New Zealand Food Safety is advising the public not to collect or consume shellfish gathered from some southern beaches on Waiheke Island due to the possible presence of biotoxins.
“An algae-like organism called Okeania spp has been detected on beaches at Surfdale and Blackpool on the southern side of Waiheke Island,” says New Zealand Food Safety deputy director-general, Vincent Arbuckle.
“Okeania spp is a cyanobacteria that forms dark-coloured mats of slimy material when it washes up on the beach. As these cynobacterial mats decompose, they turn into a stinky sludge. It can also produce a toxin called Lyngbyatoxin-A, which can cause skin and eye irritation and respiratory issues.
“Samples of the mats were collected by Auckland Council for testing, which has confirmed the presence of Okeania spp and Lyngbyatoxin-A.
“Because of the potential health risks, New Zealand Food Safety is advising the public not to consume shellfish from Surfdale and Blackpool beaches, as well as to avoid coming into contact with the cyanobacterial mats.
“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).
“The risks of this toxin contaminating shellfish is unknown, so this warning is precautionary until we can find out more. It’s important to note that cooking shellfish will not destroy biotoxins.
“At this stage, finfish are not included in this public health warning, but we advise people to gut the fish and discard the liver before cooking.”
New Zealand Food Safety 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. You are also advised to contact your nearest public health unit and keep any leftover shellfish for testing.
“New Zealand Food Safety is keeping an eye on the situation and will notify the public of any changes,” says Mr Arbuckle.
Commercially harvested shellfish – sold in shops and supermarkets or exported – is subject to strict water and flesh monitoring programmes by New Zealand Food Safety to ensure they are safe to eat.