Category Archives: SciBlogs

Misrepresenting fluoride science – an open letter to Paul Connett

Connett Blenheim

A poster for Connett’s Blenheim meeting – scaremongering because there is no proposal for mandatory fluoridation in New Zealand.

A new year and a new speaking tour of New Zealand by US anti-fluoride campaigner Paul Connett. Looking over the presentation he is giving at his New Zealand meetings I find he has absolutely nothing new to say. It’s all been said before – and all his claims have been debunked before.

His visit this year is slightly unusual – the first time I am aware he has visited in winter. Perhaps the local anti-fluoride movement has decided they need to get him early because of the impending introduction of new legislation on community water fluoridation (CWF).

In this open letter to Paul, I respond briefly to the points he makes in his current presentation and will link to a fuller discussion of each point in earlier posts. Many of these links will be to my debate with Paul Connett 3 years ago. You can download the full debate (Connett & Perrott, The Fluoride debate – 2014) or find the individual posts at Fluoride Debate.

Finally, I have offered Paul the right of reply here. I believe that participation in a good-faith discussion is the most scientifically ethical response to my open letter.


Dear Paul,

I wish to challenge claims you made in your 2016 New Zealand speaking tour. Most of these claims were refuted in our 2013/2014 debate but it is worth itemising some of them here because you are continuing to rely on them.

I, of course, offer you the right of reply and access to an open good faith discussion here if you feel I have misrepresented you in any way.

Fraudulent charges of scientific fraud

Fraud claim

From Connett’s 2016 New Zealand presentation

Scientific fraud is an extremely serious offence and accusations should not be made lightly. Yet you have accused New Zealand scientists involved in the Hastings trial of scientific fraud without even citing the study’s reports or publications. You have relied simply on an out-of-context sentence in a letter from a departmental official and unsubstantiated claims about changes in methodology. I pointed this out to you in our 2013/2014 debate  yet you are persisting in this defamation of researchers who are no longer here to defend themselves. You have even gone as far as producing an internationally distributed newsletter entitled “New Zealand Fluoridation Fraud” which was promoted by Fluoride Free NZ activists in this country.

You base your charge of “fraud'” on:

  1. An out of context quote from an internal letter by a director,
  2. Abandonment of Napier as the planned control city at the beginning of the study, and
  3. Alleged changes in the diagnostic procedures used during the course of the trial.

1: A letter from a divisional director expressing his frustration at developing a description “with meaning to a layman” is not evidence of “fraud,” or an attempt to distort the evidence. Scientists are always being urged by officials to make their findings more accessible and understandable to the public.   Your presentation of it as such is equivalent to the 2009/2010 “climategate” misinformation campaign launched by climate change deniers using out-of-context quotes from scientists emails. In that case, we know the real fraud was carried out by those attempting to deny the science and discredit the scientists.

2: Yes, the original plan was to use Napier as a control non-fluoridated city alongside the fluoridated city of Hastings. This was abandoned when data showed a lower incidence of tooth decay in Napier and it was judged unsuitable as a control because of differing soil chemistry which would have introduced an extra confounding factor. While this reduced the Hastings experiment to a longitudinal study, comparisons were made with other non-fluoridated New Zealand cities.

Surely this was a sensible solution to a problem? – and these are always occurring in long-term studies as any researcher familiar with such studies will confirm. Yet, in our debate, you irresponsibly described these reasons as “bogus.” As I said in our debate:

“That is the problem with conspiracy theories – they paint the world black and white which is very unrealistic. I expected far more professionalism from Paul than this.”

This is not the sort of rational assessment expected from a scientific review but sounds more like the declaration of a biased political campaigner.

3:  The diagnostic procedure used in the Hastings experiment were described in the first paper of the series reporting results (Ludwig 1958). Subsequent papers (Ludwig and Ludwig, et al., 1959, 1962, 1963, 1965, 1971) refer to this description and confirm it continued to be used. So where is the evidence for a change in diagnostic procedure?

Yes, there were changes in tooth filling procedures used by New Zealand dental nurses around the time this trial started. But even the anti-fluoride  Colquhoun & Wilson (1999) confirm attempts were made to use a consistent filling procedure in the trial – quoting from a file they received from their Official Information Act request:

“At the commencement of the Hastings fluoridation project steps were taken to ensure that the practice of preparing prophylactic type fillings by dental nurses was discontinued.

Of course, longer term trial like this always have a possibility of technician (or dental nurse) differences and good trial managers attempt to reduced such differences.

Perhaps one way to confirm that such “teething problems” (pardon the pun) did not have an overriding effect is to see that the improvements in oral health measured as differences from the 1954 start were also observed if 1957 was taken as the start (and also for later dates). In our debate I showed this to be a fact using the graphs below.

Hastings data shows similar improvement in oral health even if the project had started in 1957. Plots are for different ages.

Paul, you description of honest research, no matter what its limitations, as fraudulent is irresponsible. Considering your motives for this description and the way you have distorted the situation I would even describe your behavior itself as fraudulent.

Misrepresenting WHO data.

