Only half of prescription drugs removed by sewage treatment – Drugs found in Lake Michigan, miles from sewage outfalls

By Brian Bienkowski and Environmental Health News
22 Novenber 2013 Only about half of the prescription drugs and other newly emerging contaminants in sewage are removed by treatment plants. That’s the finding of a new report by the International Joint Commission, a consortium of officials from the United States and Canada who study the Great Lakes. The impact of most of these “chemicals of emerging concern” on the health of people and aquatic life remains unclear. Nevertheless, the commission report concludes that better water treatment is needed. “The compounds show up in low levels – parts per billion or parts per trillion – but aquatic life and humans aren’t exposed to just one at a time, but a whole mix,” said Antonette Arvai, physical scientist at the International Joint Commission and the lead author of the study. “We need to find which of these chemicals might hurt us.” More than 1,400 wastewater treatment plants in the United States and Canada discharge 4.8 billion gallons of treated effluent into the Great Lakes basin every day, according to the study. The scientists reviewed 10 years of data from wastewater treatment plants worldwide to see how well they removed 42 compounds that are increasingly showing up in the Great Lakes. Six chemicals were detected frequently and had a low rate of removal in treated effluent: an herbicide, an anti-seizure drug, two antibiotic drugs, an antibacterial drug and an anti-inflammatory drug. Caffeine, acetaminophen and estriol (a natural estrogen) also were frequently detected in sewage but had high removal rates. The wastewater plants had a low removal rate (less than 25 percent chance of removing 75 percent or more) for 11 of the 42 chemicals. “The weight of evidence suggests that at least half of the 42 substances examined in the present study are likely to be removed in municipal wastewater treatment plants,” the authors wrote. [more]

Only Half of Drugs Removed by Sewage Treatment

By Brian Bienkowski
5 September 2013

(Environmental Health News) – Prescription drugs are contaminating Lake Michigan two miles from Milwaukee’s sewage outfalls, suggesting that the lake is not diluting the compounds as most researchers expected, according to new research. “In a body of water like the Great Lakes, you’d expect dilution would kick in and decrease concentrations, and that was not the case here,” said Dana Kolpin, a U.S. Geological Survey research hydrologist based in Iowa. It is not clear what, if any, effects the drugs are having on fish and other creatures in Lake Michigan. But this ability to travel and remain at relatively high concentrations means that aquatic life is exposed, so there could be “some serious near-shore impacts,” said Rebecca Klaper, an associate professor at the University of Wisconsin-Milwaukee and senior author of the study published in the journal Chemosphere. In addition, Milwaukee draws its drinking water from Lake Michigan, although no pharmaceuticals have been found in the city’s water, according to Milwaukee Water Works. The scientists tested effluent from two sewage outfalls and water and sediment from Lake Michigan (up to two miles from the outfalls) for 54 chemicals used in pharmaceuticals and personal care products. Twenty-seven chemicals were found in the lake, with four found most frequently: an antidiabetic drug called metformin, caffeine, the antibiotic sulfamethoxazole and triclosan, an antibacterial and antifungal compound found in some soaps, toothpastes and other consumer products. “Wastewater treatment plants are simply not designed to remove these chemicals,” Klaper said. “This tells us we shouldn’t assume that dilution solves the problem of putting these into the environment.” Metformin was detected at the highest levels – up to 840 parts per trillion one mile from the outfalls, and up to 160 parts per trillion two miles away. The researchers reported that 14 of the chemicals “were found to be of medium or high ecological risk,” and that the concentrations “indicate a significant threat to the health of the Great Lakes, particularly near shore organisms.” Of those, triclosan has been the most researched; it has proven acutely toxic to algae and can act as a hormone disruptor in fish. “You’re not going to see fish die-offs [from pharmaceuticals] but subtle changes in how the fish eat and socialize that can have a big impact down the road,” said Kolpin, who did not participate in the study. “With behavior changes and endocrine disruption, reproduction and survival problems may not rear their ugly head for generations.” Previous research has linked other pharmaceutical drugs in fish to slower reaction times to predators, altered eating habits and anxiety. There is a lot of research measuring pharmaceuticals in water, so “now we need to figure out what impact they may have,” Kolpin said. “The problem is the effluent and water don’t have one compound but a chemical mixture soup,” Kolpin said. “It’s going to be hard to tease out which of these compounds may do harm” to people or fish. [more]