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60 Percent Of Americans Live In Areas Where Air Is Dirty Enough To Endanger Lives

April 30, 2009
American Lung Association
Six out of ten Americans -- 186.1 million people -- live in areas where air pollution levels endanger lives, according to a new report listing cities with high and low pollution levels. Nearly every major U.S. city is still burdened by significant amounts of air pollution.

The 10th annual American Lung Association State of the Air report released April 29 finds that six out of ten Americans--186.1 million people -- live in areas where air pollution levels endanger lives. 

State of the Air 2009 acknowledges substantial progress against air pollution in many areas of the country, but finds nearly every major city still burdened by air pollution. Despite America’s growing “green” movement, the air in many cities became dirtier. The State of the Air report includes a national air quality “report card” that assigns A-F grades to communities across the country. The report also ranks cities and counties most affected by the three most widespread types of pollution (ozone—or smog, annual particle pollution, and 24-hour particle pollution levels) and details trends for 900 counties over the past decade.

“This should be a wake-up call.  We know that air pollution is a major threat to human health,” said Stephen J. Nolan, American Lung Association National Board Chair. “When 60 percent of Americans are left breathing air dirty enough to send people to the emergency room, to shape how kids’ lungs develop, and to kill, air pollution remains a serious problem.”

The report finds that air pollution hovers at unhealthy levels in almost every major city, threatening people’s ability to breathe and placing lives at risk. Some of the biggest sources of air pollution, including dirty power plants, dirty diesel engines and ocean-going vessels, also worsen global warming.

“The more we learn, the more urgent it becomes for us to take decisive action to make our air healthier,” added Nolan.

Many cities, like Los Angeles, New York, Atlanta, Charlotte, Philadelphia, Washington, D.C., and Baltimore have made considerable improvements in their air quality over the past decade. People living in some of these cities however, are breathing even dirtier air than what was reported in the Lung Association’s 2008 report. Only one city—Fargo, N.D.—ranked among the cleanest in all three air pollution categories covered in State of the Air.


Sixteen cities making this year’s 25 most ozone-polluted list experienced worsened ozone (smog) problems than last year’s report found. Fifty-eight percent of people in the United States live in counties with recorded unhealthy levels of ozone air pollution, measured against the tighter standard in effect since March 2008. The new standard showed that unhealthy ozone levels are more widespread and more severe than previously recognized.

The report’s review of the past 10 years identified consistent improvements in ozone in some cities, most notably Los Angeles, which has long been recognized for its serious ozone problem. By contrast, two cities, Dallas-Ft. Worth and Las Vegas, have higher ozone levels than 10 years ago. The report reviewed all previous data against the new EPA standard to appropriately trace the trends.

Ozone is the most widespread form of air pollution. When inhaled, ozone irritates the lungs, resulting in something like a bad sunburn. The health effects of breathing ozone pollution can be immediate. Ozone can cause wheezing, coughing and asthma attacks. Breathing ozone pollution can even shorten lives.

“More than 175 million Americans live in areas with unhealthy smog levels—that’s 80 million more than we identified in last year’s report,” explained Charles D. Connor,  American Lung Association President and CEO. “We at the American Lung Association believe that the new ozone standard is not yet strong enough to protect human health—an opinion nearly all scientific experts share.”

Particle Pollution

State of the Air grades counties for both 24-hour and year-round particle pollution levels. Particle pollution is a toxic mix of microscopic soot, diesel exhaust, chemicals, metals and aerosols. It is the most dangerous and deadly of the outdoor air pollutants that are widespread in America. Breathing in particle pollution can increase the risk of early death, heart attacks, strokes and emergency room visits for asthma and cardiovascular disease.

One in six people in the United States lives in an area with unhealthy year-round levels of fine particle pollution (termed annual average levels). Nine cities in the list of the 25 most polluted by year-round particle pollution showed measurable improvement, including five cities that reported their best year-round levels since the Lung Association began tracking this pollutant: Pittsburgh, Cincinnati, Atlanta, York, Pa., and Lancaster, Pa. The annual average level of particle pollution worsened in a dozen cities, including Bakersfield, Calif., Los Angeles and Houston.

Roughly 3 in 10 Americans live in counties with unhealthful spikes of particle pollution which can last from hours to days (termed 24-hour levels). Thirteen cities had more days—or more severe days—of spikes than in last year’s report. Eleven cities have improved continually since the 2007 report.

Emerging research has redefined the severity and immediate health impacts of particle pollution and ozone, as well as an expanded definition of specific groups at great risk. New data show that women in their 50’s may be particularly threatened by air pollution and that diesel truck drivers and dockworkers who are forced to breathe exhaust on the job may face a greater risk of developing lung cancer or chronic obstructive pulmonary disease. California researchers have tripled their estimate of the number of people that particle pollution kills each year in their state.

“The science is rock-solid. We now know that air pollution can impair the lung function of even the healthiest people,” said Norman H. Edelman, MD, American Lung Association Chief Medical Officer. “Air pollution worsens asthma and is a direct cause of heart attacks, which makes people living with lung and heart disease especially vulnerable.”

Low income people and some racial and ethnic groups often face greater risk from pollutants. Pollution sources like factories and power plants may be closer to their homes. Many live near areas with heavy highway traffic or have poor access to health care, which makes them even more vulnerable. Some racial and ethnic groups have a higher prevalence of diseases like asthma or diabetes, which compounds the ill effects of air pollution for these groups.

