NEHA December 2022 Journal of Environmental Health

46 Volume 85 • Number 5 A D VANC EME N T O F T H E PRACTICE  D I RECT FROM U . S . EPA OF F I CE OF RESEARCH AND DEVELOPMENT Actions by the U.S. Environmental Protection Agency (U.S. EPA) and other federal agencies have significantly reduced the use of lead in automotive gasoline, paint, lead-soldered food containers, and new water system components over the past 40 years. Through the collective effort of federal agencies in partnership with local, state, and tribal governments, blood lead levels (BLLs) measured in children have fallen steadily from the 1970s to the 2020s (Egan et al., 2021; President’s Task Force, 2016). One indicator of the success of lead mitigation eŠorts is the Centers for Disease Control and Prevention’s (CDC) reduction of the blood lead reference value (BLRV) from 5.0 to 3.5 μg/dL in October 2021 (Ruckart et al., 2021). The BLRV is a population-based measurement of the 97.5th percentile of BLLs of U.S. children ages 1–5 years. Reduction in the BLRV reflects the decline in BLLs among the children most exposed to lead in the U.S. Despite this progress, lead exposure in children remains a significant public health concern. More than one half million children ages 1–5 years in the U.S. have detectable BLLs and an estimated 6–10 million lead service lines still connect homes to public drinking water systems (Cornwell et al., 2016). Racial disparities in childhood BLLs persist, with higher BLLs observed in non-Hispanic Black children as compared to non-Hispanic White children from 1999 to 2016 (Breysse et al., in press). To address the remaining lead exposure issues in our country, U.S. EPA (2021) developed the draft Strategy to Reduce Lead Exposures and Disparities in U.S. Communities to set goals for an all-of-U.S. EPA and whole-ofU.S.-government plan to strengthen public health protections, promote environmental justice, and address legacy lead contamination for communities with the greatest exposures. Key components of this strategy hinge on the use of science-based approaches to identify lead exposure hotspots, determine site-specific cleanup levels, sequester lead in contaminated soil, identify drinking water lead service lines for replacement, optimize corrosion control for pipes and plumbing fixtures, and support the revisiting of lead rules and guidance in dust, soil, water, and air. Identifying High Lead Exposure Locations Public health professionals tasked with primary prevention must know where lead exposure problems remain and what the key sources of lead exposure are in those locations to proactively prevent and mitigate lead exposures and track where progress has been made in reducing lead exposure (Figure 1). U.S. EPA recently published methods for identifying lead exposure hotspots at the census tract level for targeting actions (Xue et al., 2022; Figure 1). For locations where there are BLL data, U.S. EPA developed two methods of identifying hotspots: 1) a top 20th percentile method identifying census tracts with the highest prevalence of elevated BLLs and 2) a geospatial cluster analysis method. U.S. EPA also explored methods for using exposure-related lead indicators for locations lacking statistically robust and representative Ed i tor ’s Not e : The National Environmental Health Association (NEHA) strives to provide up-to-date and relevant information on environmental health and to build partnerships in the profession. In pursuit of these goals, NEHA has partnered with the Oce of Research and Development (ORD) within the U.S. Environmental Protection Agency (U.S. EPA) to publish two columns a year in the Journal. ORD is the scientific research arm of U.S. EPA. ORD conducts the research for U.S. EPA that provides the foundation for credible decision making to safeguard human health and ecosystems from environmental pollutants. In these columns, authors from ORD will share insights and information about the research being conducted on pressing environmental health issues. The conclusions in these columns are those of the author(s) and do not necessarily represent the ocial position of U.S. EPA. Dr. Andrew Geller is the senior science advisor and executive lead for environmental justice and lead research at U.S. EPA ORD. Science and Science-Based Tools to Address Persistent Hazardous Exposures to Lead Andrew M. Geller, PhD