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The Top 10 Cities for Air Quality

To coincide with Scientific American's "Cities" special topic issue, we assembled recently compiled lists ranking U.S. cities on aspects of green living, pollution, health and technology. Today, we feature lists that rank cities based on air pollution, Part 3 of 5

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Top 10 Most Polluted Air

  • Bakersfield–Delano, Calif.

  • Visalia–Porterville, Calif.

  • Phoenix–Mesa–Glendale, Ariz.

  • Los Angeles–Long Beach–Riverside, Calif.

  • Hanford–Corcoran, Calif.

  • Fresno–Madera, Calif.

  • Pittsburgh–New Castle, Pa.

  • Birmingham–Hoover–Cullman, Ala.

  • Cincinnati–Middletown–Wilmington, Ohio–Ky.–Ind.

  • Louisville-Jefferson County-Elizabethtown-Scottsburg, Ky.-Ind; Modesto, Calif.

Every year the American Lung Association (ALA) prepares a "State of the Air" report, using data from the U.S. Environmental Protection Agency. The agency measures the air quality of U.S. cities in terms of ozone, year-round particle pollution and short-term particle pollution. The listed cities had the most annual particle pollution in the air.


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Top 10 Cleanest Air

  • Cheyenne, Wyo.

  • Santa Fe–Espanola, N.M.

  • Tucson, Ariz.

  • Honolulu

  • Great Falls, Mont.

  • Anchorage, Alaska

  • Amarillo, Texas

  • Albuquerque, N.M.

  • Redding, Calif.

  • Salinas, Calif.

As part of the "State of the Air" report, the ALA also lists the cities with the least ozone and particle pollution. These cities had the cleanest air quality in terms of year-round particle pollution.

Tomorrow: Part 4—The Top 10 Tech-Friendly Cities Yesterday: Part 2—The Top 10 Healthiest Cities

Sophie Bushwick was formerly the technology editor at Scientific American. She makes frequent appearances on radio shows such as Science Friday and television networks, including CBS, MSNBC and National Geographic. She has more than a decade of experience as a science journalist based in New York City and previously worked at outlets such as Popular Science,Discover and Gizmodo. Follow Bushwick on X (formerly Twitter) @sophiebushwick

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