Heavy metals in plastic, recycling and environmental aspects

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Parallel Session 10: Environmental and Geochemical Analysis OP33
78
Heavy metals in plastic, recycling and environmental
aspects
A. van Oyen1, J. A. van Franeker2 , U. Oppermann3, M. Egelkraut-Holtus3
1 Research, Harderhook 20, D-1432 Bocholt, CARAT GmbH, Germany
2 Research, PO Box 167, 1790 AD Den Burg Texel, IMARES, Netherlands
3Spectroscopy, Albert- Hahn- Str. 6-10, D-47269 Duisburg, Shimadzu Europa GmbH, Germany
E-mail: Albert.van.Oyen@Carat-lab.vom
Plastic has become an integral part of our daily life and it’s use is increasing. In 2013
the worldwide production has reached an all- time high of about 300 million tons
(MT). Single use-packaging account for almost 40%, of the total production. In
Europe the produced volume is about 57 MT (demand 46 MT). In 2012, 25,2 million
tons of post-consumer plastics ended up in the waste upstream. Of this 26% was
recycled while 38% still landed on the landfill [1].
In the past the Life Cycle Assessment (LCA) was linear, after usage it became waste
and ended meanly as landfill. Under consumer and political pressure the EU
presented a green paper in 2013[2] indicating that it has to become a circular
economy. In these economical tough times recycling could create about 160.000 jobs
if the recycling rate goes up to 70% in 2020. But is recycling of this single use
material easy? Modern packaging materials consists of many layers (up to 7 or
more). Each layer has special properties but by physical recycling these properties
are lost. Recyclates are becoming a complex mixture.
Another complex problem is presented in plastics in durable applications, like cars,
electronics, crates and so on. These also have to be recycled but during their
functional life new regulations have been introduced. For instance RoHS (2011/65)
restricts the maximum concentration of toxic heavy metals in electronic applications
(e.g, in end- or consumer products the toxic metal cadmium must not exceed 100
ppm). In the EU several regulations have been developed over the past decades, for
instance REACh. The raw materials of the durable recyclates could be contaminated
with the inheritance of the past, toxic metals are diluted by physical recycling. Is
chemical recycling the future?
Nowadays plastic is found littering the environment in large quantities, especially in
our seas and oceans. The ingestions of plastic by seabirds has been monitored in
stomachs of beached fulmars for more than 30 years. [3]. A reduction of industrial
pellets has been observed but in consumer plastic debris no data exists about the
toxic load of plastic ingested by wildlife. First investigations prove that heavy metals
are present in the plastic fragments.
References
[1] Plastics Europe Web site;
http://issuu.com/plasticseuropeebook/docs/final_plastics_the_facts_2014_19122

Heavy metals in plastic, recycling
and environmental aspects

Heavy metals in plastic, recycling and
environmental aspects
- Plastic a man-made material
-
CARAT
-
CARAT
- Short introduction to plastics
- Recycling of food packaging
-Heavy metals in food packaging
- The problems of physical recycling
- Some examples of plastic recycling
-Plastic in the environmental a big problem

Plastic production is all time high. The use of fossile fuel as
raw
material
and
environmental
issues
makes
the
discussion
of
Introduction: plastic, a man-made material
raw
material
and
environmental
issues
makes
the
discussion
of
an economical very succesfull man-made material hot.

CARAT: Control And Research Analysis Thermoplastics
Carat analyses the standard properties of plastic for
the compounding and injection moulding industry: e.g.
MFR, viscosity and impact strength but also element-
analyses
.
analyses
.
Analysing
the
basic
properties
of
Analysing
the
basic
properties
of
recycled plastic are a challenge.
Furthermore in cooperation with
Shimadzu and IMARES we‘re
trying to describe plastic waste
in the environment.

