Conference Agenda

We study the link between race and air pollution in Mexico. Combining satellite-based estimates of PM2.5 (1998–2022) with census data on household indigeneity, we compare average annual pollution levels between predominantly Indigenous and non-Indigenous municipalities. Our estimates suggest a persistent conditional exposure gap of more than one microgram per cubic meter. We then decompose this gap by examining the mechanisms that support it, including cooking fuel choice, agricultural burning, industrial siting, and local atmospheric conditions. Mechanism-specific conditional differences indicate that differences in cooking fuel explain up to fourteen percent of the gap, while atmospheric and orographic conditions account for up to forty percent. We posit that these orographic differences relate to the historical displacement of Indigenous populations into rugged terrain, which reduces the planetary boundary layer height and traps pollutants. To our knowledge, this is the first study to connect historical displacement with contemporary environmental justice. Finally, we estimate the health consequences of the estimated gap by calculating differences in the mortality effects of PM2.5 between Indigenous and non-Indigenous municipalities using a control-function approach that instruments PM2.5 with boundary-layer height. Results suggest a higher marginal effect of PM2.5 on mortality in Indigenous municipalities. Policy simulations imply that equating the share of people cooking with bio-fuels between Indigenous and non-Indigenous municipalities could prevent around 120 premature deaths annually, with benefits of up to USD 26 million.