or near the rice
field. Miners process ore all day long without personal
protection equipment.
In Poboya, the ball-mills are concentrated in clusters
and release very high levels of mercury vapor to the air
and the environment (Serikawa et al. 2011; Ismawati
and Gita 2011). In both hotspots, the mercury-
contaminated tailings are either processed further in a
cyanide leaching plant or disposed directly into rivers.
Results of Mercury Exposure
In Tanzania, two-thirds of the samples exceeded the U.S.
EPA reference dose. The average mercury concentration
was 2.74 ± 3.4 ppm (fw), excluding a significant outlier
of 236 ppm (fw). The average mercury level in human
hair at both sites in Indonesia (Sekotong Village and the
Poboya area in Palu) was more than three times greater
than the U.S. EPA reference dose. The mean mercury
level in hair from Sekotong Village was 3.6 ± 1.3 ppm
(fw). The mean mercury level in hair from Poboya was
5.0 ± 4.7 ppm (fw) with a maximum concentration
of 13.3 ppm. Overall, 19 of the 20 samples collected
from these Indonesian villages exceeded the U.S. EPA
reference dose (see Figure 8).
Figure 8: Mercury content in human hair from ASGM sites in
Tanzania and Indonesia.
Although mercury use for ASGM is illegal in Tanzania, there are
approximately 150–200 miners working at the two sites noted
in this report. The Indonesian sites in Poboya and Sekotong
encompass 40,000 miners and 300 active milling operations.
Tanzania - Matundasi and
Makongolosi (n=14)
Indonesia - Sekotong (n=10)
Indonesia - Poboya (n=10)
Hair Mercury (ppm, fw)
0.0
2.0
4.0
6.0
8.0
10.0
Hair reference
dose level
(1.0 ppm)
Tanzania and Indonesia

11
Mercury Source: Artisanal Small-Scale Gold Mining Mercury in the
Artisanal Small-Scale
Gold Mining Process
To extract gold dust from the
earth, artisanal miners add
mercury to the silt. This can be
done in an apparatus known as
a ball-mill (mercury is poured
into large drums that contain
silt, as shown at left). The gold
particles attach to themercur y,
which acts like a magnet to the
precious metal. The result is a
solid mercury-gold amalgam
that can be separated out by
screening the silt.
The mercury-gold amalgam
is then heated to vaporize
the mercury, leaving the gold
nuggets behind. Because this
process is often conducted in
the open air, usually close to
family dwellings, anyone in the
near vicinity is at risk of inhaling
the airborne mercury.
Excess mercury that is left in
the silt (known as mine tailings)
finds its way into local waterways
during disposal.
Photos from top: In the Indonesian village of Sekotong,
workers add liquid mercury to the ball-mill; the mercury-
gold amalgam is heated, releasing mercury into the air.
Right: In Poboya, a local miner operates a gold shop—the
fumes from his makeshift torching apparatus (stacked
barrels) stands in close proximity to the family dwelling.
Relevance to the Global Mercury Treaty
The current treaty text requires actionsifParties
determine that ASGM is “more than insignificant,”
however there are no guidelines to determine
“significance.” In addition,the current text allows
countries to importunlimited quantities of
mercury for use in ASGM with no phase-out date.
Finally, no obligations exist to identify or clean up
contaminated ASGM sites.
Box 2

12
Mercury Source: Mixed-Use Chemical Industrial Sites
Hotspots in Mexico and Cameroon
Mixed-use industrial sites can include chlor-alkali
production, oil refining, waste incineration, cement
manufacturing, and other potential mercury sources
that contribute varying amounts of mercury to
total releases. This type of hotspot represents a real-
world situation that most cities and countries will
face—identifying and dealing with mercury pollution
released by a complex mixture of mercury sources.
The industrial sites examined in this study are adjacent
to rivers that flow into the ocean. These sites were
analyzed to determine whether a mixture of mercury
sources can result in human body burdens of mercury.
Coatzacoalcos and Minatitlán, Mexico
In Mexico, the city of Coatzacoalcos, Veracruz
contains a mercury-cell chlor-alkali plant inside
of a petrochemical complex that includes a waste
incinerator. Another site in Mexico, located in
Minatitlán, Veracruz, contains an oil and gas refinery
which was recently configured to increase processing
capacity to 350,000 barrels per day. Both sites are
located on the Coatzacoalcos River, which flows into
the Gulf of Mexico.
