EFFECT OF INGESTED ARSENIC ON METHYLCHOLANTHRENE-INDUCED SKIN TUMORS IN MICE

Three strains of mice (C × C3H, DBA, and Balb/C) were selected on the basis of differing vigor or potentiaiity for cutaneous tumor development or both. These animals were fed arsenic trioxide in their drinking water in a concentration of 0.01%. Cutaneous tumors were initiated by the topical application of methylcholanthrene disks and promoted by transplantation. Although arsenic treatment appeared to increase the number of papillomas produced in the DBA strain, the effect was not statistically significant. The C × C3H mice, however, displayed an opposite effect, in that arsenic treatment resulted in a decrease in the number of papillomas produced. This effect was statistically significant with a P value < 0.05. © 1969 Taylor & Francis Group, LLC.