The role of air pollution and other factors in local variations in general mortality and cancer mortality.

Age-adjusted indices of female cancer mortality and total male mortality in 31 California countries were correlated with air pollution data and with geographic and socioeconomic data from the 1970 United States Census and elsewhere. Air quality was the worst in those countries where socioeconomic status was highest. Cancer mortality showed positive correlations with air pollution levels. Overall male mortality was lower in the affluent but polluted coastal counties. However, when partial correlation coefficients were calculated, controlling for the confounding variables, both overall male mortality and female cancer mortality showed positive correlations with air pollution indices. Stepwise regression analysis produced similar results.