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fluoridation - another issue that never seems to go away

Back in 2006 Hamilton held a referendum on the issue of whether or not the city's water supply should continue to be fluoridated. (We even held a Cafe Scientifique about it.) At that time 38% of eligible voters returned voting papers, & 70% of those voters wanted fluoride retained in our water. So I had a feeling of deja vu when I saw in Friday night's paper that there is a move afoot among some councillors to have fluoride removed.

There are several things that concern me here. One is that councillors should want to vote on this, rather than hold another referendum, given the fairly solid majority in the previous vote. Another is that the councillor who brought this issue up feels that if a ratepayer referendum should be held, it should be in the absence of any additional information from either side in the debate. (And this is very much presented as a black-&-white question.) How then are ratepayers to make an informed decision? Very few people will have kept any material provided last time, & with the city's population growth there will certainly be people here now for whom this will all be new. It's a bit specious to argue that because both sides provided so much information last time, there should be none this time round. Especially because (as you'll see if you read on) the question is most definitely not black-&-white!

And it's all very well to say that "even 'blind Freddy' recongised it was a matter of when, not if, and [Cr Macpherson] felt the time had come." Why? What made him come to this decision? What new data does he have, that weren't presented to the population last time? One can only hope that we are not seeing the result of the old 'arguments' that the populace is drinking an industrial poison, or drinking acid... (though I won't be surprised if these make it to the press again shortly).

Yes, there are some interesting & necessary discussions to be held around the fluoridation issue. One - a social & ethical question - is to do with mass medicalisation of the population - treating everyone to minimise harm to a vulnerable sector of that population. (Vaccination would be another example of this.) It's for this reason that I feel the local council should not be deciding the issue - on way or the other - without first holding a public referendum. Another - the one I'm more interested in here - is to do with some of the scare tactics associated with the 'debate', the ones I mentioned above. And these seem to hinge on a misunderstanding of some basic scientific concepts. The fluoride that's added to our city water supply does come from fluorosilicic acid, and this is a by-product of the fertiliser industry. But - & this is a big but - the quantities necessary to fluoridate water are miniscule: Hamiltonians are not drinking 'an industrial poison'. And nor are they 'drinking acid' (another claim I heard last time round). As for the fluoride ions themselves - fluoride is fluoride, regardless of its source. There is no chemical distinction between fluoride from a 'natural' source (weathered from rocks, for example) and the 'artificial' source used in treating town supply water.

What is important is concentration - as our original Cafe handout saysany discussion about benefits or toxicity needs to specify the concentrations involved. Typically fluoride concentrations in domestic water supplies are around 1 part per million (1 ppm, or 1 mg per litre). One litre of drinking water will contain about 0.001 g of fluoride anion. And interestingly, analysis of Waikato River water before treatment shows around 0.95 ppm fluoride. During normal flocculaton treatment, fluoride concentrations are reduced to around 0.2 ppm, so lfuoride is added to drinking water to a target level of around 0.8 ppm, as recommended by WHO guidelines - this is slightly less than the original natural level!

But questions do remain about the relative benefits of fluoridating water over the use of, say, fluoride gels and toothpastes. And it would be good to see some solid discussion of this in the local press, before we get to the point of having another go at this decision. As a starting point I'd recommend the Cochrane Library, which has reviews of the effectiveness of fluoridated toothpastes (a 'yes') and other topical treatments have been proposed as alternatives to fluoridation of water supply. (One of the underlying reasons for fluoridation is that it offers protection from dental caries to those who, for whatever reason, can't afford or don't use these alternatives.) Just in passing, I see that they're also initiating a review to examine the possibility of links between topical applications of fluoride & the condition known as dental fluorosis.

Anyway - if we are going to revisit this again - please can we manage an informed, and a reasonable, debate?

