Experimental production of carcinoma with cigarette tar. II. Tests with different mouse strains.

Abstract

Summary 1.Swiss and C57 mice were painted with condensed cigarette smoke in a manner similar to that previously reported for CAF1 mice, with the exception that the tar had been standing in acetone for a longer period of time in the second experiment. 2.Among 86 Swiss mice 22 papillomas and twelve carcinomas were noted. The results for C57 mice were ten papillomas and two carcinomas among 89 mice. 3.The data show Swiss mice to be a more susceptible strain to cigarette tar painting than C57 mice. 4.Application of croton oil, in addition to cigarette tar, appears to accelerate the formation of lesions in Swiss and C57 mice. 5.The possibility is discussed that the higher percentage of lesions previously reported among CAF1 mice could be on the basis that that experiment was conducted with tar that had been standing in acetone for a shorter period of time before use than that used in the second experiment. 6.It is suggested that in experiments using condensed cigarette tar as a possible carcinogen the tar be stored refrigerated in undiluted form, in brown bottles, and that the solutions to be used for the applications be prepared at biweekly intervals.