Juvenile chinook salmon in the Fraser River estuary have been found to contain a variety of chemicals, including pharmaceuticals and flame retardants, according to a recent study. Researchers gathered samples from hundreds of fish over a two-year period, identifying over 80 contaminants present in the salmon tissue alone, with the likely source being industrial and wastewater sites upstream. Water samples from the salmon habitat were also analyzed, revealing 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 population. David Scott, the lower Fraser research and restoration director at the Raincoast Conservation Foundation, highlighted the widespread presence of pollutants in the fish, ranging from pharmaceuticals and personal care products to pesticides and flame retardants.
The study, supported by the Department of Fisheries and Oceans and conducted in collaboration with the Raincoast Conservation Foundation and Simon Fraser University, focused on the Harrison River chinook stock in the Fraser River estuary. The findings identified 16 priority contaminants, including organic chemicals and pharmaceuticals, with PBDE-penta-total, a flame retardant, being the sole priority contaminant detected in the salmon tissue samples. Additionally, 15 other priority contaminants, such as cocaine and pesticides, were found in the habitat water samples.
Moreover, eight “watchlist” chemicals posing biological risks were detected in the salmon tissue samples, further underscoring the potential dangers to the ecosystem. Tanya Brown, a study co-author and assistant professor at Simon Fraser University, emphasized the alarming combination of chemicals that the fish are being exposed to, noting the need for expanded monitoring and concern over the vast number of unmeasured chemicals in the marketplace.
Similar research conducted in Washington state’s Puget Sound has shown that synthetic organic chemicals can inhibit chinook salmon growth. Molly Shuman-Goodier, a research scientist with the Washington Department of Fish and Wildlife, highlighted the potential long-term impacts of these contaminants on fish populations. The study’s implications extend to orcas, as southern resident killer whales that feed on chinook salmon may also be affected by these contaminants.
The research findings have significant implications for public policies and individual actions in managing chemical exposure. Scientists stress the importance of responsible disposal of pharmaceuticals and heightened awareness of personal choices to mitigate the impact of these contaminants on aquatic ecosystems and human health.