[Carcinogenic efficacy of the transuranium elements americium-241 and curium-244]

Albino female rats were used in the experiments. After a single intraperitoneal administration of 241Am and 244Cm chloride is doses ranging from 0.37 to 185 kBq/kg (14 doses were used) it was established that the doses applied had different effect on the average life of animals. The largest doses shortened and the lowest increased the life span of experimental animals as compared to the controls. The carcinogenic effect of the studied radionuclides and the development of malignant tumors were detected at sufficiently low doses absorbed. Malignant tumors developed in the experimental and control animals were different not only in their incidence but also their localization and spectrum.