“Crude oils are a complex mixture of chemicals, represent a pervasive environmental stressor. Canada sits on the world’s third largest crude oil reserve, found as bitumen in the Athabasca oil sands. Ninety-eight percent of Canada’s oil comes from the oil sands, and 99 percent of our exports go to the US,” said study author Sarah Alderman. “As plans to bolster the export capacity of this resource intensify, so too do concerns for the added risk of spills and environmental contamination.”
New pipeline projects, including the Trans Mountain Expansion Project, have the potential to increase diluted bitumen shipped through salmon habitat to seaports on the West Coast.
Alderman’s research has shown that crude oil exposure seems to be toxic to the fishes’ hearts, including molecular- and tissue-level changes that could potentially impair their ability to successfully migrate between freshwater and ocean, as well as the fishes’ ability to acclimate to saltwater. The ability of salmon to migrate – from freshwater at birth to saltwater, where they grow to adulthood, and back to freshwater for spawning– is natural and necessary throughout the course of their life and reproductive cycle.
Alderman found that crude oil exposure early in fish development can lead to long-term consequences, including mortality months after fish are removed to uncontaminated water and brain changes that are apparent for nearly a year after exposure. Her research also revealed changes to plasma proteins that signal damage to tissues and biomarkers that could be used to test whether an animal has been exposed to crude oil.
Alderman’s research was made in collaboration with researchers at Simon Fraser University and the University of British Columbia. Findings were reported by EurekAlert, an online publication of the American Association for the Advancement of Science, on Oct. 28, the same day as they were to be presented at the American Physiological Society’s Comparative Physiology: Complexity and Integration conference in New Orleans, Louisiana.
Materials provided by American Physiological Society. Note: Content may be edited for style and length.