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Fluoridation: Open letter to Democrats for Social Credit

The only New Zealand political party opposing community water fluoridation relies on false information

The only political party in New Zealand campaigning against community water fluoridation is the Democrats for Social Credit. It is a minor party, nor represented in Parliament and of little influence. However, it does have connections with Fluoride Free NZ, the main anti-fluoride activist group, and its members have imposed anti-fluoridation policies on some groups they belong to. Two examples are Grey Power and the Hamilton Residents & Ratepayers Association – both of which presented anti-fluoride submissions to the recent parliamentary health committee hearings.

I wish to promote an open discussion with the Democrats for Social Credit about their anti-fluoridation policy so have sent them this Open Letter. If they are open to a good-faith discussion I am happy to provide space on this blog for an exchange of views on their policy.


David Trantor, Health Spokesperson for Democrats for Social Credit

Dear David Tranter,
Health Spokesman,
Democrats for Social Credit

You wrote an open letter to the Minister of Health critiquing the government’s policy on community water fluoridation (CWF) and posing some questions about dental health programmes, documented evidence relating to CWF and human rights aspects you consider relevant.

Here I take issue with some of your claims – particularly about dental health in Denmark and the scientific evidence supporting CWF. I believe the evidence does not support the anti-fluoridation policy of your party and your party should reconsider that policy.

If you believe my arguments here are mistaken or otherwise wish to defend the current anti-fluoride policy of your party I am open to a good-faith exchange of opinions and offer you the right of reply and the opportunity for a further discussion on this blog.

Natural fluoridation in Denmark

You point to the good dental health in Denmark and assert “they have never fluoridated their water.” This is true – but you ignore the fact that much of the Danish population benefits from natural levels of fluoride in their drinking water.

Unlike New Zealand parts of Denmark have drinking water fluoride concentrations similar to the optimum concentrations recommended for CWF. Map 1 from Kirkeskov et al., (2010) shows the distribution of different drinking water fluoride concentration ranges.  Map 2 shows the population distribution. We can see a significant fraction of the Danish population does have access to drinking water containing fluoride.

Map 1: Distribution of natural drinking water fluoride concentrations in Denmark. The town of Nexo is on the Baltic island of Bornholm – shown in the top left-hand rectangle.

Map 2: Population distribution in Denmark.

These natural levels of drinking water fluoride are beneficial to oral health in Denmark. Here is some data from Kirkeskov et al., (2010) illustrating this. The following graph compares the dental decay (numbers with more than 2 decayed, missing or filled teeth surfaces – dmfs) at various drinking water fluoride concentrations for 5 year-olds born in 1989 and 1999.

As we can see, the extent of decay declines with fluoride concentration.

There is a similar pattern for 15-year-olds born in 1979 and 1989. This figure shows the relative numbers with more than 2 decayed missing or filled teeth surfaces, DMFS, for 15-year-olds.

And the same pattern for 15-year-olds with more than 6 decayed, missing or filled tooth surfaces.

Danish dental health programmes

You refer to a “Nexux” programme and argue that this could be an alternative to CWF in New Zealand.

I think you are referring to the programme run in Nexo – a town on the east coast of the Baltic island of Bornholm, Denmark. It is a successful local dental health programme, but only one of several in Denmark. Nexo was in an area of very low socio-economic status and introduced a dental programme at the end of 1987 aimed at improving the dental health fo children.  Ekstrand & Christiansen, (2005) give this description of the programme:

“Since 1992, the program has been offered to children from the age of 8 months. It is based on three closely interrelated principles applied according to the individual child’s needs: (1) education of parents, children and adolescents in understanding dental caries as a localized disease, (2) intensive training in home-based plaque control and (3) early professional, non-operative intervention, including professional plaque removal, local application of 2% NaF and application of sealants. In the period when the children have erupting permanent first or second molars, the parents and children are instructed in using a tooth brushing technique specially designed for erupting molar teeth.”

As you can see it is a rather intensive programme and is not a Denmark-wide programme. It has been successful in Nexo, where 15-year-olds had DMFS (decayed, missing and filled tooth surfaces) values in 1986 (before introduction of the programme)  slightly higher than the Danish average. The equivalent values of DMFS for Nexo were the third lowest for all municipalities in 1993 and the lowest in 1999 (Ekstrand & Christiansen, 2005).

Elements of the Nexo programme will be used in other parts of Denmark, and in other countries. Especially where school-based programmes exist.

Incidentally, Map 1 indicates the concentration of natural fluoride in the drinking water on the island where Nexo is situated is similar to that recommended for community water fluoridation. Ekstrand et al., (2005) reports that the fluoride concentration in the Nexo drinking water is 0.8 mg/L.

Nexo is a complement to, not a substitute for, CWF

Each country and region adopt health programmes appropriate to their circumstance. In New Zealand, we have programmes which include some aspect of the Nexo programme or similar programmes like the ChildSmile programme in Scotland (see ChildSmile dental health – its pros and cons and ChildSmile – a complement, not an alternative, to fluoridation). For example the use of fluoride varnish treatments, especially in non-fluoridated areas.

New Zealand can learn from the experience of other countries and in practice, we may introduce some aspects of other programmes. But blanket transfer of full programmes is rare.

The important aspect, though, is none of these programmes is considered an alternative to fluoridation. They are considered as complementary to CWF, and not substitutes for CWF.  The Danish Dental Association has supported fluoridation for areas of low natural fluoride concentrations. Similarly, the British Dental Association in Scotland supports both ChildSmile and CWF and has publicly called for communities to move towards introducing water fluoridation.

In fact, we can consider that the programme used in Nexo (where the drinking water contains fluoride at 0.8 mg/L) actually complements the effect of natural community water fluoridation.

“Documented evidence”

You ask the Minister:

“Why do you ignore all the documented evidence against fluoridation instead of applying positive dental health policies such as the Denmark example?”

The “Denmark example” is dealt with above and it is not what you suggest. Similarly, I suggest the “documented evidence” you refer to really doesn’t give the viable argument “against fluoridation” you imply.

Unfortunately, you do not present any of this “documented evidence” for discussion. Perhaps, if you respond positively to my suggestion of a right of reply and an ongoing discussion, you can give this evidence.

“Informed consent”

You refer to the “H&D Commissioner’s Code of Rights” asserting that:

“no-one can be medicated without giving their informed consent” and “people have the right to give – or refuse – their INFORMED consent when fluoridation is applied to public water supplies?”

