
Air in the U.S. has gotten cleaner for decades, adding years to people's lives and preventing millions of asthma attacks, but nearly half of Americans still live with unhealthy air pollution, a new report finds.
The report comes as the Trump administration is considering rolling back some key air quality regulations.
Air quality across the country has improved dramatically since regulations like the Clean Air Act were put in place in the 1970s to govern sources of pollution like coal-fired power plants and emissions from diesel trucks. Despite that progress, the air is still unhealthy and polluted in many parts of the country. In 2023, nearly half of the country's inhabitants — 156 million people — lived in places heavy in smog or soot pollution that harms their lungs, hearts, and brains, according to the newest edition of the American Lung Association's State of the Air report.