The vast majority of these cities – 83 – are in India, and all exceed World Health Organization air quality standards by more than 10 times, according to a report by IQAir, which monitors air quality around the world.
The study looked at fine particulate matter, or PM2.5, which is the smallest pollutant but also the most dangerous. Only 9% of more than 7,800 cities meet the WHO standard of no more than 5 micrograms of PM2.5 per cubic meter per year.
Begusarai, a city of half a million people in the northern Indian state of Bihar, was the world’s most polluted city last year, with an average annual PM2.5 concentration of 118.9, 23 times WHO recommendations. It is followed in the IQAir ranking by the Indian cities of Guwahati, Assam; Delhi and Mullanpur, Punjab.
Across India, 1.3 billion people, or 96% of the population, live in conditions where air quality is seven times higher than WHO recommendations, according to the report.
Central and South Asia were the worst performing regions in the world, containing all four of the most polluted countries last year: Bangladesh, Pakistan, India and Tajikistan. In Southeast Asia, only the Philippines saw annual pollution levels drop from the previous year, the report said.
South Asia is of particular concern: 29 of the 30 most polluted cities are in India, Pakistan and Bangladesh. The report ranks major population centers Lahore at 5th place, New Delhi at 6th place and Dhaka at 24th place.
Only 10 countries and territories had “healthy” air quality: Finland, Estonia, Puerto Rico, Australia, New Zealand, Bermuda, Grenada, Iceland, Mauritius and French Polynesia.
