Project Summary The objective of this project is to evaluate the contribution of racial/ethnic and socioeconomic inequalities in public drinking water contaminant exposures to in utero water contaminant exposures and subsequent adverse birth outcomes across the United States (US). Potential disparities in public drinking water contaminant exposures have not been comprehensively characterized across the US. Such disparities in public drinking water contaminant exposures may directly contribute to inequalities in in utero exposures and inequalities in adverse birth outcomes. This proposal aims to (1) evaluate racial/ethnic and socioeconomic inequalities in drinking water contaminant exposures across the US by developing novel nationwide public drinking water contaminant exposure estimates for over eighty regulated contaminants; (2) evaluate the contribution of estimated public drinking water metal exposures to measured in utero internal dose and infant health outcomes across three diverse birth cohorts; and (3) evaluate the impact of changes in national public drinking water regulations on infant health outcomes using a difference-in-differences approach, which can characterize the impact of federal drinking water regulatory changes on diverse racial/ethnic and socioeconomic subgroups in the US. In Aim 1, novel nationwide public drinking water contaminant exposure estimates will be derived primarily using data from the US Environmental Protection Agency's Six Year Review of Contaminant Occurrence database, which contains compliance monitoring data for over 95% of public drinking water systems throughout the US. In Aim 2, novel public drinking water contaminant exposure estimates from Aim 1 are assigned to maternal-infant dyads in several diverse birth cohorts in the Environmental influences on Child Health Outcomes (ECHO) nationwide consortium, a pioneering NIH funded consortium. In Aim 3, novel public drinking water contaminant exposure estimates from Aim 1 are assigned to birth records from the California Comprehensive Birth File to evaluate the impact of reducing water contaminant exposures (via federal regulatory change) on adverse birth outcomes. The proposed study responds directly to the NIH Strategic Plan 2020 aim to “Develop evidence- based interventions to reduce health disparities,” including “Understanding mechanisms that lead to health disparities by race/ethnicity and socioeconomic status.”

Project Narrative The proximal mechanisms driving racial/ethnic and socioeconomic inequalities in infant health and their impact across the lifespan remain poorly understood. The proposed project evaluates the contribution of inequalities and injustices in public drinking water contaminant exposure to potential inequalities in in utero contaminant exposures and subsequent inequalities in adverse birth outcomes. Characterizing the contribution of public drinking water inequalities to racial/ethnic and socioeconomic health disparities can have major implications for public drinking water regulatory policy in the US.