You repeat the same misleading interpretation of the World Health Organisation (WHO) data that we discussed in our debate where you attempted to avoid my criticisms and in the end did not have a sensible response. Despite the refutation, you continue to promote the following misleading graph every chance you get (see also Fluoridation: Connett’s naive use of WHO data debunked):

WHO data

Slide from Connett’s 2016 New Zealand presentation

These data do not support your claim of no difference between the rates of improvement of oral health in fluoridated and unfluoridated countries because there is no attempt to account for all the different factors influencing dental health. Robyn Whyman pointed this out in his report for the National Fluoridation Information Service – Does delayed tooth eruption negate the effect of water fluoridation?:

“Inter-country comparisons of health status, including oral health status, are notoriously difficult to interpret for cause and effect, because there are so many environmental, social and contextual differences that need to be considered.”

It is far more rational to compare regions within countries and you have purposely omitted the WHO data where fluoridated and unfluoridated areas within individual countries were compared.

Here is that WHO data for Ireland which shows a clear benefit in fluoridated areas.

As I said in my post Fluoridation: Connett’s naive use of WHO data debunked:

“I showed this graph to Connett at the beginning of our debate on fluoridation. throughout the next few months he continued to confuse the issue and I kept coming back to it. Finally, he said in his closing statement, “My apologies. I should have checked back.”

An acknowledgment, of sorts, that his use of the WHO data is wrong in his graphs – but he continues to misrepresent it in this way!”

Isn’t it about time you stopped promoting this invalid and misleading use of the WHO data?

Nexo and ChildSmile are complimentary to CWF – not alternatives

Nex and CS

From Paul Connett’s 2016 New Zealand presentation.

You are being disingenuous in promoting oral health programmes like the Danish Nexo and Scottish ChildSmile programmes, as “alternatives” to community water fluoridation (CWF). Health authorities do not see them as alternatives – more as possible complimentary social programmes. The British Dental Association supports both the Scottish ChildSmile programme and CWF. In Scotland it has come out publicly called for communities to move towards introducing water fluoridation. In the absence of CWF, UK health professionals see ChildSmile as “the next best thing – a rather expensive substitute for the fluoridation schemes that have never been introduced.”

I discussed the ChildSmile programme in my article ChildSmile dental health – its pros and cons and in our debate (see Fluoride debate: Ken Perrott’s closing response to Paul Connett?). It, and the Nexo programme, use approaches of child and parent education, toothbrushing supervision and programmes, and  health education initiatives based principally on public health nurses and health visitors attaching themselves to particular schools in order to give oral health advice to children and parents. Subject to parental consent, they also arrange for children who are not registered with a dentist to undergo check-ups and, if necessary, treatment.

Both programmes also provide regular fluoride varnishes for children’s teeth (so much for being an alternative to fluoride).

The point is that elements of these programmes are probably already incorporated into the social health policies of many countries. They certainly are in New Zealand. The introduction of a social health policy like CWF does not mean that programmes like the Nexo and Childsmile, or elements of them, are abandoned by health authorities. The research still shows that CWF reduces tooth decay even when other programmes like this, the use of fluoridated toothpaste and restriction of sugar consumption are practiced (see for example Blinkhiorn et al., 2015).

Interestingly, though, because sometimes programmes like tooth varnishes are targeted at the more vulnerable children in non-fluoridated areas these may lead to difficulties in drawing conclusions from simple comparison of fluoridated and unfluoridated areas. I discussed this in my article on mistakes in one of John Colquhoun’s  papers – Fluoridation: what about reports it is ineffective? – where children from non-fluoridated areas received preferential fluoride varnishing.

There is no single “silver bullet,” for solving the problem of tooth decay so why not use programmes like CWF and Childsmile/Nexo, or elements of the these, together?

In fact, that is exactly what is happening in New Zealand.

Asserting CWF out of step with the science

You claim:

“A better guide as to what nature thinks about the safety of fluoride is the level found in mother’s milk.”

This is simply weird, a naive example of the naturalistic fallacy.

Nature doesn’t think – such an arguments could be used against everything humanity has done to ensure that we have a better quality and length of life than “offered by nature.” As I pointed out in our debate, we are used to other elements being deficient in mothers milk and therefore requiring supplementation (see also Iron and fluoride in human milk for discussion of an evolutionary perspective vs a naive appeal to nature).

Your assertion:

“in mammals not one single biochemical process has been shown to need fluoride to function properly”

is simply deceptive – knowingly so. Fluoride may not play a biochemical role but it does play a chemical one. It is a normal and natural component of bioapatites – bones and teeth. And when present in optimum amounts confers strength and low solubility. Surely as a chemist you are familiar with the fact that minerals like apatite usually do not occur in the ideal form, as end members of a chemical series. In practice, no bioapatites are “fluoride-free.”

I demonstrated the difference between real world apatites and the ideal end members in our 2013/2014 debate using this figure. As a chemist this should be obvious to you.

apatite-2

In the real world bioapatites like bones and teeth always contain fluoride as a normal and natural constituent. The end members hydroxylapatite and fluoroapatite are not real models for natural bioapatites.

You claim that:

“With fluoridation: the chemicals used are not pharmaceutical grade but contaminated waste products from the phosphate fertilizer industry.”

But none of the chemicals used in water treatment, or the water itself, are of  “pharmaceutical grade.” Water plants and water treatment have their own grading system for the chemicals used.

