4-Chloro-, 2,4-dichloro-, 3,4-dichloro-, 2,3,5-trichloro-, and 2,4,5-trichlorophenylmercapturic acids were identified as main metabolites of lindane, γ-isomer of 1,2,3,4,5,6-hexachloro-cyclohexane, in rat urine. Pathways to these metabolites were shown to include ( 36 45)-hexachlorocyclohexene as the most important intermediary metabolite. ( 346 5)-Pentachlorocyclohexene and ( 346 5)-tetrachlorocyclohexene also seem to be involved in these pathways, while ( 36 45)-pentachlorocyclohexene plays a minor role in the pathway. Glutathione conjugation, using the rat liver soluble fraction, occurred directly on the polychlorocyclohexenes, not on their further transformed products. In in vivo biodegradation, ( 36 45)-hexachlorocyclohexene may be dechlorinated and dehydrochlorinated at the endoplasmic reticulum before it undergoes the glutathione conjugation in cytosol, although other polychlorocyclohexenes generally react in a manner similar to that in the in vitro reaction. © 1979.
