Chlorinated mirex

Aspila et al. [338] reported the results of an interlaboratory quality control study in five laboratories on the electron capture gas chromatographic determination of ten chlorinated insecticides in standards and spiked and unspiked seawater samples (lindane, heptachlor, aldrin, 5-chlordane, a-chlordane, dield-rin, endrin, p, p -DDT, methoxychlor, and mirex). The methods of analyses used by these workers were not discussed, although it is mentioned that the methods were quite similar to those described in the water quality Branch Analytical Methods Manual [339]. Both hexane and benzene were used for the initial extraction of the water samples. 

Picer and Picer [357] investigated the recovery from fO litre samples of seawater of 0.1-1.0 xg/l chlorinated pesticides (DDT, DDE, TDE, and Dieldrin), and 1-2 xg/l PCB (Aroclor 1254). The recovery of Mirex during these steps varied between 80% and 90%. Losses of the investigated chlorinated hydrocarbons during these steps were 10-30% for about 10 ng pesticides. 

Mirex is a white, odorless, free-flowing, crystalline, nonflammable, polycyclic compound composed entirely of carbon and chlorine. The empirical formula is C10C112, and the molecular weight 545.54 (Hyde 1972 Waters et al. 1977 Bell et al. 1978 NAS 1978 Menzie 1978 Kaiser 1978). In the United States, the common chemical name is dodecachlorooctahydro-l,3,4-metheno-2H-cyclobuta[c,systematic name is dodecachloropentacyclo 5.3.0.02-6.03 9.04 8decane. Mirex was first prepared in 1946, patented in 1955 by Allied Chemical Company, and introduced... 

The significance of mirex residues in various tissues is unresolved, as is the exact mode of action of mirex and its metabolites. Minchew et al. (1980) and others indicated that mirex is a neurotoxic agent, with a mode of action similar to that of other chlorinated hydrocarbon insecticides, such as DDT. In studies with crayfish and radiolabeled mirex, mirex toxicosis was associated with neurotoxic effects that included hyperactivity, uncoordinated movements, loss of equilibrium, and... 

Terrence Collins is the Thomas Lord Professor of Chemistry at Carnegie Mellon University who contends that the dangers of chlorine chemistry are not adequately addressed by either academe or industry, and alternatives to chlorine and chlorine processors must be pursued. He notes, Many serious pollution episodes are attributable to chlorine products and processes. This information also belongs in chemistry courses to help avoid related mistakes. Examples include dioxin-contaminated 2,4,5-T, extensively used as a peacetime herbicide and as a component of the Vietnam War s agent orange chlorofluorocarbons (CFCs) polychlorinated biphenyls (PCBs the pesticides aldrin, chlordane, dieldrin, DDT, endrin, heptachlor, hexachlorobenzene, lindane, mirex, and toxaphene pentachlorophe-... 

Mirex and chlordecone are structurally similar insecticides. The only structural difference is that mirex has two bridgehead chlorine atoms where chlordecone has a carbonyl oxygen atom. As suggested by this similarity in structure, these two chemicals produce similar toxicities in a number of organs. Flowever, several aspects of the toxicity of mirex are distinctly different from those of chlordecone, and vice versa. Because the toxicity profiles of mirex and chlordecone differ significantly, each chemical will be discussed separately below. 

Although mirex and chlordecone are structurally very similar (differing only in the replacement of two bridgehead chlorine atoms on the mirex molecule with a carbonyl oxygen on the chlordecone molecule), significant differences exist in the toxicity profiles of these two chemicals. Therefore, mirex and chlordecone will be discussed separately below. 

The degradation of mirex in water occurs primarily by photolysis. During the photodecomposition of mirex, the chlorine atoms are replaced by hydrogen atoms. The primary photoreduction product of... 

Moser GJ, Meyer SA, Smart RC. 1992. The chlorinated pesticide mirex is a novel nonphorbol ester-type tumor promoter in mouse skin. Cancer Res 52(3) 631-636. 

Savage EP, Keefe TJ, Tessari JD, et al. 1981. National study of chlorinated hydrocarbon insecticide residues in human milk, USA I. Geographic distribution of dieldrin, heptachlor, heptachlor epoxide, chlordane, oxychlordane, and mirex. Am J Epidemiol 113(4) 413-422. 

Schoeny RS, Smith CC, Loper JC. 1979. Non-mutagenicity for Salmonella of the chlorinated hydrocarbons aroclor 1254, 1,2,4-trichlorobenzene, mirex and Kepone. Mutat Res 68(2) 125-132. 

Source Hexachlorobenzene may enter the environment from incomplete combustion of chlorinated compounds including mirex, kepone, chlorobenzenes, pentachlorophenol, PVC, polychlorinated biphenyls, and chlorinated solvents (Ahling et al., 1978 Dellinger et al., 1991). In addition, hexachlorobenzene may enter the environment as a reaction by-product in the production of carbon tetrachloride, dichloroethylene, hexachlorobutadiene, trichloroethylene, tetrachloro-ethylene, pentachloronitrobenzene, and vinyl chloride monomer (quoted, Verschueren, 1983). 

Using these systems, the thermal decomposition of DDE, DDT, diazinon, endrin, hexachlorobenzene, Kepone, mirex, and penta-chloronitrobenzene was studied, and in several instances stable intermediate products of incomplete destruction were observed. Kepone at 400 to 500°C yielded hexachlorocyclopentadiene, hexachlorobenzene, and an unidentified chlorinated hydrocarbon, all... 

Chlorinated hydrocarbons (1) Chemical substances containing only chlorine, carbon, and hydrogen. These include a class of persistent, broad-spectrum insecticides that linger in the environment and accumulate in the food chain. Among them are DDT, aldrin, dieldrin, heptachlor, chlordane, lindane, endrin, Mirex, hexachloride, and toxaphene. Other examples include TCE, which is used as an industrial solvent. (2) Any chlorinated organic compounds, including chlorinated solvents such as dichloromethane, trichloromethylene, and chloroform... 

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