Bladder tumors can develop on the lining of the bladder wall (superficial disease) or extend into the bladder wall (invasive disease) and quickly spread to the underlying muscle. Most bladder tumors arise from the specialized tissue lining the interior of the bladder (transitional epithelium). Typically, patients with bladder cancer have blood in the urine or symptoms of urinary tract irritability. However, some have no symptoms at all. Some bladder cancers are the direct result of exposure to carcinogens from chemicals in the workplace. In addition, smoking is an important risk factor for the disease.
Although bladder cancer is a relatively rare disease, there have been many reports of occupational bladder cancer in the chemical industry in many different countries. Aniline, benzidine, and 1- and 2- naphthylamine are likely causative agents. The manufacture of auramine and magenta presents excess risk as a bladder cancer hazard.