The list of the world’s top 20 most polluted cities is out. All but one are in Asia

All but one of the world’s top 20 most polluted cities last year were in Asia, a new study shows. The majority of these cities – 13 – are in the world’s most populous country, India, where booming economic growth is fired largely by coal and where hundreds of millions live in traffic-clogged and congested megacities. Another four are in neighboring Pakistan, with one in China and Kazakhstan