Abstract
Background: PM(2.5) air pollution is a leading cause of disease and death. US air pollutant emissions have declined by 75% since passage of the Clean Air Act in 1970, but the Pittsburgh Metropolitan Statistical Area (MSA) continues to have elevated pollution levels and, in 2025, had the US's 12(th) highest PM(2.5) concentration. Steel mills and coke ovens are major point sources. Objective: To quantify deaths, adverse birth outcomes, and children's IQ loss in the Pittsburgh MSA attributable to PM(2.5) air pollution. Methods: Mean annual PM(2.5) air pollution concentrations were obtained for each census tract in the Pittsburgh MSA from NASA's satellite-based Socioeconomic Data and Applications Center map layers and linked with vital records obtained from the Pennsylvania Department of Health. Exposure-response functions from peer-reviewed literature and EPA's BenMAP software were used to quantify deaths, adverse birth outcomes, and IQ loss attributable to PM(2.5) pollution. Results: The mean annual PM(2.5) concentration in the Pittsburgh MSA was 8.54 μg/m(3). Concentrations across census tracts ranged from 5.74 to 15.90 μg/m(3). Of 27,224 adult deaths in the Pittsburgh MSA in 2019, we estimate that between 3,085 and 3,467 (11.1%-12.5%) were attributable to PM(2.5) pollution. We estimate that 229 premature births, 177 low-weight births, and 12 stillbirths could be attributed to prenatal PM(2.5) exposure. Among the 24,604 children born in the Pittsburgh MSA in 2019, PM(2.5) pollution was linked to the loss of 60,668 full-scale IQ points, resulting in estimated lifetime economic losses of $2.7 billion. Conclusion: In 2019, 11.1%-12.5% of adult deaths in the Pittsburgh MSA, more than 400 adverse birth outcomes, and widespread reductions in children's IQ were attributable to PM(2.5) air pollution. Public policies and strict enforcement that reduce pollutant emissions and improve air quality will improve the health of southwestern Pennsylvania residents, save lives, and be highly cost-effective.