22 out of 30 cities that have the world’s worst air pollution are in India, says report

India has dominated the rankings of a new report on air pollution, with 22 out of the top 30 most polluted cities in the world located in the South Asian nation.

The readings from 3,000 cities, analysed by Greenpeace and AirVisual, were measured against the World Health Organisation’s annual exposure guideline for PM2.5 fine particulate matter – tiny airborne particles, measuring about a 40th of the width of a strand of human hair, that are linked to a wide range of health problems.

All the measured cities in the Middle East and Africa exceeded the WHO guidelines, as well as 99 per cent of cities in South Asia and 89 per cent in East Asia. The only other country to feature in the top 30 is China.

The Indian tech hub of Gurugram – a city southwest of Delhi which is home to international firms such as Uber and TripAdvisor – ranked as most polluted in the world. Delhi is ranked 11th. Faisalabad in Pakistan is ranked third, and Dhaka in Bangladesh is ranked 17th.

Chinese cities appear five times in the list, including Hotan in the western Xinjiang province (eighth) and the ancient Silk Road city of Kashgar (19th).

Since many cities, particularly in Africa, do not have up-to-date public air quality information, the actual number of cities exceeding PM2.5 thresholds is expected to be much higher, the report authors said.