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11 Comments

It's about time this archaic and ineffective practice was put to bed.
There is no evidence whatsoever that supplementing fluoride into a town's water supply has a positive effect against dental decay. Absolutely none.
And it costs an arm and a leg to remove the stuff from my household supply.
Most European countries and Japan stopped this stupid practice years ago. I think that's saying something.
I don't think a referendum is the way to go because the DHB has far too much political clout and uses their superior financial power to sway opinion through a campaign of 'fear' (we must all have fluoride or our children's teeth will rot).
Then you have newspaper editors who sway the debate according to their own opinion.
Just take the stuff out and all the fuss will be gone.
Educate people to do the right thing (brush their teeth, eat the right foods) and we will all be happier and healthier.
Whatever, do NOT force people, restrict their freedoms or dictate what they can and can't do.
We all pay for clean water through our rates. If I want to supplement it, then let ME do it.
If the govt really cared about our health, perhaps they'd be supplementing our water with magnesium. Fluoride has no function in the body whatsoever, other than to act as a toxin.

It is stated above that one of the interesting and necessary discussions to be held around the fluoridation issue is on the social and ethical question of mass medication.
The best short contribution to this discussion is from Dr Arvid Carlsson, Nobel Laureate in Medicine (2000) who says: “Fluoridation is against all modern principles of pharmacology. It’s obsolete. I don’t think anybody, not a single dentist, would bring up this question in Sweden anymore.”
There is also a wealth of accumulated science concluding that fluoride doesn’t work for dental health by swallowing it and that using it topically as a varnish or in toothpaste is the only viable option. There are also known health risks of fluoridation especially for infants, those with chronic kidney disease and various allergies among others.
In continuing to assert that there are years of research throughout the world showing that community water fluoridation is a proven public health measure district health boards and other agencies grossly misinform communities.
A systematic review of public water fluoridation undertaken by researchers in the UK National Health Service, the universities of York, Wales and Leicester and the Department of Epidemiology and Public Health searched 25 electronic databases (with no language restrictions) and the world-wide-web. Relevant journals and indices were hand searched and attempts were made to contact authors for further information. This project is known as ‘The York Review’.
The review was exceptional in this field in that it was conducted by an independent group to the highest international scientific standards. A summary has been published in the British Medical Journal.
Inclusion criteria were assessed independently by at least two reviewers. Extraction of data from and validity assessment of included studies was independently performed by two reviewers, and checked by a third reviewer. Disagreements were resolved through consensus.
The best available evidence forthcoming suggested that fluoridation of drinking water supplies does slightly reduce caries prevalence, both as measured by the proportion of children who are caries free and the mean change in the decayed, missing or filled teeth index score but the review says that estimates of effect could be biased due to poor adjustment for the effects of potential confounding factors.
The studies reviewed were not only of moderate quality but also of limited quantity and the degree to which caries is reduced was not clear from the data available. Not one study of grade A status, that is one of “high quality, bias unlikely”, was found.
Four years after publication, so incensed was he at misrepresentations of its findings by British dental and medical establishments, that Prof Trevor Sheldon of York University, as former chair of the review advisory group responded with an open letter to correct some of their errors.
He stated:
1. Whilst there is evidence that water fluoridation is effective at reducing caries, the quality of the studies was generally moderate and the size of the estimated benefit far from ‘massive’.
2. The review found water fluoridation to be significantly associated with high levels of dental fluorosis which was not characterised as ‘just a cosmetic issue’.
3. The review did not show water fluoridation to be safe.
4. There was little evidence to show that water fluoridation has reduced social inequalities in dental health.
5. The review could come to no conclusion as to the cost-effectiveness of water fluoridation or whether there are different effects between natural or artificial fluoridation.
6. Probably because of the rigour with which this review was conducted, these findings are more cautious and less conclusive than in most previous reviews.
7. The review team was surprised that in spite of the large number of studies carried out over several decades there is a dearth of reliable evidence with which to inform policy.
My reading indicates that in the intervening eight years since the York Review there is now considerable evidence supporting a highly precautionary approach to fluoridation which should drive policy by both health agencies and local governments.
Health authorities also ignore World Health Organisation data unequivocally showing that dental health is improving around the world whether communities are fluoridated or not.

I knew there was a reason I never wote about this issue.

*Wrote*, darn these poor typing skills.

In response to the Café Scientifique pdf:

Is there a chemical basis for fluoride protection of teeth from decay?