Well, I am all for people being properly informed and providing consent to the treatments used for their water supply. I see this as a democratic issue and I support democracy.

But you destroy your argument by suggesting fluoridation is a “medication” when it clearly is not – either legally or rationally. The legal argument was surely settled by the High Court decision in 2014 (see Corporate backers of anti-fluoride movement lose in NZ High Court) where Justice Rodney Hansen concluded:

“[80] In my view, fluoridation cannot be relevantly distinguished from the addition of chlorine or any other substance for the purpose of disinfecting drinking water, a process which itself may lead to the addition of contaminants as the water standards themselves assume. Both processes involve adding a chemical compound to the water. Both are undertaken for the prevention of disease. It is not material that one works by adding something to the water while the other achieves its purpose by taking unwanted organisms out.

[81] The addition of iodine to salt, folic acid to bread and the pasteurisation of milk are, in my view, equivalent interventions made to achieve public health benefits by means which could not be achieved nearly as effectively by medicating the populace individually. . . . All are intended to improve the health of the populace. But they do not, in my view, constitute medical treatment for the purpose of s 11″ [the relevant section of the NZBORA].”

Is scientific knowledge  really “one-sided” propaganda

You also weaken your argument by claiming:

“the one-sided propaganda used to support fluoridation is not informing people”

Describing objective scientific research and findings as “one-sided” simply displays your own bias – and willingness to discredit or ignore the science. Again, you do not give specific examples of the science you consider “one-sided propaganda” – hopefully, you will do so if you take up my offer of a right of reply and a continued discussion.

Democratic rights

You assert:

“when fluoridation is forced upon people it is nothing less than mass medication concerning which people have no opportunity to give – or refuse – their consent.”

The common anti-fluoride claim that people are having fluoridated water forced upon them always raises the picture in my mind of a person being held down and water being forced down their throat as in force-feeding.

Of course, that is ridiculous – for a number of reasons.

  • In New Zealand, there has usually been a democratic public consultation of some sort before the introduction of CWF – or even after its introduction. Local bodies have surveyed residents or used referenda. They have also used a consultation procedure relying on submissions from the public.The opportunity “to give – or refuse – their consent” has in most cases been far greater than for most decisions made by our representatives in this democracy of ours. Some voters find it annoying when asked for such consent (preferring their representatives decide) but I firmly believe it important to include the public in controversial decisions – even where the controversy results from scaremongering rather than facts (as it does with CWF).
  • There are alternatives for the minority. This means that democratic decisions made by a community can actually be a win-win situation. The majority get the social policy they want and have voted for. the minority have access to alternatives. In fact, most anti-fluoride activists already use alternatives – they filter their tap water or source a different supply. Some cities already provide “fluoride-free” water sources to help this. Sometimes I think the real motivation of these ideologically driven activists is to deny this social health policy to others rather than any real concern they have for their own access to water.
  • Some activists will acknowledge there is no evidence of any harmful side effects from CWF but invoke a “precautionary principle” to argue against it. They should be mollified by the fact that CWF is one of the most extensively researched topics. In a sense, we must thank the ideologically and commercially motivated anti-fluoride campaigners for this. Their activity is rarely successful in preventing CWF or fooling most of the public. But it does mean that researcher keep an eye on the arguments and are continually checking them out.

Conclusion

David, I believe you are mistaken, or misinformed, about the dental health programmes in Denmark. You ignore completely the availability of effective natural levels of fluoride in much of Denmark’s drinking water and seem unaware of the nature of the Nexo programme or its limited area of operation.

Expert opinion considers programmes like Nexo and the Scottish ChildSmile are effective complements to CWF – not substitutes for, or alternatives to, CWF. I support our health officials considering use of similar programmes in New Zealand but it is misleading for the Democrats for Social Credit to advocate for such programmes simply as a way of preventing or opposing CWF – which is  an effective, beneficial and safe social health measure.

I appreciate you may not accept my arguments or the facts I have presented here. If that is the case I urge you to accept my offer of a right of reply and ongoing good-faith discussion and am happy to help this by making space available on this blog.

I look forward to your response.

References

Ekstrand, K. R., & Christiansen, M. E. C. (2005). Outcomes of a non-operative caries treatment programme for children and adolescents. Caries Research, 39(6), 455–467.

Kirkeskov, L., Kristiansen, E., Bøggild, H., Von Platen-Hallermund, F., Sckerl, H., Carlsen, A., … Poulsen, S. (2010). The association between fluoride in drinking water and dental caries in Danish children. Linking data from health registers, environmental registers and administrative registers. Community Dentistry and Oral Epidemiology, 38(3), 206–212.

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Fluoridation: What’s happening with the New Zealand legislation?

The second reading of the fluoridation bill is now on the order paper for the current parliament. Public submissions have been heard, the Health Committee has reported back to the House and the Ministry of Health (MoH) has provided its own responses to submissions.

Of course, we don’t know yet what the final Act will be like exactly. But the submissions, the committee report, and the MoH responses give us some idea of likely changes to the original bill.

Submissions

I have described before how the anti-fluoride activist groups organise to deluge consultation processes with their submissions. This was certainly the case here and their submissions accounted for most of those opposed to the Bill.

However, because the legislation is about the decision-making process and not the scientific or ethical validity of social health policies simple opposition to fluoridation was irrelevant  – outside the scope of the bill. This was true of most submissions (85%) and these should be considered a waste of every bodies time.

I am surprised the anti-fluoride organisations organising this submission campaign chose to take such an irrelevant approach. Surely if they had put a bit of thought into their efforts they could have directed their submission at relevant aspects such as the consultation process, the decision-making body and the question of referenda.

That said, a small number of the anti-fluoride submissions did address aspects of the bill and these were considered by the Health Committee and the MoH.

Putting aside the anti-fluoride submissions which did not address the bill, 20% percent supported the Bill and 80% opposed to the Bill as currently drafted. Most supported extending fluoridation cover, but disagreed with specific parts of the Bill and suggested changes.

The legislation does not mandate fluoridation

This is a common misunderstanding promoted by anti-fluoride campaigners – obviously attempting to use scare-mongering to motivate their supporters. For example, Fluoride Free NZ formally names the legislation the Mandatory Fluoridation Bill which is dishonest – the correct name of the bill is Health (Fluoridation of Drinking Water) Amendment Bill.”