In fact, comparing the certificated concentrations of contaminant elements in fluoridating chemicals used with the same contaminants already in the source water, we find that fluoridating chemicals are not a real source of contamination. We should be more concerned about the source water itself. I presented data to show this in my article Chemophobic scaremongering: Much ado about absolutely nothing. In most cases contamination from the fluoridating chemical is less than 1% of the contaminant concentration already in the source water.

Your reference to “contaminated waste products” is simply naive (or dishonest since you have chemical training) chemophobic scaremongering

Misrepresenting facts on dental fluorosis

dental fluorosis

Paul Connett cites an irrelevant figure in his 2016 New Zealand presentation.

Your claims regarding dental fluorosis are presented as an argument against CWF and in that context are very misleading:

1: The deceit of not identifying contribution from CWF.

Your slide refers to all forms of dental fluorosis and to all areas – fluoridated and fluoridated. It is very misleading to infer that CWF is responsible for a dental fluorosis prevalence of 41%  of dental fluorosis. In fact, CWF makes only a small contribution – often not detectable as was the case with the New Zealand Oral Health survey illustrated below (see Dental fluorosis: badly misrepresented by FANNZ).

Unfortunately, even the recent Cochrane Fluoridation Review (Iheozor-Ejiofor et al., 2015) mistakenly presented the dental fluorosis data without differentiation between fluoridated and non-fluoridated areas. My calculations from their data indicated tyhe prevalence of dental fluorosis due to CWF is more like 7% – much less than your 41% (see  Cochrane fluoridation review. III: Misleading section on dental fluorosis).

2:  Scaremongering by not differentiating between mild and severe forms.

Your 41% sounds scary – especially with the implication it is caused by CWF. But at least your acknowledge that the prevalence of more severe forms is much less. That is obvious from my figure above and from your later slide acknowledging a 3.6% prevalence of moderate and severe dental fluorosis in American teens.

This figure from the National Research Council review shows that CWF (which usually uses a concentration of 0.7 ppm) does not contribute at all to severe dental fluorosis.

Severe-dental-fluorosis

Usually only the moderate and severe forms of dental fluorosis are considered of aesthetic concern – and the milder forms are often judged favourably by parents and teenagers.

What you did not say is that CWF does not contribute at all to moderate and severe forms. These forms are completely irrelevant to the discussion of CWF and it is dishonest to use it as an argument against CWF. Again, my calculation from the Cochrane data indicates the contribution of CWF to dental fluorosis of aesthetic concern was within the measurement error.

If you are really concerned about dental fluorosis, and especially the more severe forms of aesthetic concern, you should be paying attention to high natural sources of fluoride in some regions, industrial pollution and the possibility of obsessive consumption of toothpaste by children.

Brain damage?

Brain

Wild claim by Connett in 2016 New Zealand presentation. There is absolutely no evidence that CWF is harmful to the brain.

Paul, you have been uncritically dredging the scientific literature for articles you can use to imply fluoride is toxic or a neurotoxicant. Of course you will find studies supporting your bias that you can cherry-pick. A similar uncritical dredging will produce far more articles showing water is toxic! Such confirmation bias is scientifically unethical. We should always read the scientific literature intelligently and critically.

Applying a bit of objectivity we see that almost all the studies you rely on use exposure levels far greater than the recommended levels for CWF. Many of the animal studies considered exposure 50 to 100 times those levels or more. The quality of many of the research reports you rely on is not good – a point I think you have acknowledged in the past.  The human studies you rely on have, almost without exception, involved regions of endemic fluorosis quite unrepresentative of regions where CWF is used (I discuss the two exceptions below). None of them properly considered relevant confounding factors.

The exceptions

You promote Malin and Till (2015) as evidence that CWF causes attention deficit hyperactivity disorder (ADHD). You have made no critical assessment of that study. If you had you would have found that when relevant confounders like altitude, poverty and home ownership are included there is not statistically significiant relation of ADHD prevalence with CWF. I demonstrated this in my article ADHD linked to elevation not fluoridation. Coincidentally, the importance of altitude was confirmed in another study which you completely ignore. That study is:

Huber, R. S., Kim, T.-S., Kim, N., Kuykendall, M. D., Sherwood, S. N., Renshaw, P. F., & Kondo, D. G. (2015). Association Between Altitude and Regional Variation of ADHD in Youth. Journal of Attention Disorders.

Unfortunately, the scientific literature is full os such inadequate studies where confounding factors are ignored. Great for confirming biases but, by themselves, absolutely useless if we want to get to the truth.

Peckham et al., (2015) is another example you use. They claimed a relationship of hypothyroidism with CWF but refused to include iodine deficiency (a well established cause of hypothyroidism) in their statistical analysis.

Studies from areas of endemic fluorosis

You extract a lot of mileage out of the studies by Xiang and his coauthors (eg Xiang et al., 2003) – and they are probably the better studies in your collection. But even here your confirmation bias leads you to draw unwarranted conclusions. I showed this in my articles Connett fiddles the data on fluorideConnett & Hirzy do a shonky risk assesment for fluoride and Connett misrepresents the fluoride and IQ data yet again.

