Anti-fluoridation campaigner, Stan Litras, misrepresents WHO

Stan Litras, Principal Dentist at Great Teeth, Wellington, and anti-fluoride activist but uses fluoride in his treatments

Wellington anti-fluoride campaigner, Stan Litras, has penned an “open letter” about community water fluoridation (CWF) to the Associate Minister of Health, Peter Dunne. He titles his document  HEALTH RISKS TO NEW ZEALANDERS FROM FLUORIDE) but, as we would expect, it is full of distortions and outright misrepresentations. (I have discussed some of Stan’s previous misrepresentations of the science of CWF in my articles:

• Dirty politics on the Royal Society fluoride review,
• The farce of a “sciency” anti-fluoride report,
• Cherry-picking and misinformation in Stan Litras’s anti-fluoride article,
• Fluoride Free NZ report disingenuous – conclusion,
• Misrepresentation of the new Cochrane fluoridation review, and
• Fluoridation is Safe and Effective).

A blatant  misrepresentation of WHO recommendations

I will just concentrate here on Stan’s whopper about the World Health Organisation’s (WHO) recommendations on the  of monitoring total fluoride intake for populations considering and implementing CWF. It is central to the recommendations he makes to Mr Dunne.

WHO does recommend monitoring the fluoride ingestion by a population before and after implementation of programmes for supplementing fluoride intake (eg., CWF, fluoridated salt and fluoridated milk). This is to make sure that fluoride intake is neither too low for providing dental benefits or too high when problems of dental fluorosis can occur. However, this following claim of Stan’s is just untrue:

“The World Health Organization strongly recommends that where health authorities implement water fluoridation, they must monitor total fluoride ingestion at the individual level. v

WHO notes that community level analysis is inadequate for assuring safety of all individuals.”

Let’s see what WHO actually recommends. Stan “cites” the WHO document “Basic Methods for Assessment of Renal Fluoride Excretion in Community Prevention Programmes for Oral Health,” to support these claims but he does not appear to have actually read the document.

Here is what the WHO document actually recommends:

“public health administrators should assess the total fluoride exposure of the population before introducing any additional fluoridation or supplementation programmes for caries prevention.”

It recognises that:

“Today, there are many sources of fluoride, and this needs to be taken into consideration when planning a community caries prevention programme using fluoride.”

And it concludes from the available research reviews that:

“at present, urine is the most useful biomarker of contemporary fluoride exposure.”

But notes its limitations – such as, the influence of diet (vegetables and meat influence the pH of urine and hence the degree of excretion of ingested fluoride through the urine), within-subject variation, lack of correlation between urinary fluoride excretion and fluoride intake and uncertainty about levels needed to give protection. It quotes the conclusion of Rugg-Gunn et al., (2011) in their book chapter “Contemporary biological markers of exposure to fluoride:”

“While fluoride concentrations in plasma, saliva and urine have some ability to predict fluoride exposure, present data are insufficient to recommend utilizing fluoride concentrations in these body fluids as biomarkers of contemporary fluoride exposure for individuals. Daily fluoride excretion in urine can be considered a useful biomarker of contemporary fluoride exposure for groups of people, and normal values have been published.” [My emphasis]

And then goes on to warn:

“Urinary fluoride excretion is not suitable for predicting fluoride intake for individuals.” [WHO’s emphasis]

This is the exact opposite of Stan Litras’s claim. The monitoring must be done at a group level – with proper care to make sure of random selection of people to sample. This publication provides lower and upper margins of optimal fluoride intake and the average daily fluoride excretion recommended for fluoride levels to be optimal.

Just to be clear – the limitations due to diet are not caused by the fluoride content of the foods but their different effects on urine pH and hence the excretion of fluoride in the urine. Random selection of people to sample allows these dietary variations to be averaged out for the group.

In fact, the WHO publication describes the methods for “studies” aimed at monitoring a population or group – not for monitoring individuals. So it does not support Litras’s recommendation that our public health system regularly monitor the fluoride level in individuals. And Stan’s claim that WHO asserts community level analysis is inadequate is completely false. It is, in fact, the individual level analysis that is inadequate.

Using “monitoring” to fear-monger

“Monitoring the fluoride levels in individuals” is central to Stan’s advice to Mr Dunne. He is just fear-mongering as this is neither necessary nor meaningful for the normal person. The before and after monitoring of groups recommended by WHO is simply to check if fluoride ingestion is inadequate before the introduction of fluoride supplement schemes like CWF – and to make sure that, after the introduction of the scheme, fluoride ingestion levels fall within the optimum range.

There is absolutely no suggestion by WHO that normal individuals should be regularly monitored for fluoride levels as Stan is recommending. He want’s to see this because it would cause unwarranted concern in the population.

Most at-risk individuals

While the WHO document recommends “priority is given to children of the
younger ages because of their susceptibility to enamel fluorosis” it does recognise a value in monitoring some adults. For example:

“adults, exposed to fluoride in certain industries (for instance aluminium production, addition of fluoride to water, salt or milk, or exposed to drinking water with excessively high fluoride concentrations).”

These are not normal members of the population – but the increased risk of exposure resulting from their professions could warrant some sort of regular testing regime. I compare this to the monitoring of people working with ionising radiation sources like X-ray machines or handling radioactive isotopes. The wearing of radiation detection badges and regular blood testing is warranted for these people – where it is not for the ordinary person in the street who is exposed just to background radiation and the occasional X-ray.

I imagine, then, that regular individual monitoring could be advisable for water treatment staff handling fluoridating chemicals – and dental technicians and practitioners who handle fluoride containing dental formulations such as varnish and filling materials.

