Spatial analysis of contaminant exposure in Snohomish Chinook

Investigator: Sandie O’Neill (WDFW)

Juvenile salmon are captured by beach seine in Eby Slough on the Snohomish River.

Contaminant inputs to Puget Sound may affect the health of juvenile Chinook salmon, impact marine survival, and limit population recovery. Previous research found PBDE (flame retardant) levels high enough to alter immune response in 100% of Snohomish River Chinook salmon. The purpose of this project is to identify locations of highest PBDE exposure in the Snohomish River watershed and to assess actions to mitigate PBDE sources.PBDE concentrations and contaminant patterns in Chinook salmon are compared with adjacent shoreline land-use along the Snohomish River system to identify the relative contribution of waste-water treatment plants and stormwater. This project also provides a model for identifying contaminant locations and sources in other Puget Sound watersheds.