Health Warning - Marine biotoxin in shellfish

Thursday November 3, 2016

Community and Public Health (a division of Canterbury District Health Board) has issued a health warning advising the public not to collect or consume shellfish harvested from the coastline between Ashburton River and Gore Bay.

The Ministry for Primary Industries (MPI) extended the area of the previous health warnings northwards from Motunau Bay and southwards from Akaroa Head after further testing.

Canterbury Medical Officer of Health ​Dr Daniel Williams says routine tests on shellfish samples taken show levels of Diarrhetic Shellfish Poisoning (DSP) toxins of up to 0.26 mg/kg.

"This is above the safe limit of 0.16 mg/kg set by the Ministry for Primary Industry (MPI).  Anyone eating shellfish from this area is potentially at risk of illness," Dr Williams says.

"Mussels, oysters, tuatua, pipi, toheroa, cockles, scallops, catseyes, kina (sea urchin) and all other bivalve shellfish should not be eaten.

Dr Williams warns that cooking shellfish does not remove the toxin.

"Symptoms of diarrhetic shellfish poisoning typically appear within half an hour and can last for 24 hours."

Symptoms may include:

  • Diarrhoea

  • Vomiting

  • Nausea

  • Abdominal cramps 

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.

"If anyone becomes ill after eating shellfish from an area where a public health warning has been issued, phone your usual General Practice team 24/7 and they can advise what to do. If it's an emergency phone 111. You are also advised to contact Community and Public on (03) 364 1777 and keep any leftover shellfish in case it can be tested." says Dr Williams.

Monitoring of toxin levels will continue and any changes will be communicated accordingly.

For more information:

NOTE: Cooking shellfish does not remove the toxin

Media queries can be directed to Canterbury DHB Media Liaison Amy Milne on 027 502 7523, or .

Page last reviewed: 03 November 2016
Contact Us
Image of a Phone By Phone
Image of an Email sign By Email

For a full list of the convenient ways that you can contact us, refer to the Contact Us page