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 .

The World Air Quality Report 2024 shows that Byrnihat, a small town in India, is the most polluted city in the world. Only 17% of global cities meet WHO's air pollution guidelines. Several Indian cities,