Metabolites of 2,4',5-trichlorobiphenyl in rats

Nineteen metabolites of 2,4',5-trichlorobiphenyl were isolated from rat urine, faeces and bile. These metabolites resulted from one or more of the following transformations: dechlorination, hydroxylation, thiolation, methylthiolation, methylthio oxidation, dihydrodiol formation, mercapturic acid formation and conjugation with glucuronic acid. Mercapturic acid-pathway metabolites were the major metabolites in the bile. Methylthio-, methylsulphinyl- and methylsulphonyl-containing metabolites were the major metabolites in the faeces of control rats. A synthetic pathway for the preparation of sulphur-containing metabolites of trichlorobiphenyl is described.