Abstract
The plan of a study of cardiovascular disease mortality in relation to air pollution, designed to evaluate socioeconomic factors as well as degree of exposure to air pollutants, has been described. When the degree of exposure to air pollutants was kept constant a generally regular pattern of an inverse relationship between socioeconomic class and mortality rates for cardiovascular diseases was observed for the Nashville SMSA for a 12-year period, 1949 to 1960. An exception was arteriosclerotic heart disease which showed a direct relationship.