Heavy lead exposure has been connected to cardiovascular disease, but modest exposures encountered in the general environment have not been associated previously with disease risk. The relationship between blood lead levels and blood pressures was examined using data from the second National Health and Nutrition Examination Survey. A direct relationship was found between blood lead levels and systolic and diastolic pressures for men and women and for white and black persons aged 12 to 74 years. Blood lead levels were significantly higher in younger men and women (aged 21 to 55 years) with high blood pressure, but not in older men or women (aged 56 to 74 years). In multiple regression analyses, the relationship of blood lead to blood pressure was independent of other variables for men, but not for women. Dietary calcium and serum zinc levels were inversely related to blood pressure.