Douala, Cameroon
Douala, the largest and most industrial city in
Cameroon is located at the mouth of the Wouri
River which empties into the Gulf of Guinea. Douala
contains a cement plant (more than 1.2 million tons
produced in 2009), waste incinerator, e-waste dumping
and open burning, and a variety of other potential
mercury sources including skin-whitening products.
The study focused on the fishing community of
Youpwe-Takele.

A woman on the way back from fishing in Douala, Cameroon.
Wetland areas are especially prone to creating high
concentrations of mercury in fish.
Relevance to the Global Mercury Treaty
The current treaty text oers some vague options
for controlling air emissions from existing cement
kilns and waste incinerators if they are above a
certain output threshold (not yet determined).
However, these provisions may not reduce mercury
emissions from individual plants on a scale
sucient to oset the new mercury emissions that
come from increased numbers of cement kilns or
incinerators.
Neither cement kilns nor waste incinerators are
included as a possible source of mercury releases
to land or water.
There is also no agreement about whether to
include oil and gas production and processing
facilities in the treaty, so this possible source of
mercury may not be addressed. The current treaty
text prohibits soaps and cosmetics containing
mercury but there is no agreement on the phase-
out date.
The current treaty text also permits new mercury-
added products to be introduced into the market
if it can be justified based on “compensating
environmental or human health benefits.”
Used electronic devices such as computers and/or
e-waste could also be one of potential sources of
mercury releases in Douala, as it is in other African
countries. The current treaty text does not include
open burning of these types of wastes as an air
emission source.

In Douala, Cameroon, local fishermen clean their catch from
the Wouri River.

13
Mercury Source: Mixed-Use Chemical Industrial Sites
Results of Mercury Exposure
The average mercury level in human hair from Mexico
was 1.75 ± 1.1 ppm (fw) with 73 percent of samples
exceeding the U.S. EPA reference dose of 1.0 ppm (fw)
(Figure 9). The maximum concentration of 4.32 ppm
was more than four times higher than the reference
dose.
In Cameroon, the average mercruy level in human hair
was 1.93 ± 1.1 ppm (fw) with 76 percent of the samples
exceeding the U.S. EPA reference dose of 1.0 ppm (fw)
(Figure 9). The maximum concentration of 3.77 ppm
was nearly four times higher than the reference dose.
This excludes two samples with extremely high
mercury levels of 541 and 546 ppm (fw). Pathways for
such high mercury exposure in humans could include
cosmetics such as skin-lightening products. These
individual hair samples were re-analyzed to confirm
the accuracy of the initial analysis, and the second
round of analysis confirmed highly elevated mercury
levels in the hair.
The sprawling
Pajaritos
petrochemical
complex in
Coatzacoalcos, a
major port city in
Veracruz, Mexico
that lies on the
Coatzacoalcos
River.
Figure 9. Mercury content in human hair near mixed-use
industrial sites in Mexico and Cameroon.
Mexico (n=22)
Cameroon (n=17)
Hair Mercury (ppm, fw)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
Hair reference
dose level
(1.0 ppm)
Mexico and Cameroon

14
Mercury Sources: Global Atmospheric Deposition
The release of mercury is of global importance
because of its ability to move across large spaces via
air and water currents (Figure 10). It is released into
the environment predominantly through human
activities and such inputs over time have increased
the biosphere levels of mercury by at least three-fold
(Mason et al. 2012).
Atmospheric processes can carry emitted mercury
around the world for approximately one year until
being deposited on the Earth’s surface. The world’s
oceans are one of the primary environmental reservoirs
where mercury is deposited from the air or from inputs
from river watersheds. While atmospheric deposition
is the greatest source of mercury to oceans, internal
production from the upper 3,300 feet (1,000 meters) of
water in the open ocean provides the greatest input of
methylmercury in marine fish (Mason et al. 2012).
