Human exposure to lead in the environment causes irreversible impairment of intellectual function. In Bangladesh, where some rural residents have unexpectedly high levels of lead in their blood, the source is proving difficult to pinpoint. This project will evaluate the severity of lead poisoning in rural Bangladesh and identify the pathway of exposure to help develop of focused prevention strategies. This study is designed to provide important evidence to support policy responses that reduce lead from the environment, not only in Bangladesh but also in other regions where lead contamination is a known risk to health and development.