Juvenile chinook salmon in the Fraser River estuary have been found to contain a wide array of chemicals, including pharmaceuticals and flame retardants, according to a recent study. Researchers gathered samples from hundreds of fish over the span of two years and identified over 80 contaminants in the salmon tissue alone. These contaminants are believed to originate from industrial and wastewater sites upstream. Water samples from salmon habitats also revealed the presence of 130 different contaminants.
The research team expressed concerns that these chemicals could be negatively impacting the growth, behavior, and overall health of the chinook salmon. David Scott, the lower Fraser research and restoration director for the Raincoast Conservation Foundation (RCF), highlighted the significant presence of pollutants in the fish, ranging from pharmaceuticals and personal care products to pesticides and flame retardants.
The study, funded largely by the Department of Fisheries and Oceans and conducted in collaboration with the RCF and Simon Fraser University, identified 16 “priority” contaminants with potential adverse effects, including organic chemicals and pharmaceuticals. One such priority contaminant found in salmon tissue samples was the flame retardant PBDE-penta-total, while the remaining 15 were detected in the habitat water samples, including substances like cocaine and pesticides.
Additionally, eight other “watchlist” chemicals associated with elevated biological risks were detected in salmon tissue samples, comprising pesticides, pharmaceuticals, and other organic chemicals. Tanya Brown, a study co-author and assistant professor at Simon Fraser University, emphasized that the research focused on organic chemicals, suggesting that there may be additional unidentified chemicals affecting the fish.
Similar monitoring efforts in Washington state’s Puget Sound have shown that synthetic organic chemicals can hinder the growth of chinook salmon. Molly Shuman-Goodier, a research scientist with the Washington Department of Fish and Wildlife, highlighted the potential long-term impacts of these contaminants on the fish population and ecosystem.
Furthermore, the findings have implications for the broader marine ecosystem, particularly for southern resident killer whales that prey on chinook salmon. These whales already exhibit high levels of contaminants, reflecting the transfer of pollutants up the food chain. The study underscores the importance of managing chemicals effectively, both through public policies and individual actions, to mitigate the impact on marine life and human health.
