Our air is getting better, but it's still not great, according to the The American Lung Association's 12th annual air quality report. And in Minnesota, it got a little worse in some metropolitan area counties.

Just over half of Americans -- 154.5 million people -- live in areas with levels of ozone and/or particle pollution that are often dangerous to breathe. And most of the problem areas are still in California.

Minnesota, smack dab in the wind-swept open spaces, fares pretty well in the report.

But particulate pollution, or soot, has increased in five Minnesota counties with a combined population of 1.3 million residents. That was somewhat offset by modest improvements in ozone pollution in two counties, and the city of Duluth was cited on two of three "cleanest cities" lists, recognizing the city's low ozone and year-round particulate pollution levels.

Ramsey County got the state's worst grade, a "D" for particulate pollution, down from a "C" last year. Also seeing declining scores for particulate pollution were Dakota, Olmsted, Scott and Stearns counties, which each earned a "C" this year after "B" grades in 2010. Other grades for particulate pollution were unchanged from last year's report.


"Progress the nation has made cleaning up coal-fired power plants, diesel emissions and other pollution sources has drastically cut dangerous pollution from the air we breathe,"said Charles D. Connor, American Lung Association President and CEO.

The report uses the most recent EPA data collected from 2007 through 2009 from official monitors for ozone and particle pollution, the two most widespread types of air pollution. Counties are graded for ozone, year-round particle pollution and short-term particle pollution levels. The report also uses EPA's calculations for year-round particle levels.
Nearly 60 million Americans (19.8 percent) live in counties with too many unhealthy spikes in particle pollution levels, and 18 million people live with unhealthy year-round levels of particle pollution. Particle levels can spike dangerously for hours to weeks on end (short-term) or remain at unhealthy levels on average every day (year-round).
"Particle pollution kills," said Norman H. Edelman, M.D., American Lung Association Chief Medical Officer. "When you breathe these microscopic particles, you are inhaling a noxious mix of chemicals, metals, acid aerosols, ash and soot that is emitted from smokestacks, tailpipes, and other sources.

that nearly half the people in the U.S. (48.2 percent) live in counties that received an "F" for air quality due to unhealthy ozone levels. Ozone (smog) is the most widespread air pollutant, created by the reaction of sunlight on emissions from vehicles, power plants and other sources.