Queensland Premier Anna Bligh says a malfunction which pumped a surge of fluoride 20 times higher than recommended levels through water pipes in north Brisbane will not stop the statewide rollout of fluoride.
The malfunction happened two weeks ago while the North Pine water treatment plant was shut for routine maintenance but did not pose a health risk.
The fluoride system, which should have shut down automatically, continued to operate for a short time.
When the plant was brought back on line, a higher than normal concentration of fluoride was flushed for three hours through the pipes servicing the Warner and Brendale areas.
Water and health authorities completed tests on Tuesday and briefed the premier on Wednesday night.
“While I am very concerned about this incident, it does not concern me in relation to the benefits of fluoride in our drinking system,” the premier said, announcing an independent investigation into the incident.
“Our plants treat our water for a range of safety purposes, so I want to understand what happened in this case.
“But it does not for one minute shake my confidence that fluoride is one of the most significant public health leaps forward of the last century.”
Ms Bligh said the incident was unprecedented at any other fluoride treatment plant in Australia.
“There will be a thorough investigation of this issue,” she said.
Chief health officer Dr Jeannette Young said the amount of fluoride that passed through the pipes over a three hour period was “of no health concern at all”.
“I’m confident the risk of anyone having suffered any adverse health outcome is remote – if indeed not zero,” she said.
The concentration of fluoride was 30 to 31 milligrams per litre, while the regulated maximum is 1.5 milligrams per litre.
Dr Young said for there to be a health risk the levels would have to be much higher and for much longer than three hours.
“It’s a high level in terms of what’s provided in the water but it’s a low level in terms of any risk,” she said.
Ms Bligh said Mark Pascoe, CEO of the International Water Centre based in Brisbane, will run the investigation.
“As an immediate precaution when any water treatment plants are shut down for normal maintenance, there will be a manual shutdown of the fluoride dosing equipment,” she said.