Lead exposure and academic achievement: evidence from childhood lead poisoning prevention efforts

Though the adverse consequences of lead exposure in children have been well known for over a century, the recent Flint water crisis has drawn renewed attention to the impacts of lead exposure on human health and development. This study considers connections to educational outcomes, asking whether population-level lead exposure in early childhood influences later academic achievement and racial achievement gaps. It assesses the effectiveness of recent local- and state-level lead hazard control programs in mitigating exposure and uses this source of exogenous variation in early childhood exposure across birth cohorts to draw inferences about the long-term effects of lead on mean student test scores. Our findings indicate that lead hazard control grants reduced lead poisoning incidents by over 70% of the baseline prevalence. And each one percentage point reduction in lead poisoning in early childhood translated to a growth of 0.04 standard deviations in student math test scores and 0.08 standard deviations in student reading scores. This same reduction in lead poisoning narrowed both the white-Hispanic math achievement gap and white-Hispanic reading achievement gap by 0.06 standard deviations, implying important downstream consequences for economic inequality.