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Chemicals in shampoo, toothpaste, and medicines are being detected in surface waters and fish nationwide, fueling suspicion that some pharmaceuticals and personal care products are causing ecological harm.
But research on the subject is limited; few facts are known about actual effects on aquatic life. University of Washington researchers, working on a study funded by the Washington State Department of Ecology, are investigating the presence and effects of these chemicals in south Puget Sound.
"State and federal agencies are under pressure to identify specific compounds among thousands that may pose ecological risk. It’s a formidable task," said Professor Evan Gallagher, who leads the study.
Over the next two years, his team will analyze 126 drugs and personal care products in fish and water samples, and study links between the chemicals and adverse effects in two species: juvenile Chinook salmon and Pacific staghorn sculpin.
The researchers are developing molecular, biochemical, and physiological indicators—biomarkers—to identify which species and sites may be at risk.
To test the variables, the researchers are comparing fish and water in estuaries downstream of wastewater treatment plants with fish and water farther away. They will also validate the biomarkers they find in the field-sampled fish with lab studies under more controlled conditions than conditions encountered by fish in the field.
In his 30-year career, Gallagher has investigated waterway pollutants, such as copper from automotive brake pads and flame retardants from furniture, and identified biological markers of injury that link exposure to fish fitness and survival. He has developed molecular and biochemical biomarkers that can detect the adverse effects of chemicals that originate from wastewater treatment plants and agricultural and industrial sources.
In a lab setting, a particular compound can adversely affect fish—for instance, in terms of growth or reproduction. In the environment, however, the exposure to that compound might be a thousand or a million times less, explained Gallagher. The compound’s mere presence may be less detrimental, if it is a detriment at all, to the animal’s health.
"We have to look carefully at the level of exposures that the fish are receiving, and then determine if those exposures are causing subtle effects that affect the animals physiology," Gallagher said.
He is working with Andrew Yeh, a PhD student in our department and a member of the Gallagher laboratory. Yeh is playing a critical role in co-managing the logistical complexities of the project as well as developing innovative biomarkers of cell function as part of his dissertation. Other members of the team include Graham Young, professor of aquatic and fishery sciences; and James Meador, a research ecotoxicologist with the Northwest Fisheries Science Center.