Based on models by Sunderland et al. (2009), present
atmospheric mercury deposition rates will result
in mercury concentrations doubling in the North
Pacific Ocean by 2050; such deposition rates are
likely to result in significant mercury increases in
pelagic marine fish, such as the Pacific bluefin tuna,
if methylmercury production and accumulation
mimics projected mercury additions. Fish mercury
concentrations vary by ocean basin because of
mercury inputs, large-scale ocean circulation, vertical
transport processes (Mason et al. 2012), and species
composition and harvest pressure (Evers et al. 2012).
Relevance to the Global Mercury Treaty
The current treaty text oers few true mechanisms
for controlling exisiting emissions sources and
there are significant gaps including:
• Only vague options for controlling emissions
from exisiting coal-fired power plants
• Unlimited importation of mercury for ASGM
purposes with no phase-out date
• No language identifying VCM production
as a mercury source and no text prohibiting
mercury during VCM production
Without a more deliberate eort to address these
issues, global mercury emission and deposition
will likely continue to increase.
Indicators of Ocean Basins
Apex marine predators such as tuna, swordfish, and
other large pelagic fishes are important species for the
global marine fisheries (Evers et al. 2012, FAO 2012,
Karimi et al. 2012). However, these same species are
also most susceptible to mercury exposure because of
their position at the top of the marine food web.
We selected six sites from across the Earth’s oceans
(Table 1) to examine mercury concentrations in top
marine predatory fishes and also the potential risks of
exposure in human populations that rely on marine
fisheries for their diet.
Figure 10. Map shows global mercury (Hg) deposition and total Hg entrainment across the Earth’s oceans. Global deposition
including wet, dry, and particulate Hg, shows peaks in the North Atlantic, adjacent to the northeastern U.S. as well as in the North
Pacific, adjacent to Asia. Additional peaks in deposition at higher latitudes are associated with long-term transpor t of Hg in the
upper atmosphere and subsequent deposition. High concentrations of inorganic Hg in the North Atlantic and the tropical regions
are largely controlled by surface ocean circulation patterns. (Image derived from Soerensen et al. 2010.)
Atmospheric Deposition Net Inorganic Mercury Circulation Patterns
Hotspots—The World’s Oceans as Reservoirs for Mercury

15
Mercury Sources: Global Atmospheric Deposition
Ocean Basin Country Tissue Type Sampled
Northern Pacific Japan fish / hair
Northern Pacific United States (Alaska) fish
Southern Pacific Cook Islands hair
Eastern Atlantic Portugal - Azores fish
Southern Atlantic Uruguay fish
Mediterranean Sea Italy fish
Table 1. Ocean basins and countries where samples were collected.
Figure 12. Mercury content in human hair from
local populations in Japan and the Cook Islands.
Bluefin tuna sold at the Tsukiji market in Tokyo, Japan. The
bluefin tuna sampled in this project, purchased from this
market, contained among the highest mercury levels detected.
Results of Mercury Exposure
Of the 28 fish samples collected from the global
atmospheric deposition sites, 86 percent were above the
fish consumption guideline of 0.22 ppm (Figure 11).
Forty-three percent were above the EU and WHO limit
of 1.0 ppm.
Swordfish from the Southern Atlantic Ocean
(Uruguay) had the highest average mercury level of
1.31 ± 0.16 ppm (ww), followed by Pacific bluefin
tuna (1.12 ± 0.24 ppm, ww) from the Northern Pacific
Ocean (Japan). Albacore tuna from the Mediterranean
Sea (Italy) had an average mercury level of 0.91 ± 0.35
ppm (ww).
Average mercury levels in hair from Tokyo were 2.7
times higher than the U.S. EPA reference dose, and the
Cook Islands hair samples contained average mercury
levels that were 3.3 times higher than the reference
dose (Figure 12).
Overall, 95 percent of the hair samples from Japan
and 89 percent of the samples from the Cook Islands
exceeded the U.S. EPA reference dose for mercury.
Figure 11. Mercury content in large pelagic fish.
