Declining Exposures to Lead and Cadmium Contribute to Explain the Reduction of Cardiovascular Mortality in the United States Population, 1988-2004

Abstract

Background. Lead and cadmium exposures have markedly declined in the US following the implementation of large-scale public health policies and could have contributed to the unexplained decline in cardiovascular mortality in US adults. We evaluated if population changes in the distribution of blood lead and urine cadmium levels explain changes in cardiovascular mortality over time in a representative sample of the US general population. Methods. Prospective study in 15,421 adults ≥40 years old who had participated in the National Health and Nutrition Examination Survey 1988-1994 or 1999-2004 and had baseline measures of urine cadmium, blood lead, and cardiovascular risk factors, and mortality follow-up for up to 8 years. We estimated the amount of change in cardiovascular mortality rates comparing 1999-2004 to 1988-1994 that can be independently attributed to changes in blood lead and urine cadmium concentrations. Results. During the study period there was a 43.7% decrease in blood lead and a 23.5% decreas...