Marine biotoxin alerts.

Shellfish and seawater samples around New Zealand are tested each week to ensure they are not contaminated with biotoxin from blooms of algae. Public warnings are issued when shellfish are not safe to eat. This page contains information relating to the non-commercial (recreational and traditional) taking of shellfish only.

All commercially harvested shellfish are taken from growing areas which have strict biotoxin monitoring programmes in place. Testing for biotoxins in commercial areas occurs on a regular basis and harvesting of shellfish does not occur when there are marine biotoxin risks.

This page is updated as soon as new information comes to hand. All the warnings on this page are current and remain in force.

Marine biotoxin warnings currently in force

North Island

North Island contaminated areas

Hokianga Harbour

The Health Protection Unit of Northland District Health Board continues to advise people not to consume shellfish from the Hokianga Harbour. This public health warning has been issued due to the persistence of Microcystin Toxins above safe levels in shellfish.

Shellfish in the Hokianga Harbour were tested for Microcystins after a bloom of toxic Cyanobacteria occurred in Lake Omapere which drains into the Hokianga Harbour.

High levels of microcystins are frequently associated with the death of animals consuming contaminated water. Human deaths from consumption on microcystins have not been well reported but it is acutely toxic in animal studies and they are thought to cause liver damage in humans. Human fatalities have also occurred when water used for dialysis of patients with kidney failure has become contaminated.

For further information contact: Northland District Health Board (09) 430 4100

Bay of Plenty - Reminder about toxic shellfish along parts of the Bay of Plenty coast- 27/03/13

Bay of Plenty residents and visitors need to continue to be aware of the risk of paralytic shellfish toxin poisoning. “Levels of toxin found in shellfish along parts of the Bay of Plenty coastline remain high. Shellfish in the affected area should not be taken or eaten,” says Dr Neil de Wet, Medical Officer of Health.

The current health warning has been in place since August 2012. Toi Te Ora has a new Twitter account that people can follow for up-to-date information about the toxic shellfish warning and other health warnings and alerts. The Twitter account to follow is @TTOHealthAlerts. In addition to Twitter up-dates, Toi Te Ora provides information about the toxic shellfish health warning and other warnings and alerts through these channels:

• Phone: 0800 221 555
• Website: www.ttophs.govt.nz/health_warnings
• Email alerts for subscribers: www.ttophs.govt.nz/alert
• Signage at locations (e.g. shellfish health warning signs at affected beaches)

The Medical Officer of Health strongly advises against the collection of shellfish from Tairua on the east coast of the Coromandel Peninsula, south to Waihi Beach and along the Bay of Plenty coast to Whakatane Heads in the Eastern Bay of Plenty. The warning includes Tairua Harbour as well as Tauranga Harbour, Maketu and Waihi estuaries, Matakana and Motiti Islands, and all other islands along this coastline.

The health warning applies to all bi-valve shellfish including mussels, pipi, tuatua, cockles, oysters, scallops as well as cat’s eyes, snails and kina (sea urchin). Shellfish containing toxic levels of paralytic shellfish poison don't look or taste any different from shellfish that are safe to eat. Cooking or freezing the shellfish does not remove the toxin. Paua, crayfish and crabs can still be taken but as always, the gut should be removed before consuming.

Consumption of shellfish affected by the paralytic shellfish toxin can cause numbness and tingling around the mouth, face, hands and feet; difficulty swallowing or breathing; dizziness; double vision; and in severe cases, paralysis and respiratory failure. These symptoms can start as soon as 1-2 hours after eating toxic shellfish and usually within 12 hours. Anyone suffering illness after eating shellfish should seek urgent medical attention.

For more information, contact:

Debbie Phillips
Communications Officer
Ph: 07 577 3793
Mob: 021 791 814
After hours: 07 579 8000 and ask for the on call Medical Officer of Health

South Island

There are no biotoxin warnings currently in place for the South Island

Please note:

Warnings about unsafe areas are subject to change. The public should contact their local health protection officers at District Health Boards if they are in doubt about where they should take shellfish.

Public health unit contacts