New Zealand Food Safety has issued a public health warning against collecting or eating shellfish from the Bay of Plenty coast between Maketu Beach and Waihi Beach after routine tests found paralytic shellfish toxin above safe limits in pipi.

The warning covers the area from just north of the Maketu Beach estuary to the northern end of Waihi Beach. It applies to bivalve shellfish such as mussels, oysters, tuatua, pipi, toheroa, cockles and scallops, and also to pūpū (cat’s eyes) and Cook’s turban. Cooking will not remove the toxin.

Officials say a naturally occurring algal bloom in the region is spreading. As shellfish filter-feed, the toxin can build up in their gut and flesh.

Pāua, crab and crayfish can still be eaten if the gut is completely removed before cooking. Finfish flesh is not affected by this warning, but fish should be gutted and the liver discarded before cooking.

Symptoms of paralytic shellfish poisoning can appear from 10 minutes to three hours after eating affected shellfish. Anyone who becomes unwell after eating shellfish from the area should call Healthline on 0800 611 116 or seek immediate medical attention. People are also advised to contact their public health unit and keep any leftover shellfish for possible testing.

New Zealand Food Safety says no illnesses have been reported and monitoring is ongoing. The public will be notified of any changes, and a map of the affected coastline is available. There are no other alerts currently in place. Commercially harvested shellfish sold in shops or exported is subject to strict monitoring and remains safe to eat.