The bill transfers decision-making from local bodies to District Health Boards (DHBs) – but it does not require DHBs to make a decision about fluoridation. That is up to local DHBs and local conditions such as dental health, likely advantages and establishment costs.

Consideration of other health factors

A number of submitters expressed concern that while the bill requires DHBs to consider dental health effects, consideration of other possible health issues is not provided for. However,  the response from the MoH to this is:

“While DHBs are required to consider the evidence in relation to oral health, DHBs are not prevented from considering other factors, including the effect of fluoridation on overall health. However, officials do not consider it necessary for the Bill to require DHBs to consider these other factors.”

So, consideration of other health factors will depend on specific situations, the board members or public interest. Importantly, DHB’s are not prevented from considering wider health aspects.

Considering the science

I was interested to see that:

” The Ministry of Health is currently exploring options for the ongoing monitoring and assessment of research on fluoridation within the Ministry to align with the implementation of the Bill.”

The MoH sees this as carrying on the role formerly played by the now disbanded National Fluoridation Information Service. But this also goes some way to satisfying a suggestion in my own submission that the assessment of research on fluoridation is carried out by some sort of central expert body (see Fluoride, coffee and activist confusion). My concern was that the DHBs are not really suitable bodies for making expert reviews of the literature and evaluating the current state of the science. Handing this over to a central body could also prevent boards being deluged with misinformation and unsupported claims about the science – a feature of local body consultation which caused so much trouble to councils.

It was the pressure of submission campaigns including misrepresentation and false claims about the science which drove local bodies, who do not have the expertise to consider the science, to request a change to the legislation. DHBs will confront the same situation unless they can direct scientific consultation to a central expert body.

Community consultation

Many submitters (12%), both for and against fluoridation, suggested the bill should specifically require DHBs to consult the community about fluoridation decisions. While the bill did not make such specific requirements it also did not prevent such consultation.

In practice, public consultation will depend on the level of demand for it. It is up to DHBs to decide when consultation is appropriate and there is already a regulatory requirement for DHBs “to foster community participation in health improvement” which could cover that.

There is also provision for the Minister to describe a fluoridation decision as a “significant service change” which would require DHBs to undertake community consultation on regional service plans including fluoridation.

So, the anti-fluoride activist claims of denial of community consultation is wrong. While consultation is not specifically required it is not prevented by the bill and will depend on the level of public interest.

Engagement with local authorities

The health committee is recommending the bill be amended to explicitly require DHBs to consider the views of the drinking water supplier. This accommodates suggestions made by some local bodies who feared the imposition of decisions without considering their local situations.

However, the committee also suggested an amendment to make clear that engagement with local authorities does not require them to consult communities. The DHB which makes the ultimate decision would have that responsibility where necessary.

The Committee also suggested “the Government consider whether
it intends to contribute funding towards the costs of establishing fluoridated water supplies” because there is a “moral hazard arising from the DHBs making a decision that will impose costs on local authorities and ratepayers.”  It looks like the Government has accepted this point as they have already made $12 million dollars available to local bodies setting up new fluoridation systems (see Government commits $12m to help councils cover costs of fluoridation in water supplies.).

Provision of non-fluoridated alternatives

Some local bodies have already introduced “fluoride-free” taps at the request of local anti-fluoride campaigners., The MoH is suggesting an amendment to the bill to make clear that “DHBs can direct local government water supplies in their region on a supply by supply basis if they wish.”

This could make it possible for specific local supplies, like Petone in the Hutt region or some supplies in Christchurch to remain unfluoridated if their communities demand it even if a decision is made to fluoridate a region.

The DHB or the director general of health?

Many of the submitters opposed to the bill in its present form suggest that the decision-maker should not be the DHBs but the Director-General of Health or central government. This is because of the likely low expertise of DHB members, low voter turnout for DHB elections and concerns of legal challenges to DHB decisions. There was also the expressed belief that the anarchic and dishonest coordinated submission campaigns previously experienced by local bodies would simply be transferred to the DHBs.

Some submitter proposed that fluoridation be mandatory thereby removing the need for an elected body to be responsible for the decision making.

The committee report and response from the MoH show that parliament will probably stick with the DHBs as the decision maker. There are some advantages in this (the DHB have responsibilities in health areas) and the proof of the pudding will be in the eating. Will the DHB approach to consultations be able to successfully give more credence to credible and peer-reviewed science than the misinformation and distortions of science promoted by anti-fluoride campaigners?

Possibly. I hope so.

Conclusions

Despite the anti-fluoride campaigns and the resulting deluge of misinformed or misleading submissions, the submission process has been successful. Problems in the current wording of the bill were identified and reasonable solutions to these problems have been advanced.

We should now see how MPs react to the bill and the recommended changes in the second reading. Anti-fluoride activists have carried on an intensive campaign of emails, letters and representations aimed at MPs. On the whole, this will have been counterproductive as MP are surely aware this bill is not about the science or ethics of fluoridation but simply the decision-making process.

I am picking that these campaigns have produced more heat than light and will have little influence on the progress of the bill. However, I do expect a lot of teeth-grinding, hairpulling, garment rending, lamentations that democracy doesn’t work or that various MPs should be shot or otherwise disposed of from anti-fluoride campaigners. This is already happening and will no doubt intensify when the final bill is passed into law.

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Anti-fluoridationists commonly misrepresent Ministry of Health data

Anti-fluoride activists tell porkies about the Ministry of Health’s data on child dental health. They cherry-pick the data to make it appear that community water fluoridation is ineffective. And when challenged to discuss the issue they run away.


I am currently dealing with family issues so am reposting this article, “A challenge to anti-fluoridationers to justify their misrepresentation of New Zealand research”  from April 2016.  It shows how local anti-fluoride activists are misrepresenting the Ministry of Health’s data on child oral health


One of the frustrations I have with the fluoridation issue is the refusal of anti-fluoride activists to engage on the science. They will pontificate, but they won’t engage in discussion.

On the surface, one would think there is a difference of opinion or interpretation of scientific issues and that could be resolved by discussion. Yet local anti-fluoride campaigners refuse to enter into discussion. Again and again, I have offered space here to local anti-fluoride campaigners so that they could respond to my articles and they have inevitably rejected the offer. They have also blocked me, and other people discussing the science, from commenting on any of their social media pages or web sites. Even when they, themselves, call for a debate they reject specific responses I have made accepting that call.

