Comparison of the effects of the US Clean Air Act and of smoking prevention and cessation efforts on the risk of acute myelogenous leukemia

Objectives: We used 2 approaches based on published information to compare the impacts on leukemia incidence and benzene exposure of the 1990 US Clean Air Act (CAA) amendments and smoking prevention and cessation efforts. Methods: We extrapolated leukemia mortality related to community air pollution levels and to cigarette smoking from data from the US Environmental Protection Agency and the US Surgeon General. We also estimated relative decline in total exposures to benzene (a known human leukemogen) owing to the CAA amendments and to smoking prevention and cessation efforts. Results: We estimated that because of the CAA, there will be approximately 300 fewer leukemia deaths in the United States during the period 2000 through 2020. During the closest comparable period (1987-2007), we estimated that decline in cigarette smoking led to 7120 fewer leukemia deaths, of which 1282 to 3702 were attributable to benzene. Similarly, the decline in smoking led to about a tenfold greater decrease in total-population benzene exposure than did the 1990 CAA amendments. Conclusions: Both the CAA and smoking cessation activities contribute to a decrease in leukemia incidence. Smoking cessation activities have had a greater effect in the past.