A new report from the American Lung Association notes a drastic decline in air quality and raises health alarms. Climate change and Trump administration actions, experts warn, will worsen the trend.

Despite improvements in air quality in past decades, 156 million Americans still breathe in too much soot or ozone, says the annual State of the Air report from the American Lung Association.

Weakening or rolling back longstanding environmental regulations would worsen the problem, the American Lung Association assessment says.