Occupational exposure to hydrazine and subsequent risk of cancer.

Four hundred and twenty seven men with varying degrees of occupational exposure to hydrazine, a weak animal carcinogen, were studied to see if they provided any evidence of carcinogenicity to man. The observed mortality was close to that expected for lung cancer, other cancers, and all other causes, irrespective of the level of exposure. There were 49 deaths (61.47 expected) from all causes including five deaths from lung cancer (6.65 expected). The results show that no obvious hazards associated with hydrazine exposure have yet appeared but because of the small number of men studied they can only exclude gross hazards.