MIT researchers and colleagues have identified three new chemical risk factors for bladder cancer in a study involving some 600 people in the Los Angeles area. The work was reported in the Oct. 6 issue of the Journal of the National Cancer Institute.The newly discovered carcinogens are found in cigarette smoke, which is already known to be a major cause of bladder cancer, contributing to at least 50 percent of the approximately 60,000 cases in the United States every year.All three of the new carcinogens, however, were also found to be risk factors for bladder cancer in nonsmokers. Although second-hand smoke is one source of exposure for non-smokers, the researchers say that it is very important to identify the other sources of exposure for nonsmokers.
