Elevated pollution levels pushed environmental officials to issue an air quality advisory Monday, March 4, 2013 for the City of Muscatine, Iowa.
“Fine particulate and sulfur dioxide pollution levels in excess of the U.S. Environmental Protection Agency (EPA) health threshold were measured this morning in the city of Muscatine,” said a statement from the Iowa Department of Natural Resources.
The EPA’s 24-hour threshold for fine particles is 35 micrograms per cubic meter. Fine particulates averaged 57.5 microbrams per cubic meter at Garfield School in Muscatine on Monday.
Sulfur dioxide levels were also elevated at Garfield School, with the highest level at 158 parts per billion measured at 3 a.m. Monday. The standard is 75 parts per billion.
People living in the neighborhood of Garfield School who have respiratory or heart diseases, the elderly and children were cautioned to limit prolonged outdoor exertion until the air quality improves.
That was expected to happen Tuesday morning, when wind direction shifts as a winter storm passes through the area.
Fine particulates are emitted by vehicles and other combustion sources or they are formed by chemical reactions in the atmosphere. Sulfur dioxide emissions are usually caused by coal combustion at industrial sites.