U.S-Alaska - Halibut (n=7)
Portugal-Azores - Black scabbardfish (n=2)
Italy - Albacore (n=6)
Japan - Pacific bluefin tuna (n=9)
Uruguay - Swordfish (n=4)
Fish Mercury (ppm, ww)
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
Fish consumption
advisory level
(0.22 pppm)
Global Ocean Basins
Japan - Tokyo (n=19)
Cook Islands - Muri (n=9)
Hair Mercury (ppm, fw)
0.0
1.0
2.0
3.0
4.0
5.0
Hair reference
dose level
(1.0 ppm)
Pacific Oceans

16
Summary
Mercury in Fish
The IPEN-BRI collaboration generated fish mercury
concentrations from three types of common mercury
point sources: contaminated sites, chlor-alkali
facilities, and coal-fired power plants. Sites likely
related primarily to nonpoint sources, or global
deposition, are also identified. Each of the nine
countries contained high proportions of fish over the
USEPA reference dose-based consumption guideline
of 0.22 ppm (where only one fish meal of 170 grams
[or 6 ounces] per month should be consumed). Our
findings demonstrate that 84 percent of the fish
sampled were not safe for consumption for more than
one meal per month (Figure 13). Over 13% of the fish
sampled would not be recommended by The World
Health Organization and the European Commission
for commercial sale.
Mercury in Human Hair
Mercury in human hair was collected from two
countries with global deposition as a source, while
other countries are directly related to three types of
point source releases; artisanal small-scale gold mining
(ASGM), coal-fired power plants, and mixed industrial
sites that contain mixtures of chlor-alkali production,
oil refining, waste incineration, and cement
manufacturing. More than 82 percent of the 152
individuals contained mercury concentrations greater
than the USEPA reference dose level of 1.0 ppm.
This study identified global biological mercury hotspots that are of particular concern to human populations
and the ecosystems on which they depend. Five types of major mercury point sources were chosen to examine
mercury pathways from their origin to methylmercury exposure in fish and people.
Sites represent releases of mercury to air, land and water. The major source type of global deposition originates
from nonpoint sources. The data in this report represents 108 fish samples from nine countries and 152 human
hair samples from eight countries. The countries represent all regions in the United Nations regions and include
a mix of developed countries, developing countries, and countries with economies in transition along with one
Small Island Developing State.
Relevance to the Global Mercury Treaty
The United Nations Environment Programme
(UNEP) is supporting intergovernmental
negotiations to develop a global, legally binding
treaty on mercury to reduce risks to human
health and the environment. This IPEN-BRI study
highlights the global scale and ubiquitous nature
of mercury contamination and reinforces eorts
to develop a comprehensive and eective global
mercury treaty.
Figure 13. The percentage of fish samples from nine countries
above the fish consumption advisory guideline of 0.22 ppm.
U.S.-Alaska (n=7)
Albania (n=14)
Thailand (n=20)
Czech Republic (n=16)
Russia (n=30)
Italy (n=6)
Japan (n=9)
Uruguay (n=4)
Portugal-Azores (n=2)
Percentage of samples above mercury
consumption advisory level for fish
0
20
40
60
80
100
Percentage of Fish Over Advisory Limits
Figure 14. The percentage of human hair samples from eight
countries above the U.S. EPA reference dose of 1.0 ppm.
Tanzania (n=15)
Russia (n=28)
Mexico (n=22)
Cameroon (n=19)
Cook Islands (n=9)
Japan (n=19)
Indonesia (n=20)
Thailand (n=20)
Percentage of samples above mercury
reference does level for hair
0
20
40
60
80
100
Percentage of Hair Over Advisory Limits

17
Literature Cited
Chen, C.Y., Driscoll, C.T., Lambert, K.F., Mason, R.P., Rardin, L.R.,
Schmitt, C.V., Serrel, N.S. and Sunderland, E.M. 2012. Sources to
Seafood: Mercury pollution in the marine environment. Hanover,
NH: Toxic Metals Superfund Research Program, Dartmouth College.
Evers, D.C., Mason, R.P., Kamman, N.C., Chen, C.Y., Bogomolni,
A.L., Taylor, D.H., Hammerschmidt, C.R., Jones, S.H., Burgess,
N.M., Munney, K. and Parsons, K.C. 2008. An integrated mercury
monitoring program for temperate estuarine and marine ecosystems
on the North American Atlantic Coast. EcoHealth 5:426-441.
Evers, D.C., Turnquist, M.A. and Buck, D.G. 2012. Patterns of global
seafood mercury concentrations and their relationship with human
health. Biodiversity Research Institute. Gorham, Maine. BRI Science
Communications Series 2012-48. 16 pages.
