[Occupational bladder tumors among persons subjected to carcinogenic amino compound exposure: the epidemiology and prevention].

The epidemiology of bladder tumors was examined among the subjects exposed to cancerogenic amino compounds such as beta-naphthylamine and benzidine (Group 1). The workers from other chemical shops of the plant were enrolled as a control group (Group 2); those from service shops (Group 3) and white-collar ones (Group 4) were also included. A total examined group comprised 4,624 subjects followed up in 1975-1979. The age- and sex-adjusted bladder tumor morbidity rates in males were 48.3, 11.0, 6.9 in Groups 1, 2, and 3, respectively (the normal rate, 5.6 per 100,000), while the respective figures in females were 75.0 and 18.2 in Groups 1 and 2, respectively (the normal rate, 1.1 per 100,000). No bladder cancer was recorded among the male workers from service shops and female service and white-collar workers (the expected rate was less than 1). Calculating the bladder cancer morbidity rates by the common standard indices indicated that there was no excess of the rates typical of the disease for males as compared to females, which is generally observed on exposure to potent cancerogenic substances. There was an increase in the latent period of urinary bladder cancer progression from 13.0 to 18.6 in males and to 20.4 in females who had been exposed to benzidine, as compared to the 1950s and 1960s. The mean latent period was 24.2 years in females and 21.5 in males who had been exposed to beta-naphthylamine. 42% of all those who had diagnosed bladder cancer had not come in direct contact with the above cancerogenic agents.(ABSTRACT TRUNCATED AT 250 WORDS)