Estimating effects of soil remediation on children’s blood lead near a former lead smelter in Omaha NE, U.S.

TPS 631: Metals and health 1, Johan Friso Foyer, Floor 1, August 27, 2019, 3:00 PM - 4:30 PM Background: Lead is a toxic metal known to affect cognitive development in children even at low exposure levels. We examined the relationship between remediation activities, soil concentrations and children’s blood lead levels among children living near a lead smelter that operated from 1871-1997 in Omaha, Nebraska. Methods: We assembled a cohort of children with blood lead measurements from a surveillance program and linked them to U.S. Environmental Protection Agency databases having residential soil lead measurements and soil remediation dates. Controlling for temporal trends and children’s demographics, we estimated associations between elevated blood lead (EBL, >3.5 µg/dl) and soil lead concentration using logistic regression accounting for within-child correlations. Analyses comparing children’s pre- and post-remediation EBL to estimate effects of soil lead remediation are underway. Results: Capillary blood lead samples (n=217,480) were collected from children (n=117,799) in Omaha from 1995-2016. Of these children, soil lead concentrations were available for 44,153 and among these 16,927 had soil remediation. Preliminary analysis indicated that the percent of EBL samples dropped from 58.2% in 1995 to 8% in 2016. We observed a positive association between pre-remediation EBL and pre-remediation soil lead concentration [1.44 (1.39, 1.50), odds ratio (95% CI) per unit increase in log (base e) soil lead concentration]. The association was weaker between post-remediation EBL and post-remediation soil lead concentrations [1.08 (0.99, 1.17), odds ratio (95% CI)]. Conclusions: Our analyses suggest a large decrease in blood lead concentrations over time in children living near a former smelter, which could be associated, in part, with soil remediation. The views expressed in this presentation are those of the authors and do not necessarily represent the views or policies of the U.S. Environmental Protection Agency.