Italy and Japan have banned the sale of oilfish because of its gastrointestinal side-effects. ((CBC))

Some Canadians have taken ill after eating oilfish, a low-grade fish barely fit for human consumption thatmay have been mislabelled as cod, the federal food watchdog says.

Oilfish — also known as escolar and snake mackerel — contains high amounts of a waxy type of oil. The fish is indigestible for about one in every two people, causing diarrhea as a side-effect.

More than 600 people in Hong Kong became ill in January, after eating fish they thought was codfish but was in factoilfish. Authorities in Hong Kong determined the oilfish was improperly labelled in Indonesia.

Now it seems the mislabeled oilfish also turned up at Chinese markets in Canada.

The Canadian Food Inspection Agency confirmed it has investigated several cases of diarrhea caused by oilfish that was labelled as something else, such as cod or sea bass.


Steven Lai linked his sickness to eating mislabeled oilfish after reading newspaper stories from Hong Kong. ((CBC))

Steven Lai of Toronto fell victim to the mislabelled fish when he stocked up on what he thought were blue cod steakson sale at a Chinese supermarket after Christmas.

The fish was about half the regular price of cod but it led to oily diarrhea, Lai recalled.

"A few months ago, the Hong Kong newspapers started coming out with this news, and then I realized I had the same complaint," Lai said. "I traced [the sickness] back to eating the fish."

In Vancouver, a supermarket manager has had to reassure customers that the frozen sea bass he sells is the real deal.Customers questioned if the fish was the type that sickened people in Hong Kong, said Ken Lau.

The mislabelled fish was taken off Canadian shelvesbut the Canadian Food Inspection Agency did not issue an advisory.

"The decision to issue a public advisory is made based on the risk posed," said Paul Mayers of the CFIA in Ottawa.

Countries such as Italy and Japan have banned the sale of oilfish because of its gastrointestinal side-effects.

Health officials in Canada said there is no need to go that far. The CFIA plans to release a consumer fact sheet about oilfish so those with delicate stomachs can try to avoid the fish.