For example you claim (correctly) that Xiang found a statistically significant correlation of IQ with urinary fluoride. But a dispassionate consideration of the data shows this relationship explains only 3% of the variance in IQ. I suggest to you that inclusion of some relevant confounders in the statistical analysis would probably cause the correlation with urinary fluoride to be non-significant. This parallels the situation reported by Malin and Till (2015) for ADHD (and here they were able to explain over 20% of the variance in prevalence of ADHD by fluoride – before inclusion of confounders like elevation when the explanatory power of fluoride disappeared).

You have from time to time acknowledged the poor quality of the reports you rely on regarding fluoride and IQ but have said that “there must be something in it” because there are so many reports. There may well “be something in it” but you will not make progress by jumping to your ideologically motivated conclusions favouring chemical toxicity. Just think about it. Those studies occurred in areas of endemic fluorosis – where skeletal fluorosis and severe dental fluorosis are common. It is reasonable to expect such disfiguring and disabling diseases may impact the quality of life, learning ability and IQ of inhabitants. I suggested this mechanism for explaining the data in my article Severe dental fluorosis and cognitive deficits.

CWF is never used in areas of endemic fluorosis so such an effect on cognitive abilities would not occur. And that is consistent with the existing studies which do not show and IQ deficits resulting from CWF (see, for example, Broadbent et al., 2014 and my article IQ not influenced by water fluoridation).

Paul, you are disingenuous to pose the question in your presentations:

“What primary studies (not self-serving government reviews) can you cite that allow you to confidently ignore or dismiss all the evidence of fluoride’s potential to damage the brain?”

We must remember that this is posed in the context of your campaign against CWF and there is no primary study, or review, indicating “potential damage to the brain” from CWF. When you assert “Over 300 studies have found that fluoride is a neurotoxin” you are relying on animal studies where high concentrations of fluoride were used and poor quality studies from areas of endemic fluorosis. None of the studies you rely on are relevant to CWF. It is simply unprofessional scaremongering to promote these sort of political messages:

neurotoxin

Scaremongering slide from Connett’s 2016 New Zealand presentation

I demonstrated in my article Approaching scientific literature sensibly how such uncritical dredging of the literature is meaningless. A Google Scholar search for  produced 2,190,000 results for water toxicity but only 234,000 for fluoride toxicity. So let’s paraphrase your question:

“What primary studies (not self-serving government reviews) can you cite that allow you to confidently ignore or dismiss all the evidence of  water’s potential to damage the body?”

Misrepresentation of evidence supporting CWF

Randomised control trials

Again you raise the red herring of the lack of randomised controlled trials (RTCs) showing CWF effective. As I pointed out to you in our 2013/21014 debate  there is also a lack of RTCs showing CWF not effective – and that must surely tell you something. Simply there are no RTCFs on the subject (although there are on other forms of fluoride delivery like fluoridated milk – see Stephen et al., 1984).

The fact is that such trials are practically impossible with social health measures like CWF. The American Academy of Pediatrics comments in their article on the Cochrane Fluoridation Review:

“it would be a logistical nightmare to try creating a public water system that pumps fluoridated water to the first house on the block, delivers non-fluoridated water to the following two houses and then provides fluoridated water to the 4th and final house on that block.”

This was acknowledged by the Cochrane Reviewers in their discussion. Your mate, and fellow member of the Fluoride Action Network leading body, Bill Osmunson, argues that such an RTC is possible. But his description of how it would be setup shows he is not really serious. He suggests that housing developments be built with several different water reticulation systems and houses be attached to these different systems by flipping coins!

There are some areas of investigation, such as drug efficacy, where RTCs are possible and ethical – but social health measures like CWF is not one of them. That does not prevent an objective analysis of all others sorts of investigation and data which enables health authorities and decision makers to make reliable decisions on such issues.

The Cochrane Fluoridation Review

Paul, I am shocked that with your scientific training you resort to a complete misrepresentation of the recent Cochrane Fluoridation Review (Iheozor-Ejiofor et al., 2015):

Cochrane 1

Connett misrepresented the findings of the Cochrane Fluoridation Review in his 2016 New Zealand presentations

Surely you are not that naive? The reviewers had selection criteria for inclusion of studies in their calculations. This excluded most modern cross-sectional  studies – on the basis of unavailability of data before CWF was started – not quality as you imply. Those restrictions meant they were unable to draw conclusions on the factors  in your slide – but they were discussed, and the studies cited, in the discussion section of the review. These non-selected studies do show that CWF is beneficial to adults (Griffin et al., 2007Slade et al., 2013), provides benefits even when fluoridated toothpaste is considered (see Water fluoridation effective – new study and Blinkhorn et al., 2015) and reduces social inequalities (Riley et al., 1999). The research also shows tooth decay increases when CWF is stopped (see Fluoridation cessation studies reviewed – overall increase in tooth decay noted and Mclaren & Singhal 2016).

How is it that you ignore the language in the review referring to limitations imposed by its selection criteria and then present their qualified conclusions as if they were facts. Can you not understand sentences like?:

“Around 70% of these studies were conducted before 1975. Other, more recent studies comparing fluoridated and non-fluoridated communities have been conducted.We excluded them from our review because they did not carry out initial surveys of tooth decay levels around the time fluoridation started so were unable to evaluate changes in those levels since then.”

Why did you persistently ignore the qualifications in their conclusions imposed by their selection criteria expressed in the common phrase?

