Trans-chlordane

Figure 13.1 Chemical structure of chlordane-related compounds 1, chlordene (4,5,6,7,8,8-hexachloro-3a,4,7,7a-tetrahydro-4, 7-methanoindene) 2, c/ s-chlordane, also known as alpha-chlordane (1-exo, 2-exo, 4,5,6,7,8,8-octachloro-2,3,3a,4,7,7a-hexahydro-4,7-methanoindene) 3, trans-chlordane, also known as gamma-chlordane (1-exo, 2-endo, 4,5,6,7,8,8-octachloro-2,3,3a,4,7,7a-hexahydro-4,7-methanoindene) 4, heptachlor (1,4,5,6,7,8,8-heptachloro-3a,4,7,7a-tetrahydro-4,7-methanoindene) — technical heptachlor contains about 15% c/s-chlordane and 2.5% trans-chlordane 5, heptachlor epoxide (1,4,5,6,7,8,8-heptachloro-2,3-epoxy-3a,4,7,7a-tetrahydro-4,7-methanoindene) and 6, oxychlordane, also known as octachlor epoxide (1-exo, 2-endo, 4,5,6,7,8,8-octachloro,2,3-exo-epoxy-2,3,3a,4,7,7a-hexahydro-4,7-methanoindene). 

Excretion kinetics of chlordane are complex, and different isomers exit through different pathways (USEPA 1980, 1988). In rats, chlordane elimination was almost complete 7 days after receiving single oral doses up to 1 mg/kg body weight (BW) 24 hours after treatment, 70% of the r/. v-chlordane and 60% of the trans-chlordane had been excreted (WHO 1984). In rodents, chlordane and its metabolites were usually excreted in feces, regardless of the administration route the cis-isomer was excreted slightly faster than the trans-isomer, although identical metabolites seemed to be formed (Menzie 1969, 1980 USEPA 1980 WHO 1984 Nomeir and Hajjar 1987). In rabbits, however, up to 47% of the administered dose was voided in the urine, and cis- and /ran.v-chlordanc were excreted at the same rate (Nomeir and Hajjar 1987). 

Microorganisms such as Nocardiopsis sp., an actinomycete, can metabolize cis- and trans-chlo-rdane to at least eight solvent-soluble substances, including dichlorochlordene, oxychlordane, hep-tachlor, heptachlor endo-epoxide, chlordene chlorohydrin, and 3-hydroxy-trans-chlordane (Beeman and Matsumura 1981). Based on studies of chlordane metabolism in animals, four metabolic pathways are proposed (Feroz and Khan 1979a WHO 1984 Nomeir and Hajjar 1987 USEPA 1988) ... 

Although technical chlordane is a mixture of compounds, two metabolites — heptachlor epoxide and oxychlordane — can kill birds when administered through the diet (Blus et al. 1983). These two metabolites originate from biological and physical breakdown of chlordanes in the environment, or from metabolism after ingestion. Heptachlor can result from breakdown of cis- and trans-chlordane, eventually oxidizing to heptachlor epoxide oxychlordane can result from the breakdown of heptachlor, m-chlordane, tra .s-chlordane, or fram-nonachlor (Blus et al. 1983). Heptachlor epoxide has been identified in soil, crops, and aquatic biota, but its presence is usually associated with the use of heptachlor, not technical chlordane — which also contains some heptachlor (NRCC 1975). Various components in technical chlordane may inhibit the formation of heptachlor epoxide or accelerate the decomposition of the epoxide, but the actual mechanisms are unclear (NRCC 1975). 

Chlordane has been detected in both groundwater and surface water at low levels of 0.001 to 0.01 pg/L (USEPA 1988). A high frequency of chlordane detection was noted in seawater samples collected from a Hawaiian marina up to 90% of all samples contained cw-chlordane, and 68% contained trans-chlordane (IARC 1979). Because of chlordane s use as a soil-injected insecticide and its persistence, it has the potential to contaminate groundwater, particularly when it is applied near existing wells (USEPA 1988). 

BIRDS, 4 species, fed diets containing 71% c/ s-chlordane and 23% trans-chlordane at 50-500 mg/kg diet... 

