Health and fisheries officials say three people are recovering from what's likely paralytic shellfish poisoning, after eating butter clams harvested off B.C.'s North Coast.
Officials say the clams were harvested in November 2018 on Dundas Island, about 44 kilometres from Prince Rupert, B.C., but were kept in a freezer and only recently eaten.
Experts said that freezing or cooking poisoned shellfish can amplify any toxins they contain.
'Could have been near death for sure'
"Paralytic shellfish poisoning can be deadly," said Elysha Gordon, a biologist and shellfish sanitation expert with the Department of Fisheries and Oceans. "So in this case, it could have been near death for sure."
Gordon says during harmful algal blooms — also called red tides — toxins can accumulate in bivalve shellfish such as clams as they filter feed.
Gordon says the neurotoxins don't harm the clams, but can kill people in just 30 minutes. Symptoms of paralytic shellfish poisoning include numbness around the lips and face, difficulty breathing and paralysis of respiratory muscles.
All 3 are recovering
"It can be very serious," said Northern Health authority medical health officer Dr. Rakel Kling. She said all three people sought immediate medical attention, have since been discharged from hospital and are recovering at home.
The First Nations Health Authority said the B.C. Centre for Disease Control is continuing to investigate by testing leftover food samples as well as clinical samples from patients.
The Department of Fisheries and Oceans said the toxic clams were harvested from a closed area where there had been no testing for toxins. The remote area is a popular fishing spot local Indigenous communities.
"If an area isn't tested [by DFO] we can't deem it safe for human consumption," said DFO's Gordon. "Butter clams can retain toxins for up to a year and sometimes two years."
"Do not just eat at your own risk [from remote places] because honestly, it's not worth it. Do you really want to risk your life for something that could kill you so quickly?"