Working Paper: NBER ID: w24607
Authors: Karen Clay; Margarita Portnykh; Edson Severnini
Abstract: Using U.S county level data on lead in air for 1978-1988, this paper provides the first causal evidence on the effects of airborne lead exposure on the general fertility rate and the completed fertility rate in the broad population. Instrumental variable estimates show the increase in completed fertility implied by the average observed decrease in airborne lead is 0.14 children per woman, which is 6.4 percent of mean fertility. To explore the current relevance of our findings, we estimate the effect of lead historically accumulated in topsoil on fertility in the 2000s. The results suggest that lead may continue to impair fertility today, both in the United States and in other countries that have significant amounts of lead in topsoil.
Keywords: lead exposure; fertility rates; air pollution; public health
JEL Codes: I18; J13; Q52; Q53
Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.
| Cause | Effect |
|---|---|
| lead exposure (L72) | general fertility rate (J19) |
| lead exposure (L72) | completed fertility (J13) |
| decrease in airborne lead (Q53) | general fertility rate (J19) |
| counties with lead concentrations above median (Y10) | general fertility rate (J19) |
| regulatory changes in lead standards (L51) | exogenous variation in lead exposure (J79) |