National air quality standards were exceeded 39 times in Iowa during 2011, a significant drop from the 85 exceedances recorded in 2010, according to the latest report from the Iowa Department of Natural Resources (IDNR).
All 39 exceedances last year were recorded in Muscatine - 37 for high SO2 (sulfur dioxide) levels and two for high PM 2.5 (particulate matter less than 2.5 microns).
In 2010, 33 air quality exceedances were recorded in Muscatine, 10 in Clinton and nine in Davenport.
A National Ambient Air Quality exceedance occurs when levels of an air pollutant - PM 2.5, ozone, sulfur dioxide, nitrogen oxide, lead, carbon monoxide or particulate matter 10 microns in diameter - reach a level which is "unhealthy for sensitive groups." Those sensitive groups include young children, people with respiratory conditions such as asthma and the elderly.
CLICK HERE to download a copy of the full Iowa exceedance report.
