This testimony addressed issues surrounding workplace exposure to potential carcinogens and indicated that investment in occupational cancer research has substantial benefit to society. Of the approximately 500,000 people who die from cancer in the United States each year, it was conservatively estimated that 4% of these cancers originated from exposures in the workplace. About 10% of lung cancers, 21% of bladder cancers, and nearly 100% of mesotheliomas in the United States were thought to be related to occupational exposures to recognized carcinogens. For occupational lung cancer alone the direct medical costs total 500 million dollars. NIOSH estimates that at least several million workers in the United States are potentially exposed to the 180 substances that the International Agency for Research on Cancer has classified as agents that are carcinogenic to humans. NIOSH has used surveillance, laboratory and field research, identification of control technology solutions, and information dissemination as a comprehensive strategy to prevent workplace exposures and work related cancer. OSHA regulates 18 substances or classes of compounds that are potential occupational carcinogens. NIOSH works with small businesses to evaluate hazards and develop cost effective controls.