A question to Stan Litras

I know for a fact that Stan Litras uses fluoride-containing dental formulations in his practice. Has he organised for regular testing of himself and his staff for possible fluoride contamination? Is he recommending that any of his patients treated with such material receive regular fluoride testing?

If not – why not?

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Fluoridation: Connett’s naive use of WHO data debunked

Paul Connett is the Executive Director of the anti-fluoride propagandists group, the Fluoridation Action Network (FAN). His recent presentation to the Denver Water Board’s fluoridation forum was full of scientific misrepresentations and distortions.

I debunked his claims on fluoridation and IQ in the article Connett misrepresents the fluoride and IQ data yet again. Here I debunk his claim that WHO data shows community water fluoridation (CWF) is not effective.

This video clip shows his claim:

1: Is there a difference between fluoridated and unfluoridated countries?

Connett waves around graphs showing declines in tooth decay in  some countries but does nothing to support his claim that there is no input from fluoridation to this improvement in oral health. After all, oral health depends on a number of factors so any serious claim needs adjustment for these factors and a proper quantitative comparison.

The data in these graphs is just not suitable for this – but lets humour people like Connett who place so much faith in the graphs. I took this graph from Connett’s book The Case against Fluoride (Chapter 6, page 38).

It is easy enough to do a ballpark comparison of the average rate of decline of dental decay  for the four nonfluoridated countries and compare that to the average rate for the four fluoridated countries. I did this and found the average decline in dmft (decayed, missing and filled teeth) for non-fluoridated countries was 1.4/decade and for fluoridated countries 1.6/decade. On the face of it the decline in tooth decay was more rapid in the fluoridated countries – the opposite to Connett’s claim.

Of course, Connett would laugh at such a comparison and claim the data is just not good enough to make such comparisons.  And I agree – but isn’t that exactly what he was trying to do?

He was simply waiving around a poor set of data which he thinks supports his claim that CWF is ineffective – it doesn’t. He should know that, and he should be ashamed, as someone with scientific training, to make these claims using such evidence.

The huge influence of inter-country differences on these data, irrespective of fluoridation, surely sticks out like a sore thumb in Connett’s graphs. That doesn’t require a scientific training to see. These differences introduce so much noise into the data that no conclusion is possible about the influence on fluoridation.

Robyn Whyman pointed this out in his report for the National Fluoridation Information Service – “Does delayed tooth eruption negate the effect of water fluoridation?“:

“Studies that appropriately compare the effectiveness of water fluoridation do not compare poorly controlled inter-country population samples. They generally compare age, sex, and where possible ethnicity matched groups from similar areas. 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.”

2: Comparison within countries

The WHO data includes New Zealand and Ireland where there are fluoridated and unfluoridated areas. Cornett’s graphs do not differentiate – the just use the averages for these two countries.  Yet, even that sparse WHO data set  shows clear benefits of community water fluoridation on oral health. Consider the differences in tooth decay between fluoridated and unfluoridated areas of  Ireland.

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!

The data in the graphs below shows a similar situation for New Zealand – this time using data from the NZ Ministry of Health (which is much more extensive than the WHO data).

3: CWF still effective when fluoridated toothpaste used.

Paul Connett’s claim that CWF is unnecessary when fluoridated toothpaste is used was based on a naive interpretation of the graphs he was waving around. The data above for Ireland and New Zealand show that, even where the use of fluoridated toothpaste is widespread, there is still a difference in the oral health of children living in fluoridated and unfluoridated areas of a country.

Other research also shows CWF is still effective, even though its effectiveness may, these days, be less than observed in the past when fluoridated toothpaste was not used. But, in contrast to what Connett appears to think, fluoridated toothpaste in not the only factor involved. There is the general improvement in dental health treatments and diet in recent years. Rugg-Gunn & Do (2012)  also refer to the “halo” effect – a diffusion of beneficial fluoride from fluoridated area into unfluoridated areas via food and beverages and consumption of water away from the place of residence.

The recent data can also be influenced by differences in residence and place of dental treatment. For example, dental treatment and record taking may occur at a school or dental clinic in a non-fluoridated area but the child may live in a fluoridated area. This effect could explain the apparent reduction of differences for New Zealand children from fluoridated and non-fluoridated areas after 2006 in the above graph. In 2004 a “hub and spoke” dental clinics system was introduced where one school dental clinic could serve several areas – both fluoridated and non-fluoridated.

 

Conclusion

Paul Connett’s use of the graphs showing improvement in oral health in countries independent of fluoridation, is on the surface, naive because no conclusion about the effectiveness of CWF can be drawn from this sparse data involving comparison between countries with so many political, social and environmental differences. Connett is presumably aware of this, and of the fact the same WHO data shows a beneficial effect for Ireland and New Zealand.

This is another case of Connett using a scientific academic title (his PhD), to give “authority” to his misrepresentation and distortion of the science to local body politicians.

References

Connett, P., Beck, J., & Micklem, H. S. (2010). The Case against Fluoride: How Hazardous Waste Ended Up in Our Drinking Water and the Bad Science and Powerful Politics That Keep It There.

Ministry of Health (2014) Age 5 and Year 8 oral health data from the Community Oral Health Service.

National Fluoridation Information Service (2011): Does Delayed Tooth Eruption Negate The Effect of Water Fluoridation? National Fluoridation Information Service Advisory June 2011, Wellington, New Zealand.

Rugg-Gunn, A. J., & Do, L. (2012). Effectiveness of water fluoridation in caries prevention. Community Dentistry and Oral Epidemiology, 40, 55–64.