One-third of Americans live in regions that saw more than 100 days with unhealthy air quality in 2018, according to a new national report from Environment America, U.S. Public Interest Research Group (U.S. PIRG) and Frontier Group.
The report analyzed U.S. Environmental Protection Agency (EPA) pollution records for ground-level ozone (or smog) and fine particulate pollution. In all, 89 urban areas and 12 rural counties, with a combined population of 108 million people, had more than 100 days that violated federal air quality standards.
Among major metro areas, Riverside, CA saw the most days with unhealthy levels of both pollutants, with 227 total in 2018. The other most populated metro regions that saw high levels of pollution were: Los Angeles; Chicago; Dallas-Forth Worth; Houston; Atlanta; Phoenix; Detroit; San Diego, CA; and Denver, CO.
The report serves as a reminder that even though there have been significant efforts to improve air quality in the past few decades, Americans are still breathing unhealthy levels of pollution. The American Lung Association reported last year in its annual State of the Air report that the number of Americans in areas with unsafe air quality was rising, and had reached 141 million people between 2015 and 2017.