“State of the Air” is the American Lung Association’s annual national air quality “report card.” It uses the most recent air pollution data, compiled by the U.S. Environmental Protection Agency (EPA), for the two most widespread types of pollution—ozone (smog) and particle pollution (PM2.5, also known as soot). The report grades counties and ranks cities and counties based on their scores for ozone, year-round particle pollution and short-term particle pollution levels.
The “State of the Air” 2025 report finds that even after decades of successful efforts to reduce sources of air pollution, 46% of Americans—156.1 million people—are living in places that get failing grades for unhealthy levels of ozone or particle pollution. This is nearly 25 million more people breathing unhealthy air compared to last year’s report, and more than in any other “State of the Air” report in the last ten years.
Extreme heat, drought and wildfires are contributing to worsening levels of air pollution across much of the U.S., exposing a growing proportion of the population to ozone and particle pollution that put their health at risk.