Intellectual Impairment in Children with Blood Lead Concentrations below 10 μg per Deciliter

From the Division of Nutritional Sciences (R.L.C.) and the Department of Human Development (C.R.H.), College of Human Ecology, Cornell University, Ithaca, N.Y.; the Departments of Environmental Medicine (D.A.C.-S.) and Biostatistics and Computational Biology (C.C.), University of Rochester School of Medicine, Rochester, N.Y.; the Division of Epidemiology, Statistics, and Prevention, National Institute of Child Health and Human Development, National Institutes of Health, Department of Health and Human Services, Bethesda, Md. (C.C.); the Department of Epidemiology, School of Public Health and Community Medicine, University of Washington, Seattle (T.A.J.); and Cincinnati Children’s Environmental Health Center, Children’s Hospital Medical Center, Cincinnati (B.P.L.). Address reprint requests to Dr. Canfield at the Division of Nutritional Sciences, College of Human Ecology, Cornell University, Ithaca, NY 14853, or at [email protected]. N Engl J Med 2003;348:1517-26. Copyright © 2003 Massachusetts Medical Society. background Despite dramatic declines in children’s blood lead concentrations and a lowering of the Centers for Disease Control and Prevention’s level of concern to 10 μg per deciliter (0.483 μmol per liter), little is known about children’s neurobehavioral functioning at lead concentrations below this level.