Tumor-initiating activity, mutagenicity, and metabolism of methylated anthracenes.

Specific methylated derivatives of anthracene are mutagenic in S. typhimurium and have tumor-initiating activity on mouse skin. In this study, the mutagenic activities of 1-, 2-, and 9-methylanthracene, 2,9- and 9,10-dimethylanthracene, 2,9,-10-trimethylanthracene, 2,3,9,10-tetramethylanthracene, and the photo-oxide of 9,10-dimethylanthracene were determined in S. typhimurium TA98 and TA100. The relative tumor-initiating activities of these compounds were also evaluated. These bioassays indicate that increased mutagenic potency and tumor-initiating activity are associated with the presence of a methyl substituent at both the 9- and 10- position of anthracene. Metabolism studies suggest that the biological activity of specific methylated anthracenes may be related to the formation of a simple epoxide adjacent to a peri-methyl substituent.