Environmental lead and childhood blood lead levels in US children: NHANES, 1999-2006.

Although blood lead levels in the United States have fallen dramatically since 1980, there remain subgroups of children with high blood lead levels. We assessed the relationship between environmental lead sources and blood lead levels in children ages 1 to 5 years from the National Health and Nutrition Examination Survey (NHANES), 1999-2006. Modeled ambient air lead levels and industrial lead releases at the census-tract level were assigned to each child's residence with adjustment for confounding factors. Of 3,223 children, 272 (8.4%) had blood lead levels ≥ 5 ug/dL. Industrial releases (2,252 vs 1,696 lbs/mi ² ) and ambient air lead levels (2.28 vs 1.75 ng/m ³ ) were greater in exposed versus unexposed children. For every 10,000 lb/mi ² increase in inverse distance squared weighted exposure, there was a 1.13% increase (95% CI: 0.45%, 1.81%) in blood lead (p = .001).