Dye stuffs & dyeing industries, rubber, gas & electric cable industries are associated with carcinoma of bladder (transitional cell carcinoma). Bladder cancer is caused by aromatic amines, which are metabolized in the body & excreted in the urine. Possible bladder carcinogens are: Beta-naphthylamines, benzidine, para-amino-diphenyl, auramine & magenta. In this case pt. is exposed to dyes for long duration and is at risk for developing bladder cancer. So, urine tests should be done to see if there is any hematuria, which is the mc symptom of bladder cancer.