Global cities with the best and worst air quality

Kailua-Kona in Hawaii is one of the towns and cities with the best air quality in the world. Photo: AFP

The British company HouseFresh has drawn up a map of the 50 most polluted cities in the world. While the worst offenders are all located in Asia, it is a city in Australia that wins the prize for the "cleanest air".

Natural disasters such as forest fires or sandstorms play a major role in the air quality of the cities featured in this study.