Where in the world is air pollution a major environmental problem?

Answer 1

In SE Asia, where much of the manufacturing has moved, there is giant brown cloud you can see from space.

Answer 2

Frankly, all over as the stuff travels with the wind...but the micro-environments over cities like Los Angeles, Mexico City, Beijing, New York, etc are especially notorious for air pollution and smog. I mean to the point that there are days people are advised not to go outside because of the health risks. Deaths have been reported from days of severe air pollution (asthmatics and the elderly are especially vulnerable).

Answer 3

europe from what i remember..

mexico city.... large 3rd world countries mostly..