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POPS REVIEW COMMITTEE INFORMATION REPOSITORY
POPRC CANDIDATE POPS
Current Proposals
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Currently, there are ten chemical nominations being considered by the POPs Review Committee.
Quick Guide to POPRC Candidates
Joseph DiGangi, PhD
Environmental Health Fund
14 August 2007
 click on this arrow to read data.
 click on this arrow to download a .pdf fact sheet.
Alpha Hexachlorocyclohexane (Alpha HCH)

download as a .pdf fact sheet.
Beta Hexachlorocyclohexane (Beta HCH)

download as a .pdf fact sheet.
Chlordecone

download as a .pdf fact sheet.
Endosulfan

download as a .pdf fact sheet.
Hexabromobiphenyl (HBB)

download as a .pdf fact sheet.
Lindane

download as a .pdf fact sheet.
OctaBDE

download as a .pdf fact sheet.
PentaBDE

download as a .pdf fact sheet.
PeCB

download as a .pdf fact sheet.
PFOS

download as a .pdf fact sheet.
SCCPs

download as a .pdf fact sheet.
Alpha Hexachlorocyclohexane (Alpha
HCH)
Draft Risk Profile May 2007
http://www.pops.int/documents/meetings/poprc/drprofile/drp/DraftRiskProfile_a-HCH.pdf
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Composition
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One of 5 stable HCH isomers in technical
HCH
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Uses
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Alpha-HCH by itself is neither
intentionally produced nor placed on the market but produced as the main
constituent of technical HCH which is used as organochlorine insecticide or
chemical intermediate to manufacture enriched gamma-HCH (Lindane).
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Releases
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Historically, alpha-HCH was released
during the manufacture of technical HCH and its use as a pesticide. Li and
Macdonald (2005) estimated the global usage of alpha-HCH (based on data on
technical HCH) at 6 millions tons, with 4.3 millions tons emitted into the
atmosphere. Releases of alpha-HCH into the environment are also possible from
hazardous waste sites (USEPA, 2006), stockpiles and residues of Lindane
production, which are not always controlled or maintained safely (IHPA,
2006). Also, contaminated sites (e.g. from former production plants) may
contribute to the environmental burden of alpha-HCH (Concha-Grana et al.,
2006). Though no quantitative estimates of these releases exist, the amounts
of HCH residuals in the form of by-products from Lindane production are
assumed to range between 1.6 - 1.9 to 4.8 million tons.
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Fate
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Degradation is very slow especially at
lower temperatures. Half-lives for alpha-HCH in Arctic lakes were up to 1.4
years, whereas in the Eastern Arctic Ocean enantioselective degradation
resulted in a range of approximately 5 to 17 years. High levels are found in
Arctic biota because of the bioaccumulation potential of alpha-HCH (as a
product of bioconcentration and biomagnification) and the historically
particularly efficient deposition processes of this substance in the Arctic
waters. The efficient accumulation is an effect of the combination of the
physico-chemical properties of alpha-HCH and the low temperature in the Arctic. In other words, alpha-HCH effectively
accumulates in the Arctic ecosystem as a whole.
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Effects
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Alpha-HCH has been shown to be
neurotoxic, hepatotoxic, and to cause immunosuppressive effects and cancer in
laboratory animals. The International Agency for Research on Cancer (IARC)
has classified alpha-HCH in group 2B, possibly carcinogenic to humans.
Several epidemiological studies indicate that alpha-HCH might play a role in
human breast cancer. Alpha-HCH is a known tumour promoting agent. Alpha-HCH
may adversely affect human health in contaminated areas as well as in Arctic
regions. Based on the available toxicity data of alpha-HCH, it can be
concluded that current concentrations of alpha-HCH in food and human breast
milk are a matter of concern. The estimated daily intake of alpha-HCH of
Arctic indigenous people exceeds safe intake reference values, even though
estimation is very conservative. Compared with a general accepted risk of one
case per million, this risk seems unacceptably high. Nevertheless it should
be emphasized that traditional foods have unique social, cultural, spiritual
and economic value and therefore it is strongly recommended to avoid
alpha-HCH levels of concern. Human exposure to alpha-HCH results mostly from
ingestion of contaminated plants, animals and animal products. Monitoring
data from a wide range of biota including humans suggest that significant
uptake from the environment occurs, which demonstrates the bioavailability of
alpha-HCH. Monitoring data show its ubiquitous distribution in all
environmental media
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Exposure
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Human exposure to alpha-HCH results
mostly from ingestion of contaminated plants, animals and animal products.
Monitoring data from a wide range of biota including humans suggest that
significant uptake from the environment occurs, which demonstrates the
bioavailability of alpha-HCH. Monitoring data show its ubiquitous distribution
in all environmental media
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Status
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Technical HCH is listed in Annex II of
the 1998 Aarhus Protocol on Persistent Organic Pollutants (POPs) under the
Convention on Long-Range Transboundary Air Pollution which restricted alpha-HCH
use to an intermediate in chemical manufacturing only. HCH (mixed isomers) is
subject to the PIC Procedure of the Rotterdam Convention and is listed in
Annex III of the Convention. In the European Union, the production and use of
technical HCH as an intermediate in chemical manufacturing will be phased out
by the end of 2007 at the latest (Regulation (EC) No 850/2004). HCHs are also
among the priority substances (Decision No 2455/2001/EC) of the adopted EU
Water Framework Directive 2000/60/EC. Hexachlorocyclohexane isomers, including
the alpha-isomer, are on the List of Chemicals for Priority Action under the
OSPAR Commission for the Protection of the Marine Environment of the Northeast Atlantic.
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Alternatives
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Will be discussed together with Lindane
in Annex F evaluation if Alpha HCH advances.
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Beta Hexachlorocyclohexane (Beta
HCH)
Draft Risk Profile May 2007
http://www.pops.int/documents/meetings/poprc/drprofile/drp/DraftRiskProfile_b-HCH.pdf
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Composition
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One of 5 stable HCH isomers in technical
HCH at levels of 5 – 14%.
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Uses
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Beta-HCH
by itself is neither intentionally produced nor placed on the market. It is
produced as constituent of technical HCH used as organochlorine insecticide
or chemical intermediate to manufacture enriched HCH (lindane). Currently no
production data on technical HCH have been reported, whereas manufacture of
lindane still takes place (IHPA, 2006).
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Releases
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Around 10 million tons
of technical HCH were released to the environment between 1948 and 1997 (Li
et al. 1999). According to Li and Macdonald (2005) global usage of technical
HCH was dominated by 10 countries headed by China, which consumed almost half
of the total global quantity. The other countries were (in order of
decreasing usage): Former Soviet Union, India, France,
Egypt, Japan, United
States, East Germany,
Spain and Mexico.
Historically beta-HCH was released during the manufacture of technical HCH
and its use as a pesticide. Li et al. (2003) estimated global emissions of beta-HCH from
the usage of technical HCH between 1945 and 2000 at 850 000 tons, of which
230 000 tons were emitted into the atmosphere over the same period. As a
result of the ban on technical HCH in northern countries, global emissions of
beta-HCH have undergone a “southward tilt” (Li et al., 2003). Releases of
beta-HCH into the environment are also possible from hazardous waste sites
(USEPA, 2006), stockpiles and residues of lindane production, which are not always
controlled or maintained safely (IHPA, 2006). Also, contaminated sites (e.g.
from former production plants) may contribute to the environmental burden of
beta-HCH (Concha-Grana et al., 2006).
