Delhi is the most polluted city in the world, by now that comes as no surprise. However, what is surprising is that out of the 20 most polluted cities in the world, India accounts for 13 of them. A recent report by the World Health Organisation advises that fine particles of less than 2.5 micrometers in diameter (PM2.5) should not exceed 10 micrograms per cubic metre.

Here is a list of Indian cities with their ranking and PM2.5 levels among the top 20 polluted cities.

#1. Delhi, PM2.5: 153

Source: Indian Express

#2. Patna, PM2.5: 149

Source: Zee News

#3. Gwalior, PM2.5: 144

Source: halabol.com

#4. Raipur, PM2.5: 134

Source: downtoearth.org.in

#9. Ahmedabad, PM2.5: 100

Source: globalgujaratnews.in

#10. Lucknow, PM2.5: 96

Source: prokerala.com

#11. Firozabad, PM2.5: 96

Source: Live Mint

#13. Kanpur, PM2.5: 93

Source: pulitzercenter.org

#14. Amritsar, PM2.5: 92

Source: sikhsangat.org

#15. Ludhiana, PM2.5: 91

Source: wonderslist.com

#18. Allahabad, PM2.5: 88

Source: The Hindu

#19. Agra, PM2.5: 88

Source: susanlyon.com

#20. Khanna, PM2.5: 88

Source: International Business Times

Feature image source: Hindustan Times