MANAGING THE UNMANAGEABLE: WHAT ELSE NEEDS TO BE DONE TO ELIMINATE LEAD EXPOSURE TO CHILDREN?

Albeit slow and not without its challenges, lead (Pb) emissions and sources in the United States (U.S.) have decreased immensely over the past several decades. Despite the prevalence of childhood Pb poisoning throughout the twentieth century, most U.S. children born in the last two decades are significantly better off than their predecessors in regard to Pb exposure. For example, in the 1970’s virtually every child in the U.S. would be considered Pb affected by today’s regulatory blood Pb standard, which is 5 micrograms/deciliter, with some variations among state health departments as to what level a given state begins case management for children. However, the rate of decline in blood Pb levels is not equal across demographic groups, with urban children and children of color exhibiting disproportionately higher average blood Pb levels than their non-urban and white counterparts. In part to address this disparity and to continue reducing population and individual blood Pb levels, many U.S. federal agencies are moving quickly in various “Close to Zero” efforts, including newer regulatory guidance to further limit Pb exposures.

The current state of lead exposure sources is much different than it was 50 years ago. For example, modern atmospheric emissions of Pb in the U.S. are nearly negligible since the banning of leaded gasoline in vehicles and regulatory controls on Pb smelting plants and refineries. This is evident in the rapid decrease of atmospheric Pb concentrations across the U.S. over the last four decades. One of the most significant remaining contributors to air Pb is aviation gasoline (avgas), which is minor compared to former Pb emissions. However, continual exposure risks to legacy Pb sources exist in older homes and urban centers, where leaded paint and/or historically contaminated soils and dusts can still harm children. Thus, while effective in eliminating nearly all primary sources of Pb in the environment, the slow rate of U.S. Pb regulation has led to still-significant legacy sources of Pb in the environment. More work is required to identify where legacy Pb sources are actively exposing children to harm, and substantially more resources, and new approaches, are needed to provide mitigation relief to parents. The presentation reviews the progress made in Pb abatement, its current status, and discusses urban Pb exposure, and future research and regulatory needs.