Lead in Drinking Water and Birth Outcomes: A Tale of Two Water Treatment Plants

Abstract

The recent drinking water crisis in Newark, New Jersey's largest city, has renewed concerns about the lead-in-water crisis becoming a persistent and widespread problem owing to the nation's aging infrastructure. We exploit a unique natural experiment in Newark, which exogenously exposed some women in the city to higher levels of lead in tap water but not others, to identify a causal effect of prenatal lead exposure on fetal health. Using birth data that contain information on mothers' exact residential addresses, we find robust and consistent evidence that prenatal exposure to lead significantly raises the probability of low birth weight or preterm births by approximately 1.4 to 1.9 percentage points (14-22 percent), and the adverse effects are largely concentrated among mothers of lower socioeconomic status. Our findings have important policy implications in light of the long-term impact of compromised health at birth and the substantial number of lead water pipes that remain in use as part of our aging infrastructure.