UBC Theses and Dissertations
Copper, cadmium and silver content and biomagnification in Strait of Georgia herring and Burrard Inlet English sole Hassanaghaei, Mina
The Strait of Georgia (SoG) is a semi-enclosed water body in the Northeast Pacific Ocean. Burrard Inlet, located on the central and eastern side of SoG, is an important basin, hosting the city of Vancouver and the Port of Vancouver. For thousands of years, fish and shellfish in SoG have been important sources of food for local First Nations communities. In the last 150 years, urbanization in this area has increased the sources of metal pollutants into SoG. The bioaccumulation of these metals in fish and shellfish poses a threat for direct human consumption, and for marine mammals in the highest trophic level in the SoG food web. As part of the ambient SoG and Burrard Inlet Monitoring Programs, and in collaboration with Metro Vancouver and Fisheries and Ocean Canada, I investigated the Cu, Cd and Ag content of English sole and juvenile herring, collected from 6 stations in Burrard Inlet and 8 stations across SoG, respectively. The metal content of whole-body fish was lower for English sole than for herring. For both fish, the metal content was highest for Cu, moderate for Cd and lowest for Ag. Some significant spatial differences were found for Cd and Cu content in herring and English sole. Using previous data, I calculated the accumulation of Cu, Cd and Ag from seawater by phytoplankton, zooplankton and fish, and showed that it was highest for Ag and lowest for Cd. Estimates of trophic magnification factor for the 3 lowest trophic levels in SoG indicated that Ag and Cu are similarly and greatly biodiminished, while Cd is also biodiminished but to a lesser extent. Based on international and local permissible levels of Cu, Cd and Ag for edible fish tissues, juvenile herring in SoG and English sole in Burrard Inlet are safe for human consumption.
Item Citations and Data
Attribution-NonCommercial-NoDerivatives 4.0 International