Studies show trace pharmaceuticals in Montana water | Mar. 12, 2008

Though multiple studies show trace amounts of pharmaceuticals in some Montana water, activated charcoal drinking water filters and reverse osmosis systems are able to remove most of them, says the director of the Water Center at Montana State University.

Gretchen Rupp, director of the Montana University System Water Center, says that several studies have looked for and found common pharmaceuticals at specific sites in Montana. Among those studies showing trace pharmaceuticals are work in 2003 by the University of Montana that looked at septic system leachate at Frenchtown High School, work in 2005 by Montana government offices that found trace amounts in ground water in the Helena valley, including in some drinking water wells, work in 2007 that found traces in surface water below the Helena wastewater treatment site, and a 2007 statewide study by the Montana Bureau of Mining and Geology that showed trace amounts in some wells in agricultural and rural subdivision areas.

While some Montana samples documented no pharmaceutical contaminants, others showed enough to be active on animal systems, Rupp said. The mobility of any compounds in water is highly dependent on local soil and geological conditions.

"The problem is far from universal," she added.

Pharmaceutical compounds used by humans and in veterinary applications are not completely broken down within people or animals, so they can potentially be found in any waters influenced by human or animal waste. Such pharmaceuticals can be found in underground water, lakes and rivers. Septic and sewage treatment systems do not completely remove pharmaceutical compounds, and there are no water quality guidelines delineating safe levels in water.

Biologists have shown that trace amounts are unhealthy for creatures living in the water, like fish and amphibians. However, there has been little human research on pharmaceuticals at the minute quantities that have been detected, Rupp said.

Activated carbon filters and reverse osmosis units for drinking water are intended to remove trace amounts of contaminants, and can effectively remove pharmaceuticals.

"The problem is that most people who install a system never think of it again," Rupp said. "Filtration media have a limited life and must be changed periodically. Unless they are changed, they become ineffective at removing contamination and they become breeding grounds for microbes."

Unless treated by reverse osmosis, bottled water is not necessarily free of pharmaceutical compounds, she said.

Because the concentration of pharmaceuticals in water is extremely low, in the range of parts per trillion or less, few labs are qualified to test for them. The only laboratory in Montana that tests for pharmaceuticals in water is the Agricultural Experiment Station Analytical Laboratory at MSU-Bozeman, said Rupp.

Rupp suggested that Montanans who are concerned about their drinking water install treatment units at their kitchen taps or use counter-top activated carbon filters. However, she said she cannot vouch for those systems, and consumers should check with testing organizations or water quality specialists.

Sources: Montana State University. Mar. 12, 2008.