Objective: To assess the association between lead exposure and children's physical growth.
Design: Cross-sectional analysis of data from the Third National Health and Nutrition Examination Survey, 1988-1994.
Participants: A total of 4391 non-Hispanic white, non-Hispanic black, and Mexican-American children age 1 to 7 years.
Measurements and results: We investigated the association between blood lead concentration and stature, head circumference, weight, and body mass index with multiple regression analysis adjusting for sex, ethnic group, iron status, dietary intake, medical history, sociodemographic factors, and household characteristics. Blood lead concentration was significantly negatively associated with stature and head circumference. Regression models predicted reductions of 1. 57 cm in stature and 0.52 cm in head circumference for each 0.48 micromol/L (10 micrograms/dL) increase in blood lead concentration. We did not find significant associations between blood lead concentration and weight or body mass index.
Conclusions: The significant negative associations between blood lead concentration and stature and head circumference among children age 1 through 7 years, similar in magnitude to those reported for the Second National Health and Nutrition Examination Survey, 1976-1980, suggest that although mean blood lead concentrations of children have been declining in the United States for 2 decades, lead exposure may continue to affect the growth of some children.