Pesticides kepone

Guzelian P. Fourteen Workers Exposed to the Pesticide Kepone are Probably Sterile, Research Reports // Occupat. Health and Safety Letters. 1976. Vol. 6. P.2. 

They also reported that on the basis of a review of data on over 2000 chemicals that have been tested in various in vitro and/or in vivo assays, all chemicals showing estrogenic properties contained a ring structure. All except five of the ring structures were aromatic (the exceptions being four steroids and the pesticide kepone). Table 18.1 illustrates the presence of these features in various categories of chemicals. 

D. S. Duvall and W. A. Rubey, "Laboratory Evaluation of High Temperature Destmction of Kepone and Related Pesticides," EPA-600/2-76-299, NTIS, Springfield, Va., Dec. 1976. 

For the last forty years, many reports have emerged on the hormone-like effects of chemical compounds such as pesticides and industrial chemicals upon wildlife and humans. The effects of these materials are believed to be either direct or indirect. Direct effects involve positive or negative interactions with the hormone receptors. Indirect effects may result when the synthesis of hormones or their receptors is altered, or the transport, metabolism, or elimination of hormones is modified in some way. The discovery of hormone-like properties of some compounds was made long after their release into the environment. It was shown soon after their introduction that aviation crop dusters handling DDT had low sperm counts and workers at a plant producing the insecticide kepone were reported to have low libido, sperm counts and to be impotent. Subsequently, experiments conducted in laboratory animals demonstrated unambiguously the oestrogenic activity of these pesticides. 9 refs. 

Gambrell et al. [223] have discussed the recovery of DDT, Kepone and Permethrin added to soil suspensions incubated under controlled redox potential and pH conditions to determine the effect of time on the levels of the insecticides and their degradation products. Samples were analysed by gas chromatography, pH and redox potential affected the persistence of pesticides to different degrees. The recovery of DDT was affected by redox potential but not by pH. 

Mirex and chlordecone are no longer made or used in the United States. Mirex and chlordecone were most commonly used in the 1960s and 1970s. Mirex was used as a pesticide to control fire ants mostly in the southeastern part of the United States. It was also used extensively as a flame retardant additive under the trade name Dechlorane in plastics, rubber, paint, paper, and electrical goods from 1959 to 1972 because it does burn easily. Chlordecone was used to control insects that attacked bananas, citrus trees with no fruits, tobacco, and ornamental shrubs. It was also used in household products such as ant and roach traps. Chlordecone is also known by its trade name Kepone . All registered products containing mirex and chlordecone were canceled in the United States between 1977 and 1978. 

Ebel RE. 1980. In vitro effects of chlordecone (Kepone) on hepatic microsomal cytochrome P-450. Pesticide Biochemistry and Physiology 14(3) 221-226. 

EPA. 1976. Kepone Position document 3. Arlington, VA U.S. Environmental Protection Agency, Special Pesticide Review Division. Document No. EPA/SPRD-80/62. 

EPA. 1990b. Kepone Position document 1. Washington, DC U.S. Environmental Protection Agency, Office of Pesticide Programs. Contract No. EPA-540-09-90-103... 

The pesticides included in this study were fenvalerate, chlordecone (kepone), chlorothalonil, and chlorpyrifos. Fenvalerate is a synthetic pyrethroid insecticide used, for example, for mites on chickens. Its chemical name is cyano(3-phenoxyphenyl)-methyl 4-chloro-alpha-(1-methylethyl)benzeneacetate. Chlordecone is an insecticide, no longer used, and has a chemical name decachloro-octahydro-l,3,4-metheno-2H-cyclobuta(cd)=pentalen-2-one. Chlorothalonil is fungicide used on tomatoes whose chemical name is 2,4,5,6-tetrachloroisophthalonitrile. Chlorpyrifos is an insecticide with a chemical name 0,0-diethyl 0-(3,5,6-trichloro-2-pyridyl)phosphorothioate. Chlorpyrifos is the U. S. Food and Drug Administration chromatographic reference standard since numerous specific detectors (electron capture, flame photometric in both sulfur and phosphorus modes, alkali flame, nitrogen phosphorus, and Hall detectors) are sensitive to it. 

That some chemicals persist for long periods has been recognized for many years. Most of the pesticidal chemicals that came into wide use in the 1930s and 1940s were chlorinated organic compounds such as DDT, dieldrin, chlordane, kepone, toxaphene, and several others. 

A two-step laboratory thermal-decomposition analytical system involving vaporization and thermal destruction was developed in 1975 by the University of Dayton Research Institute for EPA (6). Vaporization of pure pesticide occurred at 200 to 300°C and was followed by decomposition in a quartz tube at temperatures exceeding 900 C. The destruction efficiencies for DDT, Kepone, and mirex exceeded 99.99% at 2-s residence time and greater than 900 C. 

In microwave plasma destmction, organic material is channeled through a plasma detector tube where destruction is initiated by microwave radiation-producing electrons. The electrons react with the organic molecules to form free radicals and final simple reaction products such as SO2, CO2, CO, H2O, HPO3, COCI2, and Br2 [60]. In bench-scale tests, the plasma method resulted in extensive detoxification (>99% destmction) for several pesticides, including malathion, phenylmercuric acetate (PMA), and Kepone [55]. 

