The majority of the world is breathing in dirty air, according to the latest air quality report. So where does the U.S. rank?

Air pollution is a major killer, with studies estimating it kills 9 million people worldwide a year and sickens millions more ...

India had six of the nine most polluted cities worldwide, a new report from a Swiss-based database found. View on euronews ...

The U.S. has committed more than any other country, but Europe has 'clearly overtaken' the U.S. as Ukraine’s biggest benefactor.