“We need to renew our commitment to providing healthy air for all our citizens—a commitment the United States made almost 40 years ago when Congress passed the Clean Air Act,” Connor said. “After four decades, we still have much work to do. America needs to cut emissions from big polluters like coal-fired power plants and ocean-going vessels. We need to fix old dirty diesel engines to make them cleaner and strengthen the ozone standards to better protect our health. We also need to improve the decaying infrastructure of air monitors. America must now enforce the laws that help us improve our nation’s air quality.”

As America faces the challenges of air pollution, global warming and energy, the American Lung Association urges Congress, the EPA and individuals to choose solutions that help solve all three challenges together. Some steps that sound like good solutions for one problem can make air pollution worse.

Americans can make personal changes to improve air quality immediately and ultimately impact climate change as well: drive less; don’t burn wood or trash; use less electricity; and make sure local school systems require clean school buses.

Cleanest Cities In USA

Cleanest U.S. Cities for Short-term Particle Pollution (24 Hour PM2.5)

*Cities below had equal scores.

  • Alexandria, La.
  • Amarillo, Texas
  • Austin-Round Rock, Texas
  • Bismarck, N.D.
  • Brownsville-Harlingen-Raymondville, Texas
  • Cheyenne, Wyo.
  • Colorado Springs, Colo.
  • Corpus Christi-Kingsville, Texas
  • Fargo-Wahpeton, N.D.-Minn.
  • Farmington, N.M.
  • Fort Collins-Loveland, Colo.
  • Grand Junction, Colo.
  • Longview-Marshall, Texas
  • Midland-Odessa, Texas
  • Oklahoma City-Shawnee, Okla.
  • Portland-Lewiston-South Portland, Maine
  • Pueblo, Colo.
  • Redding, Calif.
  • Salinas, Calif.
  • San Luis Obispo-Paso Robles, Calif.
  • Santa Barbara-Santa Maria-Goleta, Calif.
  • Santa Fe-Espanola, N.M.
  • Sioux Falls, S.D.
  • Tucson, Ariz. 

10 Cleanest U.S. Cities for Long-term Particle Pollution (Annual PM2.5)

*Cities listed in rank order. Duplicate position numbers indicate ties.

1. Cheyenne, Wyo.

2. Santa Fe-Espanola, N.M.

3. Honolulu, Hawaii

4. Great Falls, Mont.

5. Flagstaff, Ariz.

6. Farmington, N.M.

7. Anchorage, Alaska

8. Tucson, Ariz.

9. Bismarck, N.D.

9. Salinas, Calif.

Cleanest U.S. Cities for Ozone Air Pollution

*Cities below had equal scores.

  • Billings, Mont.
  • Carson City, Nev.
  • Coeur D’Alene, Idaho
  • Fargo-Wahpeton, N.D.-Minn.
  • Honolulu, Hawaii
  • Laredo, Texas
  • Lincoln, Neb.
  • Port St. Lucie-Sebastian-Vero Beach, Fla.
  • Sioux Falls, S.D.

Most Polluted Cities in USA

10 U.S. Cities Most Polluted by Short-term Particle Pollution (24 Hour PM2.5)

*Cities listed in rank order. Duplicate position numbers indicate ties.

1. Pittsburgh-New Castle, Pa.

2. Fresno-Madera, Calif.

3. Bakersfield, Calif.

4. Los Angeles-Long Beach-Riverside, Calif.

5. Birmingham-Hoover-Cullman, Ala.

6. Salt Lake City-Ogden-Clearfield, Utah

7. Sacramento-Arden-Arcade-Yuba City, Calif.-Nev.

8. Logan, Utah

9. Chicago-Naperville-Michigan City, Ill.-Ind.-Wis.

9. Detroit-Warren-Flint, Mich.

U.S. Cities Most Polluted by Year-Round Particle Pollution (Annual PM2.5)

*Cities listed in rank order.

1. Bakersfield, Calif.

2. Pittsburgh-New Castle, Pa.

3. Los Angeles-Long Beach-Riverside, Calif.

4. Visalia-Porterville, Calif.

5. Birmingham-Hoover-Cullman, Ala.

6. Hanford-Corcoran, Calif.

7. Fresno-Madera, Calif.

8. Cincinnati-Middletown-Wilmington, Ohio-Ky.-Ind.

9. Detroit-Warren-Flint, Mich.

10. Cleveland-Akron-Elyria, Ohio 

U.S. Cities Most Polluted by Ozone

*Cities listed in rank order.

1. Los Angeles-Long Beach-Riverside, Calif.

2. Bakersfield, Calif.

3. Visalia-Porterville, Calif.

4. Fresno-Madera, Calif.

5. Houston-Baytown-Huntsville, Texas

6. Sacramento-Arden-Arcade-Yuba City, Calif.-Nev.

7. Dallas-Fort Worth, Texas

8. Charlotte-Gastonia-Salisbury, N.C.-S.C.

9. Phoenix-Mesa-Scottsdale, Ariz.

10. El Centro, Calif.

The full State of the Air report can be found at

Story Source:

Materials provided by American Lung Association. Note: Content may be edited for style and length.

Cite This Page:

American Lung Association. "60 Percent Of Americans Live In Areas Where Air Is Dirty Enough To Endanger Lives." ScienceDaily. ScienceDaily, 30 April 2009. <>.
American Lung Association. (2009, April 30). 60 Percent Of Americans Live In Areas Where Air Is Dirty Enough To Endanger Lives. ScienceDaily. Retrieved May 21, 2024 from
American Lung Association. "60 Percent Of Americans Live In Areas Where Air Is Dirty Enough To Endanger Lives." ScienceDaily. (accessed May 21, 2024).

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