New estimates reveal intergenerational economic mobility varies substantially across U.S. counties. The potential role of local environmental health exposures in structuring mobility outcomes has been thus far unexamined, despite mounting evidence that early life exposure to environmental pollutants has lasting impacts for individual human capital development and labor market performance. This study aims to fill this gap by esti- mating the impact of exposure to air pollution in the birth year on the average intergenerational mobility outcomes of children from low-income families as measured in adulthood. We do so by linking measures of intergenerational economic mobility for U.S. county-cohorts born between 1980 and 1986 to the county average concentration of total suspended particulates (TSP) in the birth year. We then estimate multivariate linear regression models that adjust for birth-cohort fixed effects, county-fixed effects and time-varying county-level covariates to address potential confounding. We find higher levels of TSP in birth year is associated with less upward economic mobility for children from low-income families: a one standard deviation increase in TSP levels is associated with a 0.14 point reduction in average income percentile ranking as measured in adulthood. Notably, we find no association for children from high income families. Our findings indicate early life exposure to air pollution may reduce the prospects children from low-income families will achieve upward economic mobility and suggest variation in environmental quality may help explain observed variation in mobility out- comes.