FAO 2012. FAO yearbook. Fishery and Aquaculture Statistics, 2010.
Rome, FAO. 78pp.
Ismawati, Y. and Gita, A. 2011. Tracing the invisible hazards. Melacak
bahaya tersembunyi. Lumex sampling result conducted by BaliFokus.
Denpasar, BaliFokus.
Karimi, R., Fitzgerald, T.P. and Fisher, N.S. 2012. A quantitative
synthesis of mercury in commercial seafood and implications for
exposure in the U.S. Environ. Health Perspectives. http://dx.doi.org
doi.org/10.1289/ehp.1205122.
Kim, J.H., Park, J.M., Lee, S.B., Pudasainee, D. and Seo, Y.C. 2010.
Anthropogenic mercury emission inventory with emission factors
and total emission in Korea. Atmospheric Environment 44:2714-
2721.
Lambert, K.F., Evers, D.C., Warner, K.A., King, S.L. and Selin, S.E.
2012. Integrating mercury science and policy in the marine context:
Challenges and opportunities. Environmental Research, http://
dx.doi.org/10.1016/j.envres.2012.06.002.
Mankolli, H., Proko, V. and Lika, M. 2008. Evaluation of mercury
in the Vlora Gulf Albania and impacts on the environment. J. Int.
Environmental Application Science 3:258-264.
Mason, R.P., Choi, A.L., Fitzgerald, W.F., Hammerschmidt, C.R.,
Lamborg, H., Soerensen, A.L. and Sunderland, E.M. 2012. Mercury
biogeochemical cycling in the ocean and policy implications.
Environmental Research 119:101-117.
Pacyna, E.G., Pacyna, J.M., Sundseth, K., Munthe, J., Kindblom, K.,
Wilson, S., Steenhuisen, F. and Maxon, P. 2010. Global emissions of
mercury to the atmosphere from anthropogenic sources in 2005 and
projections to 2020. Atmospheric Environment 44:2487-2499.
Serikawa Y., Inoue T., Kawakami T., Cyio B., Nur I. and Elvince R.
2011. Emission and dispersion of gaseous mercury from artisanal
and small-scale gold mining plants in the Poboya Area of Palu
City, Central Sulawesi, Indonesia. Toyama Prefectural University,
Toyohashi University of Technology; Tadulako University. RS17-P8
Presented at the 10th International Conference on Mercury as
Global Pollutant. Hallifax, Canada, July 2011.
Soerensen, A.L., Sunderland, E.M., Holmes, C.D., Jacob, D.J., Yantosca,
R.M., Skov, H., Christensen, J.H., Strode, S.A. and Mason, R.P. 2010.
An improved global model for air-sea exchange of mercury: High
concentrations over the North Atlantic. Environmental Science &
Technology 44:8574-8580.
Storelli, M.M., Ceci, E., and Marcotrigiano, G.O. 1998. Comparative
study of heavy metal residues in some tissues of the fish Galeus
melastomus caught along the Italian and Albanian coasts. Rapp.
Comm. int. Mer Médit 35: 288-289
Sunderland, E.M., Krabbenhoft, D.P., Moreau, J.W., Strode, S.A.
and Landing, W.M. 2009. Mercury sources, distribution, and
bioavailability in the North Pacific Ocean: Insights from data and
models. Global Biogeochemical Cycles 23: GB2010. 14 pp.
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Organization [WHO]. 2008. Guidance for identifying populations
at risk from mercury exposure. UNEP Chemicals Branch and WHO
Department of Food Safety, Zoonoses and Foodbourne Diseases.
Geneva, Switzerland 176 pp.
United States Environmental Protection Agency [USEPA]. 2000.
Guidance for Assessing Chemical Contaminant Data for Use in Fish
Advisories. Volume 1: Fish Sampling and Analysis (3rd edition). US
EPA, Oce of Water. EPA 823-B-00-007. Washington, DC. 485 pp.
Wilson, S., Kindbom, K., Yaramenka, K., Steenhuisen, F. and Telmer,
K. 2012. UNEP/AMAP 2012 Technical Report, Part A: Global
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Environment Programme and the Arctic Monitoring and Assessment
Program. 58p.

