MICROSOMAL METABOLISM OF DIBENZ[A,C]ANTHRACENE, DIBENZ[A,H]ANTHRACENE AND DIBENZ[A,J]ANTHRACENE TO BIS-DIHYDRODIOLS AND POLYHYDROXYLATED PRODUCTS

Polar, ethyl acetate soluble metabolites formed in incubations of dibenz[a,c]anthracene (DB[a,c]A), dibenz[a,h]anthracene (DB[a,h]A) and the related DB[a,h]A 3,4-diol and dibenz[a,j]anthracene (DB[a,j]A) with 3-methylcholanthrene (3-MC)-induced rat liver microsomal preparations have been separated by HPLC and examined using fluorescence, UV and NMR spectroscopy. Metabolites with spectral properties consistant with their identification as the 3,4:8,9-bis-diol of DB[a,j]A and a 1,2,3,4,12,13-hexol derived from DB[a,c]A were found. DB[a,h]A was metabolized to three polar products identified as the 3,4:10,11-bis-diol and the related 1,2,3,4,8,9- and 1,2,3,4,10,11-hexols, which were also formed, together with the related 1,2,3,4-tetrol, from the DB[a,h]A 3,4-diol. The possible role of bis-diols in the metabolic activation of these three dibenzanthracenes is discussed.