Short introduction to plastic
In 1907 the first real plastic innovation was introduced:
bakelite.
In1951
the
annual
production
of
plastics
was 1,5
Mt
This are mainly thermoplastics. In contrast to bakelite
thermoplastics have no 3D structure (thermosets and
less rubber) but a 2D structure. The long chains are
more flexible and the material can be remelted:
reused
or
recycled
.
In1951
the
annual
production
of
plastics
was 1,5
Mt
(Million tons). Figures show that in 2013 the annual
production was 299 Mt.
reused
or
recycled
.
This flexiblity explains the
succes of plastics,
especially in single use
food packaging.

Recycling of plastic food packaging
Food packaging is becoming more and more
complex.
.
Industry
is
finding
ways
to
combine
special
.
Industry
is
finding
ways
to
combine
special
properties to reduce thicknes (saving raw
material).
For intance shrink films: modern films are 30
µm thick and can consist out of four (or more)
layers!
Each layer is a special grade modified LLD-PE.
LLD-PE is not found back in
the standard plastic recycling
signs.

Heavy metals in plastic food-packaging
PET is a much used material in food-packaging.
The polymerization of PET is catalysed with
antimony-compounds. But antimony can leak
(
migration
) out
of
polymer
matrix
into
the
beverage
.
(
migration
) out
of
polymer
matrix
into
the
beverage
.
Concentration Sb in tapwater is limited: 5 µg/L.
PET is also used in teabags. Conclusion
release of Sb concentrations can exceed limit
(
Posterpresentation
J. Knoop PS2.51).
(
Posterpresentation
J. Knoop PS2.51).
Recycling of PET bottles is the successtory of
the industry.

Plastic waste: physical recycling the solution?
In the EU plastic-waste is a hot item, in march 2013 the EU commission presented a
Greenbook. Plastic recycling, according to the EU, has the opportunity to create in
Europe more than 160.000 jobs.
We have already seen that
food packaging is
becoming more an more
complex.
Physical recycling isn‘t
simple.Recycling mixes
plastics
:
downcycling
!
plastics
:
downcycling
!
.
Food-packaging is a single
used material but what about
plastic from auto-, electronic
parts or other durable
apllications?

A recycling problem: degradation
In the past, now prohibited, heavy metals were used in plastics as stabilising and
coloring agents. It increased for instance the lifetime.
Thermodynamically
:
carbon
-
backboned
plastics
Thermodynamically
:
carbon
-
backboned
plastics
are meta-stable so by sufficient extra energy, eg.
heat or UV-radiation, the material will degradate.
In this proces heavy metals are released. In the
further presentation are two more heavy metals
discussed: lead (Pb) and cadmium (Cd).
Both
are
nowadays
restricted
by
Both
are
nowadays
restricted
by
for instance REACh (EG
1907/2006) and RoHS
(2011/65/EU)
Cd: max. 100 ppm and Pb max.
1000 ppm

Recycling Plastic: example 1 ABS (ex-electronics)
FTIR-ATR: Virgin (black) vs recycled (red) ABS
(terpolymer of acrylonitril/butadien/styrene)
FTIR Spectra of virgin and post consumer waste. Additional peaks appear, especially
over the region 2000 - 1000 cm-1. The material could be contaminated with
polycarbonate or a brominated flame-retardant.

Recycling Plastic: example 1 ABS (ex-electronics)
EDX-RF analysis gives additional information.
The material contains bromine and antimony.
Antimony is used as a synergist in brominated
flame-retardants.
Furthermore cadmium is found in high
concentrations (limit <100 ppm)
This materiaal is not suitable for
physical recycling: thermal recycling.
(Maybe could chemical recycling bring
a solution in the future.)

Recycling plastic: example 2 PP (ex-automotive)
DSC shows that the
material is conta-
minated
with
PE.
EDX
-
RF
detected
lead
: 1124 ppm.
This
is
minated
with
PE.
The low
concentration PE has
no strong infuence on
the mechanical
properties.
EDX
-
RF
detected
lead
: 1124 ppm.
This
is
above the limit (1000 ppm).
ICP measurement: 724 ppm Pb.
Note: material is mineralfilled (talc 23%), we
assume that the talc disturbs EDX-RF
measurements (callibrated on unfilled
polymers.)

