Comparative Study of the Carcinogenic Activity of Nitrosamines2

Abstract

The carcinogenic activity of dimethyl-, diethyl-, and diphenylnitrosamine and dimethylhydrazine was studied in the rat. The high carcinogenic activity of dimethylnitrosamine and diethylnitrosamine was confirmed; the localization and morphology of the tumors differed from those previously described. Diphenylnitrosamine and dimethylhydrazine had no carcinogenic activity. Dimethylnitrosamine produced tumors with a variety of histological characteristics in the liver, lung, and kidney. Primary malignant tumors arose in 1, 2, or all 3 of these organs of the same rat. In the lung, squamous-cell carcinomas were found either as the only pulmonary tumor or in association with bronchiolar or alveolar adenocarcinoma. Diethyltiitrosamine induced hepatocellular carcinomas in all rats, with metastases into the lung in many instances. One primary kidney tumor was found.