Statistical studies of mortality and air pollution multiple regression analyses by cause of death

Multiple regression analyses are presented relating community air quality, socio-economic variables, and mortality rates for all cancers, respiratory system cancer, respiratory disease, and external causes, for U.S. cities for 1969–1971. Socioeconomic variables included an index of cigarette smoking (by state), which was usually highly significant. Most air pollution variables were not significant, however, with the exception of the trace metal manganese, which was associated with cancers and respiratory disease. Because of the low ambient concentrations in this study, it is likely that manganese is serving as a surrogate for some other effect, such as occupational influences for example.