Although fluorapatite is harder and supposedly more resistant to acid attack than hydroxyapatite, all major large scale studies show there is no difference in tooth decay rates once the average one year delay in tooth eruption caused by fluoridation has become insignificant –about age 12 to 15. The closest to home is Armfield and Spencer, Australia, 2004: zero benefit at age 12.

Does the source make a difference?

The only study on the dissociation of silicofluorides is Crosby 1969. Two analytical methods showed an 87% and 95% dissociation in Ph-neutral water. So some slilicofluoride ion remains. This is a ‘weak electrolyte’, so will tend to revert to the molecular form in the acid conditions in the stomach. Also, when ions are in a mixture in solution they tend react synergistically; not independently.
So the source of fluoride does make a chemical difference.
Three studies also show that silicofluorides have a different effect on the body than sodium fluoride. 1) Westendorf 1975 showed SiFs inhibit acetylcholinesterase but sodium fluoride does not. 2) Masters and Coplan in 1999 showed SiFs cause an increased uptake of dietary and environmental lead, while Sodium Fluoride does not. 3) The 1999 research was confirmed by a larger group in 2007.
So the type of fluoride does make a biological difference to humans.

Regarding the contamination of fluoridating agents by heavy metals: one of these is lead. The Maximum Contaminant Level Goal of Lead is zero. Adding any Lead to the drinking water unnecessarily is therefore unjustifiable. The contaminant level allowed is 395mg/kg of fluoridating agent.

What is the importance of concentration?

Firstly, the paper confuses concentration with dose. Concentration is irrelevant unless it is high enough to result in molecular HF being present. It is the total dose that is important. The so-called optimal dose determined in the 1930s and 40s by Dean is already exceeded today without fluoridated water. No “optimal dose” has ever been determined for infants, only older children and adults.
The level of fluoride in the Waikato river is not natural fluoride – it is pollution from agricultural run-off. The Hamilton Council has previously confirmed that after heavy rain the levels exceed 1ppm and the fluoridation plant shuts down. Hamilton citizens are overdosed with fluoride during these times.
The natural level of fluoride in NZ water ranges from about 0.01 ppm to 0.3ppm, but is usually less than 0.2ppm. This level of calcium fluoride is the maximum generally considered safe outside the fluoridation-promotion sector.

Does added fluoride improve dental health?

It is internationally accepted (since Featherstone, 1999) that any benefit accruing from fluoride is by topical application; not by swallowing. This misbelieve arose because in the 1930s we had come to understand the role of essential nutrients, vitamins etc. and it was assumed that fluoride entered teeth in the same way. This proved incorrect. Note that Fluoride is not an essential nutrient according to international medical authorities.
Five pieces of research show that the concentration of fluoride must be at least 2ppm to have topical benefit. This may explain why the original towns observed in the USA supposedly had less tooth decay (note there is considerable contention whether this was so, or just an urban myth). These communities had 2.5ppm fluoride or more, above the threshold for topical benefit.

Does fluoride in drinking water cause hazardous side effects

This depends on the total daily intake (dose) and general health of the individual. There is also ample evidence, including medical certification, that some individuals have a chemical intolerance to fluoride. The US National Research Council concluded that at 1ppm there are a number of at-risk subsets of the population. Around the world there are areas where de-fluoridation plants are in operation, due to observed adverse health effects of fluoride. This includes India, which leads the world in fluoride research regarding adverse health effects, Italy, and Southeast Asia. UNICEF has described fluoride as the single greatest waster-borne threat to human health on the planet.
Since 1995 in particular there have been numerous studies showing adverse health effects from fluoride. Fluoridealert.org and fannz.org.nz list some of these. As the UK York Review observed in 2000, fluoridation promoters never conduct studies on adverse effects: they only study effects on teeth, trying to prove benefit – which has alluded them for 60 years now.

Reading Alison Campbell's comments reminds me why I hold academia in only moderate regard (at best).