Mortality reached 50% on day 40 maximum residues in brains of birds dying during exposure (or sacrificed), in mg/kg FW, were 6.5 (9.0) for c/s-chlordane, 4.5 (9.0) for trans-nonachlor, 3.2 (9.0) for trans-chlordane, and 1.0 (2.0) for c/ s-nonachlor (Dr. O.H. Pattee, Patuxent Wildlife Research Center, personal communication)... 

MONKEY, Macaca fascicularis 1 or 10 mg/kg BW of trans-chlordane given once weekly for 5 weeks by subcutaneous injection. Adipose tissue, blood, and skin lipids analyzed for up to 20 weeks after the last injection trans-Chlordane and oxychlordane were detected in all tissues. In blood and adipose tissue, trans-chlordane decreased rapidly and oxychlordane increased gradually until a plateau was reached. Good correlations were determined for all chemicals between blood and adipose tissue, regardless of collection time and dose level, and between skin lipids and adipose tissue. At the high dose, trans-chlordane reached a maximum of 35 mg/kg FW in adipose tissue, but was not detectable after 20 weeks. The oxychlordane concentration in adipose tissue of the high-dose group was 25 mg/kg FW after the last injection, and 18 mg/kg FW after 20 weeks (Sasaki et al. 1992)... 

Fed diets containing 35 mg/kg trans-chlordane for 78 weeks Daily oral dose of 50 mg technical chlordane/kg BW for 15 days 83-392 mg/kg BW Fed diets containing 100 or 200 mg/kg ration of c/s-chlordane or trans-chlordane for 11-15 days... 

Maximum residues, in mg/kg lipid, in females fed 100 mg/kg c/s-chlordane were 23 for c/s-chlordane and 100 for oxychlordane for the 200 c/s-chlordane group, levels were 48 for c/s-chlordane and 182 for oxychlordane. Females fed 100 mg/kg trans-chlordane had 10 mg/kg lipid of trans-chlordane and 201 of oxychlordane for the 200 mg/kg group, residues were 23 mg/kg lipid of trans-chlordane and 470 of oxychlordane for all groups, residues in males were 6-21 times lower than in females (Nomeir and Hajjar 1987)... 

Technical chlordane consists of about 45 components, primarily m-chlordane (19%), trans-chlordane (24%), heptachlor (10%), cis- and iran.v-nonachlor (7%), and various chlordane isomers (22%). Chemical analysis of technical chlordane is difficult because of analytical interferences from other organochlorine compounds, nonstandardization of analytical techniques, variations in the number and relative composition of components in weathered chlordane, and uncertainty of the structural formulas and other properties of several compounds present. 

Beeman, R.W. and R. Matsumura. 1981. Metabolism of cis- and trans-chlordane by a soil microorganism. Jour. Agric. Food Chem. 29 84-89. 

Sasaki, K., Y. Kawasaki, K. Sekita, T. Ochai, M. Takeda, and M. Uchiyama. 1992. Disposition of beta-hexachlorocyclohexane, p, //-DDT, and trans-chlordane administered subcutaneously to monkeys (Macaca fascicularis). Arch. Environ. Contam. Toxicol. 22 25-29. 

Heptachlor is produced commercially by the free-radical chlorination of chlordene in benzene containing from 0.5% to 5.0% of fuller s earth. The reaction is run for up to 8 hours. The chlordene starting material is prepared by the Diels-Alder condensation of hexachlorocyclopentadiene with cyclopentadiene (Sittig 1980). Technical-grade heptachlor usually consists of 72% heptachlor and 28% impurities such as trans-chlordane, cis-chlordane, and nonachlor (HSDB 1990a). 

RCRA waste number U031, see 1-Butanol RCRA waste number U036, see Chlordane, crs-Chlordane, trans-Chlordane... 

Ivie, G.W., Knox, J.R., Khalifa, S., Yamamoto, I., and Casida, J.E. Novel photoproducts of heptachlor epoxide, trans-chlordane, and trans-nomddot. Bull Environ. Contam. Toxicol, 7(6) 376-383, 1972. 

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