America's most polluted cities

Published On: Nov 04 2011 01:51:22 PM CDT   Updated On: Apr 20 2016 01:26:11 PM CDT

Just how dirty is the air you breathe? The American Lung Association has released its latest list of the most polluted U.S. cities.

most polluted - Philadelphia
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12. Philadelphia-Reading-Camden, Pa.-N.J.-Del.-Md.

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