Fluoro-substituted N-nitrosamines. 5. Carcinogenicity of n-nitroso-bis-(4,4,4-trifluoro-n-butyl)amine in rats.

N-Nitroso-bis-(4,4,4-trifluoro-n-butyl)amine (F-6-NDBA) has been synthesized as a derivative of the rat urinary bladder carcinogen N-nitrosodibutylamine (NDBA). Its chronic administration by gavage to Sprague-Dawley rats induced a significant incidence of malignant tumors of the liver and the lungs. Tumors in the liver were diagnosed as multifocal hepatocellular carcinomas and those of the lungs were mainly squamous cell carcinomas. No tumors were observed in the urinary bladder. This confirms earlier results from metabolism and animal carcinogenicity experiments indicating the importance of metabolic oxidation at the terminal carbon atom of NDBA for its organ-specific effects. This metabolic omega-oxidation is blocked in F-6-NDBA.