Firstly, she regards the Waikato Times news article as some sort of research report that accurately records all that was said in both the brief discussion on fluoridisation at Council and in subsequent interviews - it wasn't, and at best was only a snpashot of a few aspects of the issue, published as a major piece simply because the newspaper had little hard news that day.

Secondly, she did not bother to check any aspect of the Times article with me, the Councillor named in the Times & in her blog - that she hasn't done, while raving on herself, betrays her own partisan stance on the issue (which would be fine if she would only admit it and quit moralising about democracy, etc.).

What I actually proposed was that Council hold a debate on fluoridisation of Hamilton's water supply in about a month. I made a comment that I didn't think it was necessary for COUNCILLORS to conduct another referendum in order to comprehend the issues - they have already been done to death with us, and I believe we are sufficiently informed by all parties to make a decision which may or may not go the way I would like it to go. Four Councillors supported that view, while another two wanted to hold that debate in 8 month's time. Another Councillor agreed with my views on fluoridisation, but wanted the protection of a referendum (as he does for most big issues, because he's a little uncomfortable with making his own mind up on occasions).

What surprised me was only that a majority of Councilllors, in one way or another, questioned the need to fluoridisation of Hamilton's water supply. That the majority seem to now be inching towards this decision, after hearing the myriad arguments for and against, seems to me to be quite instructive, and the Waikato Times certainly were interested by that aspect.

If Ms Campbell is so keen on a referendum, she would be able to initiate a petition calling for one - as the Councillor who 10 years ago moved for this element of democracy to be restored to Council policy, I can safely say I want her to have this chance - churning out an academic blog might earn you brownie points on Hillcrest hill, but doesn't really impinge on the minds of the residents that a referendum might.

As to my colleague Cr Blind Freddy, and his view that the removal of fluoride is inevitable, you only need to look at the numbers of jurisdictions that do and don't have it added to their water supply, and the changing trends there. Personally I also look to the increasingly frenzied justifications for it by the white coat brigade in our DHBs and the Ministry of Health. After all, the same people promoted & endorsed the aerial spraying of half the city in the failed hunt for a solitary male moth - an exercise in mass medication that was (conveniently) later criticised by other parts of officialdom.

However I don't see conspiracies everywhere, though I do see entrenched views expressed by the elite & their mouthpieces, and believe - where there is some evidence - that these views can and should be challenged. And whenever they are challenged, it is quite instructive to see which forces gather to howl down the challengers!

Hi Mark - & also Ross & Mathew (I hope you don't mind me bundling you all together!) - thank you for taking the time to write in, & also for presenting such reasoned & evidence-based responses. I really do appreciate this, even though I suspect we may not always see eye to eye on some of the issues surrounding fluoridation.

I had heard that the EU is requiring non-fluoridated water for processing foods (although this is not the same thing as banning it from drinking water). I do wonder if this could be related to the fact that several European countries now use fluoridated salt...

I'm a bit surprised that F is regarded as the single greatest water-borne threat to human health. Do you have a reference for that? - it would be good to hear more about it. The reason I wonder is that arsenic in drinking water is present in lethal levels in ground-water in extensive areas of Bangladesh, & also South America - in fact I wrote about that in a previous blog post ("Arsenic & Old Mummies").

Agricultural run-off does contribute to F levels in the Waikato River after rain, as fluoride is present in superphosphate. But I've checked with colleagues who've studied the river chemistry & the base level of F is from geothermal waters, so the river could be said to be naturally fluoridated. (They also tell me that the lead levels you quote are not the case in NZ, where lead is not detectable by any technique.)

Thanks again for writing - this is the sort of discussion that we do need to be having :-)

PS I see that Westendorf (1975) comments that fluoride in drinking water doesn't have its effect as on its initial passage through the mouth, but is absorbed in the gut & expressed in saliva - it would sit around in the mouth & presumably have almost a topical effect. He also noted that F- does inhibit acetylcholinesterase, but at concentrations that are 'extremely toxic & even lethal in vivo', which is a very long way indeed from the concentrations found in drinking water. Similarly the observed effects on 'erythrocyte ghost' permeability occurred at F- concentrations much higher than those found in town supply water. ('Erythrocyte ghosts' are the empty membranes of red blood cells, formed when the cells are burst - & lose their contents - when placed in distilled water.)

