Canada has issued a nationwide warning after mussels personally harvested recently from a closed area of New Brunswick resulted in illnesses from Paralytic Shellfish Poisoning (PSP).

The Canadian Food Inspection Agency (CFIA) warned the public against consuming personally harvested bivalve shellfish from and around closed harvest areas.

These bivalve shellfish could contain paralytic shellfish toxins that can cause serious and potentially fatal illness if consumed, CFIA said.

The CFIA has determined that the reported illnesses were not associated with a commercial or purchased product.

However, consumers are advised to exercise caution when purchasing shellfish. Consumers can inquire at the point of purchase if the shellfish they are buying has proper documentation to ensure that it was harvested from an approved or open area.

Consumers are also advised that the levels of paralytic shellfish poisoning (PSP or red tide) are currently high and several areas are now closed to harvesting bivalve shellfish due to unacceptable PSP levels.

For more information on closures of shellfish harvesting areas, Canadians were advised to call the nearest office of the Department of Fisheries and Oceans Canada.

Paralytic shellfish toxins are a group of natural toxins that sometimes accumulate in bivalve shellfish that include oysters, clams, scallops, mussels and cockles. Non-bivalve shellfish, such as whelks, can also accumulate these toxins.

These toxins can cause PSP if consumed. Symptoms of PSP include tingling and numbness of the lips, tongue, hands, and feet, and difficulty swallowing. In severe situations, this can proceed to difficulty walking, muscle paralysis, respiratory paralysis and death in as quickly as 12 hours.