Causes of Pollution 

Find out more about the city you live in and its causes of air pollution: 

Delhi is the most polluted mega-city in the world, and 14 of the 15 most polluted cities in the world are in India. So what exactly is causing this pollution?


Chicago is the 22nd most polluted city in the United States, moving up 4 spots from 26th just last year. Find out why.