Drugs in the water supply
LANSING – The emerging threat of pharmaceuticals, everyday chemicals and personal care products in drinking water may be the most difficult that water treatment plants have faced, experts say.
Lake Michigan takes 99 years to “turn over,” meaning chemicals that entered the lake a century ago may only just be exiting, according to the Alliance for the Great Lakes, which has offices in Grand Haven and Plymouth.
Its new report said that surface water in Lake Michigan contains six of 20 “priority” chemicals, or emerging contaminants identified by environmental engineers from Michigan State University.
They include flame retardants and a cholesterol-lowering drug.
After treatment, only a fire retardant remained in ready-to-drink water.
Experts said that membrane bioreactors may remove some pharmaceuticals while treating wastewater, but they cannot catch all the diverse medicines.
There are 35 treatment plants in the Great Lakes region that use such membrane technology: 14 on Lake Michigan, 13 on Lake Huron, five on Lake Superior, two on Lake Erie and one on Lake Ontario, according to Siemens Water Technologies, a company that constructs the membranes.
According to Tom Asmus, supervisor at the Marquette Area Wastewater Treatment Facility, the Marquette facility is not one of the five treatment plants on Lake Superior that uses membrane technology. He added that the compounds in Pharmaceutical and Personal Care Products, or PPCP, are not regulated, which means the treatment plant is not mandated or equipped to remove the compounds.
“It’s a fairly new issue, but one to take seriously,” Asmus said. “There is a vast use of these products being introduced into the water supply system with an inability to analyze incredibly small concentrations.”
Asmus said although they do not use the membrane technology, the process they do use achieves the same results. This process begins with treating roughly three million gallons of water per day. A gravity treatment is used under the large domes that can be seen from US-41. Under these domes, gravity inside the tanks are used to separate treated water from biomass. The tanks retain the biomass while the clean water is released back into the water systems. The biomass itself is ultimately treated and is referred to as biosolids, an organism or bacteria that consumes wastewater pollutants. The biosolids are released back into the land as fertilizer.
A membrane bioreactor plant in Traverse City was the largest in the nation when it opened in 2004. It serves 45,000 people in the city and surrounding area.
It took more than two and half years and about $31 million to upgrade an old plant deemed too small for the growing local population.
A forum for public comment identified two goals: use the existing plant in some way and exceed federal water requirements, said Scott Blair, the manager of the Traverse City wastewater treatment plant.
Pharmaceuticals in water have recently come under attention from scientists and government agencies like the Department of Environmental Quality.
It’s an emerging area of concern just beginning to be recognized, with many research projects going on at the federal level, said Richard Benzie of the community drinking water program at DEQ’s Office of Drinking Water and Municipal Assistance.
“Are we going to wait until it gets into the drinking water sources to deal with it, or start removing it in the waste streams?” he said.
Included in the pharmaceuticals group are personal care products, like cosmetics and suntan lotion, which also find their way into water sources, Benzie said.
“I admit, I’m probably contributing to the concentration of Lipitor in the environment,” he said.
DEQ reports that pharmaceuticals have been detected in ground water, lakes and streams. They can harm aquatic life, and scientists say damage to human health may become apparent in the future, or will become more likely as concentrations of medicine in the water increase, said the department’s deputy director, Jim Sygo.
Pharmaceuticals from human and animal waste end up in the water. And they get there when people flush unused medicines down the drain, something the Environmental protection Agency encouraged until the 1970s, according to Sygo.
Pharmaceuticals have already damaged wildlife in New York, where birth control pills were linked to male fish developing female characteristics and becoming sterile, according to the U.S. Geological Service.
In fact, some drugs may become more dangerous during conventional water treatment, according to a recent study led by Stuart Khan from University of New South Wales in Australia.
Preliminary findings suggest that the pharmaceuticals change due to an enzyme reaction or interaction with bacteria.
DEQ’s Benzie said that if the pharmaceuticals have an organic carbon base, then disinfection by chlorine could potentially create dangerous byproducts, but there is no definite evidence yet.
Even if small levels of dangerous compounds are created, it’s still up to the EPA to determine whether that danger outweighs changing the disinfecting process, which protects people from outbreaks of diseases like typhoid, Benzie said.
Asmus emphasized that the two main things area residents can do to combat PPCPs in the water systems is to participate in local medication collections instead of flushing pills down the toilets and to be as educated as possible on PPCPs and their affects on our water systems. He added that the Marquette area is still doing well, due to living next to such a large body of water.
“It’s still something to take seriously and continue to research,” Asmus said. “But as far as we know, it (PPCP) is not posing any public health issues.”
Every five years the EPA identifies up to 30 compounds that have no drinking water standards. Then, the agency requires a statistically significant number of public water systems to track the identified compounds, over five years. When the results are in, the EPA begins the task of determining if there’s a health risk.
Some studies say membrane bioreactors do a better job of removing medicines from water, Blair said.
A plant can’t determine which pharmaceuticals it removes. That kind of research fits better in academia, Blair said.