18
APPENDIX: Methods Behind the Data
Identifying Potential Hotspots and Sample Collection
Work on the Global Fish and
Community Mercury Monitoring
Project was conducted in three
phases. In Phase 1 and 2, IPEN
and its network of more than 700
public interest NGOs from across
the globe collected hair and fish
samples and identified potential
mercury contamination hotspots.
During Phase 3, BRI utilized its
Global Biotic Mercury Synthesis
(GMBS) database to further
identify potential hotspots.
Fish and hair sampling protocols
were adapted from approved
sampling methods for mercury
risk assessment in fish (U.S. EPA
2000) and human hair (UNEP/
WHO 2008). For fish sampling, we
targeted high trophic level fish and
fish commonly consumed by the
local population.
Hair samples were collected from
individual volunteers (of legal age)
who live adjacent to the hotspot.
The majority of samples (fish and
hair) were shipped by expedited
international shipping to BRI’s
Wildlife Mercury Research Lab for
analysis. Results are shown in this
report using bar graphs that depict
the average mercury measured in
parts per million (Box 3).
Evaluating the Results
Based on the U.S. EPA’s reference dose of 0.0001 mg methylmercury per
kg of body mass per day, we calculated fish consumption guidelines using
an average body mass of 60 kg (132 pounds) and an average fish meal
size of 170 grams (6 ounces). Fish containing mercury concentrations of
0.22 parts per million (ppm) should be consumed no more than once per
month. Fish with mercury concentrations less than this value (<0.22 ppm)
can be consumed more frequently. Fish with mercury concentrations
greater than 0.95 should be avoided entirely. (Table 2.)
Samples were analyzed on BRI’s Milestone
DMA 890, using a U.S. EPA-approved
method (SW-846 Method 7473).
Fish Methylmercury
Concentrations (ppm/ww)
Recommended
Consumption
<0.05 unrestricted
>0.05-0.11 2 meals/week
>0.11-0.22 1 meal/week
>0.22-0.95 1 meal/month
>0.95 no consumption
Table 2. Fish
consumption
guidelines for
methylmercury
based on the
U.S. EPA
reference dose.
The black T line represents
the standard deviation—an
estimate of the variation in
the sample data set.
Fish mercury
concentrations are
shown in blue.
A mercury concentration
of 0.22 ppm corresponds
to a fish consumption
guideline of no more than
one meal per month.
Hair mercury
concentrations are
shown in green.
Box 3. Interpreting the Bar Graphs
Country and/or location
(n = samples size)
Hair Mercury (ppm, fw)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Hair reference
dose level
(1.0 ppm)
Location, Fish species
(n = smaple size)
Fish Mercury (ppm, ww)
0.0
0.2
0.4
0.6
0.8
1.0
Fish consumption
advisory level
(0.22 pppm)
Measurements:
p p m = parts per
million
w w = wet weight
f w = fresh weight
U.S. EPA’s reference dose
for mercury in human hair.
Mercury concentrations
above 1.0 ppm in hair
have been related to
neurological impairments
and other adverse eects.
The top of the
graph represents the
arithmetic mean.

19
Acknowledgments
IPEN and BRI would like to acknowledge contributions from the following IPEN Participating Organizations that collected samples for
mercury analysis and submitted reports characterizing the collection sites. Specifically, we would like to recognize the following organizations:
EDEN Center, Albania; Centre de Recherche et d’Education pour le Développement (CREPD), Cameroon; Island Sustainability Alliance CIS
Inc. (ISACI), Cook Islands; Arnika Association, Czech Republic; BALIFOKUS Foundation, Indonesia; Citizens Against Chemicals Pollution
(CACP), Japan; Centro de Análisis y Acción en Tóxicos y sus Alternativas (CAATA), Mexico; Ecología y Desarrollo Sostenible en Coatzacoalcos,
A.C., Mexico; Information Center “Volgograd Eco-Press”, Russia; Eco Accord, Russia; Agenda for Environment and Resonsible Development
(AGENDA), Tanzania; Ecological Alert and Recovery (EARTH), Thailand; Red de Accíón en Plaguicidas y sus Alternatives para América Latina
(RAP-AL), Uruguay; Alaska Community Action on Toxics (ACAT), United States. In addition, IPEN and BRI would like to acknowledge Shay
Hatch for organizing the international shipments of materials and samples, and Kevin Regan for sample analysis.
