Around 156 million Americans, nearly half of the US population, now live in areas with unhealthy levels of air pollution, part of a trend toward declining air quality as climate change-related extreme weather events like wildfires occur more frequently.
That’s according to the 2025 State of the Air report from the American Lung Association, which each year tracks air quality around the nation. The report, released Wednesday, focuses on two common and dangerous pollutants: ozone and fine particles. The number of Americans exposed to high levels of these has risen by