The metabolites of benz(j)aceanthrylene (B(j)A) and benz(l)aceanthrylene (B(l)A) produced by incubation with liver S9 proteins from rats induced with Aroclor-1254 and phenobarbital have been studied. Aroclor-1254 and phenobarbital induced rat liver S9 each metabolized B(j)A to trans-B(j)A-1,2-dihydrodiol, B(j)A-9,10-dihydrodiol, B(j)A-11,12-dihydrodiol, and 10-hydroxy-B(j)A. The major metabolite formed (58-60%) by both induced S9 preparations was trans-B(j)A-1,2-dihydrodiol, the cyclopentra-ring dihydrodiol while oxidation at the k-region or the proximal-bay region was minor. There were no statistical differences in individual or total B(j)A metabolite rates between the two induced S9 preparations. Both induced S9s produced similar rates of B(l)A metabolites except for B(l)A-7,8-dihydrodiol formation which was higher for Aroclor-1254 induced S9.