How does Peoria and Illinois rank when it comes to air quality?

Illinois’ air quality received mixed grades from the American Lung Association’s annual “State of the Air” report released last week.

While some counties in central and southern Illinois had low levels of pollution, areas in Chicagoland are some of the most polluted in the nation. The Chicago metropolitan area, according to the report, has the 17th highest level of ozone pollution of all cities in the nation.

Ozone is a product of vehicle exhaust and industrial pollution, and the pollutant can aggravate lung disease, increase the frequency of asthma attacks and make breathing difficult, according to the federal Environmental Protection Agency.

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The Chicago area was also ranked the 22nd most polluted city for year-round particle pollution, which results from construction, industrial waste, car exhaust and other sources.

“In the 25 years that the American Lung Association has been doing our ‘State of the Air’ report, we have seen incredible improvement in our nation’s air quality.” Kristina Hamilton, advocacy director at the ALA, said in a news release. “Unfortunately, more than 131 million people still live in places with unhealthy levels of air pollution, and Chicago is listed as one of the worst places for ozone and particle pollution, which disproportionately impacts low-income communities and communities of color.”

Downstate communities had generally cleaner air. While data on ozone pollution is only available for 23 Illinois counties, Adams, Effingham and Jo Daviess counties all received an “A” grade from the lung group for having zero days last year with high ozone pollution levels. For the 17 counties with data on particle pollution, seven received an “A” grade, including DuPage and McHenry counties in Chicagoland.

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Peoria County received a "B" grade for both ozone and particle pollution. Tazewell and Woodford counties did not report data.

The Springfield area’s air quality worsened this year compared to last year, when Sangamon County was ranked among the cleanest in the nation. It fell to a “C” grade for ozone and “B” grade for particle pollution, based on the number of days with high levels of each pollutant in the air.

Capitol News Illinois is a nonprofit, nonpartisan news service covering state government. It is distributed to hundreds of newspapers, radio and TV stations statewide. It is funded primarily by the Illinois Press Foundation and the Robert R. McCormick Foundation, along with major contributions from the Illinois Broadcasters Foundation and Southern Illinois Editorial Association.

This article originally appeared on Journal Star: Air quality rankings for Peoria and Illinois according to report