Juvenile chinook salmon in the Fraser River estuary have been found to harbor a range of chemicals, including pharmaceuticals and flame retardants. Researchers conducted sampling on hundreds of fish from 2019 to 2021, revealing over 80 different contaminants in the salmon tissue alone, likely originating from industrial and wastewater sites upstream. Water samples from the salmon habitat also showed the presence of 130 contaminants.
The research team expressed concerns that these chemicals could be adversely affecting the growth, behavior, and overall health of the chinook salmon. David Scott, lower Fraser research and restoration director at the Raincoast Conservation Foundation (RCF), emphasized the impact of wastewater pollutants on fish, noting the presence of various pollutants such as pharmaceuticals, personal care products, pesticides, and flame retardants.
The study focused on monitoring Harrison River chinook stock in the Fraser River estuary, examining both their tissue and habitat at multiple locations. Findings revealed 16 priority contaminants with potential adverse effects, including organic chemicals and pharmaceuticals. Notably, the flame retardant PBDE-penta-total was detected in salmon tissue samples, while other priority contaminants such as cocaine and pesticides were found in habitat water samples.
Additionally, eight “watchlist” chemicals posing elevated biological risks were identified in salmon tissue samples, including pesticides, pharmaceuticals, and organic chemicals. The study, funded primarily by the Department of Fisheries and Oceans and conducted in collaboration with the RCF and Simon Fraser University, raised concerns about the broader range of chemicals fish are exposed to beyond those examined in the research.
Tanya Brown, study co-author and assistant professor at Simon Fraser University, highlighted the alarming combination of chemicals affecting fish, stressing the need for increased monitoring and concern over the multitude of unmeasured chemicals in the marketplace. The research could influence future chemical management strategies, be it through public policies or individual actions to address the issue.
Similar investigations in Washington state’s Puget Sound have demonstrated the impact of synthetic organic chemicals on chinook growth, potentially leading to long-term consequences. Researchers emphasized the significance of understanding these effects on the food chain, particularly as chinook salmon, a primary food source for southern resident killer whales, carry chemical loads that can impact marine mammal health. The study findings may guide decisions on chemical management practices at both governmental and personal levels to mitigate risks to wildlife and human health.
