National state of the air report ranks America's most and least-polluted cities

KANSAS CITY, Mo. - Americans can now see which cities across the country have the cleanest air, and which are the most polluted.

The American Lung Association released its new " State of the Air" report Wednesday, giving cities grades based on the number of ozone alerts they had between 2008 and 2010, along with other factors. Data comes from state air quality monitors.

On the Kansas side, Johnson, Leavenworth, and Shawnee counties earned a ‘B' ranking. Sedwick and Sumner each scored lower with a ‘C.'

However some counties did better, including Linn, Trego, and Wyandotte. They each earned an ‘A.'

Meanwhile, on the Missouri side, only one county was clean enough in the skies to earn the top ranking. Monroe county scored the only ‘A,' with zero ozone alerts.

The worst scoring county in the state was St. Charles, with a total of 18 Orange Alert days during the three-year study period. That earned the county an ‘F' ranking, sharing the honor with Jefferson County, which experienced 10 Orange Alert days.

Clay County was given a ‘D', along with Clinton, Perry, and St. Louis counties.

Jackson County was not ranked. According to the study, there was no state air monitor present in that county during the period to keep track of the air quality.

Nationally, Ames-Boone, Iowa had the cleanest air in the study. Los Angeles was ranked as having the most polluted ozone of any city studied.

This is the 13th year the ALA has reported on the air pollution levels in America.

For more on the State of the Air report, visit

America's cleanest cities:

America's most-polluted cities:

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