Many cities in the U.S. enjoy air that is considered clean for one or more of the pollution measures tracked in “State of the Air.” In this year’s report, 55 of the cities for which there is monitoring data had zero high short-term particle days and 75 cities had zero ozone days. Because year-round particle pollution is scored differently, the cleanest cities for this measure can be ranked, and the best 25 are considered cleanest.

In this year’s report, only five cities rank on all three cleanest cities lists for particle pollution and ozone. They had zero days high in particle pollution and in ozone and are among the 26 cities with the lowest year-round particle levels. After last year’s one-time appearance on all three cleanest lists, Asheville and Greenville, NC and Rochester NY all lost their place this year because of increases in ozone smog pollution. The other four again repeat their appearance on the combined list this year. Only Johnson City-Kingsport-Bristol, TN-VA, in its debut, was added to the list. 

Listed alphabetically, the cleanest cities are: 

  • Bangor, ME
  • Johnson City-Kingsport-Bristol, TN-VA
  • Lincoln-Beatrice, NE
  • Urban Honolulu, HI
  • Wilmington, NC

Did You Know?

  1. Nearly four in ten people in the U.S. live where the air they breathe earned an F in “State of the Air” 2024.
  2. More than 131 million people live in counties that received an F for either ozone or particle pollution in “State of the Air” 2024.
  3. Nearly 44 million people live in counties that got an F for all three air pollution measures in “State of the Air” 2024.
  4. Breathing ozone irritates the lungs, resulting in inflammation—as if your lungs had a bad sunburn.
  5. Breathing in particle pollution can increase the risk of lung cancer.
  6. Particle pollution can cause early death and heart attacks, strokes and emergency room visits.
  7. Particles in air pollution can be smaller than 1/30th the diameter of a human hair. When you inhale them, they are small enough to get past the body's natural defenses.
  8. Ozone and particle pollution are both linked to increased risk of premature birth and lower birth weight in newborns.
  9. If you live or work near a busy highway, traffic pollution may put you at greater risk of health harm.
  10. People who work or exercise outside face increased risk from the effects of air pollution.
  11. Millions of people are especially vulnerable to the effects of air pollution, including children, older adults and people with lung diseases such as asthma and COPD.
  12. People of color and people with lower incomes are disproportionately affected by air pollution that puts them at higher risk for illness.
  13. Air pollution is a serious health threat. It can trigger asthma attacks, harm lung development in children, and even be deadly.
  14. You can protect yourself by checking the air quality forecast in your community and avoiding exercising or working outdoors when unhealthy air is expected.
  15. Climate change enhances conditions for ozone pollution to form and makes it harder clean up communities where ozone levels are high.
  16. Climate change increases the risk of wildfires whose smoke spreads dangerous particle pollution.
  17. Policymakers at every level of government must take steps to clean the air their constituents breathe.
  18. The nation has the Clean Air Act to thank for decades of improvements in air quality. This landmark law has successfully driven pollution reduction for over 50 years.
  19. Particle pollution exposure from wildfire smoke harms health in ways that range from mild irritation to serious illness and premature death.
  20. Recent updates to the Air Quality Index give the public more accurate information about the health risk from air pollution, and when to take measures to protect themselves on bad air days.
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