Baylor Finds Medicine, PCPs in Fish from 5 Rivers

Baylor University researchers, working with the U.S. Environmental Protection Agency, have detected low-level residues of several human medications and personal care products in fish collected from effluent-dominated rivers, including the residue of one pharmaceutical in wild fish that has not been previously reported.

These findings, which were released March 23, are part of the first EPA pilot study designed to look for the occurrence of pharmaceuticals and personal care products (PPCPs) in fish from U.S. waterways.

“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,” said Bryan Brooks, Ph.D., associate professor of environmental sciences at Baylor and an aquatic toxicology expert on PPCPs who is a Baylor co-lead investigator on the study.

The study’s methodology was presented March 25 at the spring 2009 National Meeting of the American Chemical Society in Salt Lake City by Kevin Chambliss, Ph.D., a Baylor co-lead investigator with Brooks. The results also are scheduled to be published on-line in a special edition of Environmental Toxicology and Chemistry.

The study was funded by a contract from the EPA with Tetra Tech, a provider of consulting, engineering, and technical services. The Baylor University team, led by Chambliss and Brooks, was contracted by Tetra Tech to use their innovative PPCP detection methodologies in fish tissue to conduct the pilot study.

Many aquatic systems throughout the United States routinely receive effluent discharges from wastewater treatment plants. Sometimes, the flow of streams and rivers can become dominated by these effluents. Although there are federal standards for treated wastewater, no guidelines or federal testing standards exist for pharmaceuticals or most personal care products in wastewater because their effects in surface waters are not well understood. EPA undertook this pilot study as part of an overall strategy to better understand the occurrence of PPCPs in surface waters, sediment, and fish tissue.

The study involved collection of fish from five effluent-dominated rivers in various parts of the country. The sampling locations included discharge areas of wastewater treatment plants in Chicago, Dallas, Orlando, Fla.; Phoenix, and West Chester, Pa., near Philadelphia. The Gila River Wilderness Area in New Mexico provided a suitable reference site for the study, because it is isolated from human sources of pollution.

The Baylor researchers tested fish fillets and liver tissue for 24 different human medications. The researchers also tested fish fillets for 12 chemicals found in personal care products. The study results revealed that:

  • The residue of seven pharmaceuticals and two personal care products was present in fish at all five effluent-dominated river sites. In many cases, multiple compounds were found in the same fish.
  • For the first time, gemfibrozil, used to treat high cholesterol and triglyceride levels, was found in wild fish livers.
  • No pharmaceutical compounds or personal care product chemicals were detected in any fish collected at the reference stream in New Mexico.
  • Diphenhydramine, an over-the-counter antihistamine also commonly used as a sedative in non-prescription sleep aids and motion sickness; diltiazem, a drug for high blood pressure; carbamazepine, a treatment for epilepsy and bipolar disorder; norfluoxetine, the active metabolite of the antidepressant fluoxetine; and sertraline, an antidepressant, also were detected in this study, confirming results of previous projects by the Baylor researchers.
  • Galaxolide and tonalide, both fragrances used in soap and other personal care products, were found in fish fillet tissue from all five effluent-dominated river sites. The concentrations in the fish tissue for these fragrances were the highest of all compounds tested.

“We found the highest concentrations and frequencies of compounds in the fish livers but considering that the liver is the primary site of metabolism for xenobiotics in fish, as in humans, this result is logical.” said Chambliss, associate professor of chemistry and biochemistry at Baylor.

While the impact these compounds have on fish is not yet fully understood, it is documented in the scientific literature that antidepressant accumulation in fish may cause certain behavioral changes, which impact aggression, mating, and other behaviors necessary for fish survival.

Based on the pilot study findings, EPA is expanding its investigation of PPCPs in fish under its National Rivers and Streams Assessment. Fish collection began in 2008 and is continuing in 2009.