Health authorities have upgraded their shellfish and fishing warning for the Swan River, which now extends from Pelican Point to West Swan Road Bridge in Guildford.
The WA Health Department said ongoing monitoring of the Swan River now showed increased levels of the potentially toxic microscopic algae Alexandrium spp in a wider area.
The department is advising people not to eat fish, crabs or shellfish collected from the Swan River, extending from Pelican Point and Matilda Bay, upstream to the West Swan Road Bridge, Guildford. This area includes the commonly known areas of Matilda Bay, Perth Waters, Elizabeth Quay, Barrack Street Jetty, Claisebrook Cove and Ascot Waters.
Acting Environmental Health executive director Dr Michael Lindsay said that ingestion of toxins produced by the detected microscopic algae could produce a type of poisoning known as paralytic shellfish poisoning.
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READ NOW"These algae, which are not visible to the naked eye, can produce a toxin which could be absorbed by filter feeding shellfish and potentially consumed by crabs and finfish to a lesser extent,” he said.
“It is important to note that cooking will not destroy these toxins.”
People who consume wild shellfish, crabs or fish collected from this affected Swan River area may experience symptoms including, tingling or numbness of the lips, prickliness of the fingertips and toes, nausea or vomiting, impaired balance, dizziness, slurred speech, double vision, weakness, difficulty in swallowing or breathing, loss of fluids and diarrhoea.
In severe cases PSP can cause muscular paralysis in people who consume affected shellfish, crabs or fish.
Dr Lindsay said that anyone who had consumed shellfish, crabs or fish collected from the Swan River and experienced any of the symptoms should seek urgent medical attention, particularly if they felt any respiratory distress.
“Do not discard uneaten portions of mussels or other shellfish as these may assist with determining a likely cause of any symptoms,” he said.
Shellfish includes oysters, mussels, clams, pipis, scallops, cockles and razor clams.