Identification of metabolites of benzo[j]fluoranthene formed in vitro in rat liver homogenate.

The metabolites of benzo[j]fluoranthene (BjF) as formed in vitro using the 9000 X g supernatant from Aroclor-pretreated rats have been identified. Two dihydrodiols, trans-4,5-dihydro-4,5-dihydroxyBjF and trans-9,10-dihydro-9,10-dihydroxyBjF have been identified as major metabolites by comparison of their spectral and chromatographic properties with those of pure synthetic standards. There was no evidence that any of the isomeric 2,3-dihydrodiol was formed as a metabolite of BjF under these incubation conditions. Neither of the metabolic dihydrodiols of BjF were formed with a high degree of stereoselectivity. The enantiomeric purity of the 4,5-dihydrodiol was 20% while that of the 9,10-dihydrodiol was 46%. At least four phenols were detected among the metabolites of BjF. These were identified as 3-, 4-, 6- and 10-hydroxyBjF based upon comparison of their UV spectra and HPLC retention times with those of synthetic reference standards. BjF-4,5-dione was also identified as a metabolite under these incubation conditions.