The American Lung Association's study of air pollution in American metropolitan areas discovered that Los Angeles' air continues to be the nation's worst but the number of critically polluted days is on the downturn. Following L.A. were 2) Pittsburgh (Pennsylvania), 3) Bakersfield (California), 4) Birmingham (Alabama), and 5) Detroit (Michigan).

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And #2 Pittsburgh is suppose to be the best place to live in America, huh.
We need to stop driving all cars. WOrldwide. and no more airplane flights. See my blog.