California Cities With The Cleanest & Dirtiest Air

According to the World Health Organization, 99% of the world's population breathes poor-quality air. Over time, inhaling this air can cause cardiovascular and respiratory disease. Thanks to things like busy highways and smoke from wildfires, American cities have a big problem with air pollution.

The American Lung Association tracks air pollution across the U.S. and found the cities with the cleanest and dirtiest air. According to KTLA, their annual report uses data from the Environmental Protection Agency on the presence of two types of pollutants: ozone (smog) and particulate matter, which comes from manmade sources like transportation, power plants, and natural sources like desert dust.

According to their report, California takes up seven of 10 spots in the most polluted cities. These are the California cities with the highest amount of ozone pollution:

1. Los Angeles-Long Beach
2. Bakersfield
3. Visalia
4. Fresno-Madera-Hanford
5. Sacramento-Roseville
6. San Diego-Chula Vista-Carlsbad
7. San Jose-San Francisco-Oakland
8. El Centro
9. Chico
10. Redding-Red Bluff

And these are the California cities with the worst year-round particle pollution:

1. Bakersfield
2. Fresno-Madera-Hanford
3. Visalia
4. Los Angeles-Long Beach
5. San Jose-San Francisco-Oakland
6. El Centro
7. Sacramento-Roseville
8. Redding-Red Bluff

These are the U.S. cities with the cleanest air:

1. Urban Honolulu, Hawaii
2. Kahului-Wailuku-Lahaina, Hawaii
3. Cheyenne, Wyoming
4. Wilmington, North Carolina
5. Casper, Wyoming
6. St. George, Utah
7. Bellingham, Washington
8. Elmira-Corning, New York
9. Sioux Falls, South Dakota
10. Duluth, Minnesota/Wisconsin