India's capital city of New Delhi, choked by rising automobile emissions and construction dust, was named the world's most polluted megacity by the World Health Organisation.
The WHO analysed the levels of the pollutant PM10 in the air in cities with populations above 14 million between 2010 and 2016.
Greater Cairo was the second most polluted large city, with India's other great mega-city of Mumbai ranked fourth on the list and Beijing fifth.
When the health organisation studied data for the smaller and more deadly PM2.5 particulate matter, 14 of the top 15 most polluted cities were in India, with the industrial hub of Kanpur ranked number 1.
Nine out of 10 people around the globe were breathing polluted air, the study said, and that air pollution is responsible for the deaths of seven million people worldwide each year, most of them living in Asia and Africa. Of those deaths, 3.8 million were from indoor air pollution from unhealthy cook stoves, a huge problem in India.
