This is Ken Perrott’s response to Paul Connett’s article Fluoride debate Part 1a – response: Connett
I think Paul’s response illustrates some of the problems in discussions of the fluoridation issue. He shows a selective approach to data, indulges in unwarranted extrapolation from research and misinterprets scientific knowledge to fit his own agenda. In the interests of maintaining interest by avoiding repetition, I will just select a few of the more obvious examples in my response.
It is pointless to continue debating definitions of fluoride as a medicine – as I have said the argument is largely semantic. people who wish to pursue the argument should do so in a court of law.
Irish oral health data.
Paul dismisses the data I presented showing the difference between fluoridated and unfluoridated areas in Ireland because he “would not exclude the researcher’s bias influencing the result!” That is an incredible statement because the source of the Irish data in my plot was exactly the same as that used in the plot of Cheng et al (2007) which Paul and many other campaigners against fluoridation constantly use to argue that fluoride does not contribute to the observed improvement of dental health!
In the figure below I have added the data for Ireland from Cheng et al’s diagram to illustrate this. Cheng et al used the mean WHO values for Ireland (the dotted line), (and only two data points for each country) while I simply used the data for both people from fluoridated and unfluoridated areas.
I am not impressed by Paul’s contradictory attitudes to the same data set. It displays a biased attitude driven by his wish to conclude that fluoridation has not had a beneficial effect on oral health.
I am also amazed that Paul should argue that with the Irish data it “would have been more impressive and more appropriate to have compared the health status of” the Republic of Ireland and Northern Ireland.
Surely comparison of the data from unfluoridated and fluoridated areas within a country introduces far fewer confounding factors than comparison of data for separate countries. History, culture, ethnic differences, differences in dental practice and assessments, and many other factors would contribute.
Paul shows some awareness of the problem of confounding factors when he refers to the noise in a large data set specifically in referring to Cheng et al’s original plots. Yet he seems to want to increase this noise, the influence of confounding factors, in the case of Ireland and rejects an example where confounding factors have been reduced. He then implies that it is the researchers who are “biased!”
The idea that somehow inter-country comparisons should have less noise than comparisons made within a country seems so obviously wrong to me I was pleased to find I am not the only person who sees this problem. Robyn Whyman in his report “Does delayed tooth eruption negate the effect of water fluoridation?“ puts it well:
“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.”
Contamination of fluorosilicic acid
Here Paul handed over to William Hirzy who rejected the data I presented for Hamilton city, NZ, as atypical – because the arsenic (As) concentration was so low.
See my article Anti-fluoridation study flawed – petition rejected for some background to Hirzy, his paper and the petition he organised. One of our commentors, Steve Slott, has brought to my attention that Hirzy is a “long time avowed antifluoridationist and is employed by Connett as the paid lobbyist for Connett’s antifluoridationist group, FAN.”
In the table below I include data from 2 other certificates of analysis – in these cases Australian produced material. I also include my own data from a batch I analysed about 10 years ago when I was researching the chemical. This suggests the Hamilton sample is not that atypical, for our region anyway.
Concentrations (ppm) of contaminants in several different batches of fluorosilicic acid
|Hamilton City**||Incitec 08||Incitec 09||Own
As you can see all the samples have a very low As concentration. Much lower than required by regulations for such materials used in water treatment. These samples do have a lot less As contamination than the ones Hirzy used in his study (typical value of 30 ppm). Maybe this represents the choice of samples in both cases, or maybe there are more sources of fluorosilicic acid in the US and some products have higher contamination of As. The fact that there are fewer plants producing fluorosilicic acid in New Zealand and Australia could be a reason for the apparently higher quality here.
I have no way of assessing the range of As contamination in US sourced samples so don’t know how representative Hirzy’s choices are. The NSF analyses water treatment chemicals and state in their last Fact Sheet on Fluoridation Products (2013) that only 43% of the fluoridation chemicals would have produced a detectable amount of As in the finished water (actually, because of the standard methods required – detectable in water at 10 times its maximum use level). The bar graph below shows the amounts of As measured in surveyed samples as a percentage of the USEPA regulated maximum contaminant level (MCL).
Similarly, Brown et al. (2004) (Trace contaminants in water treatment chemicals: sources and fate, American Water Works Association Journal. 96: 12, 111-125) identified the coagulation chemicals used in water treatment as far more likely to introduce contaminants than the fluoridation chemicals.
Hirzy may object because the NSF measured contaminants in terms of the finished water concentrations and not that in the concentrated chemicals. The finished water concentrations were then compared to the regulated MCL. But that will simply reflect his objection to the current MCL values.
