Carcinogenic Activity of Radioactive Phosphorus. ∗

Abstract

Summary

1. Single doses of radioactive phosphorus, administered internally to rats in amounts of from 1 to 3.5 μc/gram body weight, proved carcinogenic. Two types of malignant neoplasms were produced, i.e., osteogenic sarcoma and carcinoma of the face.

2. The incidence of neoplasms ranged from 22 to 50%. The latent period of tumor development was lengthened with smaller doses of P³².

3. Amounts of P³² less than 1 μc/gram body weight failed to induce neoplasms.