Fluoride will be an election issue in the upcoming WA poll.

Candidates for the far north WA seat of Kimberley are backing candidates that oppose the introduction of fluoride to Kununurra's drinking water.

Kununurra's drinking water will be fluoridated next year, but Liberal candidate Warren Greatorex and Labor MP Josie Farrer have both gone against their own parties’ policies and the advice of the medical world to allow the community to decide.

Mr Greatorex is against water fluoridation.

“I have educated myself on this, there is a bit of science behind it, but from what I can gather it tends to hinder it more than benefit it,” he said.

“But it comes back to the choice of the people.”

WA Health Minister John Day, a former dentist, says 92 per cent of the state has fluoridated water, and that scientific evidence continues to support its health benefits.

“I know there's a small vocal group in the community who are opposed to important public health measures, whether it be fluoridation or vaccination programs,” he said.

“But their comments are not based on any reputable science.”

Ms Farrer helped work on a petition opposing water fluoridation, which attracted 771 signatures, but the Labor party’s health spokesperson Roger Cook says the party does not support the anti-fluoride movement.

“I'll let Josie speak for herself. I can tell you that the WA Labor Party stands for a strong fluoridation program in Western Australia,” Mr Cook said.

“This stuff should be driven by the science, not populist political positioning by local Liberal Party candidates.”

The Australian Medical Association says there is no good argument against water fluoridation as a public health measure.

“There's a tidal wave of evidence that shows that fluoridation is safe and effective,” WA vice-president Dr Mark Duncan-Smith said.

“If it is good for the greater part of the community, then it is possible that some of the rights of the individuals may have to be foregone.”