A recent study revealed the presence of various chemicals, including pharmaceuticals and flame retardants, in young chinook salmon inhabiting the Fraser River estuary. Over 80 contaminants were detected in the salmon tissue, with industrial and wastewater sites upstream believed to be the primary sources. Water samples from the salmon habitat also contained 130 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 at the Raincoast Conservation Foundation (RCF), highlighted the wide range of pollutants found in the fish, such as pharmaceuticals, personal care products, pesticides, and flame retardants.
The study focused on the Harrison River chinook stock in the Fraser River estuary, analyzing tissue and habitat samples at various locations. Priority contaminants, including organic chemicals and pharmaceuticals, were among the 16 chemicals identified as potentially harmful. The flame retardant PBDE-penta-total was detected in salmon tissue, while other priority contaminants like cocaine and pesticides were found in the water samples.
Additionally, eight “watchlist” chemicals with elevated biological risks were discovered in salmon tissue, including pesticides, pharmaceuticals, and organic chemicals. The study, supported by the Department of Fisheries and Oceans and conducted in collaboration with the RCF and Simon Fraser University, emphasized the need for further monitoring due to potential undetected chemicals.
Tanya Brown, a study co-author and assistant professor at Simon Fraser University, warned about the alarming combination of chemicals affecting the fish. She highlighted the vast number of chemicals in the marketplace that pose monitoring challenges and raised concerns about the need for additional oversight.
Similar research conducted in Washington state’s Puget Sound has shown that synthetic organic chemicals can hinder chinook growth. Molly Shuman-Goodier, a research scientist at the Washington Department of Fish and Wildlife, emphasized the importance of documenting these impacts in the field and the potential long-term effects on chinook populations.
The study also highlighted the implications for orcas, as chinook salmon serve as a vital food source for southern resident killer whales. Scott pointed out the high contaminant levels in killer whales and the exceeding of human health thresholds in Puget Sound chinook. Scientists on both sides of the border believe that this research can inform better chemical management practices at various levels, including public policies and individual actions.