An international trio of academics has lent substance to the sometimes-hysterical lobby against fluoridated water supplies with their book The Case Against Fluoride.
One of the three, Paul Connett, former Professor Emeritus of Environmental Chemistry and Toxicology at St Lawrence University in New York, visited Upper Hutt's Orongomai Marae on Monday to promote his cause and the book.
A Ministry of Health spokeswoman said Professor Connett has spoken of the perceived risks of water fluoridation, while ignoring the public consequences of dental decay.
Professor Connett's co-writers were James Beck, Professor Emeritus of Medical Biophysics at the University of Calgary, and also a doctor of medicine, and Spedding Micklem, Professor Emeritus in the School of Biological Sciences at the University of Edinburgh.
Professor Connett said he never wanted to get involved in the fluoride lobby, but felt compelled to after his wife pressured him into reviewing research into the subject.
He was teaching environmental chemistry and providing consulting services in waste management at the time.
``I certainly didn't need a third issue that would stigmatise me in the US, an issue that would paint me as looney-tunes,'' he said.
That was 15 years ago and he has been advocating against fluoridation of water supplies ever since.
He has four main arguments against public water fluoridation.
The demonstrable benefits from fluoridation of water supplies are very small, he said.
At age 12 the average child is better off by about one fifth of one tooth surface if they live in a community with fluoridated public water supplies compared with a child who does not.
"Teeth have been in the mouth for a shorter amount of time," he said.
They are therefore exposed to less sugar.
"The benefit is completely eliminated by a one-year delay of eruption of the tooth."
His second argument is that fluorides are demonstrably toxic, causing brittle bones in later life, elevated rates of cancers and some studies are now suggesting that, even at very low levels, ingested fluorides inevitably cause lowered IQ in populations which receive it.
A study in China led by Professor Quanyong Xiang published in 2010 found for every one part per million of fluoride in the blood, the average intelligence quotient (IQ) was lower by 0.59, Professor Connett said.
The third point is that compulsory mass medication is unethical.
Professor Connett said any doctor who administered a drug to a single patient without fully informing him of the likely effects, and monitoring those effects would inevitably be struck off for malpractice.
Furthermore, compulsory mass medication is poor medical practice, he said.
"Once you put medicine in people's water you can't control the dose you can control the concentration, but you can't control the dose, and you can't control who gets it."
How much any individual received would depend on how much they drank.
"The naturally-occurring level in mother's milk is 0.004 parts per million, which means a bottle-fed baby in a fluoridated community is getting 250 times more fluoride than a breastfed baby," Prof Connett said.
Ministry of Health chief dental officer Robyn Haisman said the ministry is aware of some dissenting opinions on the merits of fluoridation of drinking water, including those of Prof Connett.
However, the ministry regularly scans international literature to ensure its policy takes account of significant scientific findings.
"Professor Connett significantly downplays dental caries as a population disease and the real improvements that fluoridation has on the whole community, especially those most at risk of dental decay," she said.
"Dental caries affects 41 per cent of children aged two to 11 years in their primary teeth, 39 per cent of children aged five to 17 years in their permanent teeth and 77 per cent of the 18-to-24 years age group."
Results from the New Zealand Oral Health Survey, strongly support data from other recent studies that dental decay is an ongoing and progressive disease.
"Simply to say that it [water fluoridation] only prevents 0.6 of a tooth surface of decay is simplistic and misleading," Dr Haisman said.
"Fluoridation has an ongoing effect on reducing the impact from a disease which is progressive throughout life."
Prof Connett raises risks of fluoridation but fails to talk about the pain and suffering which will be caused through increase dental decay by removing water fluoridation, she said.
"Fluoridation is one of the most cost-effective ways to reduce dental decay in communities.
"The financial costs of treating dental disease are high, while the costs of water fluoridation are relatively low."
Upper Hutt regional councillor Paul Swain said the council has expertise in water treatment and distribution.
"It doesn't have expertise in oral health. For that we take guidance from the Ministry of Health.
"The current advice is that fluoride, dosed in accordance with the drinking water standards, is safe and effective," he said.
- Upper Hutt Leader
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