Report: Chicago among US cities with ‘most polluted’ air. See the rankings.

CLEVELAND (WJW/NEXSTAR) — The American Lung Association has released its annual “State of the Air” report, and several major cities are among the worst in the nation for year-round particle pollution, also known as “soot.”

Each year for the past 26 years, the American Lung Association has analyzed data from official air quality monitors to compile the report and track unhealthy levels of ozone air pollution (smog) and particle pollution (soot). To determine particle pollution, PM2.5 (represented as µg/m3) is used, which is defined as fine particulate matter composed of particles 2.5 microns or smaller in diameter. 

The report then ranks the most polluted and cleanest U.S. cities based on an area’s number of unhealthy air days and the city’s particulate pollution.

This year’s report looked at a three-year period (2021-2023) and found Bakersfield-Delano in California to be the worst in the country for year-round particle pollution with 16.2 µg/m3. According to the report, Bakersfield-Delano was followed pretty closely by two other California cities for having the most polluted air, with Visalia and Fresno-Hanford-Corcoran ranking second and third.

The city with the “most dramatic” shift in the country was Cleveland, which finished 9th despite being ranked 54th just a year ago.

Three cities that are on the list for the first time include Kalamazoo, Michigan, and two Texas cities (Brownsville and Texarkana).

Here’s the American Lung Association’s full list of the 25 cities with the most year-round particle pollution:

1. Bakersfield-Delano, CA – 16.2 µg/m3
2. Visalia, CA – 15.7 µg/m3
3. Fresno-Hanford-Corcoran, CA – 14.8 µg/m3
4. Eugene-Springfield, OR – 14.4 µg/m3
5. Los Angeles-Long Beach, CA – 13.1 µg/m3
6. Detroit-Warren-Ann Arbor, MI – 13 µg/m3
7. San Jose-San Francisco-Oakland, CA – 13 µg/m3
8. Houston-Pasadena, TX – 12.5 µg/m3
9. Cleveland-Akron-Canton, OH – 12.3 µg/m3
10. Fairbanks-College, AK – 12.1 µg/m3
11. Indianapolis-Carmel-Muncie, IN – 11.9 µg/m3
12. Pittsburgh-Weirton-Steubenville, PA-OH-WV – 11.6 µg/m3
13. Chicago-Naperville, IL-IN-WI – 11.3 µg/m3
14. Cincinnati-Wilmington, OH-KY-IN – 11.2 µg/m3
15. Sacramento-Roseville, CA – 11.2 µg/m3
16. Brownsville-Harlingen-Raymondville, TX – 10.9 µg/m3
17. Medford-Grants Pass, OR – 10.5 µg/m3
18. Missoula, MT – 10.5 µg/m3
19. St. Louis-St. Charles-Farmington, MO-IL – 10.5 µg/m3
20. Kalamazoo-Battle Creek-Portage, MI – 10.4 µg/m3
21. Phoenix-Mesa, AZ – 10.4 µg/m3
22. Texarkana, TX-AR – 10.3 µg/m3
23. El Centro, CA – 10.2 µg/m3
24. Yakima, WA – 10.2 µg/m3
25. Spokane-Spokane Valley-Coeur d’Alene, WA-ID – 10.1 µg/m3

On the other end of the spectrum, Casper, Wyoming, finished as the U.S. city with the cleanest air, followed closely by two Hawaii cities (Honolulu and Kahului-Wailuku).

You can see the full “State of the Air” report here.

According to the Lung Association, ozone and particle pollution are the most widespread pollutants and among the “most dangerous.” The recent report found that nearly half of the U.S. population (46%) lives in an area that received a failing grade for at least one measure of air pollution.