On Monday, state-owned monitoring equipment detected “elevated” pollution levels in the air over the eastern half of the state.  Sean Fitzsimmons of the Iowa Department of Natural Resources says a “hurricane-like” low pressure system sort of sucked in polluted air from urban areas east of Iowa. 

“The area to our east, in the Chicago area, and the area to the southeast, toward the Ohio River Valley, is the most highly-polluted area in the nation and this low pressure system set up some winds that pulled those higher pollutant levels into the state,” he says. 

Department of Natural Resources monitoring sites in Clinton, Davenport, Muscatine, Iowa City and Waterloo recorded air pollution levels on Monday that exceeded federal standards.

“They were levels that folks like asthmatics, the elderly, people with respiratory and heart problems — they are levels that could cause those people issues if they were out doing a lot of physical exertion that increased their respiration rates,” Fitzsimmons says. 

January was the last time pollution levels that surpassed federal standards were reported over a broad area of the state.  According to Fitzsimmons, there’s a complicating factor in Iowa that causes air pollution in the winter.

“Here in Iowa there’s a bunch of extra ammonia because of hog lots and also other natural processes that can produce ammonia, and in the wintertime that ammonia can go into ammonium nitrate particles or at least when it gets colder — as it has been in these nights these days — you can get higher levels of ammonium nitrate in Iowa that you don’t see almost anywhere else because you have the extra ammonia,” Fitzsimmons says.  “And we saw really high values at nighttime during this period.” 

A storm system moved into the state yesterday and Fitzsimmons says it brought in “clean air” that swept the polluted air out of eastern Iowa by Tuesday night.