Warning after unsafe levels of toxin detected in Hawke’s Bay shellfish

New Zealand Food Safety is advising the public not to collect or consume shellfish gathered from Hawke’s Bay due to the presence of toxins. Photo / Ministry for Primary Industries

New Zealand Food Safety (NZFS) is advising the public not to collect or consume shellfish gathered from a large stretch of Hawke’s Bay coastline after unsafe levels of toxins were detected.

NZFS deputy director-general Vincent Arbuckle said routine tests on mussels from Pania Reef in Napier showed levels of paralytic shellfish toxins over the safe limit of 0.8mg/kg set by NZFS.

“The warning extends from Cape Kidnappers, north to Mohaka River,” Arbuckle said.

“Please do not gather and eat shellfish from this area because anyone doing so could get sick. Cooking the shellfish does not remove the toxin.”

Symptoms of paralytic shellfish poisoning usually appear 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 and, in severe cases, death.

Pāua, crab and crayfish may still be eaten if the gut has been completely removed before cooking, as toxins accumulate in the gut.

If the gut is not removed, its contents could contaminate the meat during the cooking process.

NZFS had no notifications of associated illness as of Wednesday evening.

If anyone becomes ill after eating shellfish from an area where a public health warning has been issued, they are advised to phone Healthline for advice on 0800 61 11 16 or seek medical attention immediately.

They are also advised to contact their nearest public health unit and keep any leftover shellfish in case it can be tested.

“NZFS is monitoring shellfish in the region and will notify the public of any changes to the situation,” Arbuckle said.

According to the Ministry for Primary Industries (MPI), paralytic shellfish poisoning is caused by a group of chemicals called saxitoxins and gonyautoxins.

“These chemicals all differ in their toxicity to humans, and their proportions may vary depending on the species of shellfish and the species of algae producing the toxin,” the MPI website states.

Commercially harvested shellfish sold in shops and supermarkets or exported is subject to strict water and flesh monitoring programmes by NZFS to ensure they are safe to eat.