The state of Virginia closed a kepone pesticide plant because 70 of the 150 employees were suffering from kepone poisoning. The James River, which furnishes one fifth of all U.S. oysters, was contaminated. Kepone is made by dimerizing hexachlorocyclopentadiene and hydrolyzing to a ketone. Kepone is now banned. 

Kepone (decachloroctahydro-l,3.4-methano - 2H-cyclobuta [cd] pentalene-2-one) was patented in 1952 by Allied Chemical and registered for ant and cockroach control. Its chief use, however, was against the banana root borer in Central and South America, where the pesticide was obtained from Germanv (refs. 108a.b). ci... 

Evidence is similar for humans but limited, and includes male sterility, spontaneous abortions in human females, premature human fetuses, severe neurologic and CNS effects, blood dyscrasias, hepatotoxicity, accumulation of organohalogen pesticides in human lipid tissue—and, perhaps even more important, their presence in human breast milk, whence they can continue to exert influences on growth, development and hormonal, CNS and enzyme systems. Aldrin, dieldrin, chlordane, chlordecone (Kepone), heptachlor epoxide, hexachlorobenzene (HCB) and Mirex are all excreted via breast milk in the human female. This is also true for the related PCBs and PBBs that resist biodecomposition and maintain persistent residence in mammalian tissues. For them, excretion via breast milk may constitute the main—if not sole—elimination route. 

Mirex was first synthesized in 1946 but it was not introduced as a pesticide against hymenopterous insects, especially ants, until 1959 (Smith, 1991). Technical grade mirex consists of approximately 95% mirex and less than 2.5% chlordecone, mostly kepone (Eisler, 1985). Mirex is a stomach insecticide with little contact activity. The main use of mirex was against the imported fire ants in the south-eastern United States (WHO, 1984b). It has also been used to control leaf cutters in South America, harvester termites in South Africa, Western harvester ants in the United States, the pineapple mealy bug in Hawaii and it was proposed to have been used against yellow jacket wasps in the United States (WHO, 1995). Under the trade name of Dechlorane, mirex was used as a fire retardant in electronic components, fabrics, rubber, plastics and electrical goods (Eisler, 1985 WHO, 1995). 

Since well-established chemical derivatisation techniques already exist for the majority of the organochlorine insecticides (5, 1) it is not surprising that recent activity in this area has centred round compounds such as Kepone, Mirex, HCB, the PCBs, etc. which co-interfere in both the identification and quantitation of pesticide residues. 

Kepone and chlordane are synthesized from hexachlorocyclopentadiene and other five-membered-ring compounds. Show how these two pesticides are composed of two five-membered rings. 

Barthel E. 1981. Increased risk of lung cancer in pesticide exposed male agricultural workers. In American Society for Pharmacology and Experimental Therapeutics Symposium on Molecular Mechanism(s) of Toxicity of Chlordecone (Kepone), Rochester, MN, August 20, 1980. J Toxicol Environ Health 8 1027-1040. 

Alicyclic hydrocarbons are major components of petroleum (comprising from 20% to 67% of its volume) as well as components of plant oils and paraffins, microbial lipids, and pesticides. They range from simple molecules (e.g., cyclopentane and cyclohexane) to complex molecules (e.g., the pesticides aldrin and kepone shown in Figure 9.4). 

Over the last decades, large amounts of different man-made chemicals which can act as weak estrogens have been released into the terrestrial and aquatic environment and are distributed world-wide. Classical environmental estrogens are pesticides, such as o,p -DDT, and its metabohtes o,p -DDE and o,p -DDD, methoxychlor and its metabolites, chlordecone (Kepone ), dieldrin, Toxaphene, and endosulfan [126, 135, 136]. It is also known that many chemicals with very weak or no measurable estrogenic activity can be metabolized in organisms especially to hydroxylated compounds which may have much more estrogenic potency than the parent compound. Examples are methoxychlor and its mono- and di-demethylated derivatives [126,127] as well as the alkylphenol... 

Simultaneous exposure of rats to Aroclor 1254 or 1260 and chemicals of environmental concern such as the pesticides mirex, photomirex, and/or kepone in the diet resulted in increased severity of the liver lesions attributed to exposure to chlorinated biphenyls alone (Chu et al. 1980). Induction of hepatic AHH activity by Aroclor 1254 in the diet of lactating rats was increased in an additive manner by simultaneous dietary exposure to polybrominated biphenyls such as Firemaster BP-6 (McCormack et al. 1979). 

With respect to neurotoxins, there are a number of industrial chemicals (acrylamide, n-hexane, methyl n-butyl ketone, cresyl phosphate), pharmaceuticals (nitrofuradantoin, isoniazid), and pesticides (leptophos, Kepone ) which have been associated with neuropathic effects in humans (for reviews, see References 107,123, 124). Subchronic exposure studies in rodents and other animals such as cats have been used to identify and study the mechanism of action of neurotoxic chemicals which produce paralysis and behavioral changes in exposed animals. Studies are currently underway to evaluate the relative sensitivities of behavioral tests and morphological assays of peripheral and central nervous system axon morphology for detecting the earliest signs of chemically induced neuropathies. " ... 

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