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Fate
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Abiotic degradation processes do not play an
important role in the fate of beta-HCH in the environment. Thus photolysis
and hydrolysis are not significant. Under favourable
conditions, beta-HCH is susceptible to biodegradation. However compared to
the gamma- and alpha-HCH it is the most recalcitrant isomer. Laboratory and
field data including a long-term soil study suggest that beta-HCH is
persistent in soil, especially under low temperatures. It is mainly
associated with particles and has a low leaching potential. The
physico-chemical properties of beta-HCH allow the dispersal of the substance
from its sources to the Arctic mainly by
long-range environmental transport via ocean currents. Beta-HCH has been
detected in the Arctic Ocean and is present
in marine, terrestrial species, and humans.
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Effects
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Beta-HCH
is acutely toxic to aquatic organisms and shows estrogenic effects in fish.
Reduced fitness of offspring in birds as well as reduced retinol
concentrations in polar bears is associated with beta-HCH and HCHs levels.
Toxicological studies with beta-HCH have demonstrated neurotoxicity and hepatotoxicity.
Also reproductive and immunosuppressive effects and effects on fertility were
seen in laboratory animals. Beta-HCH has been classified in group 2B as possibly
carcinogenic to humans by the International Agency on Research and
Cancer (IARC). Several epidemiological studies indicate that
beta-HCH might play a role in human breast cancer.
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Exposure
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Beta-HCH
exposure levels in local areas have declined after worldwide prohibitions and
restrictions. However regions with recent exposure and/or high pollution can
still show elevated levels. A special concern also arises from exposure of
hazardous waste sites and dumping grounds from disposed beta-HCH residues
from lindane production. Due to its persistence beta-HCH can still be
detected at low background levels in all environmental media except in
regions with recent usage and/or high pollution. Data from the abiotic
environment in the Arctic are scarce partly
due to low levels compared with the other HCH isomers. In contrast to this
fact fairly high concentrations in Arctic biota including marine mammals and
birds were detected with increasing levels. Beta-HCH is present in
terrestrial and aquatic food chain. Beta-HCH may bioaccumulate and biomagnify
in biota and Arctic food webs, especially in
upper trophic levels. In humans accumulation in fat tissue and high
concentrations in blood and in breast milk may occur. Beta-HCH transfers from
mothers to embryos and nursing infants. Human exposure to beta-HCH results
mostly from ingestion of contaminated plants, animals and animal products.
High exposure is expected in contaminated areas due to extensive use, former
production, disposal sites and stockpiles. Based on the hazard profile and
the exposure levels in the environment including the food chain, it can be
concluded that beta-HCH may adversely affect wildlife and human health in
contaminated regions. Arctic public health authorities believe the significant
social, cultural and economic benefits of traditional foods outweigh the
risks of contaminants such as HCH at present but give another reason for the
quick control and elimination of all HCH isomers from traditional foods.
However based on levels found in the Arctic region, it can be also concluded
that beta-HCH can lead to significant adverse human and environmental effects
as a result of its long-range environmental transport.
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Status
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Technical HCH is listed in Annex II of
the 1998 Aarhus Protocol on Persistent Organic Pollutants (POPs) under the
Convention on Long-Range Transboundary Air Pollution which restricted alpha-HCH
use to an intermediate in chemical manufacturing only. HCH (mixed isomers) is
subject to the PIC Procedure of the Rotterdam Convention and is listed in
Annex III of the Convention. Canada, Mexico,
and the United States
signed the North American Regional Action Plan (NARAP) on Lindane and Other
Hexachlorocyclohexane Isomers in 2006 with the goal of reducing the risks
associated with the exposure of humans and the environment to lindane and
other HCH isomers. In the European Union the production and use of technical
HCH as an intermediate in chemical manufacturing will be phased out by the
end of 2007 at the latest (Regulation (EC) No 850/2004). HCHs are also one of
the priority substances (Decision No 2455/2001/EC) of the adopted EU Water
Framework Directive 2000/60/EC. Hexachlorocyclohexane isomers, including the
beta-isomer, are on the List of Chemicals for Priority Action under the OSPAR
Commission for the Protection of the Marine Environment of the Northeast Atlantic.
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Alternatives
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Will be discussed together with Lindane
in Annex F evaluation if Beta HCH advances.
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Chlordecone
Draft Risk Management Evalution May 2007
http://www.pops.int/documents/meetings/poprc/drprofile/drme/DraftRME_Chlordecone.pdf
Risk Profile UNEP/POPS/POPRC.2/17/Add2
http://www.pops.int/documents/meetings/poprc_2/meeting_docs/report/POPRC-2%20rep%20add2.pdf
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Composition
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Synthetic chlorinated organic compound
also known as Kepone, GC-1189, Merex, ENT 16391, and Curlone. Chlordecone is closely related chemically
to mirex, a pesticide which is already listed under the Stockholm Convention. The chemical
structure of chlordecone differs from mirex in that the oxygen of the keto
group in chlordecone is replaced by two chlorine atoms in mirex.
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Uses
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Based on the available information,
Chlordecone is not anymore produced or used. Chlordecone has been used in
various parts of the world for the control of a wide range of pests. In
particular, Chlordecone has been used extensively in the tropics for the control
of banana root borer. It has been used as a fly larvicide, as a fungicide
against apple scab and powdery mildew and to control the Colorado potato
beetle, rust mite on non-bearing citrus, and potato and tobacco wireworm on
gladioli and other plants. Chlordecone has also been used in household
products such as ant and roach traps. Chlordecone was also found to be
present in technical grade mirex.
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Releases
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Given
the specific pesticidal uses of Chlordecone, it can be expected that all
amounts manufactured are ultimately released to the environment. The use of Chlordecone
as a pesticide in Martinique and Guadeloupe
until 1993, resulted in severe contamination of soil and surface water, which
are being monitored at present. (Bocquene & Franco, 2005, Beaugendre,
2005). Major releases of Chlordecone occurred to the air, surface waters, and
soil surrounding a major American manufacturing site in Hopewell, Virginia.
Releases from this plant ultimately contaminated the water, sediment, and
biota of the James River, a tributary to the Chesapeake
Bay (Quoted from US ATSDR, 1995).
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Fate
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Chlordecone
is not expected to hydrolyse or biodegrade in aquatic environments, nor in
soil. Direct photodegradation is not significant. Therefore, Chlordecone is
considered to be highly persistent in the environment. Chlordecone is
considered to have a high potential for bioaccumulation and biomagnification.
Due to lack of monitoring data on chlordecone, the assessment of the
potential for long-range transport of chlordecone was based on
physico-chemical properties and application of long range transport models.
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Effects
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Chlordecone
is readily absorbed into the body and accumulates following prolonged
exposure. The pesticide is both acutely and chronically toxic, producing
neurotoxicity, immunotoxicity, reproductive, musculoskeletal and liver
toxicity at doses between 1 - 10 mg/kg bw/day in experimental animal studies.
Liver cancer was induced in rats at a dose of 1 mg/kg body weight per day,
and reproductive effects are seen at similar dose levels. The International
Agency for Research on Cancer has classified chlordecone as a possible human
carcinogen (IARC group 2B). Moreover, chlordecone is very toxic to aquatic
organisms, with the most sensitive group being the invertebrates.
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Exposure
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The
available information regarding environmental concentrations of Chlordecone
is very limited and includes only areas in the vicinity of production (US) or use (Martinique).
Recent monitoring data from the United States
demonstrate the persistence of Chlordecone, known as Kepone in the United States.
