Toxin found in shellfish

People are being warned not to eat shellfish from Hokianga and Kaipara Harbours.

People are being warned not to collect or eat shellfish from the west coast between the Kaipara and Hokianga harbours after a toxin has been found in samples from the area.

Routine testing by Ministry of Primary Industries has found paralytic shellfish poisoning (PSP) toxins above the regulatory level in shellfish on that coastal stretch.

There have been no reports of anyone becoming sick from eating the toxic shellfish during this latest episode or in those of previous years.

The chemicals that cause toxic shellfish poisoning are produced by certain species of toxic algae, and are released into the shellfish when they eat the algae. Freshly gathered mussels, oysters, tuatua, pipi, toheroa, cockles, scallops, catseyes, kina and all other bivalve shellfish should be off the menu until the warning is lifted. Paua, crab and crayfish may still be eaten if the gut has been completely removed prior to cooking.

Northland District Health Board's public health unit said the symptoms of PSP include numbness and tingling around the mouth, face or extremities; difficulty swallowing or breathing; dizziness; double vision; nausea and vomiting. In severe cases, paralysis and respiratory failure can occur within 12 hours of eating the shellfish.

"Cooking the shellfish does not remove the toxin," Northland medical officer of health Dr Clair Mills said.

Since 2008, there have been four warnings about PSP on Northland's west coast; the last was in January 2013.

People with queries about shellfish safety can call Whangarei Hospital on 09 430 4100 and request the on-call health protection officer. Anyone who becomes ill after eating shellfish should see a doctor, phone Healthline on 0800 611 116 or in an emergency phone 111.