The American Lung Association released its semi-annual ''State of the Air'' report recently, ranking the cleanest and most polluted cities in the country. How did St. Louis fare? Predictably bad.
The particle pollution ranking is particularly scary. It basically tracks smog-- pollution caused by ash, soot, diesel exhaust, aerosols and other particulates. According to the Lung Association, breathing air with high particle pollution year round can, ''shorten life by one to three years.''
The good news for St. Louisans, however, is that study found the air quality in town has improved drastically over the past decade. This chart shows that the number of ''Unhealthy Ozone Days,'' in the city has halved since 1998.
For the first time in the study's history, a city outside of California (the steel city of Pittsburgh), earned the title of most polluted. Cheyenne, Wyoming supposedly has the freshest air.
To reach their conclusions, the group analyzed data from the U.S. Environmental Protection Agency from 2004-2006, calculating the average hourly amount of pollutants in the air in parts per million.