MNN Galleries

7 U.S. cities with the worst air pollution

By: chief on Aug. 4, 2010, 12:20 p.m.
Birmingham, Ala., skyline from Red Mountain

Photo: sailorbill/Flickr

6 of 11

Birmingham, Ala.

Birmingham-Hoover-Cullman, Ala., which earned the seventh spot for year-round particle pollution, also ranked #19 in ozone pollution and #5 in short-term particle pollution.