Chlordane carcinogenicity

All use of chlordane was banned in Norway in 1967 (Ingebrigtsen et al. 1984). In August 1975, the USEPA issued its intent to suspend registrations and prohibit production of all pesticides containing heptachlor or chlordane, based on evidence of carcinogenicity (Glooschenko and Lott 1977). On July 1, 1983, chlordane use was prohibited in the United States for any purpose except to control underground termites. A similar situation exists in Japan (Ohno et al. 1986 Tojo et al. 1986). 

Technical chlordane is an organochlorine compound first introduced into the United States in 1947 in a variety of formulations for use as a broad-spectrum pesticide. By 1974, about 9.5 million kg of chlordane were being produced annually. Concern over the potential carcinogenicity of chlordane has led to sharply curtailed production. Since 1983, chlordane use in the United States has been prohibited, except for control of underground termites. 

Many species of aquatic organisms are adversely affected at concentrations in water between 0.2 and 3.0 pg/L technical chlordane. Sensitive bird species had reduced survival on diets containing 1.5 mg chlordane per kilogram ration, or after a single oral dose as low as 14.1 mg chlordane per kilogram body weight. Chlordane has produced liver cancer in laboratory strains of domestic mice, but carcinogenicity has not been established in other mammals. 

Epstein, S.S. 1976. Carcinogenicity of heptachlor and chlordane. Sci. Total Environ. 6 103-154. 

International Agency for Research in Cancer (IARC). 1979. Chlordane. Int. Agen. Res. Cancer, Monographs. Eval. Carcinogen. Risk Chem. Hum. 20 45-65. 

Toxicology. Chlordane is a convulsant it is carcinogenic in experimental animals. 

Chlordane was not mutagenic to bacteria/ The 2003 ACGIH threshold limit valuetime-weighted average (TLV-TWA) for chlordane is 0.5mg/m with a notation for skin absorption and an A3-confirmed animal carcinogen with unknown relevance to humans designation. 

National Cancer Institute Bioassay of Chlordane for Possible Carcinogenicity, Technical Report Series No 8. DHEW (NIH) Pub No 77-808. Washington, DC, US Government Printing Office, 1977... 

One excess cancer per million (10 ) is associated with lifetime exposure to chlordane in drinking water at concentrations as low as 0.027 pg/L, the most conservative estimate. A lifetime health advisory computation was not possible because chlordane is a probable human carcinogen (USEPA 1988). 

Chlordane is reported to increase the incidence of hepatocarcinoma in rodents (ref. 117a). Both chlordane and heptachlor are classified as animal positive carcinogens by the 1ARC (ref. 117h). 

The production of chlordane was reduced from. 3.5 to 4.0 million pounds in 1986 to 100,000 to 1 million pounds in 1991 (ATSDR, 1994a). More than 63 million kg of chlordane were produced and used in the United States, mostly after 1960 before sales and its use were suspended in 1988 (Dearth Hites, 1991a,b). Restrictions were imposed on the use of chlordane in 1979 because of its potential human carcinogenicity. After this time chlordane was used mainly for underground termite control and in building construction (Dearth Hites, 1991a,b). In Japan, chlordane was only permitted for the control of termites and powder post beetles (Miyazaki et al., 1980). USEPA cancelled its registration for commercial... 

Chlordane Generalized convulsions, reproductive toxicity, birth defects, loss of consciousness, change in EEG pattern, hepatic disorders, neurologic disturbances, mutagenicity, carcinogenicity... 

Environmental Protection Agency, Carcinogenicity Assessment of Chlordane and Heptachlor Epoxide. EPA/600-/6-87/004. Carcinogen Assessment Group, Office of Health and Environmental Assessment, Washington, DC, 1986. 

Chlordane is a wide-spectrum insecticide, and it is being phased out of use. It is classified as a probable human carcinogen (EPA Group B2). 

SAFETY PROFILE Confirmed carcinogen with experimental carcinogenic data. A poison by ingestion, skin contact, intraperitoneal, and intravenous routes. Human mutation data reported. Acute exposure and chronic doses have caused liver damage. See also closely related chlordane. In humans, a dose of 1-3 g can cause serious symptoms, especially where liver impairment is the case. Acute symptoms include tremors, convulsions, kidney damage, respirator)" collapse, and death. When heated to decomposition it emits toxic fumes of Cl . 

Chronically, symptoms include anemia, leukopenia, thrombocytopenia, jaundice, and abnormal blood serum chemistry results. Reproductive or teratogenic effects do not appear to be present. Mutagenicity testing generally indicates that chlordane is not mutagenic. Chlordane is classified as group 2B (possibly carcinogenic to humans) by the lARC. 

See also Carcinogen Classification Schemes Charcoal Chlordane Diazepam LD50/LC50 (Lethal Dosage 50/ Lethal Concentration 50) Organochlorine Insecticides. 

In spite of the fact that in warm-blooded organisms chlordane and heptachlor are substantially converted to hydrophylic metabolites and are excreted in this form, accumulation in the fatty tissues is considerable. In the USA the presence of these compounds was established in 73% of the milk product investigated and in 77% of the meat and fish samples. At the same time, animal experiments showed that their carcinogenicity is probable. Therefore, the Environmental Protection Agency recommended a complete ban on the use of these insecticides in the USA. 

The oncogenicity concerns with chlordane persisted until Velsicol and EPA negotiated a voluntary cancellation of most of the termiticide uses in 1987 and avoided a cancellation hearing. The cancellation hearing was expected to be hard fought, as the evidence of carcinogenicity was based on mouse liver tumors, which provided evidence of a very different weight in 1987 than in 1979. 

It is well established that organochlorine pesticides, such as DDT, dleldrin, aldrin, heptachlor and chlordane, can cause tumors in rodents, particularly liver cancer in mice. A number of investigations have sought to determine whether these pesticides are carcinogenic to humans. 

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