People have been told to avoid the water at Lake Ngangana. Photo: Supplied / Te Whatu Ora
A health warning has been issued for a Taranaki lake after the emergence of a dense bloom of potentially toxic blue-green algae.
The Taranaki Regional Council has erected signs at Lake Ngangana in Waitara warning people to avoid contact with the water.
Blue-green algae can cause asthma and hayfever attacks, upset stomachs, skin rashes, headaches and neurological effects.
Algae blooming at Lake Ngangana. Photo: Supplied / Te Whatu Ora
Children and dogs are at particularly risk.
Te Whatu Ora Medical Officer of Health for Taranaki Dr Neil de Wet said the regional council issued the health warning based on water test results and visual observations.
Any activity which resulted in contact with the lake water should be avoided, he said.
"Contact with water affected by blue-green algae blooms can cause asthma and hay fever attacks in some individuals.
"Contact with the blue-green algae can also cause skin rashes, stomach upsets, and in some cases neurological effects such as tingling around the mouth, headaches, breathing difficulties and visual problems," he said.
"Algal mats and scum may accumulate along the shoreline of the lake and so it's especially important that parents ensure that children avoid contact with these as they may be toxic."
Dogs were particularly at risk and should also be kept away from the shoreline.
Elsewhere in New Zealand there have been reported deaths of dogs that have eaten toxic algae on shorelines.
Dr de Wet advised that it was always a good idea to keep an eye out for signs of algal blooms if using lakes in Taranaki and report any concerns to the local council.
"Algal blooms can develop rapidly and unpredictably and can sometimes produce toxins that are harmful for people as well as animals.
"If the water looks discoloured, has an unusual smell, or has green or brown particles floating in it then it is best to avoid contact with it."
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