Airport runway deicers impact on the environment greater than previously thought

The most widely used compound to remove dangerous ice from runways at many of the nation's airports may impact the environment more than previously realized. New research shows that potassium acetate may be harmful to aquatic life. This is the first published study of potassium acetate in airport runoff.

These findings follow a major shift in formulations used to deice airports across the country. During the 1990s, U.S. airports began using potassium acetate as a replacement for urea, a compound known to contribute toxic ammonia to nearby streams. Today, 67 percent of U.S. airports that apply deicers to runways use potassium acetate instead of urea.

Between 1996 and 2006, scientists from the U.S. Geological Survey (USGS) worked with Milwaukee's General Mitchell International Airport (GMIA) and collected water samples from streams at four sites near the airport. During this study, GMIA, like many other airports, began using potassium acetate to replace urea.

Forty percent of the samples collected following the change had concentrations of potassium acetate at levels high enough to be detrimental to aquatic life. (EPA standards have not been established for potassium acetate.) Concentrations of ammonia in forty-one percent of water samples collected from airport outfalls when urea-based deicers were in use had exceeded the Environmental Protection Agency's (EPA) water quality standards.

To read more, please see complete article at USGS Newsroom.