Toxic ‘forever chemicals’ detected in dead sea otters collected off B.C. coast

A baby sea otter named Tofino shakes off water while swimming at the Vancouver Aquarium's Marine Mammal Rescue Centre, in Vancouver, B.C., Tuesday, July 30, 2024. THE CANADIAN PRESS/Darryl Dyck

VANCOUVER — A new study says sea otters in British Columbia have been found to be contaminated with so-called forever chemicals found in food packaging, non-stick cookware, cosmetics, electronics and other products.

The study published in the journal Environmental Toxicology and Chemistry says samples from dead otters collected off the B.C. coast between 2016 and 2021 showed varying concentrations of several chemicals in the animals’ liver and skeletal muscle tissue.

Lead author Dana Price, a marine mammal researcher pursuing a master’s degree at the University of British Columbia, said the findings were “unfortunately” not surprising given similar research on sea otters in other parts of the Pacific Ocean.

It’s the first study to examine forever chemical accumulation in B.C. sea otters, filling a “geographical gap” after the chemicals have been found in the animals in other locations, including California, Washington, Alaska and Russia.

Researchers found otters collected near major cities and shipping routes had triple the concentrations of the contaminants, but the threat to the animals’ health posed by the chemicals is unknown.

“It was interesting to see the trend within our data where the sea otters that lived closer to more people, places like Tofino, Victoria, had higher concentrations than those that lived further up the coast in a bit more isolated areas,” Price said in an interview Tuesday.

Price said testing also showed that a sea otter that died shortly after birth had “fairly high concentrations” of forever chemicals, indicating that some contaminants are passed on from the mother.

Among Price’s co-authors were veterinary pathologist Stephen Raverty with B.C.’s Agriculture Ministry and Paul Cottrell from the Fisheries Department, who handled sample collection and necropsies on the animals.

She said the contaminants weren’t found to factor into the otters’ deaths, but other research on the animals in California did indicate that the chemicals played a role in their deaths.

But Price said sea otters in that study showed much higher concentrations than the samples collected in B.C., and forever chemicals “are just one part of the very, very big picture of potential threats that sea otters are exposed to.”

She said she’s also studying other contaminants from oil spills, wildfires and plastics with a particular interest in sea otters because they live close to shore with a lot of exposure to human activity.

The study notes that sea otters were wiped out in B.C. by the fur trade between the mid-1700s and early 1900s, but were reintroduced after 89 animals from Alaska were relocated between 1969 and 1972.

The study says the otter population was estimated to be more than 8,000 by 2017, and Price said “there’s been a lot of attention on their population growth and overall their recovery.”

She said there isn’t any historical data from the time before the chemicals became widely used.

“But the best thing that we can do now is get a snapshot of where we’re at so we can look back maybe 10 years from now and see if anything’s changed,” she said.

The study says sea otters don’t migrate or travel far from where they live, which makes them “useful indicators for region specific analysis of contaminant accumulation from food sources often harvested and consumed by humans.”

Researchers found eight different compounds that have entered the food chain and accumulated in the sea otters, a “keystone species” that can shed light on contamination levels of ecosystems near shorelines.

The study said the long-term consequences of forever chemical accumulation remains unknown, but it’s the first study of its kind on the otters in the region to help with future studies and their recovery efforts.

Price said the study didn’t pinpoint the source of forever chemical contamination, but they were invented for many uses and found in many different products that could end up leaching into ecosystems.

“It’s hard to say exactly where they came from,” she said. “They just come at a price to the environment.”

This report by Darryl Greer of The Canadian Press was first published Nov. 4, 2025.