Nelson Marlborough District Health Board's medical officer of health has warned the public not to take or eat shellfish from Queen Charlotte Sound.
Dr Jill Sherwood said the area affected is all of Queen Charlotte Sound, including Tory Channel.
"Routine testing of shellfish in Tory Channel has shown higher than acceptable levels of the toxins that can cause paralytic shellfish poisoning," she said.
"Testing has also shown increased numbers of the phytoplankton that produce this toxin in Queen Charlotte Sound. Previous experience indicates toxin levels are likely to be unsafe there as well."
Symptoms of poisoning were numbness and tingling around the mouth, face or extremities; difficulty swallowing or breathing, dizziness and double vision. In severe cases, paralysis and respiratory failure can occur.
Acute symptoms usually occur within 12 hours of consuming shellfish. She advised people not to eat kina, mussels, pipi, tuatua, oysters and cockles harvested from the affected areas since February 19.
"Scallops, paua, crab, and crayfish may still be eaten if the gut [and skirt of scallops] was completely removed prior to cooking. If the gut was not removed its contents could contaminate the meat during the cooking process.
"Cooking affected shellfish does not remove the toxin," she said. Fish, such as snapper, cod, gurnard, and terakihi were not affected by the toxin algae and are still safe to eat, she said.
A shellfish closure map shows the affected area is all of Queen Charlotte Sound from a line drawn between Cape Jackson, across to Cape Koamaru,including Tory Channel out to East Head and West head.
"Continued monitoring of the situation is planned, but in the meantime people should not take shellfish from this area
"Any shellfish that has been harvested since February 19, but not yet eaten, should not be consumed. Freezing the shellfish does not kill or remove the toxin."
For more information about the safety of shellfish contact the on call health protection officer on Blenheim (03) 520 9999.
- The Marlborough Express
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