News Feature | November 19, 2014

Is Discharged Wastewater Tainting The Groundwater With Drugs?

Sara Jerome

By Sara Jerome,

A new study from the U.S. Geological Survey, a federal agency, investigated the threat of drugs released into the environment through wastewater.

The study found that treated municipal groundwater released back into the environment can sometimes result in groundwater carrying traces of pharmaceuticals and other contaminants.

Paul Bradley, the study’s lead author, explained the findings, noting the close connection between streams and groundwater.

 “Combined with the detection of pharmaceuticals in groundwater collected several meters away from the stream, these results demonstrate that addition of wastewater to this stream results in unintentional, directed transport of pharmaceuticals into shallow groundwater,” Bradley said in a statement from the agency.

The study focused on a small stream near Des Moines, IA.

"Samples for the study were taken from Fourmile Creek during the months of October and December of 2012. In October, the wastewater made up about 99 percent of the stream’s flow, whereas in December, the wastewater made up about 71 percent of the stream’s flow. During both months, Fourmile Creek experienced persistent dry conditions," Summit County Citizens Voice reported.

The findings?

"This study found that 48 and 61 different pharmaceuticals were present in the stream downstream of the wastewater discharge point during the two periods of study, with concentrations as high as 7,810 parts-per-trillion (specifically the chemical metformin, an anti-diabetic pharmaceutical)," USGS reported.

"Correspondingly, between 7 and 18 pharmaceuticals were present in groundwater at a distance of about 65 feet (20 meters) from the stream bank, with concentrations as high as 87 parts-per-trillion (specifically fexofenadine, an antihistamine pharmaceutical)," the agency said.

The research could have an impact on how bank filtration is used. "Bank filtration is the engineered movement of water between surface water bodies and wells located a short distance away on the streambank," USGS said.

A team of researchers at USGS is dedicated to tracking contaminants in U.S. waterways.

"They’ve found steroid hormones and the antibacterial agent triclosan in sewage; the antidepressant fluoxetine (Prozac) in fish; and compounds from both birth control pills and detergents in the thin, slimy layer that forms over stones in streams," the New York Times recently reported.

Check out Water Online's Drinking Water Contaminant Removal Solution Center.