So I am left with the only alternative of responding to their claim with an article here – or on a friendly web or blog site. At least that gives me space to present my argument – I just wish I could get some intelligent responses enabling engagement on the issues.

Misrepresentations repeated

The latest misrepresentation of the science is a claim by the Auckland Fluoride Free NZ Coordinator, Kane Titchener, that recent research proves fluoridation [is] not needed.

It repeats the same misrepresentation made by Wellington Anti-fluoride campaigner, Stan Litras, which I discussed in my article Anti-fluoridation cherry-pickers at it again. Kane has either ignored my article, chosen to ignore it or possibly not even understood it.

So here we go again.

Kane claims:

“A New Zealand study published in Bio Medical Central Oral Health last month shows dental health improved the greatest extent for children in non-fluoridated areas. There is now no difference in dental decay rates between non-Maori children who live in fluoridated areas and non-Maori children who live in non-fluoridated areas, proving that fluoridation is not needed for children to obtain good dental health.”

Although he doesn’t cite the study (wonder why), his use of two figures from the study show he is writing about the paper:

Schluter, P. J., & Lee, M. (2016). Water fluoridation and ethnic inequities in dental caries profiles of New Zealand children aged 5 and 12–13 years: analysis of national cross-sectional registry databases for the decade 2004–2013. BMC Oral Health, 16(1), 21.

His claim relies on the comparison of data for “non-Māori” children in fluoridated and fluoridated areas. No – he doesn’t misrepresent the data – he just ignores the discussion by these authors of problems with simple interpretation of the data for non-Māori because of the fact it is not ethnically uniform. In particular, he ignores the qualifications they place on the data because of the inclusion in non-Māori of data for Pacifica who have poorer dental health than the rest of this group and live predominantly in fluoridated areas. This, in effect, distorts the data by overestimating the poor oral health for “non-Māori” in the fluoridated areas.

The apparent convergence

The data used in this study were taken from the Ministry of Health’s website. This divides the total population of children surveyed into the ethnic groups Māori, Pacific and “Other.” While the “other’ group will not be completely uniform (for example including Pakeha, Asian, other groups) it becomes far less uniform when combined with the Pacific group to form the non-Māori group.

So, Kane salivates over this figure from the paper especially the plots for  non-Māori ethnicities in fluoridated (F) and non-fluoridated (NF) areas.

12903_2016_180_Fig1_HTML

Fig. 1 No obvious decay experience (caries-free) percentages and mean dmft for 5-year old children over years 2004 to 2013, partitioned by Māori and non-Māori ethnicities and fluoridated (F) and non-fluoridated (NF) areas

Yes, that convergence is clear and I can see why Kane is clinging to it – who can blame him. But he completely ignores the warning from the paper:

“It is likely that a substantial driver of this convergence was due to significant changes within the dynamic and heterogeneous non-Māori groups both within and between DHB regions. In effect, the ecological fallacy – a logical flaw whereby analyses of group data are used to draw conclusions about an individual – may be operating within the non-Māori group.”

When the Pacific data is removed (as is the case for the “other” group effectively made up from non-Māori and non-Pacifica) we get the plots below.

Other

Comparison of data for “other” (non-Māori/non-Pacifica) children in fluoridated (F) and unfluoridated (UF) areas.

Nowhere near as useful for Kane’s confirmation bias and the message he wants to promote. OK – there is still some evidence of convergence from about 2007 on between fluoridated and unfluoridated children. But the graphs do show that community water fluoridation is still having  a beneficial effect. And this apparent convergence could be explained by things like the introduction of “hub and spoke” dental clinics after 2004. One problem with this raw data is that children are allocated according to the fluoridation status of the school – rather than their residence. This will lead to incorrect allocation in some cases.

Some data for Pacifica

Just to underline the problems introduced by inclusion of Pacific in the non-Māori group of the study consider the data for Pacifica shown below.

other-pacifica

Data for 5-year-old children. dmft = decayed, missing and filled teeth. The “other” group is non-Māori and non-Pacifica

The oral health of Pacifica is clearly poorer than that of the “other” group.

Also, Pacifica make up about 20% of the non-Māori fluoridated group. So they will influence the data for the non-Māori fluoridated group by reducing the % caries free and increasing the mean dmft.

So Kane, like Stan, is blatantly cherry-picking. He is misrepresenting the study – and its author – by ignoring (or covering up) the qualifications regarding the influence of inclusion of pacific in the non-Māori fluoridated group.

The challenge

Now, I repeat the offer I have made in the past to give a right of reply to both Kane Titchener and Stan Litras. They are welcome to comment here and if they want more space I am happy to give space for separate articles for them in the way I did for the debate with Paul Connett. Now I can’t be fairer than that, can I?

So what about it Stan and Kane? What are your responses to my criticisms of the way you have cherry-picked and misrepresented this New Zealand paper?


NOTE: I have sent emails to both Kane and Stan asking them to respond and offering them right of reply.

UPDATE 1: Great minds and all that – Stan Litras sent out a press release today calling for a nation-wide debate on this issue (see FIND calls for a national debate on fluoridation). However, the seriousness of his request is rather compromised by his reply to my offer of a right of reply to the above article. He did respond to my email very quickly. This is what he wrote:

“Thanks for the offer, Ken, but I have not visited your blog site for a long time, as I object to the way you attempt to defame and discredit me.

You play the man and not the ball, which is not the mark of a reasonable person.

I hope to address that in due course as time permits, but for now I must leave you to indulge yourself without my company.”

So much for his wish for a “national debate” when he will not front up to a critique of his claims about the science.

UPDATE 2: Kane Titchener today also posted a press release today which was the text of the article I discuss in this post (see NZ research proves fluoridation not needed). He also responded quickly to my e-mail. The full text of his response was:

Who is this?”

Rather strange – considering he often pesters me with emails.

So I guess both of them have turned down my offer.

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Fluoridation helps protect adult teeth as well as children’s

Photo credit: Seniors Benefit From Drinking Water Together

Recent research reveals that community water fluoridation benefits adults as well as children.

While research into the effects of fluoridation in adults started earlier than for children, early studies suffered from a lack of information on effects of socioeconomic status and other confounding factors.  Recent studies with adults have been more robust but there is still some confusion – especially since the often cited recent Cochrane systematic survey of the scientific literature on fluoridation was unable to draw conclusions on this because of the strict inclusion criteria used was not suitable.