In Martinique, the widespread use of
Chlordecone until 1993 has resulted in contamination of soils and surface
water in most of the island (Bocquené & Franco, 2005). \
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Status
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Chlordecone
is listed in Annex I of the Protocol to the Convention on Long-Range
Transboundary Air Pollution (CLRTAP) on Persistent Organic Pollutants. The
provisions of the Protocol oblige Parties to phase out all production and
uses of Chlordecone. Chlordecone is also included in the Convention for the
Protection of the Marine Environment of the North-East
Atlantic (OSPAR Convention) as a substance of possible concern[1]. Under the Convention on the
Protection of the Marine Environment of the Baltic Sea Area (HELCOM Convention)
Chlordecone is listed as selected substances for immediate priority action (Recommendation 19/5,
Attachment, Appendix 3) and is scheduled for elimination (Annex I, part 2). HELCOM aims to move towards the target
of the cessation of discharges, emissions and losses of hazardous substances
by the year 2020.
Under the Basel Convention off-specification or out-dated pesticides, without
specific mention of Chlordecone, are classified as hazardous in Annex VIII.
Chlordecone is currently not listed in the Rotterdam Convention on the Prior
Informed Consent Procedure for certain hazardous Chemicals and Pesticides in
international trade. Thailand
has submitted a notification of Final Regulatory Actions for Banned or
Severely Restricted Chemicals that has been verified to meet the requirements
of Annex I of the Rotterdam Convention.
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Alternatives
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A variety of chemical alternatives have been
utilised including ethoprop, oxamyl, cyfluthrin, imidacloprid,
azadirachtin, bifenthrin, boric acid, carbaryl, capsaicin, cypermethrin,
cyfluthrin, deltamethrin, diazinon, dichlorvos, esfenvalerate, imidacloprid,
lamda-cyhalothrin, malathion, permethrin, piperonyl butoxide, pyrethrins,
pyriproxyfen, resmethrin, s-bioallerthrin, tetramethrin, aldicarb,
isophenphos, phenamiphos, cadusaphos, terbuphos. Alternatives to chlordecone
also include non-chemical agroecological methods, such as preventative pest
management through appropriate fertility and field sanitation practices that
reduce pest pressure; the use and habitat enhancement of natural enemies;
microbial preparations such as Bacillus
thuringiensis; cultural practices such as crop rotation, intercropping,
and trap cropping; barrier methods, such as screens, and bagging of fruit;
use of traps such as pheremone and light traps to attract and kill insects.
These and other agroecological methods are being extensively and successfully
practised in many countries, eliminating the need for Chlordecone or other
chemical interventions.
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Endosulfan
Proposal by the European Union August 2007
http://www.pops.int/documents/meetings/poprc/docs/chem_review.htm
Supporting information by German Federal
Environment Agency
http://www.pops.int/documents/meetings/poprc/docs/under_review/endosulfan/Draft%20Dossier_endosulfan.pdf
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Composition
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There are four relevant forms of
endosulfan: alpha endosulfan, beta endosulfan, endosulfan sulphate, and
technical endosulfan which is a 2:1 to 7:3 mixture
of the alpha and beta isomers.
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Uses
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Insecticide for control of aphids,
thrips, beetles, foliar feeding larvae, mites, borers, cutworms, bollworms,
whiteflies, and leafhoppers. Used on cotton, tobacco, cantaloupe, tomatoes,
squash, eggplant, sweet potato, broccoli, pears, pumpkins, corn, cereals,
oilseeds, potatoes, tea, coffee, cacao, soybean, and other vegetables.
Historically used to control termites and tsetse fly. Used in some countries
in the past as a wood preservative.
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Releases
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The
vast majority of endosulfan is used as active ingredient of plant protection
products. That means it is deliberately spread over large soil or plant
areas. Worldwide production estimated at 10,000
metric tonnes, however, current global production is
likely to be significantly higher as use remains widespread. Recently the
GAPS study, a global monitoring project on POPs, revealed that endosulfan
“showed highest values of all the organochlorine pesticides (OCPs)
investigated, in the range of tens to hundreds of pg/m³, with a geometric
mean of 58”. Endosulfan was also among those organochlorine chemicals which
were present in highest concentrations worldwide in samples from tree bark
lipids. Unlike for more volatile compounds no significant correlation with
geographical latitude was found. The authors concluded that these compounds
are not as effectively distilled and tend to remain near the original region
of use.
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Fate
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In the environment, endosulfan is
oxidized in plants and in soils to form primarily endosulfan sulfate and
endosulfan-diol. Formation of endosulfan sulfate is mediated essentially by
micro-organisms, while endosulfan-diol was found to be the major hydrolysis
product. Endosulfan was measured repeatedly in Arctic seawater during the
1990s. Mean concentrations were similar to those of chlordane. Concentrations
of endosulfan from Arctic air monitoring stations increased from early to
mid-1993 and remained at that level through the end of 1997. Reported values
for measured bio-concentration factors of endosulfan in various aqueous
organisms cover a wide range from 100 in oysters to 11,000 in whole fish. Half-lives
in acidic to neutral soils range from one to two months for α-endosulfan
and from three to nine months for β-endosulfan under aerobic condition.
The estimated half-lives for the combined toxic residues (endosulfan+
endosulfan sulfate) ranged from roughly 9 months to 6 years. Anaerobic
conditions may considerably extend half-lives in soils.
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Effects
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The oxidised metabolite, endosulfan sulfate, shows an acute
toxicity similar to that of the parent compound. In contrast, endosulfan-diol, which is
another metabolite of endosulfan, is found substantially less toxic to fish
by about three orders of magnitude. Recent literature has indicated the
potential for endosulfan to cause some endocrine disruption in both
terrestrial and aquatic species. Effects observed were impaired development
in amphibians, reduced cortisol secretion in fish,
impaired development of the genital tract in birds and hormone levels,
testicular atrophy and reduced sperm production in mammals. Excessive and
improper application and handling of endosulfan have been linked to
congenital physical disorders, mental retardations and deaths in farm workers
and villagers in developing countries in Africa, southern Asia and Latin America. Endosulfan was found among the most
frequently reported intoxication incidents, adding unintentionally further evidence
to its high toxicity for humans. In laboratory animals, endosulfan produces
neurotoxicity effects, which are believed to result from over-stimulation of
the central nervous system. It can
also cause haematological effects and nephrotoxicity.
The α-isomer was generally found more toxic than the
β-isomer.
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Exposure
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Endosulfan was detected in adipose tissue and blood of polar bears
from Svalbard. Endosulfan has also been
detected in blubber of minke whale and in liver of
northern fulmar. Endosulfan was detected in all lake trout examined from
isolated Ontario (Canada)
and New Brunswick
lakes.
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Status
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Endosulfan
has been included in the OSPAR List of Chemicals for Priority Action (update 2002). Endosulfan is on the list of priority
substances agreed by the Third North Sea Conference (Annex 1A to the Hague
Declaration). The second meeting of the Chemical
Review Committee agreed to recommend to the Conference of the Parties that
endosulfan should be listed in Annex III of the Rotterdam Convention and
developed a rationale setting out how the criteria in Annex II had been met.
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Alternatives
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Will be discussed in Annex F
evaluation if Endosulfan advances.
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Hexabromobiphenyl (HBB)
Draft Risk Management Evaluation May 2007
http://www.pops.int/documents/meetings/poprc/drprofile/drme/DraftRME_HBB.pdf
Risk Profile UNEP/POPS/POPRC.2/17/Add3
http://www.pops.int/documents/meetings/poprc_2/meeting_docs/report/POPRC-2%20rep%20add3.pdf
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Composition
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Hexabromobiphenyl belongs to a
wider group of polybrominated biphenyls (PBBs). The term “polybrominated
biphenyls” or “polybromobiphenyls” refers to a group of brominated
hydrocarbons formed by substituting hydrogen with bromine in biphenyl. The
hexabromo congeners exist as 42 possible isomeric forms. Trade names include
FireMaster BP-6 and FireMaster FF-1. The commercial production of PBBs began in
1970. Approximately 6 million kg of PBBs were produced in the United States
from 1970 to 1976. Production and use of hexabromobiphenyl has ceased in
most, if not all, countries. However, it is possible that hexabromobiphenyl
is still being produced in some developing countries or in countries with
economies in transition.
