Disparities in PM2.5 air pollution in the United States Jul 31, 2020 By Jay ShimshackJonathan ColmerIan HardmanJohn Voorheis Disparities in PM2.5 air pollution in the United States Air pollution at any given time is unequally distributed across locations. Average concentrations of fine particulate matter smaller than 2.5 micrometers in diameter (PM2.5) have fallen over time. However, we do not know how the spatial distribution of PM2.5 has evolved. Here, we provide early evidence. We combine 36 years of PM2.5 concentrations measured over ~8.6 million grid cells with geographic, economic, and demographic data from ~65,000 U.S. census tracts. We show that differences in PM2.5 between more and less polluted areas declined substantially between 1981 and 2016. However, the most polluted census tracts in 1981 remained the most polluted in 2016. The least polluted census tracts in 1981 remained the least polluted in 2016. The most exposed subpopulations in 1981 remained the most exposed in 2016. Overall, absolute disparities have fallen, but relative disparities persist. Read in Science Magazine Jay Shimshack Jay Shimshack is Professor of Public Policy and Economics, and the Associate Dean for Academic Affairs at the University of Virginia’s Frank Batten School. He received a Ph.D. from U.C. Berkeley and a B.S. from Cornell University. Prior to joining UVa, Shimshack held positions at Tulane University and Tufts University and a visiting faculty fellowship at the University of Michigan. His major fields are environmental regulation, environmental economics, corporate social behavior, and applied microeconomics for public policy. Read full bio Jonathan Colmer Ian Hardman John Voorheis Related Content Jay Shimshack Costly Sanctions and the Treatment of Frequent Violators in Regulatory Settings Research Regulators typically treat frequent violators more harshly. When does such harsh treatment maximize overall compliance? Disaster Preparedness and Disaster Response: Evidence from Sales of Emergency Supplies Before and After Hurricanes Research Government information warns households to acquire emergency supplies as hurricanes threaten and directs households to stay off roads after hurricanes make landfall. Do households follow this advice? Batten's New Postdoctoral Researchers to Focus on Diversity, Social Identity News The School's new postdoctoral fellows will investigate perceptions of minorities in academia and the workplace, among other subjects. Batten Professor Selected as University of Tulsa’s Next President News Brad Carson, a native Oklahoman who represented the state’s 2nd Congressional District in the House of Representatives, taught courses related to national security and public sector innovation at Batten.