A recent study revealed the presence of various chemicals in young chinook salmon residing in the Fraser River estuary, including pharmaceuticals and flame retardants. Researchers analyzed hundreds of fish samples collected from 2019 to 2021, identifying over 80 contaminants solely in the salmon tissue, likely originating from industrial and wastewater sites upstream. The team also examined water samples from the salmon habitat, detecting 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 at the Raincoast Conservation Foundation (RCF), highlighted the significant influence of wastewater on fish, citing a range of pollutants 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 samples collected from multiple sites. According to the study findings, 16 of the identified chemicals were classified as “priority” contaminants with potential adverse effects, including organic chemicals and pharmaceuticals. PBDE-penta-total, a flame retardant, was the main priority contaminant found in salmon tissue samples, while others like cocaine and pesticides were detected in habitat water samples.
Additionally, eight “watchlist” chemicals posing elevated biological risks were found in salmon tissue samples, including pesticides, pharmaceuticals, and organic chemicals. The study, primarily funded 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 the likelihood of additional untested chemicals affecting the fish.
Similar research in Washington state’s Puget Sound has shown the impact of synthetic organic chemicals on chinook salmon growth over the past 30 years. Experts highlighted the potential long-term consequences of inhibited growth on salmon populations. The study also raised concerns about the implications for orcas, as chinook salmon are a vital part of their diet. With human consumption of chinook salmon also in the picture, monitoring and managing these chemical contaminants becomes crucial for public health and environmental sustainability.
The researchers suggested that individual actions, such as proper disposal of pharmaceuticals, could contribute to mitigating the impact of these contaminants. The findings from these studies may guide future management strategies, including public policies and personal choices, to address the presence of harmful chemicals in aquatic ecosystems.