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Uses
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Hexabromobiphenyl
has been used as a fire retardant in acrylonitrile-butadiene-styrene (ABS) thermoplastics
for constructing business, machine housings and in industrial and electrical
products and in polyurethane foam for auto upholstery. A considerable part of the
substance produced will probably reach the environment sooner or later
because of the high stability of these compounds.
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Releases
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Data for
loss into the environment during normal production are published only for the
United States.
In 1973, an accidental release of PBBs occurred in Michigan (referred to as
the "Michigan disaster" in EHC 152), when two products manufactured
by the Michigan Chemical Company were inadvertently confused and 250-500 kg (Di Carlo et. al.,
1978) of FireMaster(R), instead of NutriMaster(R), a
magnesium oxide-based cattle feed supplement, were added to animal feed and
distributed to farms within the state. This accidental mix up resulted in
widespread contamination by PBBs. Approximately 5350 tonnes of
hexabromobiphenyl were used in commercial and consumer products in the United States,
most in the production of plastic products with an estimated use life of 5–10
years (Neufeld et. al., 1977). Since the cessation of production, all
of these products, such as TV cabinet and business machine housings, are
expected to have been disposed of by land filling or incineration (Neufeld et
al., 1977)
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Fate
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According
to available data, hexabromobiphenyl can be considered to be highly
persistent in the environment. There is evidence of low or no degradation in
water, soil and sediment, in the laboratory as well as in the field. Hexabromobiphenyl is less volatile than
many of the currently listed POP substances. However, extensive data on
monitoring shows that it is found throughout the Arctic wildlife, demonstrating
that it does have a high potential for long range environmental transport. With
measured weight-based BCF values in the range 4,700-18,100 and
biomagnification factors in the aquatic food chain exceeding 100,
hexabromobiphenyl is considered to be highly bioaccumulative and to have a
high potential for biomagnification. These properties are demonstrated by
several authors to be comparable to those of hexachlorobiphenyl (a PCB
compound), for which the bioaccumulative properties are well documented.
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Effects
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Hexabromobiphenyl
is readily absorbed into the body and accumulates following prolonged
exposure. Although the acute toxicity of hexabromobiphenyl is low, a number
of chronic toxic effects including hepatotoxicity have been observed in
experimental animals at doses around 1 mg/kg bw/day following long-term exposure,
and effects are seen in the rat thyroid at doses as low as 0.05 mg/kg bw/day.
The International Agency for Research on Cancer has classified hexabromobiphenyl
as a possible human carcinogen (IARC group 2B). The PBBs are endocrine
disrupting chemicals, and effects are seen on reproductive capacity in rats,
mink and monkeys. There is epidemiological evidence of hypothyroidism in
workers exposed to polybrominated biphenyls and of
increased incidence of breast cancer in exposed women. Data on
toxicity to other species than laboratory mammals is scarce but suggests the
environmental toxicity of hexabromobiphenyl is comparable to that of
hexachlorobiphenyl.
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Exposure
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Recent monitoring data in soil, water and sediments
for PBBs are limited. Historical monitoring data from the United States
indicate that environmental PBB concentrations are confined to areas near
former manufacturing facilities and regions of Michigan affected by the farm
accident of the early 1970's (see Section 2.2.3) (US ATSDR, 2004). The only available data for environmental
concentrations of PBBs in areas outside the vicinity of former production
sites are those from sediment samples from Greenland
(Vorkamp et. al., 2004), where PBBs (including PBB 153) were not
detected in any sample (the limits of detection/quantification are, however,
not well defined in the paper). The US ATSDR (2004), considers the current
human exposure to PBBs to be very low, because PBBs are no longer
produced or used. Thus, the general population exposure to PBBs will only be
from historical releases. For people residing in the lower peninsula of Michigan, especially
in the immediate vicinity of the PBB contaminated areas of this region,
exposure to PBBs may still be occurring today. However, environmental levels
have decreased since the 1970s and current exposure, if any, will be at low
levels. For other regions of the United States,
the levels of exposure will either be very low or none (Quoted from US ATSDR,
2004)/ In Arctic and North Atlantic regions,
where the traditional diet includes top predators (e. g. seal in
Greenland and pilot whale in the Faroe Islands),
exposure has not ceased. Especially the level of PBBs in pilot whale blubber
of up to 17 µg/kg lipid indicate the presence of hexabromobiphenyl in food.
Pilot whale blubber is consumed as a delicacy in the Faroe
Islands.
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Status
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Hexabromobiphenyl is listed in Annex A of the Protocol
to the Convention on Long-range Transboundary Air Pollution (CLRTAP) on
Persistent Organic Pollutants. The provisions of the Protocol oblige Parties
(currently 25) to phase out all production and uses of hexabromobiphenyl. Hexabromobiphenyl, together with other PBBs,
is also included in the UNEP/FAO Rotterdam Convention on the Prior Informed
Consent Procedure for Certain Hazardous Chemicals and Pesticides in
International Trade. Under the Helsinki Convention on the Protection of the
Marine Environment of the Baltic Sea Area (HELCOM[3]) hexabromobiphenyl is listed as a
selected substance for immediate priority action (Recommendation 19/5,
Attachment, Appendix 3) and is scheduled for elimination (Annex I, part 2).
HELCOM aims to
move towards the target of the cessation of discharges, emissions and losses
of hazardous substances by the year 2020. Under the Basel Convention, PBBs are
classified as hazardous in Annex VIII without further specification. SAICM
does not specifically address Hexabromobiphenyl but includes POPs as a class
of chemicals that might be prioritized for assessment and related studies.
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Alternatives
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The
hexabromobiphenyl risk profile describes three principal commercial products
that contained hexabromobiphenyl in the USA
and Canada:
1) acrylonitrile-butadiene-styrene (ABS) thermoplastics
used for business machine housings and electrical products such as radio and
TV; 2) fire retardant in cable coatings and lacquers, and 3) fire retardant
in polyurethane foam for auto upholstery. A number of reports on risk
assessment of alternative substances and processes are available. The OSPAR
priority substances Series (OSPAR, 2001) provides summary information on
alternatives for brominated flame retardants. The Danish Environmental
Protection Agency has described alternative halogen-free flame retardants for
a variety of uses including epoxy, phenolic resins, rigid and soft
polyurethane foam, textiles, and a variety of plastics including ABS (Danish
EPA, 1999). Both drop-in chemical substitutes and alternative materials are
listed. US
EPA has described process alternatives and chemical substitutes for
polyurethane foam (USEPA, 2005). The German Federal Ministry of Environment
has reported on alternatives for flame retardants used in electronics,
upholstery, and other sectors (BMU, 2000). As brominated flame retardants
only account for about 15% of the global flame retardant consumption,
principally a large number of compounds may be considered as alternatives
(OSPAR, 2001). Substitution can take place at three levels: 1) brominated
flame retardants can in some applications be replaced by another flame
retardant without changing the base polymer; (major group of substitutes); 2)
the plastic material, i.e. the base polymer containing flame retardants and
other additives, can be replaced by another plastic material; (e.g.
polysulfone, polyaryletherketone and polyethersulfone) 3) a different product
can replace the product, e.g. the plastic material is replaced by another
material (e.g. wool), or the function can be fulfilled by the use of a
totally different solution.
