Take a breath. How bad is Chicago's air quality?

Recent news has been saturated with images of American athletes, clad in surgical masks, arriving in Beijing prepared to compete in the 2008 Olympics despite the city's notorious poor air quality. The news isn't awful: at times, the city's air pollution has been as much as five times worse than it is this week.

The week of the opening ceremony, Beijing's air quality index (AQI) hovered around 80, or "moderate." By comparison, although there have been no "Air Pollution Action" days so far in 2008, Chicago's air quality sometimes straddles the line between "good" and "moderate."

In May, the Chicago metropolitan area had the distinction of appearing several times in the American Lung Association's State of the Air 2008, a yearly report that ranks the air in U.S. cities. Unfortunately, Chicago was on the "bad" lists. It was ranked 13th among the 25 U.S. cities most polluted by short-term particle pollution, and 24th among the 25 most ozone-polluted cities.

The two main types of air pollution, ozone and particle pollution can originate from the same sources, said Janice Nolen, assistant vice president for national policy and advocacy with the American Lung Association. Both are also equally widespread throughout the country.

Ozone is created when the volatile organic compounds produced by smokestacks and tailpipes cook in the atmosphere to eventually form a molecule with three oxygen atoms. It's very reactive, which makes it dangerous when it comes in contact with living tissue like human lungs.

Particles, on the other hand, are microscopic bits of soot and ash, and can also be formed chemically. "These particles are so small they're invisible to the eye and bypass the lung's defense mechanisms and get lodged in the lungs," Nolen said.

Although both cause health problems, particle pollution is generally more dangerous, according to Nolen. Breathing ozone-polluted air can cause coughing, wheezing and asthma attacks, she said. Particle pollution, however, has been found to kill people and cause heart attacks, strokes and lung cancer.

But are these merely the inevitable hazards that come with living in a major metropolitan area?

Yes and no, experts say.

"Transport of pollution is widespread," Nolen noted, citing high levels of ozone found in sparsely-populated areas such as the top of the Great Smoky Mountains. Some of the cities that were recognized as having the worst air quality in State of the Air were smaller cities that happen to have industries spewing out high levels of emissions, or areas in California that see a lot of wildfires.

Edward Doty, an environmental scientist with the Region 5 office of the EPA noted that Chicago is on a par with other large cities. "Any time you've got a large concentration of industry and public sources of emissions you're going to have the potential for a violation of these standards," he said.

And yes, according to Doty, Chicago is currently violating those standards. "It doesn't carry any penalties, but means we have to have an air quality plan and emissions controls," he said.

Poor air quality is especially dangerous for children and the elderly, as well as those with respiratory diseases, but it has the potential to affect everyone.

"I think we have a high population of patients with asthma, and the air pollution itself is a definite concern," said Dr. David You, a pulmonary and critical care doctor who treats patients at hospitals within the Adventist Midwest Health System.

Nolen suggested the best practice to avoid pollution-related complications is being aware of the day's air quality. The federal government has begun posting current air quality indexes and forecasts on airnow.gov, which allows everyone with Internet access to make decisions based on the day's air quality.

"It lets you know that you need to protect yourself," Nolen said. "If you've got pollution levels that are orange or higher, those are days that are particularly unhealthy." She suggests trying to stay indoors on unhealthy days, and definitely trying to limit outdoor exercise.

The City of Chicago is getting involved with the clean air movement as well. The Chicago Department of the Environment is a member of Partners for Clean Air, a coalition of Chicago businesses, government entities and non-profits that promote air quality improvements.

The Green Pays on Green Days program is one of the coalition's more original efforts. By visiting the Web site (greenpays.org) and pledging to do at least one thing to improve the air quality, participants are eligible to win environmentally-friendly prizes, awarded on each "green," or good, air quality day. This year's grand prize is a Toyota Prius.

As the Web site reminds us, there are ways that individual citizens can impact the region's air quality. "We don't have to settle for this air quality," Nolen said. "We can take steps to clean up the air." Riding public transit, not burning yard waste, conserving energy and not using gas-powered lawnmowers are several of the suggestions offered on the site.