New Zealand Food Safety (NZFS) is advising the public not to collect or consume shellfish gathered from the Northland east coast because of paralytic shellfish toxins.

In addition, it has extended an existing shellfish biotoxin warning from Cape Kidnappers right up to East Cape.

“Routine tests on mussels from Houhora have shown levels of paralytic shellfish toxins over the safe limit,” says NZFS deputy director-general Vincent Arbuckle. “The warning extends from Cape Karikari north to Kokota (the Sandspit), just south of Parengarenga Harbour.”

“The current warning in Hawkes Bay has now been extended to extend from Cape Kidnappers right up to East Cape. Levels of paralytic shellfish toxins are increasing and the latest results from Tolaga Bay mussels have risen dramatically and are now 11 times over the safe limit”.

As algal blooms increase in size, the levels of toxins in shellfish can reach higher levels.

“Please do not gather and eat shellfish from these affected areas because anyone doing so could get seriously sick.

“Cooking the shellfish does not remove the toxin, so shellfish from these areas should not be eaten.”

Symptoms of paralytic shellfish poisoning usually appear within 10 minutes to 3 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 prior to cooking, as toxins accumulate in the gut. If the gut is not removed, its contents could contaminate the meat during the cooking process. Finfish are not affected by this public health warning.

NZFS has had no notifications of associated illness.

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

You are also advised to contact your 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,” says Mr Arbuckle.

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.