Some of B.C.'s salmon are swimming in a 'chemical soup' that includes cocaine
The biggest river in B.C. is home to hundreds of undesirable contaminants, with a number of them potentially posing a risk to salmon.
A new study from Simon Fraser University (SFU) took water samples from five sites in the Lower Fraser River (the portion of the river from Hope to Salish Sea) estuary, as well as tissue samples from juvenile Chinook salmon that belonged to the Harrison stock.
Researchers then analyzed these samples for nearly 600 contaminants. They found flame retardants, pesticides, industrial chemicals, and pharmaceuticals like prescription drugs, caffeine, and — yes — even cocaine.
“Juvenile Chinook salmon in the Lower Fraser River estuary are feeding and growing in a slurry of contaminants from pharmaceuticals, personal care products to industrial chemicals,” reads the press release from SFU.
Out of the over 200 contaminants, 16 of them exceeded the thresholds for aquatic life with potential for adverse effects, and 23 of them were “worthy of secondary monitoring.”
“Toxicity data is mostly based on single-chemical exposures, but these fish are being exposed to hundreds of chemicals at once. We simply don’t yet understand the additive effects of this chemical cocktail,” said Tanya Brown, marine ecotoxicologist and senior study author, in the release.
Meanwhile, juvenile chinook in the Fraser River estuary are already dealing with a number of stressors, like rising water temperatures and pathogen exposure.
“Harrison Chinook in particular arrive at very small sizes and depend heavily on these habitats for growth prior to entering the ocean,” said Dave Scott, a salmon biologist at Raincoast Conservation Foundation and co-author of the study.
“Contaminant exposure is an additional stressor acting on the same fish during the same critical window.”
SFU pointed out that the findings are worrisome for the marine animals that rely on Chinook salmon, as they could pass on these chemicals up the food chain.
“Chinook salmon from the Fraser River account for up to 90 per cent of the west coast’s endangered Southern Resident killer whales’ diet during the summer months,” said Tanya Brown, marine ecotoxicologist and senior study author, in the release.
There are just over 70 whales left in the Southern Residents population, with three key threats to their numbers: contaminants, declining Chinook salmon, and physical and acoustic disturbance.
Chinook salmon have been suffering decades of population declines, and now 85 per cent of their populations are classified as endangered or threatened.
The Fraser River was also recently listed as one of B.C.’s most endangered rivers in 2026, due to the growing cities and farms on the stretch between Mission and Hope.