IPEN and BRI gratefully acknowledge the financial support from the governments of Sweden and Switzerland, and others. The content and
views expressed in this report, however, are those of the authors and not necessarily the views of the institutions providing financial support.
Suggested Citation for this Report:
Evers, D.C., DiGangi, J., Petrlík, J., Buck, D.G., Šamánek, J., Beeler, B., Turnquist, M.A., Hatch, S.K., Regan, K. 2013. Global mercury hotspots:
New evidence reveals mercury contamination regularly exceeds health advisory levels in humans and fish worldwide. Biodiversity Research
Institute. Gorham, Maine. IPEN. Göteborg, Sweden. BRI-IPEN Report 2013-01. 20 pages.
The Global Biotic Mercury Synthesis Database
A Platform for Evaluating the Eectiveness of the UNEP Mercury Treaty
There is a gap in our understanding about the
relationship between human-generated releases
of mercury into the environment (through air,
water, and land), subsequent biomagnification and
bioaccumulation of methylmercury (how the toxicity
of mercury intensifies as it moves up the food web
over time), and how this translates to exposure and
risks at local, regional, and global scales.
BRI has compiled a Global Biotic Mercury Synthesis
(GBMS) database in association with the Global
Mercury Partnership’s Mercury Air Transport and
Fate Research Group (Evers et al. 2012).
The GBMS database contains a large number of
data sets on mercury concentrations in shellfish,
sharks and rays, fin fish, birds, and marine mammals
from various regions of the world over the past
several decades. It provides an important tool to:
1. Understand the spatial patterns and temporal
trends of mercury concentrations in the
ecosystem;
2. Identify species or groups of organisms that are of
greatest concern for ecological and human health;
3. Locate global biological mercury hotspots, link
with major mercury source types and determine
if concern is related to contaminated sites or
ecosystems sensitive to even small amounts of
mercury input;
4. Distribute information in easy-to-access and
understandable approaches for interested
parties at local, regional, and global levels; and
5. Evaluate the eectiveness of the future global
legally binding treaty on mercury.
GBMS represents a comprehensive, standardized,
and cost eective approach for documenting and
tracking changes in environmental loads of mercury
as reflected in fish and wildlife. The use of key
indicator organisms, such as apex marine predators,
that are sensitive to environmental change is an
integral part of a long-term monitoring program
(Evers et al. 2008; Chen et al. 2012).
The data included in GBMS represents an important
opportunity to better integrate mercury science into
important policy decisions related to the long-term
management of natural resources (Lambert et al. 2012).
Credits:
Editing and Production: Deborah McKew
Photos: Cover: Smoke stack © Alexander Gatsenko; Bluefin tuna © holbox; Fish market in Tanjii © Hans Martens; p. 2 Fishwoman © istock Lugaaa; p. 6 Spolana
© Hana Kuncova (Arnika); Illustration David Buck; p. 8 Abandoned plant courtesy of Eden Center, Albania; p. 9 fish and hair samples courtesy EARTH, Thailand;
p. 10 panning for gold by Haji Rehani (AGENDA, Tanzania); p. 11 Ball-mills © Kemal Jufri (BaliFokus, Indonesia); Gold shop courtesy BaliFokus; p. 12 Fishing in
Cameroon photos courtesy of Centre de Recherche et d’Education pour le Développement (CREPD, Cameroon); p. 13 Chemical plant © Alvaro Balderas; p. 14 Tuna
market in Japan © iStock aluxum; p. 16 Boats in harbor © iStock Manuel Ribeiro fotografo; p. 18 BRI Mercury lab © BRI-Rick Gray; Fish fillet © pitrs/123RF; Back
cover: Ian Johnson, Map Source/citation: ESRI, i-cubed, USDA, USGS, AEX, GeoEye, Getmapping, Aerogrid, IGN , IGP and the GIS User Community.

BRI’s mission is to assess emerging threats to wildlife
and ecosystems through collaborative research, and
to use scientific findings to advance environmental
awareness and inform decision makers.
www.briloon.org
IPEN is a leading global organization working to
establish and implement safe chemicals policies
and practices that protect human health and the
environment around the world.
www.ipen.org
This BRI-IPEN Report is available online at:
www.ipen.org/hgmonitoring
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