Carcinogenicity of Methylchrysenes

Abstract
Methylchrysenes are present in tobacco smoke and are suspected to contribute to the tumorigenicity of this inhalant. Chrysene and the six isomeric methylchrysenes were obtained in high purity (〉99.9 percent); they were tested on mouse skin for tumor initiating activity and carcinogenicity. The 3- and 6-methylchrysenes are strong tumor initiators, whereas the other five chrysenes have moderate initiatinig activity. 5-Methylchrysene is a strong carcinogen; the other chrysenes are inactive or weak carcinogens.