NPRB: The Physiological Effects of Dispersants and Dispersed Oil on a Sentinel Cold Water Species, the Bay Mussel

Scope of Work:

Increasing oil development around Alaska also elevates the risk for another oil spill. Dispersants are chemicals applied to oil spills to break the oil into droplets in an effort to accelerate natural degradation processes. Dispersed oil, or the dispersant itself, may be more toxic than oil alone. However, there is limited research on the effect of dispersed oil on cold-water species and ecosystems. Therefore, we propose to conduct exposure tests with bay mussels in seawater with non-dispersed oil, Corexit 9527, Corexit 9500, oil dispersed with different concentrations of Corexit 9527, and oil dispersed with different concentrations of Corexit 9500 and then assess how the different treatments influence mussel health at different time points. Corexit 9527 is stored in Alaska for use in the event of an oil spill, and Corexit 9500 is a newer version ofCorexit9527 that may also be used. Bay mussels, which are found in arctic and subarctic coastal waters, will be used in experiments because they are of commercial and subsistence value, are easy to collect for monitoring projects, and our laboratory has validated methods to assess the effects of contaminants on their health. Determining the influence of dispersed oil on mussel health will be important for agencies to determine where dispersants can safely be used in arctic and subarctic regions in order to protect sensitive habitats. Many communities depend on coastal resources, including mussels, so it is imperative to know if dispersed oil is more toxic than oil alone. This project will be valuable for increasing our knowledge about the risk of using dispersants during an oil spill in the arctic and subarctic ecosystems.

This project is jointly funded by the North Pacific Research Board and OSRI.