Dave - from the tone of your reply I can only assume that I've inadvertently touched a nerve. I'd like to make a few points in reply.

I'm not 'moralising' about democracy. If you read my blog you'll find it was originally intended for senior bio students (although I know it has a much wider readership than that). One of the topics they study is a 'current/controversial' biological issue, & as part of that they need to think about social & ethical aspects of the issue. The idea of mass medicalisation of a population is one of these, & worthy of reasoned consideration. Similarly, because different people have quite different views on this issue, it is indeed one where there's a need for a healthy democratic debate - & not just within the council chambers.

I comment reasonably often on the way that various issues are presented in the press, & of course I'm aware that this presentation may not always be accurate. But I'd also like to say that for many of us in Hamilton, we rely on the press for coverage of Council discussions. If you consider that the coverage of this particular discussion was not accurate, perhaps this is something to take up with the editor of the Waikato Times.

I would also say that ad hominem arguments do little to advance your case. The other commentators here & I may, or may not, agree on some of the points that are raised, but their comments are evidence-based & as such give a basis for a good discussion, which I hope we'll continue to have.

The MoH and WDHB are not interested in allowing a robust sensible debate on this issue. They threw hundreds of thousands of dollars during the last referendum to dominate and silence opposition.
Water fluoridation is just wrong. The Precautionary Principle should tell you that. There are stronger arguments for adding Vitamin C to drinking water - what hoops would I have to jump through to get that passed? And yet somehow it has become acceptable to add a toxic waste byproduct that has never been subjected to safety trials on human beings, to our drinking water.
The only right thing is to look at the causes of tooth decay and address those and we all know what they are:
1)poor diet
2)poor dental hygiene
3) poor dental treatment intervention
It is no use whining that changing the diet is too hard - that argument has lead to epidemic rates of obesity and diabetes - thats the real social cost of not doing the right thing at the right time.
The WDHB deliberately withheld the results of their dental survey until a week after the referendum because it showed that after 40 years of forced mass medication, teeth were worse than in unfluoridated areas.
Now they have just confessed that the dental service is "antiquated" and have decided to finally beef it up - just like we had asked them to do years ago when it was obvious that small holes were being allowed to develop into big holes because of lack of timely intervention not because of lack of fluoride.
Arguments about the dilution are irrelevant - Hamilton has had at least 3 spillages to my knowledge and Brisbane had a big spill just last month with 20 times the recommended dose - and noone was told for two weeks.
Dave MacPherson is a hero in my eyes - at last we have a public official willing to say it how it is. I am still waiting for all the dentists I know who disagree with the practice to come out and be honest - they won't because they fear the repercussions of the Dental Association. Does anyone really believe this is a good idea? I mean, anyone who knows anything about it?
My children all have dental fluorosis - the biomarker for fluoride poisoning. I hope this happens to the kids of everyone who supports this unethical practice. That is the only thing that will make them stop and think.
We were not consulted when they put it in - let them take it out without consultation. Lets start at the beginning and require them to jump through the same hoops as if it was Vitamin C or any other product that is actually proven to be beneficial.

A couple of comments in reply. One is that the 'toxic waste' gambit doesn't work on a science-based forum. As I've said elsewhere, concentration is all-important. True, if you ingest large quanitities of fluorosilicic acid you will be a very sick puppy. The same will happen if you ingest large quanitites of vitamin A, vitamin E, water... the list is quite extensive. In the case of water fluoridation the concentration of fluoride is a very long way below toxic levels. Talking about 'spills' of fluoride is a straw man in this context. I agree that 'spills' are not good, but they are quite distinct from the normal treatment of water that is the focus here.

Dental fluorosis is also a bit of a red herring as drinking fluoridated water is by no means the only cause. Excessive ingestion of fluoride toothpaste, or over-zealous applications of fluoride gels, will deliver the same result.

And finally: the population at large may not have been consulted when fluoride was first added to Hamilton's water, but it has certainly been consulted since, most recently in the 2006 referendum.

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