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Best & Worst Cities for Ozone Pollution


This information has been reviewed and approved by Anthony Gerber, MD, PhD (July 2025).


Summary: Best and Worst Cities for Ozone Pollution

Worst Cities by Ozone

1: Los Angeles-Long Beach, CA
2: Visalia, CA
3: Bakersfield-Delano, CA
4: Phoenix-Mesa, AZ
5: Fresno-Hanford-Corcoran, CA
6: Denver-Aurora-Greeley, CO
7: Houston-Pasadena, TX
8: San Diego-Chula Vista-Carlsbad, CA
9: Salt Lake City-Provo-Orem, UT-ID
10: Dallas-Fort Worth, TX-OK
11: Sacramento-Roseville, CA
12: Las Vegas-Henderson, NV
13: Fort Collins-Loveland, CO
14: San Jose-San Francisco-Oakland, CA
15: Chicago-Naperville, IL-IN-WI
16: New York-Newark, NY-NJ-CT-PA
17: El Centro, CA
18: El Paso-Las Cruces, TX-NM
19: Tulsa-Bartlesville-Muskogee, OK
20: San Antonio-New Braunfels-Kerrville, TX
21: St. Louis-St. Charles-Farmington, MO-IL
22: Albuquerque-Santa Fe-Los Alamos, NM
23: Colorado Springs, CO
24: Redding-Red Bluff, CA
25: Sheboygan, WI

Cleanest Cities by Ozone

1. Augusta-Richmond County, GA-SC
2. Bangor, ME
3. Bellingham, WA
4. Brunswick-St. Simons, GA
5. Charleston-Huntington-Ashland, WV-OH-KY
6. Charlottesville, VA
7. Crestview-Fort Walton Beach-Destin, FL
8. Fairbanks-College, AK
9. Florence, SC
10. Gadsden, AL
11. Gainesville-Lake City, FL
12. Grand Junction, CO
13. Greenville-Washington, NC
14. Johnson City-Kingsport-Bristol, TN-VA
15. Middlesborough-Corbin, KY
16. Missoula, MT
17. Monroe-Ruston, LA
18. Montgomery-Selma, AL
19. Myrtle Beach-Conway, SC
20. North Port-Bradenton, FL
21. Palm Bay-Melbourne-Titusville, FL
22. Panama City-Panama City Beach, FL
23. Pocatello, ID
24. Prescott Valley-Prescott, AZ
25. Roanoke, VA

Source: American Lung Association 2025

 

What is Ozone Pollution?

Bad or ground-level ozone pollution is created when vehicle and other emissions mix with pollutants and are heated by the sun. Warmer weather increases ground-level ozone pollution.

What Makes Air Quality Unhealthy?

The Air Quality Index (AQI) grades air quality based on ground-level ozone, particle pollution, carbon monoxide, sulfur dioxide or nitrogen dioxide levels. Visit airnow.gov (Opens in a new window) or watch local alerts.

Protect Your Lungs from Ozone Pollution

  • Watch local air quality advisories.
  • Ozone levels are always lower in the morning, so plan outdoor activities accordingly.
  • The elderly, the very young and those with lung disease are at the highest risk from severe ozone pollution and should limit afternoon outdoor time during poor ozone days
  • Keep windows closed.
  • Take medications exactly as prescribed.
  • Use the circulate setting on your home thermostat to keep polluted air out.
  • Call your doctor if symptoms increase or if you need more medication.

Facemasks are highly encouraged to limit COVID-19 infection but provide no protection against ozone pollution.

 

More Information on Pollution



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