“We found insufficient information . . . “

And, why did you purposely ignore the specific conclusion:

“Our review found that water fluoridation is effective at reducing levels of tooth decay among children. The introduction of water fluoridation resulted in children having 35% fewer decayed, missing and filled baby teeth and 26% fewer decayed, missing and filled permanent teeth.We also found that fluoridation led to a 15%increase in children with no decay in their baby teeth and a 14%increase in children with no decay in their permanent teeth.”

Yes, that was followed by the disclaimer “These results are based predominantly on old studies and may not be applicable today.” But that only means the reviewers could not draw specific conclusions about today because they had excluded modern studies.

You have purposely ignored the issues around study selection and presented their inability to draw conclusions as evidence that there is no effect. That is not a scientific assessment of the review – it is a blatantly propagandist exercise in cherry picking motivated by an ideological position. An exercise in public relations, not proper scientific assessment.

Topical vs systemic

I think one change that did come out of our debate is that you now tend to qualify you claims about the systemic and topical roles of fluoride in preventing tooth decay. You use words like “primary” and “predominantly.” But you still confuse the issue by arguing that topical action is quite separate from ingestion when you ask”

“If fluoride works primarily on the outside of the tooth why swallow it?”

The fact is that fluoride, calcium and phosphorus in dental plaque and saliva (to which the CDC attributes the topical action of decay prevention) occur through ingestion of these nutrients in food and water. It is naive to separate the reaction at the tooth surface from ingestion of food and beverage.

You also ignore completely the evidence that ingested fluoride plays a beneficial systemic role with developing and so far unerupted teeth (see Ingested fluoride is beneficial to dental health and Cho et al., 2014).

And let’s not forget about our bones which benefits from appropriate amounts of fluoride in our diet (see Is fluoride an essential dietary mineral? and  Yiming Li et al., 2001)

Use of PR techniques – You are the guilty party

I have shown here how you have distorted and misrepresented the science around CWF. In doing so you are behaving as an ideologically driven lobbyist – not an objective scientist. You are not intelligently and critically assessing the scientific literature – you are cherry-picking and selectively quoting to promote your own agenda.

Personally, I think this sort of behaviour is unethical for a scientist. Sure, we all have our biases and beliefs and this can influence our interpretation of the literature. But you are consistently misrepresenting the science – and continue to do so even after you have been shown wrong.

Perhaps this is unsurprising considering you are essentially a political lobbyist campaigning against a social health policy. You lead a lobby organisation – the Fluoride Action Network. This organisation receives finance from the “natural”/alternative health industry – most publicly from Mercola. According to tax returns you and other members of your family, personally receive monthly payments from these funds.

It hypocritical for you, then, to disparage honest scientists and their publications in the way you have done regarding the Hastings project. Your bias (and refusal to deal with the science) comes out in your description of scientific reviews and papers as “dummy reviews,” “bogus,” “self-serving government reviews,” etc.

In one of your final slides you claim the alleged PR tactics by scientists:

“Would not be necessary if science was on the promoters’ side – but it is not.”

In fact, it is you that are on the wrong side of the science and that is why you resort to misrepresentation, distortion, fear mongering and slander.

You also claim:

“After 6 years there has been no detailed or documented response to our book The Case Against Fluoride.”

And

“Proponents will very seldom agree to publicly debate either myself or other leading opponents of fluoridation.”

Yet, isn’t that exactly what I did in our Fluoride Debate of 2013/2014? And didn’t I give a platform on my blog for you to make all your points and to present the arguments from your book?

And isn’t it a fact that in most forums where your lobby against CWF you, in fact, lose because the scientific arguments against you prevail? You make a big thing of every single victory you achieve against CWF but are silent about the larger number of losses.

As we are discussing the refusal to debate let’s be honest. Your organisations, internationally and locally, attempt to prevent supporters of science from involvement in their discussion forums. I personally have been banned from all local anti-fluoride forums and from the Fluoride Action Networks Facebook forum.

This suggests to me that neither you nor your supporters are willing to take part in a good-faith discussion of the science around CWF. You are simply behaving like a political and commercial lobbyist – not a scientist for whom such discussion should be welcome.

Nevertheless, once again I offer you a right of reply to my comments in this article. In fact, I would happily welcome such a reply as this would be in the best traditions and interests of the science.

References

I have included only citations where links were not available.

Ludwig, T. G. (1958). The Hastings Fluoridation project I. Dental effects between 1954 and 1957. New Zealand Dental Journal, 54, 165–172.

Ludwig, T. G. (1959). The Hastings fluoridation project: II. Dental effects between 1954 and 1959. New Zealand Dental Journal, 55, 176–179.

Ludwig, T. G. (1962). The Hastings fluoridation project III-Dental effects between 1954 and 1961. New Zealand Dental Journal, 58, 22–24.

Ludwig, T. . (1963). Recent marine soils and resistance to dental caries . Australian Dental Journal, 109–113.

Ludwig, T. G. (1965). The Hastings fluoridation project V- Dental effects between 1954 and 1964. New Zealand Dental Journal, 61, 175–179.

Ludwig, T. G. (1971). Hastings fluoridation project VI-Dental effects between 1954 and 1970. New Zealand Dental Journal, 67, 155–160.

