Distribution and Degradation of the Antidiabetic Drug, Metformin, and its Breakdown Product, Guanylurea, in the Columbia River Basin (2016-18)

Tawnya Peterson
Institute of Environmental Health
Oregon Health & Science University
3181 SW Sam Jackson Park Rd, HRC-3
Portland, OR 97239
Phone: 503-346-3423

Co-PI: Joseph Needoba, OHSU

Metformin is a widely prescribed antidiabetic pharmaceutical present at relatively high concentrations compared to many other trace pollutants, including chemicals of emerging concern (CEC), in water bodies worldwide. Metformin has recently been shown to have endocrine disrupting effects in fish, making it a potentially important environmental concern. Dr. Peterson and her research team recently observed this compound in the Columbia River, but no data currently exists on concentrations of its primary breakdown product, guanylurea. This study aims to determine concentrations of these two compounds at several sites in the lower Columbia River by leveraging efforts of a volunteer network coordinated through Columbia River Keeper and through an ongoing sampling program to characterize salmon habitats (with the Lower Columbia Estuary Partnership) to obtain samples during different seasons and throughout the river downstream of Bonneville Dam.

The overarching goal of this project is to gain fundamental knowledge about the distribution and fluxes of endocrine disrupting compounds and to probe the mechanisms by which they might degrade (including photolysis and microbial degradation) in order to inform risk assessments and improve predictions for how these compounds might behave in natural environments. The research team plans to engage stakeholders representing several agencies, non-profits, and tribes in the dissemination of data (via websites, meetings, and personal interactions) and in developing strategies for addressing reductions in the loads of these compounds and other CECs through workshops. Researchers will have opportunities to hone their science communication skills through participation in a Science Communication Fellowship through the Oregon Museum of Science and Industry and teaching middle school students through Saturday Academy, an after-school program in Portland, OR.

Strategic Plan Focus Areas: Healthy Coastal Ecosystems,Sustainable Fisheries and Aquaculture

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