Chlordecone is a synthetic organochlorine compound which has mainly been used as an agricultural insecticide. Chlordecone has been identified as a Persistent Organic Pollutant (POP) chemical under the Protocol to the Convention on Long-range Transboundary Air Pollution (CLRTAP) on Persistent Organic Pollutants and the provisions of the Protocol oblige Parties to phase out all production and uses of chlordecone. Chlordecone is chemically very similar to mirex, another pesticide which is already listed in the Stockholm Convention. This dossier focuses solely on the information required under paragraphs 1 and 2 of Annex D of the Stockholm Convention and it is mainly based on information from the following review reports: - Environmental Health Criteria (EHC) 43: Chlordecone. IPCS International Programme on Chemical Safety. United Nations Environment Programme. International Labour Organisation. World Health Organization. Geneva 1990 (available at: http://www.inchem.org/documents/ehc/ehc/ehc43.htm)
- Toxicological profile for mirex and chlordecone. U.S. Department of Health and Human Services. August 1995 (available at:http://www.atsdr.cdc.gov/toxprofiles/tp66-p.pdf).
These extensive review reports also serve as a source of further information referred to in paragraph 3 of Annex D of the Stockholm Convention on this candidate POP chemical. 1 Identification of the chemical 1.1 Names and registry numbers CAS chemical name: 1,1a,3,3a,4,5,5,5a,5b,6-decachloro-octahydro-1,3,4-metheno- 2H-cyclobuta[cd]pentalen-2-one Synonyms: decachloro-pentacyclo[5,2,1,02,6,03, 9,O5,8]decan-4-one, decachloro-octahydro-1,3,4-metheno-2H,5H- cyclobuta[cd]pentalen-2-one Trade names: GC 1189, Kepone, Merex CAS registry number: 143-50-0 EC number: 606-019-00-6 Structure (Structural Formula source: www.webbook.nist.gov ) Molecular formula: C10Cl10O Relative molecular mass: 490.6 2 Persistence Chlordecone is highly persistent in the environment. According to the information given in the review reports, the estimated half-life of chlordecone in soil is between 1-2 years. It is not expected to hydrolyze or biodegrade in the environment. Direct photodegradation is not significant. The primary process for the degradation of chlordecone in soil or sediments is anaerobic biodegradation. 3 Bioaccumulation Based on the lipophilic nature of this compound (high octanol-water partition coefficient), chlordecone has a tendency to both bioaccumulate and biomagnify in aquatic food chains. BCF values of over 60,000 have been measured in Atlantic silversides, an estuarine fish species. log KOW: 4.50 - 6.00 BCF:> 60 000 (Atlantic silversides) > 9 000 (Oysters) 16 600 (Fathead minnow) 4 Potential for long-range environmental transport Vapour pressure of chlordecone is less than 3*10 -5 mm Hg at 25°C. Chlordecone is not expected to be subject to direct photodegradation in the atmosphere. Its estimated half-life time in air is up to 50 years. Atmospheric transport of chlordecone particles was reported in USA during production years. Adverse effects Chlordecone is moderately toxic to laboratory mammals with single exposures. Acute toxic symptoms in all species tested included severe tremors. It can cause skin irritation. In long-termstudies, lower doses caused tremors and other neurological symptoms and liver hypertrophy. Chlordecone interferes with reproduction, and it is fetotoxic in experimental animals. It is not generally active in short-term tests for genetic activity. Chlordecone is carcinogenic in both sexes of mice and rats producing hepatocellular carcinomas. International Agency for Research on Cancer (IARC) concludes that there is sufficient evidence that chlordecone is carcinogenic in mice and rats. In the absence of adequate data in humans, it is reasonable to regard chlordecone as if it presented a carcinogenic risk to humans. The substance is very toxic to aquatic organisms. The few data available on terrestrial ecosystems indicate low acute toxicity but some long-term effects on vertebrate reproduction. 6 Statement of the reasons for concern Chlordecone is chemically very similar to mirex, an organochlorine pesticide already listed in the Stockholm Convention. According to the available data, chlordecone is very persistent in the environment. It has a great potential for bioaccumulation and in addition there is monitoring evidence of its biomagnification. Due to its physical and chemical properties and considerably long atmospheric half-life and based on findings in environmental samples, it can be assumed that chlordecone can be transported long distances in air, far from its sources. Chlordecone is associated with wide range of harmful effects to both mammals and aquatic organisms. Production and use of chlordecone has been ceased over the last decades in developed countries but it is assumed still to be produced or used as an agricultural pesticide in some developing countries. As chlordecone can move in the atmosphere far from its sources, single countries or groups of countries alone cannot abate the pollution caused by it. Regional action has already been considered necessary and chlordecone is totally banned under the CLRTAP Protocol on POPs. Due to the harmful POP properties and risks related to its possible continuing production and use, global action is warranted to eliminate this pollution. __ How can chlordecone affect my health? We do not know how mirex affects the health of people. Workers who were exposed to high levels of chlordecone over a long period (more than one year) showed harmful effects on the nervous system, skin, liver, and male reproductive system. These workers were probably exposed mainly through touching chlordecone, although they may have inhaled or ingested some as well. Animal studies with chlordecone have shown effects similar to those seen in people, as well as harmful kidney effects, developmental effects, and effects on the ability of females to reproduce. We do not know if these last three effects also occur in people. Animal studies have shown that ingesting high levels of mirex can harm the stomach, intestine, liver, kidneys, eyes, thyroid, and nervous and reproductive systems. How likely are chlordecone to cause cancer? The Department of Health and Human Services (DHHS) has determined that chlordecone may reasonably be anticipated to be carcinogens.There are no studies available on whether chlordecone are carcinogenic in people. However, studies in mice and rats have shown that ingesting chlordecone can cause liver, adrenal gland, and kidney tumors. Is there a medical test to show whether I've been exposed to chlordecone? Tests are available that measure the amount of mirex in blood, feces, fat, or milk, and the amount of chlordecone in blood, saliva, feces, or bile. However, these tests may require special equipment and they may not be available at your doctor's office. Has the federal government made recommendations to protect human health? The EPA has set a limit of 1 part of mirex per trillion parts of surface water (1 ppt) to protect fish and other aquatic life from harmful effects. The EPA suggests that ingesting an amount of mirex equal to 200 picograms (pg) per kilogram (kg) of your body weight per day is not likely to cause significant harmful health effects. The Food and Drug Administration (FDA) suggests that eating fish and other foods with concentrations below 100 ppt of mirex, or concentrations of chlordecone below 400 ppt, will not cause harmful health effects in people. The EPA requires that discharges or spills into the environment of 1 pound or more of chlordecone be reported. The National Institute for Occupational Safety and Health (NIOSH) recommends that average workplace air levels not exceed 1 microgram per cubic meter (1 m/gm3) of chlordecone over a 10-hour period. Some related Glossary Carcinogen: A substance that can cause cancer. CAS: Chemical Abstracts Service. Ingesting: Taking food or drink into your body. Insecticide: A substance that kills insects. Kilogram (kg): One thousand grams. Microgram (mg): One millionth of a gram. Picogram (pg): One trillionth of a gram. Sediment: Mud and debris that have settled to the bottom of a body of water.______________
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