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Twofold Bay area algal toxin alert - update

29 Oct 2016

NSW DPI advises people not to consume shellfish collected or caught from Twofold Bay, due to the risk of Paralytic Shellfish Poisoning (PSP). Paralytic shellfish toxins are produced by certain toxic algae species. Alexandrium fundyense have recently been detected in the waters of Twofold Bay.

Shellfish taken from this area should not be eaten. Cooking does not destroy the toxins. The NSW Food Authority has confirmed that toxin levels detected in shellfish from Twofold Bay have increased.

Lobsters and abalone are also known to accumulate the toxin in the viscera (tomalley) of rock lobsters and the viscera and mantle of abalone. It is recommended that consumption of viscera from crustaceans and gastropods captured from Twofold Bay is avoided. The mantle of abalone should either be removed or scrubbed clean to remove any pigment. As a precaution people should also avoid consuming sea urchins from the area.

Symptoms of PSP occur between 15 minutes to 12 hours after consuming contaminated shellfish. Symptoms usually begin with tingling and numbness around the mouth and face, progressing to the extremities followed by dizziness, nausea, headache, vomiting, vertigo, a floating sensation, weakness, and muscular unco ordination. In severe cases paralysis, difficulty in breathing leading to respiratory failure, and even death can occur. Anyone experiencing these symptoms after eating seafood from or near the affected area should seek immediate medical attention. Paralytic Shellfish Poisoning is rare, but it is important that people follow this advice to avoid getting sick.

The NSW Food Authority is monitoring the situation and advises to only eat shellfish harvested under a recognised commercial program. Commercial shellfish harvest in the area has ceased and product in the market place is not affected.

If any health effects are experienced from contact with water affected by algal blooms, medical advice should be promptly sought.

This media alert only reports algal blooms that have been brought to the attention of NSW DPI.

Algal blooms may be present in other areas. Algal blooms can occur anywhere along the coast and are normally the result of the surge of nutrient rich deep ocean water onto the continental shelf, and can often be seen after rainfall events in estuaries and in river mouths. Some of these algae produce harmful toxins that can build up in marine shellfish.

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