Antibiotics, antidepressants, antihistamines, birth-control hormones…and the list goes on. Trace amounts of the drugs commonly ingested by Americans, but not fully absorbed by our bodies, are showing up in municipal water supplies.
Since an Associated Press investigation focused widespread attention on the problem last year, water utilities across the country are responding. So is the University of Colorado at Boulder, where a new laboratory was established in April 2008 by Professor Karl Linden and colleagues from the United States Geological Survey (USGS) who have been studying water quality for decades.
CU-Boulder's Center for Environmental Mass Spectrometry is providing new, highly accurate data on the presence of pharmaceuticals, hormones, and other organic contaminants in water, while also evaluating the effectiveness of methods for removing these compounds.
"Pharmaceuticals are biologically active compounds designed specifically to affect the human body," says Michael Thurman, a 30-year veteran of the USGS who helped found the center. "Low concentrations of parts-per-billion or parts-per-trillion generally aren't considered dangerous over the short term, but no one knows about the long-term human and ecological effects. There are troubling effects on wildlife, such as male fathead minnows that are becoming 'feminized' from traces of the human birth-control compound EE2 in streams at concentrations of parts-per-trillion."
Thurman and USGS Research Geologist Larry Barber, who together wrote a groundbreaking 2002 reconnaissance paper on contaminants in U.S. streams (the most-cited article in the history of the journal Environmental Science & Technology), will continue to collaborate through the new center. "The USGS is an interested partner with the university in studying this problem," Barber says.
"We also are fortunate to have support from industry in providing the increasingly sophisticated technology to do the analysis," says Imma Ferrer, chief analyst and one of the center's co-founders.
A liquid chromatograph/time-of-flight mass spectrometer on loan from Agilent Technologies, which offers better than two parts-per-million mass accuracy, is the center's work horse. Operated by Ferrer, the system allows researchers to determine the elemental formula of an unknown substance by conducting a forensic-style investigation that will help determine where utilities should spend their engineering dollars.
The lab is currently working with water utilities in four states, including Colorado, to determine the specific pharmaceuticals that are not being removed by municipal treatment plants. Water samples from each area are analyzed for their component parts, which are then compared to libraries of pharmaceuticals, pesticides, and other emerging contaminants such as endocrine disruptors, for identification.
The process can be time-consuming and expensive, so it's important that the researchers base their analysis on contaminants with a high probability of being present, Thurman says.
Twenty to thirty years ago, research focused on determining whether pesticides and other hazardous chemicals derived from nonpoint sources such as agriculture were present in our lakes and streams. Now researchers are looking at the presence of organic wastewater point-source contaminants and the impact of increasing population adjacent to the country's water resources.
The public hasn't always been particularly conscious of water quality concerns. Barber's 1996 USGS study reporting traces of caffeine found in the Mississippi River, for example, resulted in news accounts that made it into a joke, he says. And some water quality data released in the 1980s were largely ignored because the public wasn't knowledgeable about the contaminants that were found.
Today, the public is much more concerned about drinking water quality. As a result of the media attention to the presence of pharmaceuticals in drinking water, people now are asking what they can do to help keep such contaminants out of their water systems—for example, not disposing of unused pills by dumping them down a drain—and many pharmacies have instituted drug take-back programs, Barber says.
The fact that many municipal water treatment plants haven't upgraded equipment that was constructed in the 1970s and 1980s is a continuing challenge though.
"Basic water-treatment technology, both for wastewater and for drinking water, has changed in recent years, now including options such as treatment by ozone, UV, and activated carbon," says Linden. "We're looking at the problem from a number of angles—first, to help define this growing problem and to investigate the need for more testing and treatment at the municipal level. We also intend to work with people around the world to help find cost-effective solutions by evaluating various water-treatment options."
Assistant Professor Fernando Rosario-Ortiz recently joined the center as an expert in chemical oxidation processes for treating these chemicals in water.
While the center's experts emphasize that the health effects of trace pharmaceuticals in drinking water are still unknown, they say they are likely minimal while the effects on ecosystems could be more serious.
"Water is the new oil," Linden says. "Water is going to be a very valuable commodity and we need to put effort into making sure it's safe and desirable for the general public."