Environmental experts warn high percentage of diesel engines in public transport may cause quarter of all air pollution deaths

Usman, 10, has developed asthma and has to use an inhaler when the situation becomes unbearable.

About a third of the air pollution in China's smog-hit capital comes from outside the city, official media reported on Wednesday, citing a pollution watchdog.

As a thick smog hung over Beijing last year, Stephanie Giambruno and her husband decided it was time for her and their two girls to return to the U.S.

It has shrouded England's most famous monuments for days, prompted a rash of calls to the emergency services over health fears and even stopped Prime Minister David Cameron from taking his early mo

Beijing is imposing harsh fines against polluting enterprises in an attempt to cut down on the region's notorious smog.

India may upgrade nationwide fuel standards to eliminate cancer-causing particle emissions from vehicular exhaust by 2021, nine years behind other developing countries such as Turkey and Brazil.

Health experts have warned that the Kathmandu Valley could turn into a city of cardiac and chronic obstructive pulmonary diseases in next five years if nothing is done immediately to curb air pollu