Inhibition of DMBA carcinogenesis of hamster buccal pouch by phenanthrene and dimethylnaphthalene.

Phenanthrene (Phe) and to a lesser degree 1,4-dimethylnaphthalene (DMeN) were each found to retard the development of epidermoid carcinomas in hamster buccal pouch induced by the thrice weekly application of a 0.5 per cent solution of 7,12-dimethylbenz[a]anthracene (DMBA) in heavy mineral oil.