Air Alert Issued Today; Air Quality Unhealthy Yesterday

DES MOINES – Air quality is predicted to reach unhealthy conditions today across much of eastern Iowa due to particulate air pollution, state officials said today. Air quality yesterday was also unhealthy across much of the state, measuring 103 to 124 on the national Air Quality Index.

“Asthmatics, children and healthy adults planning extended outdoor exertion or vigorous activity today may wish to reconsider and wait for better air quality to return,” said Brian Button, DNR air information specialist. Persons with other respiratory diseases and heart disease are also advised to reduce prolonged, vigorous outdoor activity.

Currently levels in Scott County are elevated from yesterday’s levels, and could push above 150 on the AQI. If these levels persist today, sensitive groups should avoid all prolonged outdoor activity and everyone else should reduce strenuous outdoor activity.

“It isn’t a healthy day to be running, cycling or other intensive outdoor activities,” said Button.

Levels yesterday were highest in Scott County measuring 123 on the AQI. Clinton and Polk Counties measured 115 and 103 and a monitor in the Montgomery County in southwestern Iowa measured 104. Surrounding counties likely had similar levels. Linn County air quality was moderate yesterday, as was air quality in north central and northwest Iowa.

The Air Quality Index (AQI) reports pollution levels using a color-coded and numerical range for pollutants. The higher the AQI, the poorer the air quality. An AQI of 1 to 50 is green or good, 51 to 100 is yellow or moderate, 101 to 150 is orange or unhealthy for sensitive groups, 151 to 200 is red, unhealthy for everyone. Rarely monitored in the nation are purple for very unhealthy (201 to 300) and maroon for hazardous (301 to 500.) Air quality in Iowa rates good to moderate on the vast majority of days, with several days of unhealthy air monitored annually.

Particulate matter is a generic term to describe microscopic sized solids and aerosols in the air. Because the particles are so small they are able to penetrate the deepest parts of the lungs, increasing the likelihood of symptoms in sensitive individuals, including children, the elderly and those with heart and respiratory disease.

Thermal inversions may be contributing to the unhealthy air. Inversions occur when cold air close to the ground is trapped by a layer of warmer air above that acts as a lid, trapping particulate and gas emissions from tailpipes, burning and industries. Hazy skies are often associated with higher particulate levels, which scatter light in the atmosphere. Airborne emissions can also react to form particulate pollution as well.

Iowans can view current particulate pollution levels online at www.epa.gov/airnow. Online data also includes ozone smog levels in the summer months as well.

For more information contact Brian Button at 515-281-7832 or by email at brian.button@dnr.iowa.gov.