Recent Increases In Air Pollution: Evidence And Implications For Mortality

After declining by 27.4 percent from 2009 to 2016, annual average fine particulate matter (PM2.5) in the United States in counties with monitors increased by 5.7 percent between 2016 and 2018. Increases occurred in multiple census regions and in counties that were in and out of attainment with National Ambient Air Quality Standards. This article explores channels through which the increase may have occurred, including increases in economic activity, increases in wildfires, and decreases in Clean Air Act enforcement actions. We find that the health implications of the increase in PM2.5 are significant. The increase was associated with 9,700 additional premature deaths between 2016 and 2018, which, based on conventional valuation methods, represent damages of $89 billion.