This new study checked the effects of lifetime access to fluoridation on the dental health of adults from a city in southern Brazil.  It concluded that lifetime access to community water fluoridation is associated with lower tooth decay in adults.

The study is:

Peres, M. A., Peres, K. G., Barbato, P. R., & Hofelmann, D. A. (2016). Access to Fluoridated Water and Adult Dental Caries: A Natural Experiment. Journal of Dental Research, 95(8): 1-7.

The full text of the paper is available here.

The researchers adjusted their data for well-known confounders such as socioeconomic status, the pattern of dental visiting, smoking, educational attainment, income, and age. Use of fluoridated toothpaste was common for all subjects so could not explain the results.

The final data, adjusted fo confounders, showed a greater protection with a longer exposure to fluoridated water. The figure below shows this data for  DMFT (decayed, missing and filled teeth) and DFT (decayed and filled teeth). The use of both measures helps to accommodate the fact that some teeth are missing for reasons other than decay.

The data is present as ratios of DMFT and DFT for the shorter exposure periods ( <50% and 50%-75%) to the values of DMFT and DFT for exposures of >75%.

So, once again a study showing the benefits of community water fluoridation. this time for adults with long time exposure to fluoridation.

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Fluoridation: the truth about heavy metal contamination

Anti-fluoride activists going on about contaminants in drinking water due to fluoridation have it all wrong. If they avoided their knee jerk, chemophobic reactions to certificates of analysis and did some calculations they would realised they are making a fuss about absolutely nothing.


I am currently absorbed in dealing with family issues at the moment so am reposting this article, .” Unfortunately is is still very much relevant.


Sometimes anti-fluoride propagandists end up shooting themselves in the foot. This always seems to happen when they produce “evidence’ that fluoridating chemicals are loaded with toxic heavy metals.

It feels like shooting fish in a barrel to debunk their use of analytical figures because the data they produce always shows them to be completely wrong. I wrote about this before in Fluoridation: emotionally misrepresenting contamination. So, I am effectively repeating myself by discussing the meme image below that Fluoride Free NZ is currently circulating in social media.

Hill lab

Still, this time, I will show how insignificant these analytical figures by comparing the calculated final concentrations in tap water – due to addition of the chemical – with measured concentrations for these contaminants in Hamilton tap water.

Added contaminants as percentage of MAVs

But first – what contribution would this sample of fluorosilicic acid make to the contaminant levels in Hamilton’s tap water – and how do these levels compare with the maximum acceptable values (MAVs) defined in New Zealand’s Drinking Water Standards? The values for the MAVs are published in:

Ministry of Health. (2008). Drinking-water Standards for New Zealand 2005 ( Revised 2008 ) (Vol. 2005). Wellington.

In this table, the “Tap water (mg/L)” data are the calculated final concentrations after addition of the fluoridating agent in the meme. The “%age of MAV” data are these values expressed as a percentage of the maximum acceptable values (MAVs) for the contaminants.

Impurity MAV (mg/L) Tap water calculated (mg/L) %age of MAV
Aluminium 0.1 8.69E-05 0.0869
Antimony 0.02 < 3.56E-07 <0.0018
Arsenic 0.01 1.26E-05 0.1264
Barium 0.7 4.27E-06 0.0006
Cadmium 0.004 2.37E-07 0.0059
Chromium 0.05 4.74E-06 0.0095
Copper 1 1.19E-06 0.0001
Iron 0.2 1.62E-04 0.0810
Lead 0.01 2.37E-07 0.0024
Manganese 0.04 3.56E-06 0.0089
Mercury 0.007 < 1.98E-07 <0.0028
Molybdenum 0.07 < 3.56E-07 <0.0005
Nickel 0.08 3.95E-06 0.0049
Selenium 0.01 < 1.98E-07 <0.0020
Uranium 0.02 2.05E-06 0.0103

Sorry, I have had to use scientific formating for some numbers because the final calculated concentrations in tap water are so low. On average, the calculated concentration  of these contaminants due to the fluoridating agent is about 0.02% of the MAV.  The largest relative contribution is for arsenic – just over 0.1%.

Regulations require that the contribution of contaminants from fluoridating agents should always be less than 10% of the MAV . The actual level of contaminants in this particular sample is well below those regulated maxima.

The Fluoride Free NZ meme is just promoting naive chemophobic scaremongering about absolutely nothing. These activists just haven’t bothered calculating what the analytical data means for the final concentrations in tap water. Or even bothered comparing the data with the regulated maximum amounts allowed for fluoridating chemicals. These values are available in Standard for the Supply of Fluoride for Use in Water Treatment.

Added contaminants as a percentage of concentrations in inlet water and treated water.

Let’s now compare the estimated contribution from contaminants in this sample of fluorosilicic acid to the levels of the very same contaminants in the Hamilton water. I have taken data from this document issued by the Hamilton City Council:

Waikato River and Treated Drinking Water Comprehensive Analysis Report 2013/14

The next table is for samples taken on 18th July 2013 at the intake to the treatment plant (that is the source water before treatment). The “Added FSA%” is the calculated level of impurity resulting from fluoridation expressed as a percentage of the impurity naturally present in the source water.

Impurity Intake (mg/L) Added FSA%
Aluminium 1.68E-01 0.05
Antimony 8.50E-04 <0.04
Arsenic 1.96E-02 0.06
Barium 1.88E-02 0.02
Berylium <1.10E-04 0.18
Cadmium <5.30E-05 0.45
Chromium <5.30E-04 0.89
Copper <5.30E-04 0.22
Iron 2.94E-01 0.06
Lead 1.18E-04 0.20
Manganese 2.15E-02 0.02
Mercury <8.00E-05 <0.25
Molybdenum 3.80E-04 <0.09
Nickel <5.30E-04 0.75
Selenium <1.10E-03 <0.02
Tin <5.30E-04 0.22
Uranium <2.10E-05 9.78
Zinc 8.13E-01 0.00

Now, a similar calculation and comparison – this time “Added FSA%” is the calculated level of impurity resulting from fluoridation expressed as a percentage of the impurity already present in the “treated water” – which is the final tap water. (At this time the Hamilton water supply was not fluoridated).

