A recent study has revealed the presence of numerous chemicals, including pharmaceuticals and flame retardants, in juvenile chinook salmon residing in the Fraser River estuary. Researchers conducted extensive sampling on hundreds of fish from 2019 to 2021, identifying over 80 contaminants solely in the salmon tissue, likely originating from industrial and wastewater facilities upstream. Additionally, water samples from the salmon habitat were analyzed, uncovering 130 different contaminants.
Experts are concerned that these chemicals could be adversely impacting the growth, behavior, and overall health of the chinook salmon population. David Scott, the lower Fraser research and restoration director at the Raincoast Conservation Foundation (RCF), emphasized the direct link between wastewater contamination and fish health, citing various pollutants ranging from pharmaceuticals and personal care products to pesticides and flame retardants.
The study focused on the Harrison River chinook stock developing in the Fraser River estuary, with tissue and habitat samples collected from multiple locations. According to the research findings, 16 of the identified chemicals were classified as “priority” contaminants due to their potential adverse effects, with the flame retardant PBDE-penta-total being the sole priority contaminant found in salmon tissue samples. The remaining 15 priority contaminants, including cocaine and pesticides, were detected in the water samples from the habitat.
Moreover, eight additional “watchlist” chemicals posing elevated biological risks were found in the salmon tissue samples, consisting of pesticides, pharmaceuticals, and other organic chemicals. The study, primarily funded by the Department of Fisheries and Oceans in collaboration with the RCF and Simon Fraser University, highlighted the need for continuous monitoring and assessment of the chemicals affecting the fish population.
Tanya Brown, a study co-author and assistant professor at Simon Fraser University, expressed concerns about the unmeasured chemicals that fish might be exposed to, stressing the alarming combination of various contaminants affecting the fish. The study’s implications extend beyond the fish population, with potential impacts on the broader ecosystem, including orcas that feed on chinook salmon.
Researchers in Washington state’s Puget Sound have been conducting similar studies on contaminant levels in fish habitats for over three decades. They have observed synthetic organic chemicals inhibiting chinook growth, with potential long-term repercussions on the fish population and the marine ecosystem. The study findings underscore the importance of managing chemicals effectively through public policies and individual actions, such as proper disposal of pharmaceuticals to mitigate environmental impacts.
The research sheds light on the critical need for continued monitoring and conservation efforts to safeguard the health and sustainability of fish populations in the Fraser River estuary and beyond.