Millions more Americans breathing dirty air as planet warms, study finds

Forty-three percent of Americans live in places where they're breathing unsafe air, according to American Lung Association

An increasing number of Americans live in places with unhealthy levels of smog or particulate air pollution - both of which are being made worse by climate change, according to a new report.

Air quality in the US has been improving since the 1970s, but that progress may be backsliding and 43% of Americans are now living in places where they are breathing unsafe air, according to the American Lung Association report.