OTTAWA — Canadians are buying contaminated fish from China and Vietnam, the Consumers' Association of Canada says.

Citing the use of a dangerous fungicide on fish farms, the association wants the federal government to ban the importing of certain fish products from those two Asian countries.

"A cancer-causing banned fungicide, Malachite Green, is being used by fish farmers in some Asian countries, particularly Vietnam and China.'' Bruce Cran, president of the association, said Friday in a release.

"Independent labs tests of these fish purchased at Canadian supermarkets have shown that consumers are being sold these contaminated fish."

In tests done this year by the Canadian Food Inspection Agency, 43 per cent of farmed fish from Vietnam were contaminated with the cancer-causing agent, the association said in a release.

"This is a stunning number,'' Cran said.

He said the CFIA now is testing just five fish among the thousands that come in as part of each shipment.

"If the five fish tested happen to be clean ones, the rest of the shipment has then been approved for sale, even though it can be full of contaminated fish,'' Cran said.

"That's what happened recently when these fish from an approved shipment were purchased at a British Columbia supermarket. These shipments went through the CFIA inspection process, were approved, then sold to consumers even though they were contaminated. This is not acceptable."

Cran said the CFIA has not publicly advised Canadian consumers about the contamination.