Minnesota water study

A new study of pharmaceuticals and other organic wastewater contaminants (OWCs) in Minnesota waters was recently published by the USGS (US Geological Survey). Samples were collected at 65 sites in Minnesota and included wastewater treatment plant influent and effluent, landfill leachate, feedlot lagoon leachate, surface water, ground water, drinking water intakes, and finished drinking water. The 72 OWCs detected out of a possible 92 analyzed represent a wide variety of sources. Samples generally included a mixture of compounds averaging 6 OWCs per sample, and 90 percent of the samples had at least one OWC.

Among all samples, 23 pharmaceutical compounds were detected, including human use prescription and non-prescription pharmaceuticals. Acetaminophen was among the three most frequently detected pharmaceutical compounds, along with caffeine and cotinine, a metabolite of nicotine. Trimethoprim, sulfamethoxazole, and an erythromycin metabolite were the most frequently detected antibiotics.

Twelve OWCs detected in the study are documented endocrine disruptors. Risks to humans and wildlife are not known. “Because they are a constant source, everyday aquatic organisms are bathed in these compounds, and I don’t think anybody knows how that affects them,” said Kathy Lee, chief author of the study, in a November 14th article in the Minneapolis Star Tribune. The Star Tribune article also quoted Rebecca Flood, environmental manager for the wastewater treatment plant in St. Paul, MN as saying “We’re not designed to remove these chemicals, and we’re not the source of them.” The full article may be accessed at USGS science for a changing world .

Prozac and painkillers found in Canadian tap water

An article by that title appeared in the November 13th, 2004 Vancouver Sun documenting the Canadian government’s first study of pharmaceuticals in drinking water. Researchers from the National Water Research Institute for Health and Environment Canada found nine different drugs in water samples taken from 20 drinking water treatment plants in southern Ontario.

According to the article, the following drugs were among nine found in detectable levels in Canadian drinking water: ibuprofen, naproxen, fluoxetine (Prozac), gemfibrozil, and carbamazepine. The government is confining its research to “acidic pharmaceuticals” that lend themselves to current analysis techniques. Jim Maguire, director of the institute’s aquatic ecosystem protection research branch, was quoted in the article as saying, "It’s kind of a brand new ball game and we don’t know enough. You need to know how long lasting [the contamination] is, and if it’s being continually reintroduced – but there’s no country in the world that has enough information. We’re kind of like where we were 25 years ago with PCBs and dioxides.”

Canada’s water quality experts have expressed concerns for some time. This study is the first official acknowledgement of those concerns.