1. Paul B. Allwood is with the Lead Poisoning Prevention and Surveillance Branch (Proposed), National Center for Environmental Health (NCEH), Centers for Disease Control and Prevention (CDC), Atlanta, GA. Henry Falk is with the Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta. Erik Svendsen is with the Division of Environmental Health Science and Practice, NCEH, CDC. Paul B. Allwood and Erik Svendsen are also guest editors for this supplement issue.