A map showing the area covered by the shellfish biotoxin alert extends from Cape Runaway south to Blackhead Point, just north of Pōrangahau. Photo: CC 4.0 BY-SA / Ministry for Primary Industries
The food safety authority is warning people on the East Coast not to collect shellfish, after Hicks Bay mussels were found with three times the safe limit of paralytic shellfish toxins.
It is an extension of an earlier warning to now cover the area from Cape Runaway all the way south to Blackhead Point, just north of Pōrangahau.
Food Safety deputy director-general Vincent Arbuckle said a spreading algal bloom off the East Coast was producing the toxin, which then accumulated in shellfish guts and flesh.
He said there had not been any reported illnesses so far.
"Affected shellfish include bivalve shellfish such as mussels, oysters, tuatua, pipi, toheroa, cockles, and scallops, as well as pūpū (cat's eyes), Cook's turban and kina (sea urchin)," he said.
"Cooking the shellfish does not remove the toxin, so shellfish from this area should not be eaten."
Finfish were not included in the warning, but gutting the fish and discarding the liver before cooking was advised.
Pāua, crab, and crayfish could still be eaten if the gut had been completely removed prior to cooking, as toxins accumulated in the gut.
Symptoms of paralytic shellfish poisoning usually appeared within 10 minutes to three hours of eating and may include:
- Numbness and a tingling (prickly feeling) around the mouth, face, hands, and feet
- Difficulty swallowing or breathing
- Dizziness and headache
- Nausea and vomiting
- Diarrhoea
- Paralysis and respiratory failure
- In severe cases, death