Ludwig, T. G.; Healy, W. B.; Losee, F. L. (1960). An association between dental caries and certain soil conditions in New Zealand. Nature, 4726, 695–696.

Ludwig, T.G.; Healy, W. B. (1962). The production and composition of vegetables in home gardens at Napier and Hastings. New Zealand Dental Journal, 58, 229–233.

Ludwig, T.G.; Pearce, E. I. F. (1963). The Hastings fluoridation project IV – Dental effects between 1954 and 1963. New Zealand Dental Journal, 59, 298–301.

Xiang, Q; Liang, Y; Chen, L; Wang, C; Chen, B; Chen, X; Zhouc, M. (2003). Effect of fluoride in drinking water on children’s intelligence. Fluoride, 36(2), 84–94.

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Are you really right?

Great explanation of our different thinking processes by Julia Galef. Readers who listen to the Rationally Speaking podcast will recognise her.

She describes the two different mindsets we have when approaching problems – calling them the “Warrior mindset” and the “Scout mindset. Motivated reasoning which is so widespread is a strong feature of the “Warrior mindset.” While this may spur people to action it is not a good way of solving problems.

I like the way Julia brings out the fundamental role of emotions in determining mindsets – and the way different people approach problems.

So some good advice from her is to encourage emotions related to curiosity, the desire to understand and the ability to be proud about changing one’s mind and not defensive about retaining beliefs.

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June ’16 – NZ blogs sitemeter ranking

 

Blog June

There are about 300 blogs on the list, although I am weeding out those which are no longer active or have removed public access to sitemeters. (Let me know if I weed out yours by mistake or get your stats wrong).

Every month I get queries from people wanting their own blog included. I encourage and am happy to respond to queries but have prepared a list of frequently asked questions (FAQs) people can check out. Have a look at NZ Blog Rankings FAQ. This is particularly helpful to those wondering how to set up sitemeters. Please note, the system is automatic and relies on blogs having sitemeters which allow public access to the stats.

Here are the rankings of New Zealand blogs with publicly available statistics for June 2016. Ranking is by visit numbers. I have listed the blogs in the table below, together with monthly visits and page view numbers. Meanwhile, I am still keen to hear of any other blogs with publicly available sitemeter or visitor stats that I have missed. Contact me if you know of any or wish help adding publicly available stats to your bog.

You can see data for previous months at Blog Ranks

Subscribe to NZ Blog Rankings Subscribe to NZ blog rankings by Email Find out how to get Subscription & email updates Continue reading

A cynical take on effective speakers

This video is a parody of a TED talk – you know, those talks which often come across very impressively but may not have much in the way of real content.

Or is this just me getting cynical in my dotage? I certainly feel I have an excuse for that.

Source: This Parody Of Every TED Talk Ever Is Absolutely Perfect – Digg

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Richard Dawkins – speech to Reason Rally, 2016

This was Richard Dawkins’ speech to the 20116 Reason Rally in Washington DC last week.

Richard suffered a mild stroke earlier this year and this video shows he is still not fully well. Anyway, too unwell to travel so he presented the speech as a video.

There is nothing new here – he has made all these points before. But these points are well worth repeating, and he makes them so well.

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Chemophobic scaremongering: Much ado about absolutely nothing

much-ado

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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Fluoridation: News media should check press releases from anti-fluoridationists

A recent ruling from the New Zealand Press Council warns against news media  publishing press releases from biased groups without providing context or seeking comment from any other party. The ruling resulted from a complaint  by Toi Te Ora Public Health Service against the coverage of the fluoridation issue by The Whakatane Beacon. For the full ruling see Source: TOI TE ORA PUBLIC HEALTH SERVICE AGAINST WHAKATANE BEACON.

Specifically, the ruling relates to two articles:

  • “Dentist group dispels dire warning message” provided by Stan Litras, spokesman for Fluoride Information Network for Dentists (an anti-fluoridation group). It asserted the Bay of Plenty DHB claims that increased tooth decay would result from removal of fluoride were not supported by reliable metadata studies.
  • “No Fluoride commonsense to campaigner” gave the views of Jon Burness, Fluoride Free Whakatane spokesman. He claimed reports that Ministry of Health figures show no justification for adding fluoride.

The Press council concludes:

“Importantly both published articles were effectively press releases from interest groups with a particular point of view. As the Council has had cause to comment in two recently upheld complaints (Cases 2478 and 2483) running a press release, without seeking comment from any other party, does not make for a balanced piece of journalism. There are significant dangers in simply regurgitating a Press Release and it does not accord with best journalistic practice unless it is clearly spelt out as a Press Release.”

Media should be wary of misrepresentation

Stan Litras’s press release criticised evidence used by Dr de Wit from the District Health Board and medical officer of Health. It misrepresented de Wet, yet the newspaper failed to put the criticisms and allegations to him. The Press council described this as “a simple failure of journalistic principles.” It added that it “is the obligation of the publication to allow an individual to comment if mentioned or quoted indirectly in an article.”

The Press Council made a similar observation with Jon Burgess’s press release, pointing out that the claims in the article were not put to the Ministry of Health (whose data Burgess was misrepresenting). The council put this specific complaint to one side as it did not have a direct complaint from the Ministry. It did comment, though, “that again this was not the best journalistic practice.”

