Asbestos as an air pollutant and synergism with smoking.

For many years the health consequences of asbestos exposure, including an overall mortality experience of approximately 50% from cancer among occupationally exposed individuals, have been well documented worldwide. Less well appreciated are the lessons to be learned from data available concerning outdoor asbestos air pollution and, of perhaps greater concern, the risks in certain indoor environments contaminated by this useful mineral. The biologically complex issue of carcinogenic synergism has been clearly demonstrated for cigarette smoking, asbestos-exposed individuals. Prevention of cancer among those exposed to asbestos not only requires efforts to minimize such exposure, but also requires strong antismoking measures among those exposed.