This raises an interesting issue and identifies a problem with Hirzy’s approach in his campaign to substitute pharmaceutical grade NaF for fluorosilicic acid in water treatment. If the real issue for Hirzy was the As concentration he should instead have campaigned to lower the currently accepted regulations for level of contamination in fluoridation chemicals. Surely that would have satisfied his concern about the role of As in cancers – and possibly been more acceptable to authorities. If the current approved levels are too high let’s get them lowered – whatever chemical is used.
It is also interesting that the fluorosilicic acid used in Hamilton contained As contamination similar to those of the pharmaceutical grade NaF Hirzy used (typical value 0.76 ppm). He should be happy to advocate the use of material with our levels of purity in the US if his only concern is the As levels.
Perhaps we should be selling our fluorosilicic acid to the US if they cannot produce material to such standards.
Hirzy’s bandwagon is the possibility of cancers resulting from As in fluoridation chemicals. I appreciate where he is coming from and have no wish to debate that issue – it is outside my area of expertise. I can only comment that in our own situation (Hamilton City, NZ) the Waikato River source water has about 3 times the recommended maximum concentration of As for human consumption (see Hamilton – the water is the problem, not the fluoride!). This is reduced by about 80% during treatment but still remains a bigger source of As contamination than the fluoridation chemicals – by several orders of magnitude. it would be very silly to be concerned with contamination of the fluoridation chemicals and ignore the natural contamination of the source water.
Hirzy’s political activism
Finally Hirzy’s activist bias concerns me in that it could interfere with proper assessment of the risks. It certainly makes it difficult not to be suspicious about his claims. Out of hand he rejects the NSF conclusions as “a meaningless attempt at reassuring the public.” He also similarly rejects the conclusions of the NZ Water and Wastes Association as being “without merit.” This is derogatory to honest and active scientific and technical workers who have made the analyses, assessed the risks and drawn conclusions. Question the regulations if you must (and no regulations are permanent) but please do that using evidence, not by “poisoning the well” with such claims. Play the ball, not the man. Hirzy would object to his own work being flippantly rejected in such a way.
His use of the silly conspiracy theory that fluoridation is a way of disposing of industrial waste also raises questions of his credibility. And he is biased to claim that regulations have no “real value” because they were violated by one treatment plant!
Normal role of F in bioapatites
Paul seems to reject the concept that F is a normal constituent of apatites, including bioapatites. He argues that it is possible to have bones and teeth without fluoride. and says “that at the same level that fluorides interact with bioapatites it damages those bioapatites.”
But in the real, natural world, and not the extreme conditions of the laboratory, absolutely “pure” minerals don’t exist. Isomorphous substitution is normal and ubiquitous. Apatites only exist as end members like hydroxyapatite in unusual or laboratory situations. Fluoride and carbonate are very commonly incorporated into bioapatite by isomorphous substitution – as are some common cations.
In reality no bones or teeth are “fluoride free.” Which is just as well because they would have higher solubility and reduced strength and hardness. Sure, this might mean that it is normal for a proportion of people to have teeth with “questionable” or “very mild” forms of fluorosis. But that is a cosmetic issue (if at all noticeable) and does no harm. It has probably been a simple fact about our teeth through our whole evolution.
For the vast majority of people who have dental fluorosis (recognised by a professional) it is usually classified as “questionable” or “mild.” Real health concerns should only be raised for severe dental fluorosis. Yet anti-fluoride activists lump all those grades together and pretend that dental fluorosis is a much bigger problem than it really is.
We will deal with the mechanism of the beneficial role of fluoride on teeth in later articles so I will just respond briefly to Paul’s brief reference to the issue in his last article here. He claims the US Centers for Disease Control and Prevention (CDC) agrees “that the predominant benefit as far as protecting teeth is concerned is topical (rather than systemic).” (Actually, he says “concedes” and not “agrees” but this word is ideologically loaded). That is correct as far as it goes but we should remember that this is referring to existing teeth – ingested fluoride still has a beneficial role with bones and pre-erupted teeth. The word “predominant” is important. So I can’t help recognise the bait and switch tactic when, in his book, he drops the word “predominant” in his chapter summary and he says:
“For many years, fluoride was believed to act systemically to prevent caries— tooth decay—by being incorporated into the enamel of the developing teeth. However, it is now known to act topically—that is, at the surface of the tooth. Thus, the main reason for ingesting fluoride has disappeared . . .”
Again and again I find anti-fluoride people using this tactic to deny any mechanism but “topical.” They thereby purposely deny any of the known beneficial effects of ingested fluoride.
This bait and switch tactic is compounded by another bait and switch where the “topical” – referring to the reactions occurring at the tooth surface because of fluoride in saliva and biofilms – becomes a new “topical” – referring only to methods of application such as toothpaste and dentrifices. This tactic enables them to deny the beneficial roles of fluoride transferred from water to saliva during drinking, as well as that ingested.
