Children and dogs are warned to stay away from Lake Rotorua’s Holdens Bay as a new health warning has been issued.

The Lake Rotorua warning was issued tonight after testing for cyanobacteria in water samples.

Dr Lynne Lane, medical officer of health for Toi Te Ora Public Health warned that algal mats and scum could accumulate along the shoreline “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 algae on shorelines, she said.

“The bloom at Holdens Bay at Lake Rotorua is likely to be of blue-green algae which can be toxic and so it is important to avoid any activity which results in contact with the lake water.”

Contact with water affected by blooms of blue-green algae can cause asthma and hayfever 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.

Meanwhile, the health warning that has been in place at Lake Rotoiti’s Okawa Bay has now been lifted after Bay of Plenty Regional Council testing and observations indicate the algal bloom in the area had now cleared.

However, a warning for Lake Rotoiti at the Okere Arm remains in place.

Dr Lane said: “People should avoid any activity which results in contact with the water in the Okere Arm of Lake Rotoiti.”

Signage advising potential lake users about algal blooms is erected at sites along the shore of the bay.

Lane warned people to keep an eye out for signs of algal blooms if using lakes in the area.

“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.”

Up-to-date information on health warnings for the Bay of Plenty and Lakes districts is available through these channels:

• Phone: 0800 221 555
• Website: www.toiteora.govt.nz/health-warnings
• More information: www.toiteora.govt.nz/public/recreational-water
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