Question

In what areas of a city would the highest levels of pollution be found

Answer 1

FROM GOOGLE RESEARCH:

22 of world's 30 most polluted cities are in India, Greenpeace says. Twenty-two of the world's 30 worst cities for air pollution are in India, according to a new report, with Delhi again ranked the world's most polluted capital.

Answer 2

Gas bases, Power Plants, etc