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Lindane
Draft Risk Management Evaluation May 2007
http://www.pops.int/documents/meetings/poprc/drprofile/drme/DraftRME_Lindane.pdf
Risk Profile UNEP/POPS/POPRC.2/17/Add4
http://www.pops.int/documents/meetings/poprc_2/meeting_docs/report/POPRC-2%20rep%20add4.pdf
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Composition
|
Lindane is the common name for the gamma isomer of
1,2,3,4,5,6-hexachlorocyclohexane (HCH). It is one of 5 stable HCH isomers in
technical HCH. The gamma isomer is the only isomer showing strong
insecticidal properties. The production of lindane is inefficient as for each
ton of Lindane (gamma isomer) obtained, approximately 6-10 tons of other
isomers are also obtained (IHPA, 2006).
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Uses
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Lindane has been used as a broad-spectrum insecticide for seed and
soil treatment, foliar applications, tree and wood treatment and against
ectoparasites in both veterinary and human applications. In the last years the production
of lindane has rapidly decreased and it appears that only Romania and India are current producing
countries. If the estimate of global usage of lindane
of 600,000 tons between 1950 and 2000 is accurate, the total amount of possible
residuals (if it is assumed that a mean value of 8 tons of waste isomers are
obtained per ton of lindane produced) amounts to possibly 4.8 million tons of
HCH residuals that could be present worldwide giving an idea of the extent of
the environmental contamination problem (IHPA, 2006). Air releases of lindane
can occur during the agricultural use or aerial application of this
insecticide, as well as during manufacture or disposal. Also, lindane can be
released to air through volatilization after application (Shen et al., 2004).
Evaporative loss to air from water is not considered significant due to
lindane’s relatively high water solubility (WHO/Europe, 2003).
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Releases
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Considering every ton of lindane produced generates approximately
6 - 10 tons of other HCH isomers, a considerable amount of residues was
generated during the manufacture of this insecticide. For decades, the waste
isomers were generally disposed of in open landfills like fields and other
disposal sites near the HCH manufacturing facilities. After disposal,
degradation, volatilization, and run off of the waste isomers occurred
(USEPA, 2006). If the estimate of global usage of lindane of 600,000 tons
between 1950 and 2000 is accurate, the total amount of possible residuals (if
it is assumed that a mean value of 8 tons of waste isomers are obtained per
ton of lindane produced) amounts to possibly 4.8 million tons of HCH
residuals that could be present worldwide giving an idea of the extent of the
environmental contamination problem (IHPA, 2006). Air releases of lindane can
occur during the agricultural use or aerial application of this insecticide,
as well as during manufacture or disposal. Also, lindane can be released to
air through volatilization after application (Shen et al., 2004). Evaporative
loss to air from water is not considered significant due to lindane’s
relatively high water solubility (WHO/Europe, 2003).
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Fate
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Once released into the environment,
lindane can partition into all environmental media. Hydrolysis and photolysis
are not considered important degradation pathways and reported half-lifes in
air, water and soil are: 2.3 days, 3-300 days and up to 2 to 3 years, respectively. A half-life of 96
days in air has also been estimated. Lindane can bio-accumulate easily in the
food chain due to its high lipid solubility and can bio-concentrate rapidly
in microorganisms, invertebrates, fish, birds and mammals. The bioconcentration factors in
aquatic organisms under laboratory conditions ranged from approximately 10 up
to 4220 under field conditions, the bioconcentration factors ranged from 10
up to 2600. Although lindane may bioconcentrate
rapidly, bio-transformation, depuration and elimination are also relatively
rapid, once exposure is eliminated.
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Effects
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Hepatotoxic, immunotoxic, reproductive and developmental effects
have been reported for lindane in laboratory animals. The US EPA has
classified lindane in the category of “Suggestive evidence of
carcinogenicity, but not sufficient to assess human carcinogenic potential”. The
most commonly reported effects associated with oral exposure to gamma-HCH are
neurological. Most of the information is from case reports of acute gamma-HCH
poisoning. Seizures and convulsions have been observed in individuals who
have accidentally or intentionally ingested lindane in insecticide pellets,
liquid scabicide or contaminated food (WHO/Europe, 2003). Lindane is highly
toxic to aquatic organisms and moderately toxic to birds and mammals
following acute exposures. Chronic effects to birds and mammals measured by
reproduction studies show adverse effects at low levels such as reductions in
egg production, growth and survival parameters in birds, and decreased body
weight gain in mammals, with some effects indicative of endocrine disruption.
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Exposure
|
Lindane can be found in all environmental
compartments, and levels in air, water, soil sediment, aquatic and
terrestrial organisms and food have been measured worldwide. Humans are
therefore being exposed to lindane as demonstrated by detectable levels in
human blood, human adipose tissue and human breast milk in different studies
in diverse countries. Exposure of children and pregnant women to lindane are
of particular concern. Gamma-HCH has been found in human maternal adipose
tissue, maternal blood, umbilical cord blood and breast milk. Lindane has
also been found to pass through the placental barrier. Direct exposure from the use of
pharmaceutical products for scabies and lice treatment should be of concern. Exposure from food sources is possibly of concern for high animal
lipid content diets and subsistence diets of particular ethnic groups (USEPA,
2006 and CEC, 2005). Occupational exposure at manufacturing facilities should
be of concern, because lindane production implies worker exposure to other
HCH isomers as well, for example the alpha isomer is considered to be a
probable human carcinogen (USEPA, 2006).
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Status
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Lindane is listed as a “substance scheduled
for restrictions on use” in Annex II of the 1998 Protocol on Persistent
Organic Pollutants of the Convention on Long-Range Transboundary Air
Pollution. This means that products in which at least 99% of the HCH isomer
is in the gamma form (i.e. lindane, CAS: 58-89-9) are restricted to the
following uses: 1. Seed treatment. 2. Soil applications directly followed by
incorporation into the topsoil surface layer 3. Professional remedial and
industrial treatment of lumber, timber and logs. 4. Public health and
veterinary topical insecticide. 5. Non-aerial application to tree seedlings,
small-scale lawn use, and indoor and outdoor use for nursery stock and
ornamentals. 6. Indoor industrial and residential applications. All
restricted uses of lindane shall be reassessed under the Protocol no later
than two years after the date of entry into force. The Protocol entered into
force on October 23th,
2003.
Lindane, as well as the mixture of HCH isomers, is listed in Annex III of the
Rotterdam Convention on the Prior Informed Consent Procedure as “chemicals
subject to the prior informed consent procedure”.
Hexachlorocyclohexane isomers, including Lindane, the gamma isomer, are
included in the List of Chemicals for Priority Action (Updated 2005) under
the OSPAR Commission for the Protection of the Marine Environment of the Northeast Atlantic.
HCH (including lindane) is listed as a Level II substance in the Great Lakes
Binational Toxics Strategy between the United
States and Canada, which means that one of
the two countries has grounds to indicate its persistence in the environment,
potential for bioaccumulation and toxicity.
Lindane is also listed under the European Water Framework Directive. This
Directive is a piece of water legislation from the European Community. It
requires all inland and coastal water bodies to reach at least “good status”
by 2015. Lindane is
one of the listed priority hazardous substances for which quality standards
and emission controls will be set at EU level to end all emissions within 20
years. Lindane is banned for use in
52 countries, restricted or severely restricted in 33 countries, not
registered in 10 countries, and registered in 17 countries (CEC, 2006).
