Airborne carcinogens and human cancer.

: There is as yet little convincing evidence that air pollution contributes to cancer risk, save for the strong suspicion of an increase in risk for persons living adjacent to arsenic emitters. The lack of any demonstrated direct and strong relationship between pollution and cancer, as well as the absence of any easily identifiable cancer epidemic in polluted areas, leads us to suspect that if a relationship exists, it is relatively weak and contributes little to the total cancer burden, especially in comparison to hazards such as cigarette smoking. There is a need for further research to verify our conclusions.