Warning: Toxic Algae bloom returns early
5 May 2004
Health Warning: Winter Toxic Algae bloom returns early to Hawke’s Bay – entire coastline closed for shellfish collection
Hawke's Bay District Health Board today issued a public warning advising people not to eat shellfish harvested from the Hawke's Bay coastline between Whareongaonga (approximately 22km north of Mahia Peninsula, and Cape Turnagain in the south, due to levels of Paralytic Shellfish Poisoning (PSP) toxin above the New Zealand Food Safety Authority's safe health limit, being found in shellfish.
Results from mussels sampled from Portland Island, Mahia and Waimarama Beach south of Cape Kidnappers on the 2nd of May have returned today with levels of 106 and 129 micrograms of toxin per 100 grams of flesh respectively. This is above the New Zealand Food Safety Authority’s level at which an area is closed for shellfish collection - being 80 micrograms per 100 grams of flesh.
Water samples taken at the same time as the shellfish samples from both sites indicate that the toxic algae Gymnodinium catenatum appears to be the algae responsible for the PSP toxin levels in the shellfish. This is the same algae that has caused closures of the Hawke’s Bay coastline over the past three winters.
Further samples from all areas will continue to be collected, and the public will be advised of results.
Kina, mussels, toheroa, pipis, tuatua, oysters and cockles in affected areas should not be eaten.
Paua, 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. Cooking affected shellfish does not remove the toxin.
Fish, such as snapper, gurnard, and terakihi are not affected by the algae and are still safe to eat.
It needs to be stressed that anyone eating toxic shellfish in closed areas could be at risk of serious illness.
Symptoms of Paralytic Shellfish Poisoning can occur within 12 hours of eating affected seafood and can include: Numbness and a tingling (prickly feeling) around the mouth, face, and extremities first. Difficulty swallowing, or breathing. Headache, dizziness, and double vision.
Severe cases may suffer respiratory arrest resulting in death if medical treatment is not immediately available.
“We advise the public not to risk their health by consuming shellfish when a closure is on. We have had anecdotal reports of people consuming shellfish during closures and these people are taking risks with their health. Levels of the toxin in shellfish can fluctuate markedly up, or down, very quickly depending on the level of the toxic algae in the water. The closure limit is designed to take such factors into account.”
If anyone becomes ill after eating shellfish from any Hawke’s Bay area (not just the closed area) they should contact a doctor immediately and also advise the Public Health Unit on (06) 878 1329.
The Public Health Unit is sending information to doctors, community groups and other authorities in the region. Staff are currently putting up warning signs at seafood collection sites, and boat-launching sites in the affected closed area. Anyone wanting further information can phone the Hawke's Bay District Health Board's Toxic Shellfish Information Line on (06) 878-1329. There is a pre-recorded message giving the latest sampling results, the status of the closure, and a facility for people to leave their contact details and a message if required.
Information on the closure will be posted and updated on Hawke’s Bay District Health Board’s web site www.healthinhawkesbay.co.nz in the Public Health Unit’s area of the site.