WASHINGTON, (Reuters) - Six out of every 10 Americans - 186.1 million people - live in areas where air pollution endangers lives, according to the 10th annual American Lung Association State of the Air report released recently.

Some of the biggest sources of air pollution - dirty power plants, dirty diesel engines and ocean-going vessels - also worsen global warming, the Lung Association says in State of the Air 2009.
As America deals with the linked challenges of air pollution, global warming and energy, the Lung Association urges Congress, the U.S. EPA and individuals to choose solutions that help solve all three challenges together.
Nearly every major American city is still burdened by air pollution, and the air in many cities became dirtier since last year, the report finds, despite “substantial progress” made against air pollution in many areas of the country and more attention paid to the environment by America's growing green movement.
“This should be a wakeup call. We know that air pollution is a major threat to human health,” said Stephen 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.”
State of the Air 2009 includes a national air quality report card that assigns A-F grades to communities across the country and details trends for 900 counties over the past decade.
The report 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.
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.
“The more we learn, the more urgent it becomes for us to take decisive action to make our air healthier,” said Nolan.
Many cities, like Los Angeles, New York, Atlanta, Charlotte, Philadelphia, Washington, DC, and Baltimore have made improvements in their air quality over the past decade.
Only one city, Fargo, North Dakota, ranked among the cleanest in all three air pollution categories.
Seventeen cities appeared on two of the three lists of cleanest cities:
Billings, Montana; Bismarck and Sioux Falls, North Dakota; Cheyenne, Wyoming; Colorado Springs, Ft. Collins, and Pueblo, Colorado; Farmington and Santa Fe-Espanola, New Mexico; Honolulu, Hawaii; Lincoln, Nebraska; Midland-Odessa, Texas; Port St. Lucie, Florida; Redding, Salinas, and San Luis Obispo, California; and Tucson, Arizona.
The three cities most polluted by ozone are all in California - the Los Angeles-Long Beach-Riverside metropolitan area; Bakersfield, a center of agriculture, petroleum extraction and refining, and manufacturing in the San Joaquin Valley; and Visalia-Porterville, a San Joaquin Valley agricultural community.
Pittsburgh-New Castle, Pennsylvania tops the list of cities most polluted by 24 hour fine particle pollution, while the three California cities that top the most polluted ozone list are close behind in this category and also for year-round particle pollution.
----Ozone------
In March 2008, the U.S. Environmental Protection Agency adopted a new, tighter standard for ozone pollution. The new standard showed that unhealthy ozone levels are more widespread and more severe than previously recognized.
Evaluating the most recent data against the new standard, the American Lung Association found that approximately 175.4 million Americans - 58 percent - live in counties where ozone monitors recorded too many days with unhealthy ozone levels, far more than the 92.5 million identified in the State of the Air 2008 report.
Sixteen cities making this year's 25 most ozone-polluted list experienced worse smog problems than last year.
The Lung Association's review found consistent improvements in ozone in some cities, such as Los Angeles, with its long-standing ozone problem.
But two cities, Dallas-Ft. Worth and Las Vegas, have higher ozone levels than 10 years ago.
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,” said Charles Connor, American Lung Association president and chief executive. “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.”
In March 2008, the EPA adopted a standard of .075 parts per million, ppm, after legal action by the American Lung Association forced the agency to complete a formal review. This standard is not as strict as the standard of .060 ppm recommended by the Lung Association.
The association, along with states, public health and environmental groups, has taken the EPA back to court in an attempt to force the agency to adopt the .060 ppm standard before its scheduled five-year review in 2013.
----Particle pollution----
State of the Air 2009 grades counties for both 24-hour and year-round levels of particle pollution - 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,” the Lung Association says in its report, warning that “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 and Lancaster, Pennsylvania.
The annual average level of particle pollution worsened in a dozen cities, including Bakersfield and Los Angeles, California and Houston, Texas.
Roughly three 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.
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 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.”
Dr. Edelman suggests that people living in areas of high particle pollution “must recognize that this is the fact of their lives, and they must be more careful about other life factors - stop smoking, eat well, exercise.”
In addition, Dr. Edelman suggests, people who live with particle pollution “must take action help us and other organizations to change the EPA regulations. It's personal, it's affecting them and their neighbors.” In addition, he said, they can take local political action to change regulations such as engine idling, and clean up diesel-powered school buses.
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, the Lung Association points out. 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,” Connor said. “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.”