Occupational bladder cancer

4-Aminobiphenyl, 2-naphthylamine, benzidine, 1-naphthylamine and 4-nitrobiphenyl are responsible for occupational bladder cancer in man. Bladder tumors are found in workers who make or use these substances and possibly in those who purify them. The manufacture of auramine and magenta is also associated with the disease. Direct evidence that these chemicals are occupational bladder carcinogens has been obtained from the chemical and rubber industries. Occupational bladder cancer is also a problem in other industries, but in such cases, etiological agents have not been defined. Animal experiments have confirmed that aromatic amines, such as 2-naphthylamine, are carcinogenic and have helped to elucidate their mechanism of action. The problems in protecting workers already exposed to occupational bladder carcinogens and methods which may be used to control the disease are discussed.