A 'World Air Quality Report' released by Swiss firm IQAir has placed 64 Indian cities in the top 100 most polluted cities of the world.
The report has studied data taken from 7,300 cities across 131 countries and is based on the PM2.5 levels - tiny pollutant particles or droplets that are two and a half microns or less in width.
In the list led by Pakistan's Lahore, India's Delhi is the 4th most polluted city after Rajasthan's Bhiwadi. Delhi's PM2.5 levels stand at 92.6 micrograms while Bhiwadi is marginally higher at 92.7 micrograms.
There are 4 other Indian cities in the top 10, but it is interesting to note that the report has analysed 'greater' Delhi and the Indian capital New Delhi separately, in terms of pollution levels. New Delhi is ranked 9th on the list with the PM2.5 level at 89.1 micrograms.
Five cities from the state of Bihar have been listed in the top 20 apart from Haryana's Dharuhera, Faridabad and Bahadurgarh, UP's Muzaffarnagar, Ghaziabad and Greater Noida, and Punjab's Faisalabad.
According to the report, the economic cost of India's air pollution amounts to $150 billion, which it has attributed majorly to vehicular emissions. It also lists industrial units, coal-fired power plants and biomass burning as other causes of pollution in India.
In the list of the world's most polluted countries, India has dropped to 8th place from fifth in 2021. Despite a decline in India's PM 2.5 level, it is still 10 times over the World Health Organisation's safe limit.