Anti-fluoridation groups like Litras’s  Fluoride Information Network of Dentists (an astroturf group for Fluoride Free New Zealand) are constantly providing press releases misrepresenting studies and experts. These manufactured press releases are circulated within the international anti-fluoride network and the tame websites and magazines run by the “natural”/alternative health industry. Occasionally they end up being published in more reputable mainstream media outlets where they can do more damage.

It would be nice to think the mainstream news media was sufficiently responsible to actually check out the claims being made by such obviously biased groups. It seems a simple principle to actually check with the experts or organisation whose data is being used in the press release (the Whakatane Beacon slipped up there). But it would also be nice to think that responsible news media attempts to provide balance when they are producing articles critical of scientific findings – even when provided by a maverick scientist into self-promotion. It surely doesn’t take much to work out which expert or institution should be asked for a balancing viewpoint.

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May ’16 – NZ blogs sitemeter ranking

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Image credit: Blogging Discussion with Students 

There are about 300 blogs on the list, although I am weeding out those which are no longer active or have removed public access to sitemeters. (Let me know if I weed out yours by mistake or get your stats wrong).

Every month I get queries from people wanting their own blog included. I encourage and am happy to respond to queries but have prepared a list of frequently asked questions (FAQs) people can check out. Have a look at NZ Blog Rankings FAQ. This is particularly helpful to those wondering how to set up sitemeters. Please note, the system is automatic and relies on blogs having sitemeters which allow public access to the stats.

Here are the rankings of New Zealand blogs with publicly available statistics for May 2016. Ranking is by visit numbers. I have listed the blogs in the table below, together with monthly visits and page view numbers. Meanwhile, I am still keen to hear of any other blogs with publicly available sitemeter or visitor stats that I have missed. Contact me if you know of any or wish help adding publicly available stats to your bog.

You can see data for previous months at Blog Ranks

Subscribe to NZ Blog Rankings Subscribe to NZ blog rankings by Email Find out how to get Subscription & email updates Continue reading

New review shows clear economic benefits from community water fluoridation

Sapere

The NZ Ministry of Health has released a new review of the benefits and costs of water fluoridation in New Zealand.* Unlike most reviews I have discussed here dealing with the scientific aspects, the authors of this review say:

“we take an economist’s perspective; we look at the national cost-effectiveness and cost-benefit of fluoridation, and comment briefly on disparities.”

This perspective is, of course, important to the Ministry of Health which must invest its resources efficiently. These considerations were the prime reason the Ministry commissioned the review from the Sapere Research Group.

Readers who want to read the full report (78 pages) can download it from the link – Review of the Benefits and Costs of Water Fluoridation in New Zealand (pdf, 818 KB).

Strong evidence for benefits

The review points out that oral health is still a major issue for New Zealand. Despite considerable improvement over the last 20 to 30 years, “New Zealand remains a relatively high-caries population:”

“The ‘burden’ of the disease from dental decay is equivalent to three-quarters that of prostate cancer, and two-fifths that of breast cancer in New Zealand.”

It finds strong evidence for the benefits of community water fluoridation (CWF):

“A large body of epidemiological evidence over 60 years, including thorough systematic reviews, confirms water fluoridation prevents and reduces dental decay across the lifespan. The evidence for this benefit is found in numerous New Zealand and international studies and reports.”

Its estimates of the benefits of CWF include:

  • “In children and adolescents, a 40 percent lower lifetime incidence of dental decay (on average) for those living in areas with water fluoridation.”
  • “For adults, a 21 percent reduction in dental decay for those aged 18 to 44 years and a 30 percent reduction for those aged 45+ (as measured by tooth surfaces affected).”
  • “48 percent reduction in hospital admissions for treatment of tooth decay, for children up the age of four years.”

The review expresses this cost-saving in material terms:

“We estimate the 20-year discounted net saving of water fluoridation to be $334 per person, made up of $42 for the cost of fluoridation and $376 savings in reduced dental care. In short, there is a 9 times payoff; adjusting the discount rate from 3.5 percent to 8 percent results in a 7 times payoff.”

This estimate is “robust to significant changes in assumptions.” In fact, their “assumptions around dental costs avoided are likely to be at the lower end of what patients face.”

Quality of life benefits

Not surprisingly the review finds significant benefits of CWF to the quality of life estimates.  Interestingly, it makes the point that while most other health interventions require net health spending, the CWF benefits to quality of life arise from net cost-saving because the savings from reduced need for dental treatments are far greater than the costs of fluoridation.

I can understand the need for economists to quantify the quality of life returns on investment but can not, for the life of me, understand how they can take into account the pain and misery of children who suffer from poor dental health. The review does mention an Oral Health Impact profile which attempts to measure “patient discontent from pain, dry mouth and chewing problems.” But I suspect this goes only a short way to quantifying the personal and subjective problems arising from poor dental health.

In particular, I am thinking of the psychological and physical medium and long-term effects. Poor dental health negatively impacts the child’s schooling and must contribute to learning difficulties. This, in turn, will mean childhood poor dental health reduces a person’s future prospects in employment, adult education, social and personal relationships and general happiness.