Impurity Treated (mg/L) Added FSA%
Aluminium 2.04E-02 0.43
Antimony 8.00E-04 <0.04
Arsenic <1.10E-03 1.15
Barium 1.26E-02 0.03
Berylium <1.10E-04 <0.18
Cadmium <5.30E-05 0.45
Chromium <5.30E-04 0.89
Copper 8.00E-04 0.15
Iron <2.10E-02 0.77
Lead 4.82E-04 0.05
Manganese 1.75E-03 0.20
Mercury <8.00E-05 <0.25
Molybdenum 3.70E-04 <0.10
Nickel 3.52E-03 0.11
Selenium <1.10E-03 <0.02
Tin <5.30E-04 0.22
Uranium <2.10E-05 9.78
Zinc 4.82E-03 0.14

The extremely low levels of contaminants – both calculated and already in the intake water and final treated water – mean some of the calculations are rather meaningless. Especially as some of the analysed values are given as less than the detection limit.

However, the very low calculated contribution of contaminants from this fluorosilicic acid sample – usually < 1% of that naturally present – shows how ridiculous the Fluoride Free NZ claims about contamination introduced by fluoridating agents is.

Never trust anti-fluoride campaigners

Fluoride Free NZ is simply scaremongering – relying on naive chemophobia where just the chemical name and analytical data (even where the “<” symbol indicates below the level of detection) seem to scare people.

This example illustrates, once again, that the claims made by anti-fluoride and similar activists should never be accepted at face value. They should always be checked against reliable sources.

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Bottle fed infants: fluoridated water not a problem

Parents need no longer be concerned about using fluoridated water for baby formula. Photo credit: Life insurance for your heirs

New recommended fluoride dietary intakes by infants and young children in Australia and New Zealand were recently published. The updated values are available online at Nutrient Reference Values for Australia and New Zealand.

This is a regular update – the Australian National Health and Medical research council advises these recommendations be reviewed every 5 years. But the new recommendations are interesting because the upper limit for fluoride intake for infants and young children is substantially higher than the previously recommended upper limit.

Public health policy in Australia and New Zealand aims to adjust fluoride intake at the population level to be high enough to prevent dental caries but low enough not to cause moderate or severe dental fluorosis or other adverse effects. But health professionals have noted an anomaly in recent years.  Dietary intake of fluoride by children may exceed the previously recommended upper levels – even when community water fluoridation levels are within the recommended targets. Despite this the occurrence of moderate or severe dental fluorosis in Australia and New Zealand was rare.

This led to health authorities acknowledging that, for example, bottle-fed infants may sometimes exceed the upper limits for dietary fluoride intake – but still recommending this was harmless. Anti-fluoride activists misrepresented this advice by claiming health authorities were recommending that fluoridated water not be used for preparing formula for bottle feeding. Their claims are incorrect and alarmist. The “warning” simply provided advice that there was no risk of harm but the if parents were concerned they should occasionally use non-fluoridated water to make up baby formula.

In part, this current report is a response to that conundrum.

Why the change?

Anti-fluoride propagandists will no doubt attack this change. They have made capital out of the situation in the past by claiming that infants and young children are getting dangerous levels of fluoride in their diet. They, of course, ignore or hide the fact that despite this, levels of moderate and severe dental fluorosis have not been a problem. They, also misrepresent the situation regarding dental fluorosis and its causes – see Dental fluorosis: badly misrepresented by FANNZ and Water fluoridation and dental fluorosis – debunking some myths.

However, the expert working group who reviewed the literature and came up with the new recommendations did have their reasons. And these were more than just the absence of moderate and severe dental fluorosis.

They also concluded the previous recommendation was not consistent. This is because it was based on the US Environmental Protection Agency’s use of mean dietary intake and not the higher percentile fluoride intake which should have been used for the upper limit.

Consequently, their recommendation for the upper limit of fluoride intake for children up to 8 years of age is 0.20 mg F/kg bw/day (kg bw = kg body weight). The previous limit was 0.1 F/kg/ bw/day. This produces the following upper limits for children of different ages.

In Australia and New Zealand, the estimated upper range of total daily fluoride intake for different age groups ranges from 0.09to 0.16 mg F/kg bw/day – considerably lower than the new recommended upper limit of 0.2 mg F/kg bw/day.

Conclusion

Will anti-fluoride campaigners top claiming that bottle-fed infants consume dangerous levels of fluoride if their formula is made with fluoridated water?

And the rest of us should not longer make the concession that intake levels are above the recommended upper limits – because they aren’t.

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No, fluoridation is not associated with leading causes of death

We are all going to die but fluoridation isn’t killing us.

Oh, dear – the local anti-fluoridation people are at it again. More cases of fiddling statistics  – and yet again the guilty party is the US anti-fluoridation activist Karen Favazza Spencer. She should really take some advice about statistics.

Although I suspect she doesn’t care – she is just once again cherry picking in an attempt to paint a bad picture of community water fluoridation.

In this case, she claims the death rates for the leading causes of death in the USA are up to 30% higher in the more fluoridated states than in the less fluoridated ones. And here is her cherry-picked table to “prove it.

Her conclusions are wrong, of course. Look at what we find if we use the data for all the states instead of a few selected ones,  and look at it for signs of any correlation between fluoridation extent and death rates? The data is readily available.

I have done this and found a statistically significant correlation in only one case – cancer. Here is that data and the regression line accounts for about 10% of the variance in cancer rate. Obviously, other factors are involved.

But, wait – there is more. As I explained in my last post Anti-fluoridationists exploit infant deaths by fiddling statistics such statistically significant associations often disappear when other important factors are included in the regression analysis.

So let’s look at what happens when we include mean state elevation in the statistical analysis. As I explained last time there is an association between fluoridation extent and mean state elevation which means that fluoridation is often acting as a proxy for elevation in statistical analyses. Multiple regressions including both fluoridation extent and mean state elevation picks this up.

This table shows the results of such multiple regressions.

Table: Association of death cause with fluoridation extent and mean state elevation. Results from a multiple regression

Fluoridation 2014

p value

Mean altitude

p value

Amount of variance accounted for (%)
Heart disease 0.542 NS 0.007 ** 19.7
Cancer 0.363 NS <0.001*** 38.6
Stroke 0.955 NS 0.180 NS 4.4
Alzheimer’s 0.274 NS 0.834 NS 3.3
Diabetes 0.955 NS 0.445 NS 1.4
Kidney disease 0.441 NS 0.017* 16.3

What does that tell us? Well, the apparent association of cancer death rates with fluoridation is false – it disappears when altitude is included.