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Alternatives
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Chemical and non-chemical
alternatives for the agricultural, veterinary and pharmaceutical uses of
lindane in the United States,
Canada and Mexico have
been reviewed in the North American Regional Action Plan on Lindane and Other
HCH Isomers developed by the North American Commission for Environmental
Cooperation (CEC, 2006). Among cultural methods currently known to
effectively prevent harm to seeds and crops are: Crop rotation (alfalfa,
soybeans and clover), where small grains need to be rotated with a non-host
species every year to reduce the severity of infestation and maintain low
levels of pests; Site selection and monitoring in order to determine if
wireworms are present; Fallowing, starving wireworms by allowing the area to
fallow for a few years before planting; Re-seeding with resistant crops such
as buckwheat or flax; Timing of seeding and planting, trying to plant in
warm, dry conditions, usually later in the season for small grains where
larvae are deeper in the soil and giving seedlings a greater chance of
survival; Shallow cultivation to starve hatchlings, expose eggs for predation
and damage larvae; and Soil packing to impede wireworm travel (CEC, 2006). Biological methods are also considered as
non-chemical alternatives to lindane. Current research at Pacific Agri-Food
Research Centre, in Canada
is examining the use of Metarhizium
anisopliae, an insect fungal pathogen to control wireworm. Additional
biological control methods employed in Costa Rica include Trichodama spp, Piper aduncum, Trichogram wasps, and Bacillus thuringiensis (Annex F
information provided by IPEN, 2007).
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OctaBDE
Draft Risk Profile May 2007
http://www.pops.int/documents/meetings/poprc/drprofile/drp/DraftRiskProfile_OctaBDE.pdf
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Composition
|
Commercial mixture contains bromodiphenyl
ethers including: hexa/penta (1.4 – 12%), hepta (43 – 58%), octa (26 – 35%),
nona (8-14%), and deca (0 – 3%). Always used in conjunction with antimony
trioxide.
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Uses
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Flame retardant primarily used in acrylonitrile-butadiene-styrene
(ABS) polymers at 12-18% weight loadings in the final product. Other
minor uses, accounting for the remaining 5% use, include high impact polystyrene
(HIPS), polybutylene terephthalate (PBT) and polyamide polymers, at typical
loadings of 12- 15% weight in the final product. The flame retarded polymer
products are typically used for the housings of office equipment and business
machines. Other uses that have been reported for octabromodiphenyl ether
include nylon and low density polyethylene (WHO, 1994), polycarbonate,
phenol-formaldehyde resins and unsaturated polyesters (OECD, 1994) and in
adhesives and coatings (WHO, 1994).
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Releases
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Although there are some figures on annual production of this
mixture, there are no accurate values on the amount of the commercial octa
and/or the individual homologues in articles in service and disposed at the
world-wide level, but considering the estimated figure of 6 000 tonnes/year
(WHO, 1994) the total amount should be expected in the 105 – 106 tonnes
range. According to the BSEF, OctaBDE was commercialized sometime in the mid
70’s. By the early 2000’s global production was <4000 tonnes/year and by
the time production ceased, demand was <500 tonnes. While Thus, assuming
30 years of production at 6000 tonnes per year gives 180,000 tonnes, a figure
within the proposed range.
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Fate
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The persistence of these PBDE in the environment is well
documented.
Bioaccumulation potential is confirmed at least for some isomers,
as well as biomagnification in some food chains. As debromination into other
POP-like chemicals is expected to be a relevant contribution to the
dissipation of hexa to nonaBDE, the absence of food-chain biomagnification
for a specific congener on a specific taxonomic group does not necessarily
decrease the overall concern. The data available for lower and higher
brominated congeners (some of them also present in c-octaBDE) show that they
have potential for long-range environmental transport.
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Effects
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Unfortunately, the available information on the toxicity and
ecotoxicity of hexa to nonaBDE [which make up commercial OctaBDE] is very
limited. Effects on mammals and birds include slight fetotoxicity, increased
liver weights, and delayed skeletal ossification. Other observed effects
include immunotoxicity and neurotoxicity. There is an increasing evidence
suggesting similar toxicological profiles and therefore, equivalent hazards
and concerns, between PBDEs and PCBs. The potential for formation of
polybrominated dibenzo-p-dioxins and
furans (See European Communities, 2003 for a general discussion),
although not considered in this risk profile, should also be taken into
account.
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Exposure
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Exposure to components of c-OctaBDE in remote areas is confirmed
and based on the available information should be attributed to a combination
of releases and transport of c-OctaBDE, c-pentaBDE (for hexaBDE) and
c-DecaBDE (for nonaBDE), and to the debromination of DecaBDE in the
environment and biota. Despite its large molecular size, the evidence
demonstrates the capability of c-OctaBDE components to cross the cellular
membranes and to accumulate in biota. The exposure route is mainly via food.
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Status
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Octa-BDE takes part of the list of selected substances for the
OSPAR lists (no 236). Under the reviewed list, Octa-BDE is put under section
C – about the substances put on hold because they are not produced and/or
used in the OSPAR catchment or are used in sufficiently contained systems
making a threat to the marine environment unlikely. C- OctaBDE is being
considered under UNECE Convention on Long range Transboundary Air Pollution
(LRTAP) and its Protocol on Persistent Organic Pollutants (POPs)
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Alternatives
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Will be discussed in Annex F evaluation
if OctaBDE advances.
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PentaBDE
Draft Risk Management Evaluation May 2007
http://www.pops.int/documents/meetings/poprc/drprofile/drme/DraftRME_PeBDE.pdf
Risk Profile UNEP/POPS/POPRC.2/17/Add1
http://www.pops.int/documents/meetings/poprc_2/meeting_docs/report/POPRC-2%20rep%20add1.pdf
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Composition
|
Commercial pentabromodiphenyl ether
(C-PentaBDE) refers to mixtures of bromodiphenyl ether congeners in which the
main components are 2,2', 4,4'- tetrabromodiphenyl ether (BDE-47 CAS No.
40088-47-9) and 2,2',4,4',5-pentabromodiphenyl ether (BDE-99 CAS No.
32534-81-9), which have the
highest concentration by weight with respect to the other components of the
mixture.
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Uses
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Commercial pentabromodiphenyl ether mixtures (C-PentaBDE) are used for flame retardant purposes as
additives in consumer products. The commercial mixtures contain brominated diphenyl ether
congeners with three to seven bromines in the molecule, but molecules with
four and five bromines predominate. The proportion of the different
polybromodiphenyl ether (PBDE) congeners in C-PentaBDE varies in different
regions of the world. The main source in North America and Western
Europe has been the C-PentaBDE incorporated in polyurethane
foam, used in domestic and public furniture. This use is now mainly phased
out. The information is too limited to draw conclusions on the importance of
other uses, like textiles, electrical and electronic products, building
materials, vehicles, trains and aeroplanes, packaging, drilling oil fluid and
rubber products. While some representative examples are covered, detailed
information on use is lacking for many regions of the world. Emission sources
include production filter waste, foam production, release from products,
wastes, landfills, incineration, and waste recycling.
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Fate
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Due to its high persistency in air, the main
route for long-range transport of PentaBDE - as with so many substances that
are sufficiently volatile, persistent and bioaccumulative - is through the
atmosphere. Modelling and
environmental studies indicate that the transport is through a series of
deposition/volatilization hops towards the poles but particulate transport is
known to be important, too. Long-range transport through water and emigrating
animals is also likely. Several studies show that PentaBDE in soil and
sediments is bioavailable, enters the food chain and that it bioaccumulates
and biomagnifies in the food webs, ending up in high levels in top predators.
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Effects
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Toxicological studies have demonstrated
reproductive toxicity, neurodevelopmental toxicity and effects on thyroid
hormones in aquatic organisms and in mammals. The potential for the toxic
effects in wildlife, including mammals, is evident. A Canadian assessment of
risk quotients suggests that the highest risks accrue to species high in the
food chain. Information is lacking on the effects in humans of short-term and
long-term exposure, although it is to be expected that vulnerable groups can
be pregnant women, embryos and infants.
