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Biotoxin discovered in B.C. shellfish for first time

About 60 people became sick recently from a biotoxin found in about 30,000 pounds of mussels that were harvested this summer near Cortes Island.

About 60 people became sick recently from a biotoxin found in about 30,000 pounds of mussels that were harvested this summer near Cortes Island.

The toxin is called diarrhetic shellfish poisoning (DSP), which had never previously been detected in B.C. waters. It is more common in Europe, Asia and the east coast of Canada.

"It happened exactly on Aug. 3," said Roberta Stevenson, executive director of the Comox-based B.C. Shellfish Growers Association. "Some mussels from a very reputable mussel farmer ended up having this DSP in it.

"The reason that it wasn't found out until some people did get sick was because we don't traditionally check for it every time we harvest. It's never been found here before.

"So it's a new thing, but believe me, from now on it will be tested for every time we sell mussels."

The Canadian Food Inspection Agency issued a recall and warning early-August.

The biotoxin is not fatal but ingesting DSP can cause diarrhea, nausea and cramps. Symptoms last about three days.

The biotoxin has caused problems in other countries. In 1984, for instance, a DSP outbreak shut down Sweden's mussel industry for nearly a year.

"Lots of places in the world have lots of DSP; we've just never had it on the West Coast. So it's a new risk," Stevenson said, noting the toxin was found around the same time in Olympia, Wash.

''We're kind of befuddled. But if the public is getting product from a registered processing facility, they need to rest assured that it's still extremely safe. Really, the benefits of eating our shellfish certainly outweigh any risks. It'll never happen again as far as we're concerned. The protocol for testing, just like we test for red tide and everything else, will now include testing for DSP."

Though fewer than one per cent of people who ate the mussels became ill, Stevenson said the outbreak is nevertheless inexcusable.

"The ocean is going through a lot of changes right now," she said. "The ocean is suffering from ocean acidification, which is a huge concern for shellfish as far as their ability to reproduce...We don't know why, but we'll figure it out. Farmers are used to this. If it's not one thing it's another."

The association is hosting a fall workshop in Baynes Sound where specialists will offer testing tips that are used in places where DSP is common.

Half of B.C.'s farmed shellfish is grown in Baynes Sound.

reporter@comoxvalleyrecord.com