None of the death rates for any of the causes of death had a statistically significant association with fluoridation. But heart disease, cancer, and kidney disease were significantly associated with altitude. These associations accounted for from 16% to 39% of the variances in the death rates. The role of mean state altitude may have something to do with the size of cities or possibly improved health at higher elevations (the death rates declined with elevation for all causes considered).

I can only finish with the same words of warning I used last time:

“So, once again the lesson is – never take at face value the claims made by anti-fluoridation activists – no matter how “sciency” their information looks or what data they invoke to “prove” them.

Always check such claims for yourself.”

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Anti-fluoridationists exploit infant deaths by fiddling statistics

A useful reminder of how activists lie with statistics

The local anti-fluoride people have not stopped rabbiting away with their “science” – searching for anything bad they can argue is caused by community water fluoridation. The latest claim they make – fluoridation is responsible for infant deaths!

And they have some statistics to “prove” this. The table below presented by well-known US anti-fluoride activist, Karen Favazza Spencer, in her article America First – Chemical Warfare on Infants:

That table is simply lifted from a conspiracy style web page Why Pregnant Women Should Not Drink Fluoridated Water.

OK – these statistics might fool some people – especially if you have a bias to confirm. But the more critical person might pick up that these figures are most likely cherry-picked and want to see the full data set or some analysis of the data.

It’s not hard to find this data as there are tables of all sorts of things for US people organised by state. So, is there a relationship between infant deaths in each state and the extent of fluoridation in each state?

There actually does appears to be one at first sight – here is the graph of the data for infant deaths in 213 plotted against the extent of fluoridation in 2012.

ID-fl

But, just a minute – it is not actually statistically significant (p=0.106) and would account for only about 5% of the variance in infant deaths. Fluoridation is certainly not the main factor – and probably involved at all if other factors are considered.

Here I will just take into account the influence of state elevation – because I know from previous work that fluoridation extent is related to mean state elevation (see ADHD linked to elevation, not fluoridation).

Here is that relationship for the extent of fluoridation in 2012:

Fl-elev-2012

So, the extent of fluoridation in each state is related to mean state elevation and this relationship is statistically significant (p=0.005). Actually not surprising as the larger and older cities where fluoridation might be expected are generally situated at lower elevations for a number of reasons.

But what is the relationship between infant death and mean state elevation? Well, it is stronger than for the extent of fluoridation (p=0.002). Elevation accounts for about 18% of the variance in infant deaths in 2013.

ID-ele

Finally, let’s combine both elevation and extent of fluoridation into a multiple regression and see what the relationship when both factors are combined.

This multiple regression shows a statistically significant association (p=0.007) of the extent of infant deaths in each state in 2013 with the mean state elevation. However, there is no statistically significant association (p=0.592) with the extent of state fluoridation.

So while infant deaths could be explained by mean state elevation and most probably one or more other factors, they certainly are not explained by the extent of fluoridation. Not at all!

Preterm birth and conspiracy theory

In her article, Karen Favazza Spencer makes the bald claim “Fluoridation is positively correlated with preterm birth and increased death rates by state “ – again citing from the conspiracy style web page mentioned above.

Sure, that page makes that claim – “Domestic water fluoridation was independently associated with an increased risk of PTB [preterm birth].”  But that is hardly credible evidence because that page goes on the say:

“This study was never published nor was any follow-up research done, despite the fact that 2 years earlier, the US Institute of Medicine reported: ‘Those born preterm have an appreciable risk of long-term neurological impairment and developmental delay.'”

Strange! It is not hard to find data for preterm birth. In fact, here it is for 2014 compared with the extent of state fluoridated in 2012:

Clearly, there is no association between preterm births and extent of fluoridation. Yet that web page claimed there was and that the information had been suppressed!

I guess that is another way ideologically motivated activists “prove” these sort of things – invoke a conspiracy theory to claim a relationship exists but the data is suppressed.

So, once again the lesson is – never take at face value the claims made by anti-fluoridation activists – no matter how “sciency” their information looks or what data they invoke to “prove” them.

Always check such claims for yourself.

Similar articles

Bottle fed infants: fluoridated water not a problem.

Parents need no longer be concerned about using fluoridated water for baby formula. Photo credit: Life insurance for your heirs

New recommended fluoride dietary intakes by infants and young children in Australia and New Zealand were recently published. The updated values are available online at Nutrient Reference Values for Australia and New Zealand.

This is a regular update – the Australian National Health and Medical research council advises these recommendations be reviewed every 5 years. But the new recommendations are interesting because the upper limit for fluoride intake for infants and young children is substantially higher than the previously recommended upper limit.

Public health policy in Australia and New Zealand aims to adjust fluoride intake at the population level to be high enough to prevent dental caries but low enough not to cause moderate or severe dental fluorosis or other adverse effects. But health professionals have noted an anomaly in recent years.  Dietary intake of fluoride by children may exceed the previously recommended upper levels – even when community water fluoridation levels are within the recommended targets. Despite this the occurrence of moderate or severe dental fluorosis in Australia and New Zealand was rare.

This led to health authorities acknowledging that, for example, bottle-fed infants may sometimes exceed the upper limits for dietary fluoride intake – but still recommending this was harmless. Anti-fluoride activists misrepresented this advice by claiming health authorities were recommending that fluoridated water not be used for preparing formula for bottle feeding. Their claims are incorrect and alarmist. The “warning” simply provided advice that there was no risk of harm but the if parents were concerned they should occasionally use non-fluoridated water to make up baby formula.

In part, this current report is a response to that conundrum.

Why the change?

Anti-fluoride propagandists will no doubt attack this change. They have made capital out of the situation in the past by claiming that infants and young children are getting dangerous levels of fluoride in their diet. They, of course, ignore or hide the fact that despite this, levels of moderate and severe dental fluorosis have not been a problem. They, also misrepresent the situation regarding dental fluorosis and its causes – see Dental fluorosis: badly misrepresented by FANNZ and Water fluoridation and dental fluorosis – debunking some myths.

However, the expert working group who reviewed the literature and came up with the new recommendations did have their reasons. And these were more than just the absence of moderate and severe dental fluorosis.

They also concluded the previous recommendation was not consistent. This is because it was based on the US Environmental Protection Agency’s use of mean dietary intake and not the higher percentile fluoride intake which should have been used for the upper limit.