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Exposure
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PentaBDE is widespread in the global
environment. Levels of components of
C-PentaBDE have been found in humans in all UN regions. Most trend analyses
show a rapid increase in concentrations of PentaBDE in the environment and in
humans from the early 1970s to the middle or end of the 1990s, reaching plateau levels in some regions in the late 1990s, but
continuing to increase in others. The levels in North America and
the Arctic are still rising. Vulnerable ecosystems and species are
affected, among them several endangered species. Some individuals of
endangered species show levels high enough to be of concern. Potential
exposure to humans is through food, and through use of products and contact
with indoor air and dust. PentaBDE transfers from mothers to embryos and
lactating infants. Considerably higher levels are found in humans from North America in general. About 5% of general populations have been
found to be subjected to elevated exposure.
This, together with the estimates of the long half-life of PentaBDE
congeners in humans, raises concern for long-term effects on human health.
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Status
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An OSPAR Commission background document on
PBDEs was reviewed by Sweden
in 2001. The next full review of this document is not planned before 2008. At
the 4th North Sea Conference, it was decided to phase out the use of
brominated flame retardants by 2020. C-PentaBDE was nominated as a new POP to
the UNECE Convention on Long-range Transboundary Air Pollution in 2004 by Norway. In
December 2005 it was considered by the Executive Body of the Convention to
meet the screening criteria for POPs, set out in EB decision 1998/2. They
requested that the UNECE Task Force on POPs continue with the review and further
explore management strategies. The EU notified PentaBDE to the Rotterdam
Convention in 2003. For it to become a candidate, bans of the substance must
be notified by two parties under the Convention.
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Alternatives
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There are three ways to provide flame retardancy in products
without using BFRs: 1) substitute them with another flame retardant in a
given material (i.e. plastic or foam); 2) substitute them with another flame
retardant in a different type of plastic or foam; or 3) redesign the product
so that there is no need for using flame retardants. Some manufacturers have
already replaced C-PeBDE with cost competitive non-POPs alternatives in all
uses, including flexible polyurethane and electronics.
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PeCB
Draft Risk Profile May 2007
http://www.pops.int/documents/meetings/poprc/drprofile/drp/DraftRiskProfile_PeCB.pdf
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Composition
|
Pentachlorobenzene belongs to the group of chlorobenzenes, which
are characterized by a benzene ring in which the hydrogen atoms are
substituted by one or more chlorines.
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Uses
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No current intentional use believed though PeCB was a component of
a chlorobenzenes mixture used to reduce the viscosity of PCB products
employed for heat transfer. Formerly, PeCB and TeCB could be found in
dyestuff carriers. PeCB can be found as an impurity in several herbicides,
pesticides and fungicides currently in use in Canada (Environment Canada,
2005). Pentachlorobenzene was identified in pentachloronitrobenzene (quintozene),
endosulfan, chlorpyrifos-methyl, atrazine, and clopyrilid, but not in
simazine, chlorothalonil, picloram and dacthal (US EPA, 1998). Technical
grade hexachlorobenzene (HCB) contains about 98 % HCB, 1.8 %
pentachlorobenzene and 0.2 % 1,2,4,5-tetrachlorobenzene (WHO-IPCS, 1997). The
available data suggest a decrease in pentachlorobenzene use for the
preparation of quintozene. However, this conclusion is based on data for
Europe and North America only. PeCB may have
been used in the past as a fungicide and as a flame retardant (Van de
Plassche et al., 2002).
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Releases
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Currently, PeCB is believed to come
primarily from unintentional production from sources that include: PCBs,
chlorinated solvents, pesticides, chemical manufacturing, aluminum casting,
waste combustion including barrel burning, ore treatment for metal production
of magnesium, copper, niobium, tantalum, titanium dioxide production, wood
treatment plants, and hazardous waste incineration.
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Fate
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PeCB is spread widely in the environment on a global scale. Levels
of PeCB in abiotic and biotic media in remote regions such as the (ant)
arctic environment are available, as well as monitoring data on PeCB in
abiotic and biotic media of temperate zones. Pentachlorobenzene has a high
bioaccumulation potential. Due to the fact that biotransformation of PeCB
will be insignificant and the substance is very hydrophobic, the compound may
also have a high biomagnification potential.
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Effects
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PeCB is moderately toxic to humans. Animal studies reveal effects
including decreased thyroxin, abnormal sperm, and histopathological effects
on the kidneys. Pentachlorobenzene is very toxic to aquatic organisms and may
cause long-term adverse effects in the aquatic environment.
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Exposure
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PeCB has been detected in breast milk and found to accumulate in
human placenta (Shen et al., 2007). PeCB has also been measured in abdominal,
mammary, and perirenal fat tissue from 27 adult Finnish males and females
(Smeds and Saukko, 2001). Workers with occupational exposure to PeCB were
found to have higher levels of the substance in blood than control groups
(Lunde and Bjorseth, 1977). PeCB has been found in Alaskan grayling, lake
trout, cod, and halibut and in Greenland
krill, cod, and arctic char. It is also found in seals from northern Russia, Canada,
and Greenland and in whale blubber from Canada
and musk ox blubber from Greenland. PeCB is
found in polar bears from the arctic Svalbard islands, Alaska,
Canada, and East Greenland. PeCB is present in arctic fox and Canadian
snow crabs.
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Status
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The European Commission has submitted a proposal to include
pentachlorobenzene to the Protocol to the 1979 Convention on Long Range
Transboundary Air Pollution (LRTAP) on Persistent Organic Pollutants to the
Executive Secretariat of the United Nations Economic Commission for Europe in 2006. PeCB is identified as a priority
substance within the European Water Framework Directive (2000/60/EC). Within
the list of these priority substances so-called priority hazardous substances
are identified which are of particular concern for the freshwater, coastal
and marine environment. These substances will be subject to cessation or
phasing out of discharges, emissions and losses within 20 years after
adoption of the Directive. The European Commission has proposed to include
pentachlorobenzene as a priority hazardous substance. [COM(2006) 397 final].
PeCB is listed on the OSPAR 1998 List of Candidate Substances (OSPAR, 1998).
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Alternatives
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Will be discussed in Annex F evaluation
if PeCB advances.
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PFOS
Draft Risk Management Evaluation May 2007
http://www.pops.int/documents/meetings/poprc/drprofile/drme/DraftRME_PFOS.pdf
Risk Profile UNEP/POPS/POPRC.2/17/Add5
http://www.pops.int/documents/meetings/poprc_2/meeting_docs/report/POPRC-2%20rep%20add5.pdf
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Composition
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PFOS is a fully fluorinated anion, which
is commonly used as a salt or incorporated into larger polymers. PFOS and its
closely related compounds, which contain PFOS impurities or substances which
can give rise to PFOS, are members of the large family of perfluoroalkyl
sulfonate substances. PFOS
can be formed by degradation from a large group of related substances,
referred to as PFOS-related substances
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Uses
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Uses
include: fire fighting foams, carpets, leather/apparel, textiles/upholstery,
paper and packaging, coatings and coating additives, industrial and household
cleaning products, pesticides and other insecticides, photographic industry,
photolithography and semiconductor manufacturing, hydraulic fluids, and metal
plating. PFOS-related substances have been used to provide soil, oil and
water resistance to textiles, apparels, home furnishings and upholstery,
carpets, and leather products. PFOS-related substances have been used in the
packaging and paper industries in both food packaging and commercial
applications to impart grease, oil and water resistance to paper, paperboard
and packaging substrates. 3M PFOS-based products were sold in the past to a
variety of formulators to improve the wetting of water-based products
marketed as alkaline cleaners, floor polishes (to improve wetting and
levelling), denture cleansers and shampoos. Several of these products
(alkaline cleaners, floor polishes, shampoos) were marketed to consumers;
some products were also sold to janitorial and commercial services. A number
of the alkaline cleaners were spray-applied.
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Releases
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PFOS
and PFOS-related substances can be released to the environment at their
manufacture, during their use in industrial and consumer applications and
from disposal of the chemicals or of products or articles containing them
after their use.
