Take a deep breath, our air is cleanThe Duluth metro area ranks among the top metropolitan areas in the nation for cleanest air, according to the annual State of the Air Report released Wednesday by the American Lung Association.
By: John Myers, Duluth News Tribune
The Duluth metro area ranks among the top metropolitan areas in the nation for cleanest air, according to the annual State of the Air Report released Wednesday by the American Lung Association.
The city ranks with six others atop the list of cleanest cities for ozone pollution, with zero days of unhealthy ozone levels during the three-year period from 2009-11.
Duluth ranked 16th-best in the nation for annual particulate pollution.
Ozone pollution is created when nitrogen oxides and volatile organic compounds mix in the atmosphere, especially on hot, sunny days, said Kari Palmer, supervisor of the air data analysis unit of the Minnesota Pollution Control Agency. They can hang around and cause more problems if winds are calm.
Nitrogen oxides and VOCs also can come from traditional smokestack emissions, vehicle tailpipes and any combustion of wood, gas, coal or oil. And VOCs can come from evaporation of gasoline, paint or solvent fumes.
“It’s a problem caused when those emissions mix on hot, sunny days. And one of the reasons you may not have many of those is because you have fewer hot days,” Palmer said, noting natural sources can add to the mix.
Particulate matter is the fine pollution, such as sulfur dioxide, also created in combustion or from other chemicals such as ammonia used for fertilizer in farming.
The State of the Air Report is compiled with data collected by state agencies for the U.S. Environmental Protection Agency. As in past years, Minnesota’s scores in the report are mixed.
While Duluth got an A, Ramsey County (St. Paul) got a D for short-term particulate pollution, although that’s up from an F grade last year. Anoka and Washington counties in the Twin Cities, which had A grades last year for ozone pollution, slipped to a B in this latest report.
The Lung Association says the Twin Cities metro continues to sit on the list of top-50 “most polluted cities” for short-term particle pollution. But there is some improvement. The metro area went from 36th-most polluted in the nation last year to 42nd-worst this year.
Palmer credits the generally improving air quality to continued cleaner vehicle exhaust, thanks to federal regulations, and to major reductions in emissions from Minnesota power plants, especially coal-burning power plants, which have markedly reduced particulate and sulfur dioxide and nitrogen oxide emissions. Minnesota is getting more of its energy from wind and other renewable resources.
“In the Twin Cities and statewide, there has been real progress in reducing emissions — new wind and solar power projects, adding mass-transit capabilities to the Twin Cities, increased use of alternative fuels and advance vehicle technologies like E85, biodiesel and electric vehicles, decreased use of coal for energy production and increased controls on emissions sources,” Robert Moffitt, a spokesperson for the American Lung Association in Minnesota, said in announcing the rankings. “In many ways, we are on the right path to cleaner air but there is still much more to be done.”
Palmer said the American Lung Association data don’t yet include 2012, which saw record hot days across Minnesota and included more pollution advisories.
Rochester, Minn., was ranked 140th-most polluted in this year’s survey, slightly worse than the previous year’s 142. Palmer said geographic location can contribute to pollution problems, noting Rochester is more likely to be impacted by pollution drifting north from Chicago and St. Louis while Duluth isn’t.
Other cleanest-air cities include Bismarck, N.D., and Rapid City, S.D. On several of the top-10 lists for worst-polluted air were Bakersfield, Calif.; Los Angeles; Salt Lake City; and Pittsburgh.
More than 131 million people, 42 percent of the U.S. population, live in counties that have unhealthy levels of ozone or particle pollution. The lung association says people most susceptible to ozone and particulate pollution are infants, children, teenagers, seniors, people with lung diseases like asthma, people with heart disease or diabetes and anyone who works or exercises outdoors. The group says high levels of ozone or particle pollution can cause wheezing and coughing, asthma attacks, heart attacks and premature death.