Consequently, their recommendation for the upper limit of fluoride intake for children up to 8 years of age is 0.20 mg F/kg bw/day (kg bw = kg body weight). The previous limit was 0.1 F/kg/ bw/day. This produces the following upper limits for children of different ages.

In Australia and New Zealand, the estimated upper range of total daily fluoride intake for different age groups ranges from 0.09to 0.16 mg F/kg bw/day – considerably lower than the new recommended upper limit of 0.2 mg F/kg bw/day.

Conclusion

Will anti-fluoride campaigners top claiming that bottle-fed infants consume dangerous levels of fluoride if their formula is made with fluoridated water?

And the rest of us should not longer make the concession that intake levels are above the recommended upper limits – because they aren’t.

Similar articles

Fluoride, coffee and activist confusion

Havana Coffee Works in Tory Street, Wellington. Great coffee and chance to see roasting in action. On the site of what was the old Wellington Milk Department in the 1950s.

I have been in Wellington for the Parliamentary select committee hearings on fluoridation. Well, that was the excuse – I was really there to catch up with my family (always a joy and am amazed at how tall my grandson has become) and to enjoy the great food in Wellington cafes.This time I

This time I also set out to acquire some freshly-roasted coffee beans from one if the many roasters in Wellington.

The Havana roaster turned out to be a surprise. Not only are their coffee beans excellent ( I am looking forward to getting home and drinking coffee made with them) – they are based in Tory Street as the site of what used to be the old Milk Department. Some of you may still remember the days when milk was delivered to your house in the middle of the night by a milkman. My Dad was one of those milkmen, and my siblings and I all spent time helping him deliver milk in the dead of night. So that building brought back memories. Even got to walk along Channing street on the way back to my hotel. You wouldn’t know it now but that street was very disreputable in the 50s because of the opium dens in the old houses.

Select Committee Hearings

These were interesting. Submissions were called for on  Health (Fluoridation of Drinking Water) Amendment Bill currently before parliament. This legislation is not about fluoridation itself. It is about how decisions should be made – about the process, not the science. In effect, it proposes transferring decisions from local councils to District Health Boards.

Pressure for the law change came from local councils who were sick to death of the hounding from activists and being forced into making decisions – not about whether to fluoridate or not – but about the science. Activist submitters continued to deluge them with passionately-worded submissions full of scientific claims – councillors with no scientific skills were being forced into making decisions about the science – were the activists correct in their claims that fluoridation causes all the ills known to mankind or should they accept the science presented by the experts. After all, activist submissions could look very sciencey – they were often full of citations to the scientific literature!

True to form the anti-fluoride activists deluged the select committee with submissions which were irrelevant to the bill – very few of them actually suggested changes or showed any evidence they had read the bill. No, they did their usual trick of preaching about the “science” – their claims of harmful effects from fluoridation and that it does nothing for oral health anyway.

It is amazing to hear people make outrageous claims about the scientific literature – claims which make clear they have never bothered to read the source they are citing. I guess they think they can get away with such porkies and misrepresentations because they are talking to politicians. However, my impression was this failed at these hearings – unless submitters raised suggestions about the process they were simply politely thanked and sent away.

So I found it frustrating to hear such lies being peddled about the science (and discussion by the public was not allowed) but confident in the fact the select committee was just humouring these people. Responses from committee members were always about process – not the scientific claims.

My submission

There were only a few submissions which dealt properly with the wording of the bill – the vast majority were just empty anti-fluoride rhetoric. I made a submission as an individual scientist but also as part of the Making Sense of Fluoride (MSoF) team. It was great to catch up with MSoF people who I tend to talk with on-line every day but have not till now met in person.

This was my oral submission:


As Monty Python used to say: “And now for something completely different.”

I support this bill as far as it goes but don’t think it will solve the basic problems without changing the way the science is considered. I want to suggest a change.

The current submissions show the problem. This committee has been inundated with large numbers of written and oral submissions. Many of these are duplicates or form letters. Most are opposed to community water fluoridation and usually make scientific claims – such as fluoride is a neurotoxin, that it causes a high prevalence of dental fluorosis or uses contaminated chemicals.

Submissions often cite scientific articles – some have even attached copies of these articles. This sort of thing can impress the layperson – perhaps some of the members of this committee are impressed? After all, it is easy to fool the ordinary person with scientific claims, citations, documents and publications. Advertisers do it all the time.

But this committee is simply not considering the science. Political committees – parliamentary, local body or District Health Board should not make scientific decisions. They do not have the skills for this. Yet that is what most of these submissions are asking of this committee. It’s what was being asked of local councils and it will be what is asked of DHBs.

Consideration of the science behind community water fluoridation requires people with scientific and health skills. Such people need to check evidence provided, check citations when they are presented, check what the scientific literature actually says (which could be very different to what submitters claim). Proper scientific consideration requires that the claims and cited scientific literature need to be considered intelligently and critically. The wider literature needs to be consulted. Cited claims need following up.

I have attached a couple of documents that do this – these are responses to documents used by several submitter arguing against community water fluoridation.

The current wording this bill requires DHBs to consider the scientific evidence. That just invites opponents of community water fluoridation to inundate DHBs with the sort of submission this committee has received – and local councils have been inundated with. DHBs are no better equipped to deal with this than this committee or local councils.

I suggest a change requiring DHBs to take advice on the scientific evidence from central bodies – the Ministry of Health and the Public Health Advisory Committee. This would transfer responsibility for scientific considerations to central bodies better equipped to do that evaluation.

The Public Health Advisory Committee has a legislated role to consider questions like this and advise the Minister. It is also able to consult interested organisations, experts like the Royal Society and the Prime Minister’s Chief Scientific Advisor who performed the most recent fluoridation review. It can also consult appropriate individuals.

This would not remove the right of lay persons to make submissions about the science – it simply redirects those submissions to a more appropriate body.

I think a change like this should be welcomed by everybody. It removes from DHBs the impossible job of making decisions about the science they are not equipped to make. It provides a proper venue for the science to be considered intelligently and critically. It is a credible and authoritative body for scientific organisations, health organisations, activist groups and the ordinary person who has concerns on this issue – whether for or against community water fluoridation.

After all – if someone has a genuine concern or has evidence they think will stand up to scientific scrutiny why should they want to waste time submitting it to a committee of politicians? Wouldn’t they be far happier knowing they are appealing to people who have the skills to evaluate their concerns properly?

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