This time, the list comes from Forbes, which crunched the data from the annual American Lung Association report on national air quality. And as usual, it's ugly. Grist condensed the list into a top 20 countdown, and here 'tis:
20. Cleveland, Ohio
19. Indianapolis, Ind.
18. Houston, Tx.
17. Salt Lake City, Utah
16. Washington, D.C.
15. Knoxville, Tenn.
14. New York, N.Y.
13. Cincinnatti, Ohio
12. Philadelphia, Pa.
11. Louisville, Ky.
10. Sacramento, Calif.
9. San Diego, Calif.
8. Phoenix, Ariz.
7. Birmingham, Ala.
6. Modesto, Calif.
5. Pittsburgh, Pa.
4. Fresno, Calif.
3. Visalia, Calif.
2. Los Angeles, Calif.
1. Bakersfield, Calif.
