Something In The Water

Baylor researchers find evidence of pharmaceuticals in fish near highly populated areas of U.S.

August 31, 2009

When Dr. Kevin Chambliss talks about the fillet of a fish, he doesn't just mean the part that is served with coleslaw and hush puppies.

Fish Pharma

Rather, Chambliss is referring to the edible part of a fish as well as the skin and the "belly flap" on the bottom of the creature. Those are the components of the fish that Chambliss and others on his team analyzed in a study to determine the levels of pharmaceuticals and personal care products (PPCPs) found in water bodies located near wastewater treatments plants at five locations across the country. The results of that study--released in March--generated media coverage in more than 250 publications worldwide. Stories ran in the Los Angeles Times, Chicago Tribune, Forbes and Newsweek and were featured on the national broadcasts of both CBS and ABC evening news shows. The story was also the highlighted front page feature on on March 25.

The study found low-level amounts of several PPCPs in the fish collected, including by-products of one pharmaceutical in wild fish that had not been previously seen. The findings were part of a pilot study by the United States Environmental Protection Agency (EPA) to look for PPCPs in fish found in water bodies across the country.

Chambliss, who along with Dr. Bryan Brooks was co-lead investigator of the study, says the media coverage wasn't surprising considering the publicity surrounding a previous, much smaller project.

The latest study looked at effluent-dominated sites--bodies of water located near wastewater treatment facilities--in Chicago, Dallas, Phoenix, Orlando, Fla., and West Chester, Pa., near Philadelphia.

Though the majority of the media coverage focused on Chambliss and Brooks, they are both quick to point out the work of others.

Bryan Brooks

"In the press, it was 'Brooks and Chambliss, Chambliss and Brooks,' says Brooks, associate professor of environmental sciences at Baylor. "Every paper that comes out [of the project] has students benefitting. They're publishing in peer-reviewed journals."

For example, former Baylor doctoral student Dr. Alejandro Ramirez, PhD '07, who is now the mass spectrometry specialist in the Baylor Sciences Building, was the lead author on the paper presenting the findings that garnered the recent national and worldwide media attention. That study will be published in a special issue of Environmental Toxicology and Chemistry that will focus on PPCPs in the environment. Former Baylor graduate students Laura Dobbins and Pilar Perez-Hurtado, who both graduated in May, are co-authors of that paper, a study which builds on previous research that Ramirez published in 2007 in Analytical Chemistry, "the leading analytical chemistry journal in the world," Brooks says.

This year's study has roots dating back to 2000, when Brooks collaborated with some researchers at the University of Mississippi pharmacy school and looked at various types of pharmaceuticals in water supplies.

"The work we started that looks at residues of drugs in fish really sprung from that," he says.

From there, he and Chambliss collaborated on a study on PPCPs found in Pecan Creek, a river segment downstream from the wastewater plant in Denton, just north of the Dallas-Fort Worth metroplex. The pair presented those findings at a 2003 conference in Seattle. Some members of the media dubbed the study "Fish on Prozac," and that got the attention of the EPA, which contracted with a private-sector firm called Tetra Tech to perform a similar study, but on a much larger scale. Chambliss, Brooks and their team, in turn, were contracted by Tetra Tech to use the methods developed in the Denton study for the bigger study.

"Tetra Tech put out an ad, saying, 'Here's the project.' We responded to that and were selected," Chambliss says. "We felt like this was targeted at us. We felt pretty certain there wasn't going to be another lab in the country that could compete with our proposal for addressing the needs of that project."

Fish Pharma Infograph

Once Baylor had secured the project, Tetra Tech collected the fish from the five locations as well as from the Gila River Wilderness Area in New Mexico.

"We picked the reference site in New Mexico to be one that would not have any human influence," Chambliss says. "It's like a control. There are no inputs into that stream from wastewater effluents. It's a completely natural water body."

Tetra Tech harvested sucker fish from New Mexico to act as the control group. The firm also collected largemouth bass from Illinois, carp from Arizona, bowfin from Florida, white sucker from Pennsylvania and small-mouth buffalo from Texas. Researchers from Baylor then dissected the fish, collecting the skin, meat and belly flap, as well as the liver.

"Then you need to get those in a homogenized form," Chambliss says. "So you take those tissues and grind them up, and at the end of the day they look like little pink milkshakes."

Eventually, the material was run through a process that separated it into basic components "and we detected whatever's coming out," Chambliss says. "We were able to get a larger group of compounds in one shot than previous methodologies," which made the Baylor research unique.

"While this study found the residue of several pharmaceuticals and personal care products in fish tissue, it also demonstrated for the first time that fish from several different locations across the country are exposed to multiple PPCPs in effluent-dominated waterways," Brooks said in a Baylor news release in March.

"There isn't a lot of data on the occurrence of PPCPs in fish tissue," says Denise Keehner with the U.S. EPA Office of Science and Technology. "A pilot study such as this is important to obtain data to begin to better understand the potential for human exposure to these compounds through this pathway (fish consumption) and to better understand what aquatic life such as fish are being exposed to.

"The results from pilot studies generally are important in making decisions about the need for more comprehensive studies. In this particular case, these results played a significant role in EPA's decision to pursue a broader effort to test fish at over 150 locations nationally."

While the EPA is planning to expand the testing, Chambliss says samples from 150 sites would be too much for the Baylor labs to handle.

"Some of your private-sector labs will develop the capability to do this, and they're much better equipped," he explains. "We're not a contract lab in academics. We wanted to be the first. Baylor can get credit for having done it first."

Chambliss says Baylor will not be involved with the EPA's next phase of fish study, though he would be open to working with the organization in the future.

"That this research occurred at Baylor just shows once again the quality of both our research and our faculty," says Dr. Truell W. Hyde, MS '80, PhD '88, physics professor and vice provost for research at Baylor. "This type of research routinely produces a larger impact due to public interest. This, in turn, brings Baylor researchers to the forefront, which is always good."

Like research often can, the results of this pilot study may have raised more issues than it solved, Chambliss says.

Researchers need to look at longer-term exposures to the products found in the fish, which can be done in a lab setting, he notes, "but it's very expensive and time-consuming."

The Baylor team's research also raises the question of whether certain chemicals need to be regulated.

"At this point, they're not regulated," Chambliss says. "Should they be? We need money to find out. The whole issue could go away if we improve wastewater treatment where it would remove all pharmaceuticals. Well, that's going to cost money and now it's not going to be just some federal research budget. That's taxpayers. Do we need to do it? We don't know. Nobody wants to pay the money just in case.

"While I'm willing to go on record and say there's probably not a human health effect we're going to see from this, what we've done is demonstrate that we've got to keep studying this. There are still questions that need to be answered."