Pharmaceuticals present in Burlington wastewater

Water discharged from Burlington's wastewater treatment plant into Lake Champlain contains concentrations of pharmaceuticals high enough to reflect demographic shifts in the city, according to a University of Vermont researcher.

Lake Champlain is the source of drinking water for tens of thousands of people in the Burlington area. Scientists say the risk to human health from drugs in the water appears to be low, but more research is needed, especially in regards to the effects long-term exposure could have on vulnerable populations like pregnant women, children and people with allergies.

Drug residue has had a notable impact on aquatic life in other bodies of water, with pharmaceutical buildup seen in the brains of fish and behavior changes observed in zooplankton, which could have a cascading effect through the food chain. Research on the effects in Lake Champlain specifically has not yet taken place.

Christine Vatovec, an environmental science research professor at UVM, sampled water leaving the Burlington treatment plant for 10 days in May 2014 as college students left town. She could see a difference in the mix of drugs as the days went on. She saw antivirals in the water go down and ulcer medication go up. She saw a spike of antihistamines that correlated to a rise in pollen count.

Medications get into the water in three ways, Vatovec said. People flush extra pills down the toilet; drugs that are rubbed onto the skin are washed off into shower drains; and the body excretes medicine that isn't absorbed.

"Wherever there's people peeing, basically, there's going to be pharmaceuticals in the water," she said.

Pharmaceuticals in the water are a nationwide-problem, Vatovec said. A study by the U.S. Geological Survey, published in 2002, found medications in 80 percent of streams sampled across the country. A 2014 study by the federal Environmental Protection Agency sampled the output of 50 large treatment plants and found drugs in all of them.

The Burlington plant was built more than 100 years ago when the primary concern was filtering out solids like feces, not chemicals like residue from antidepressants and antibiotics, she said.

The best way to get pharmaceuticals out of the water would be to install a reverse osmosis system, Vatovec said. Those systems are extremely expensive.

"It's not yet been considered something necessary," she said.

Patrick Phillips, a hydrologist with the U.S. Geological Survey who collaborated with Vatovec on the project, said the water from the plant is so diluted by the lake that the overall concentrations of pharmaceuticals are very low.

"The amount of water you'd have to drink to get a therapeutic dose would be quite high," he said.

Steve Roy, the interim assistant director of water resources for Burlington, estimated there are 6.8 trillion gallons of water in Lake Champlain. Only about 6.8 gallons of contaminants need to be in the lake for scientists to detect them.

A 2011 World Health Organization report concluded most concentrations of pharmaceuticals were too low to cause healthy humans harm, but raised concerns about the effects drug residue-tainted water might have on pregnant women, children and other sensitive populations. In addition, the report recommended that if higher concentrations were suspected, monitoring and screening should take place.

"We are just getting to the point where enough research has been done to convince most researchers that risks to humans from pharmaceuticals in drinking water are low," said Mitch Kostich, the EPA scientist who authored the 2014 study. "Nevertheless, it is impossible to prove a negative, and some researchers, as well as some members of the public, would like to see a more thorough search for potential effects before being convinced."

Current state and federal regulation do not require testing for pharmaceuticals in drinking water.

Testing is complicated, time-consuming and costs money, Roy said.

James Ehlers, executive director of Lake Champlain International, called pharmaceuticals in the water an ongoing issue.

"Our long-term concern is the repeated exposure," he said. He'd also like to see some tests for pharmaceuticals in the drinking water coming out of Lake Champlain.

Correction: This article originally misidentified the body of water where drug residue has impacted aquatic life. 

Contact Jess Aloe at 802-660-1874 or jaloe@freepressmedia.com. Follow her on Twitter at www.twitter.com/jess_aloe