How clean is the air you breathe? The nation's most polluted cities

Cities in California have the highest pollution levels, per annual report

Despite improvements in air quality, the annual State of Air report shows that 42% of U.S. residents still live in areas where pollution levels can make it dangerous to breathe.

For the 14th annual report, the American Lung Association (ALA) analyzed levels of ozone (commonly referred to as "smog") and particle pollution (often referred to as "soot" or "ash") using data that the Environmental Protection Agency (EPA) obtained at various official monitoring sites from 2009 to 2011.

They found that about 131.8 million of the nation's residents, or 42%, live in counties where the level of ozone, short-term particles, or year-round particles was unhealthful. Moreover, nearly 24.8 million residents—or 8% of the population—live in a county where all three pollution levels were unhealthful.

The most-polluted cities: California leads the pack

Most of the cities with the highest air pollution were located in California; however, cities like Dallas, PIttsburgh, and Cincinnati were also flagged for having unhealthy air.

According to the report, the most ozone-polluted cities in the United States are:

  • Los Angeles-Long Beach-Riverside, Calif.;
  • Visalia-Porterville, Calif.;
  • Bakersfield-Delano, Calif.;
  • Fresno-Madera, Calif.; and
  • Hanford-Corcoran, Calif.

Meanwhile, the cities most populated by short-term particle pollution are:

  • Bakersfield-Delano, Calif.;
  • Fresno-Madera, Calif.
  • Hanford-Corcoran, Calif.;
  • Los Angeles-Long Beach-Riverside, Calif.; and
  • Modesto, Calif.

The cities most populated by year-round particle pollution are:

  • Bakersfield-Delano, Calif.;
  • Merced, Calif.;
  • Fresno-Madera, Calif.;
  • Hanford-Corcoran, Calif.; and
  • Los Angeles-Long Beach-Riverside, Calif.

Overall air quality is improving

The report notes that 18 cities reported lower levels of long-term particle pollution, and 16 cities had the lowest levels ever recorded.

"We are happy to report that the state of our air is much cleaner today than when we started the 'State of the Air' report 14 years ago," says ALA President and CEO Harold Wimmer. But, he adds, "the work is not done, and the Environmental Protection Agency must continue the work necessary to achieve the promise of the Clean Air Act; healthy air that is safe for all to breathe."

Four cities made the report's list of the "cleanest cities" in America—more cities than in any previous report. To make the list, cities had to have no days with unhealthy ozone or particle pollution levels and be among the 25 cities with lowest long-term particle pollution levels. The four qualifying cities were:

  • Bismarck, N.D.;
  • Cape Carol-Fort Myers, Fla.;
  • Palm Bay-Melbourne-Titusville, Fla.; and
  • Rapid City, S.D.

Sources: ALA report, 4/24; ALA release, 4/24; ALA report methods, 4/24.

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