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Fate
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PFOS
is extremely persistent. It has not shown any degradation in tests of
hydrolysis, photolysis or biodegradation in any environmental condition
tested. The only known condition whereby PFOS is degraded is through high
temperature incineration. PFOS meets the criteria for the potential for
long-range transport. This is evident through monitoring data showing highly
elevated levels of PFOS in various parts of the northern hemisphere. It is
especially evident in the Arctic biota, far from anthropogenic sources. PFOS
also fulfils the specific criteria for atmospheric half-life.
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Effects
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PFOS has demonstrated toxicity towards mammals in
sub-chronic repeated dose studies at low concentrations, as well as rat
reproductive toxicity with mortality of pups occurring shortly after birth. Environmental
toxicity data for PFOS is predominantly found for aquatic organisms such as
fish, invertebrates and algae, and for birds. PFOS is toxic to aquatic
organisms with mysid shrimp and Chironomus
tentans being the most sensitive organisms.
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Exposure
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Most
notable and alarming are the high concentrations of PFOS that have been found
in Arctic animals, far from anthropogenic sources. PFOS has been detected in higher trophic
level biota and predators such as fish, piscivorous birds, mink, and Arctic
biota. Also, predator species, such as eagles, have been shown to accumulate
higher PFOS concentrations than birds from lower trophic levels. Even with
reductions in manufacturing of PFOS by some manufacturers, wildlife, such as
birds, can continue to be exposed to persistent and bioaccumulative
substances such as PFOS simply by virtue of its persistence and long-term
accumulation. Concentrations in Canadian Arctic polar bear are among the
highest in polar bears worldwide but the exposure concentrations are not
considered an anomaly given similar concentrations in polar bears in other
North America and European Arctic locations and high concentrations in other
wildlife globally as shown above.
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Status
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PFOS was added to the list of Chemicals for
Priority Action under OSPAR in June 2003. Persistent Organic Pollutants
Protocol to the Long-Range Transboundary Air Pollution Convention (“LRTAP”): The Executive Body of the UNECE
LRTAP Convention agreed that PFOS be considered a POP as defined under the
Protocol on POPs and requested that the UNECE Task Force on POPs continue
with the review of the substance and exploring management strategies.
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Alternatives
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The draft risk management evaluation
received responses from various industries which claimed that the following
uses have no technically feasible alternatives: photo imaging, photo mask,
semi-conductor, aviation hydraulic fluids, and manufacture of ant baits for
leaf-cutting ants. The industries also claim that the following uses have
alternatives but would have to be gradually phased in: metal plating and fire
fighting foam.
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SCCPs
Draft Risk Profile May 2007
http://www.pops.int/documents/meetings/poprc/drprofile/drp/DraftRiskProfile_SCCP.pdf
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Composition
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SCCPs cover carbon chain lengths of 10 – 13 with 1 – 13 chlorine atoms.
Production yields extremely complex mixtures, owing to the many possible
positions for the chlorine atoms, and standard analytical methods do not
permit their separation and identification. Thus the commercial mixture is
proposed for listing.
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Uses
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SCCPs are used primarily in metalworking applications. Other uses
include uses as flame retardants or plasticizers in PVC, paints, adhesives,
sealants in buildings, PCB substitutes in gaskets, leather fat liquors, and
flame retardants in rubber, car carpets, textiles, and other polymers. SCCPs
used as flame retardants are added to rubber in a proportion of 1–10%.
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Releases
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Anthropogenic
releases of CPs into the environment may occur during production, storage,
transportation, industrial and consumer usage of CP-containing products,
disposal and burning of waste, and land filling of products such as PVC,
textiles, painted materials, paint cans and cutting oils.
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Fate
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SCCPs
are not expected to degrade significantly by hydrolysis in water, and dated
sediment cores indicate that they persist in sediment longer than 1 year.
SCCPs have atmospheric half-lives ranging from 0.81 to 10.5 days, indicating
that they are also relatively persistent in air. SCCPs have been detected in
a diverse array of environmental samples (air, sediment, water, wastewater,
fish and marine mammals) and in remote areas such as the Arctic
(which is additional evidence of long range transport). Evidence for the
bioaccumulation of SCCPs is further supported by the high concentrations of
SCCPs measured in marine mammals and aquatic freshwater biota (e.g., beluga
whales, ringed seals and various fish).
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Effects
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SCCPs
can harm sensitive aquatic organisms at relatively low concentrations (i.e.
below threshold criteria
of 1 mg/L used to categorize substances on Canada’s Domestic Substances
List). SCCPs affect the liver, kidney and thyroid in rats including increased
liver, weight, altered liver enzymes, and enlarged thyroid. Rodent studies showed dose related
increases in adenomas and carcinomas in the liver, thyroid, and kidney. There
continues to be contention over the mechanisms of these tumors and whether
they are relevant for human health.
SCCPs were classified as a group 2B carcinogen (possibly
carcinogenic to humans) by the International Agency for Research on Cancer
(IARC). There are no data on fertility or developmental
effects for humans.
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Exposure
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SCCPs
have been found in breast milk from Inuit women in Northern Quebec in the UK. They
have been measured in cow’s milk and in butter from Denmark, Wales, Normandy, Bavaria, Ireland and southern and northern Italy.
SCCPs have been measured in seabird eggs, Arctic char, cod, blue mussel,
spart, redfish, herring, halibut, sardine, trout, dab, flounder, beluga
whale, walrus, ringed seal, reindeer, and osprey.
SCCPs were measured in air in
several countries including Canada,
the United Kingdom (U.K.) and Norway.
SCCPs were detected in all eight sewage treatment plant final effluents
sampled from southern Ontario,
Canada. Total
SCCPs (dissolved and particulate C10-13) ranged from 59 to 448
ng/L. The highest concentrations were
found in samples from treatment plants in industrialized areas, including
Hamilton, St. Catharine’s and Galt. SCCPs were detected in surface waters in Ontario and Manitoba, Canada. SCCPs
were detected in sediments around the Great Lakes in Canada, Germany,
Czech Republic
and the United Kingdom. They have also been detected in Arctic
sediment.
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Status
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In December 2006, the Parties to the UNECE POPs Protocol agreed
that SCCPs should be considered as a POP as defined under the Protocol, and
requested that the Task Force continue with the Track B reviews of the
substances and explore management strategies for them. In 1995, OSPAR
Commission for the Protection of Marine Environment of the North-East
Atlantic adopted a decision on SCCPs (Decision 95/1). This established
a ban on the use of SCCPs in all areas of application by the end of 1999 with
exemptions for use of SCCPs in dam sealants and underground conveyor belts until
2004. Similar to OSPAR, the Baltic Marine Environment Protection Commission
(HELCOM) has included SCCPs on their list of harmful substances. SCCPs
have been identified as priority hazardous substances in the field of water
policy under the Water Framework Directive (Directive 2000/60/EC of 23
October 2000) and are listed in the draft amendment of Directive 2000/60/EC,
which defines water quality standards for European surface waters. Substances
listed in this Directive will be subject to cessation or phasing out of
discharges, emissions and losses with in an appropriate time table that shall
not exceed 20 years (EC, 2005). The most important uses (metal working fluids
and leather fat liquors) in the EU were restricted in directive 2002/45/EC.
SCCP in plastics is a major use in Europe
that was not covered by directive 2002/45/EC.
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Alternatives
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Will be discussed in Annex F evaluation
if SCCPs advance.
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[5] Rotterdam
Convention http://www.pic.int.
[6] OSPAR Convention for the Protection of the
Marine Environment of the Northeast Atlantic.
http://www.ospar.org/
[8] European Union Water Framework Directive
http://ec.europa.eu/environment/water/water-framework/index_en.html
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