Recycling plastic: example 3 PE/PP (ex-crates)
Material was standard
analyzed with EDX-RF.
High
load
of
cadmium
High
load
of
cadmium
was detected: 2016 ppm.
ICP-OES confirms
EDX results: 2032
ppm Cd
.

Recycling post-consumer plastic
The general problems with recyclates, especially post-consumer, is the unknown history
and composition of the material. For determination of applications of this material many
extra
costly
analysis
are
nesserary
.
extra
costly
analysis
are
nesserary
.
Summary: these extra (control) analysis
make recyclates expensive (even more
than virgin materials from the industry).
This is a big challenge for the EU
and the (recycling-)industry to
overcome.

Plastic a BIG environmental problem
Estimations of the UNEP: annually 6.4 Mt plastic
ends in our seas and oceans worldwide. Plastic in
the environment is a worldwide problem. UV-
Radition
changes
the
chemical
composition
of
In rivers, seas and oceans big plastic parts are mechanically broken by
waves: microplastics are generated (dimensions < 5 mm). Industrial pellets,
the so-called mermaid tears, are also regularly found.
Radition
changes
the
chemical
composition
of
plastic, the material is becoming brittle.

Beached pellets are, especially on the
surface, exposed to UV-radiation, heat and
sand (grinding).
Plastic in the environment, beached
Changes in the surface are visible with FTIR-
ATR.
The big green peak at 1090 cm-1 is typical for
sand (SiO2).
Also yellow pellets (PE) were found on the
beach. The element analysis were
remarkble.
EDX-RF: 3692 ppm Cd
ICP-OES measurements: 3812 ppm Cd

Some plastics, like PE,
PP and EPS, float on
seawater
. Fulmars
Plastic in the environment, eaten
seawater
. Fulmars
mistake floating plas-
tic for food.
Recherche FAE-2011-x35-14
Score (%)
Kunststof
FTIR-ATR analyses of
the unwashed samples
givens a lot of
additional peaks.
Standard
library
search
Score (%)
Kunststof
83,4 PA66/6
82,7 PA HTN
81,7 PA6
Beoordeling Carat: PP
Standard
library
search
results in PA (polyamide
.
The PP pellet is on the
surface contaminated
with food-remains.

Plastic in the environment, eaten
EDX RF is like FTIR-ATR a non destructive method. Plastic stomach content is
also screened on Cd, Pb, Cr, Hg (RoHS EU 2011/65). Some remarkble results:
Red
fragment
:
Red
fragment
:
EDX-RF found Cd: 2171 ppm
Blue fragment
EDX-RF found Pb: 130 ppm

Heavy metals in plastic
Antimony trioxide is possibly a carcinogen to humans. It’s used
in the manufacture of polyester fabrics and PET. Chronic
exposure may cause lung damage, stomach problems, and skin
Lead is considered one of the first anthropogenic environmental
pollutants (Aberg et al., 1999). Two significant sources of the lead
in dust and soil in this country originated in lead-based paint and
leaded gasoline (Mielke et al., 1998a). Exposure to lead comes
with a financial cost as well as a cost to health.
exposure may cause lung damage, stomach problems, and skin
irritation. Antimony is also linked to reproductive problems.
Cadmium: the greatest concern is from exposure to lower
doses over a long period of time. The lower and long-term
exposure to cadmium through air or through diet can cause
kidney damage (formation of kidney stones and affect the
skeleton, which can be painful and debilitating). Lung damage
has also been observed.

Plastic in the environment
Summary
In our modern society heavy metals, packed
in plastic, are found back in recyclates and
environment, even in foodpackaging.
What the health effects are is in this moment
unsure.
Avoid
logistic
chaos
Part of our research, in cooporation with Shimadzu and IMARES, is to
develop a new approach to describe this kind of materials in our man-made
society and environment.
Avoid
logistic
chaos

Thank You

Questions?