Research focus:
In the Pacific Northwest many marine and anadromous fish species utilize habitat for spawning or rearing adjacent to areas with intense human land use activities. Consequently, early life history stages (embryos and larvae) are potentially exposed to a vast array of chemical contaminants from urban and agricultural sources. We are utilizing zebrafish to begin to understand the impacts of common aquatic contaminants (e.g. pesticides, herbicides, metals, petroleum hydrocarbons) on fish development. Mechanistic insight gained from these studies will be translated into technologies for assessing thresholds of toxicity in local species of concern that are otherwise difficult to study in the lab (e.g. salmonids). These studies are aimed to address data gaps concerning the effects of anthropogenic contaminants on fish populations that are trust resources for NOAA Fisheries.

We focused initial studies on petroleum-derived polycyclic aromatic hydrocarbons (PAHs), ubiquitous contaminants associated with urbanization of the Puget Sound basin. Studies prompted by the Exxon Valdez oil spill in Prince William Sound, which contaminated spawning grounds for Pacific herring and pink salmon, identified a syndrome of edema, spinal curvature and craniofacial defects induced by exposure of embryos to complex PAH mixtures typical of weathered crude oil. We tested a series of model PAH compounds in zebrafish and found that individual 3-ring PAHs most abundant in crude oil are capable of inducing the syndrome, the primary etiology of which appears to be direct effects on cardiac function. PAH-induced cardiac dysfunction was associated with secondary consequences for late stages of cardiac morphogenesis, kidney development, neural tube structure, and the craniofacial skeleton. The impact of PAHs on the link between cardiac function and morphogenesis may contribute to the sublethal effects observed in wild fish species following oil spills. Overall, this experimental approach is an example of the emerging discipline of conservation medicine, or the application of biomedical research techniques to current problems in marine and freshwater conservation biology.

Biography:
B.S. Biology, Indiana University, 1988; Honors thesis in laboratory of Beth Raff

Ph.D. Genetics, Case Western Reserve University, 1995; laboratory of Terry Rosenberry (Department of Pharmacology)

M.D. Case Western Reserve University, 1996

Medical Teratology Fellow/Post-doc, University of Washington 1996-2001; Departments of Pediatrics and Biological Structure, laboratory of Henk Roelink.