In rats repeatedly treated subcutaneously as infants with adriamycin in 2 cycles of 4 treatments each, the induction of ocular and dental abnormalities and tumors was studied. Cataracts appeared from 18 to 26 days in 80% of CD rats treated with 1.15 mg/kg/day of adriamycin and from 28 to 104 days in 55% of Wistar-Lewis rats given 0.75 mg/kg/day adriamycin. Abnormal growth of incisors was observed in 30% of the CD rats and in 44% of the Wistar-Lewis rats. At lower doses, no such abnormalities were found. At about 1 year after treatment, 100% of the CD rats treated with 0.75 mg/kg/day adriamycin and about 60% of the Wistar-Lewis rats treated with 0.75 and 0.5 mg/kg/day adriamycin developed tumors, which were histologically classified.