The metabolism of 4-chlorobiphenyl in the pig.

1-Chlorobiphenyl was administered retrocarotidly in a saline oil emulsion to anesthetized pigs. The urine obtained from the pigs 2 h after injection of the 4-chlorobiphenyl was analyzed for metabolites. Mass spectrometric analysis indicated the presence of a monohydroxylated species (M+ 204) and a dihydroxylated compound (M+ 220) and these were identified as 4'-chloro-4-biphenylol and 4'-chloro-3,4-biphenyldiol, respectively. Examination of the urine extracts from pigs 0.5, 1, and 2 h after administration of the 4-chlorobiphenyl indicated an increase in both urinary metabolites with time, however, neither compound was detected in the bile. Blood and organ samples were examined also for metabolites and the results clearly showed the presence of 4'-chloro-4-biphenylol in the blood, kidney, and liver and absence in the lung, brain, and heart. The diol was not observed in any of these samples.