Conclusion

The benefits of CWF are clear when considered in financial and economic terms and this new review presents these in a clear and convincing way. It will have an important  influence on the decision makers in the Ministry of Health, parliament and the government – especially as they discuss the new legislation required for the transfer of decision-making on fluoridation from councils to district health boards. But there are also personal and subjective benefits which are much harder to quantify to the satisfaction of economists and other bean counters. In the end, those personal and subjective benefits must bring a positive economic return to society as a whole, as well as the individual. If anything, decision makers and politicians should see that the case for CWF is even stronger than that made by the economic considerations in the review.

*Note: The Cabinet papers on the assessment of benefits from fluoridation and the upcoming legislative changes required to transfer decisions to District Health Board have also been released. These papers are very interesting and give an idea of the different factors the government has considered and the likely way the new legislation will go. I recommend any readers searching for more details on this to download the papers from this link:

DECISION-MAKING ON THE FLUORIDATION OF DRINKING-WATER SUPPLIES.

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Debating fluoridation and tyranny – Tom O’Connor responds

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Individual consent – what does it mean and how is it obtained?

This article below is a guest contribution from Tom O’Connor responding to my article Attempting a tyranny of the minority on fluoridation. I invited Tom to discuss the issue here, and offered him a right of reply because I think there is value in discussing the points he raised in his Timaru Courier opinion piece and  that I critiqued in my article.

Unfortunately, in this issue, the scientific arguments are very often a proxy for underlying values issues, at least on the part of opponents of fluoridation. It is in the nature of values issues that there is no “correct” answer (in contrast to arguments about facts). Nevertheless, the values issues are important so I hope they can be developed in discussion here around Tom’s original opinion piece and his response here. In the end, such issues are decided by democratic and political means so open discussion of the issues is important.


Firstly I am not opposed to the use of fluoride to combat tooth decay per se. Nor do I have any “anti-fluoride mates” as you put it. If the government wants to make fluoride freely available there are many ways of doing that without imposing it on everyone.

There are three main elements to the fluoride debate. The first is the efficacy or otherwise of fluoride as a preventative for tooth decay.

The second is the use of reticulated potable water as a means of delivering anything other than clean water to the community.

The third is the issue of mass medication, or mass treatment or mass therapy of people without individual consent and practical convenient and affordable alternatives. Legislating to declare a medical treatment is not a medical treatment simply on the ground that the dose rate is measured in parts per million is one of the most stupid and dishonest things I have ever seen any government do. Many medications are measured in such minute quantities.

The Grey Power Federation objection to the proposed addition of fluoride to potable reticulated water is based on the third element only. We do not have a policy in the first element simply because we do not have the expertise or scientific qualifications to develop such a policy. We have not considered the second element.

That policy has been, in my view, adequately explained in the Timaru Courier opinion piece you refer to. The following comments are therefore mine alone and do not necessarily reflect the opinion of Grey Power members or anyone else.

Efficacy

As you rightly point out there is probably nothing to be gained in participating in the endless argument between proponents and opponents of fluoride as an oral health treatment. Both sides have accused the other of engaging in pseudo-science and scare mongering. Both are, to some extent, probably accurate and in agreement on that point alone. However, where doubts exist, it is probably better to err on the side of caution.

Reticulated water

Territorial local authorities have the responsibility to provide potable water to their communities where no other sources are available or suitable. The principle responsibility of local authorities, as outlined in the Drinking Water Standards for New Zealand, administered by the Ministry of Health, is to ensure drinking water is as free from all other substances and organisms as possible. Using reticulated potable water to convey anything else, be it medical or not, is contrary to that principle.

The use of chlorine to remove micro-organisms and other pathogens is designed to remove unwanted and potentially unsafe matter from drinking. At the end of that process there is not supposed to be any detectable chlorine. That there often is demonstrates the difficulty of getting the addition of trace elements correct. That is a very different matter to the deliberate introduction of an additional substance which many people don’t want.

Mass treatment and individual consent

This is not the first time mass medication or treatment has been introduced in New Zealand. Iodine deficiency, as a cause for goitre, was discovered in the early 1900s and to address the problem table salt was iodised at up to 80mg of iodine per kilogram of salt in 1938. This was accompanied by an extensive public education programme and there was always un-iodised salt as a practical, convenient and affordable option on grocer shop shelves for those who did not want it.

Suggesting that those who object to fluoride in the water they pay their local authority to deliver can obtain alternative supplies from a community tap or buy it from the supermarket is unacceptable. These options are not possible, practical, convenient or affordable for many people.You may also recall a recent proposal to add folic acid to all bread products as a means of addressing a reproductive issue for women. The public outcry which saw that proposal dropped was not solely based on doubts about the efficacy of folic acid but the fact they many people simply did not want their bread medicated with anything for any reason.

You may also recall a recent proposal to add folic acid to all bread products as a means of addressing a reproductive issue for women. The public outcry which saw that proposal dropped was not solely based on doubts about the efficacy of folic acid but the fact they many people simply did not want their bread medicated with anything for any reason.

There are practical and cost effective methods of providing fluoride for those who want it. Forcing it on those who don’t want it is simply unacceptable in a free society.

Tom O’Connor


I will post a response to Tom’s arguments in a few days. Meanwhile, readers are welcome to make their own arguments in the comments section.

Ken Perrott

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