Anti-fluoride activists pushed this misrepresentation hard during recent hearings on fluoridation at the Hamilton City Council in NZ. It had its effect when the Council took on itself to issue a leaflet giving oral health advice. This repeated the “topical” misinformation. Health and dental experts were publicly very critical of the leaflet and Hamiltonians felt embarrassed by the Council’s hubris.
Fluoridated toothpaste only complements, does not substitute for, this regular “top up” of saliva F during drinking and eating.
Perhaps we should be referring to “surface” mechanisms rather than “topical” ones as the latter is so easily seen as applying only to application methods.
Extrapolation from high concentration animal studies
I think Paul’s confidence in unsupported extrapolation from higher concentration animal studies is very cavalier. Paul claims:
“in the case of fluoride it is well know. That you have to give 5 to 10 times as much fluoride to rats to reach the same plasma level as you need in humans.”
The US National Research Council report “Fluoride in Drinking Water – A Scientific Review of EPA’s Standards“ discussed the contradictory data used for attempting to show a ratio between humans and rats for blood plasma levels and concluded:
“Dunipace et al. (1995) concluded that rats require about five times greater water concentrations than humans to reach the same plasma concentration. That factor appears uncertain, in part because the ratio can change with age or length of exposure. In addition, this approach compares water concentrations, not dose. Plasma levels can also vary considerably both between people and in the same person over time (Ekstrand 1978).”
I am suspicious of attempts to use comparison of blood plasma F levels for such justifications because of the huge range and variability of these levels. This sort of speculation seems to fuel the frequent use of the word “might” in Paul’s article (and attempts to convert such logical possibilities to realities) and in the end leads to the speculation being present as a fact (Paul’s “well-known” and the simple FANNZ declaration).
But Paul at least refers to one study on rats using drinking water with F concentrations closer to those of fluoridated water – Varner et al (1998). Unfortunately I could not get the full text of this paper and the link Paul provides to http://www.fluoride-journal.com does not allow access to mere mortals like me. In my search I was amazed how links promising full text of papers like this often just take one back to Fluoride Alert and their in-house interpretation.
The abstract mentions changes in cerebrovascular and neuronal integrity for AlF3, and to a smaller extent for NaF. As I can’t access the discussion to understand he possible significance of these small changes I won’t comment further on this.
Why do countries not fluoridate
Paul describes my consideration of the various reasons behind the decisions of countries not to fluoridate their community water supplies as “more like self-serving political spin than reality!” That is rather harsh – considering he then goes on to claim only 2 main reasons – freedom of choice and health concerns. Using his own article as a reference!
No, I won’t respond by selecting personal statement from citizens of the non-fluoridated countries as he asks. But here is an outline of the situation with fluoridation throughout the world taken from a recent issue of the newsletter of the New Zealand National Fluoride Information Service. It gives a pretty detailed picture:
Countries with widespread water fluoridation programmes include Australia, the United States of America, Canada, the United Kingdom, Ireland, Spain, Israel, Brazil, Brunei, Chile, Argentina, Colombia, Hong Kong, South Korea, Singapore and Malaysia. Countries with limited water fluoridation programmes include Vietnam, Fiji, Papua New Guinea, and South Korea.
Several countries are unable to introduce water fluoridation programmes due to technical, financial or sociocultural reasons. As an alternative, both salt and milk have been found to be reliable and convenient vehicles for increasing fluoride intake to an optimal level for hard to reach and low socio-economic communities. Studies have found them to be as effective as community water fluoridation schemes.
Some European, Latin American, and Caribbean countries, including France, Switzerland, Germany, Costa rica, Colombia and Jamaica currently use fluoridated salt schemes. Mexico and most Latin American and Caribbean countries (apart from Argentina, Brazil, Chile and French Guyana) have or have had salt fluoridation programmes.
A smaller number of countries currently have fluoridated milk programmes, including Bulgaria, Chile, China, Peru, Russia, Thailand and the United Kingdom
Some country regions have optimal amounts of naturally occurring fluoride which provides good protection for oral health. examples of countries supplied with naturally fluoridated water at or around the optimum level needed to prevent dental decay include the United Kingdom (estimated 329,000 people), United States of America (estimated 10,078,000 people) Canada (estimated 300,000 people) and Australia (estimated 144,000 people).
It is estimated that 39.5 million people around the world have access to naturally fluoridated water at the optimal level although variations from one community to another over time make it difficult to calculate an accurate total.
Reasons for not fluoridating water supplies and/or using alternative ways of overcoming fluoride deficiencies are simply not restricted to attitudes towards freedom of choice and health concerns, although they may have been deciding factors for a few countries. This is another instance where opponents of fluoridation are making widespread simplistic claims (like Europe bans use of fluorosilicic acid) based on only a few facts, and ignoring (or hiding) the details.
We should also remember that despite different decisions by governments and local authorities about implementation of fluoridation all the reputable national and international health bodies do accept the scientific consensus of the beneficial role of fluoride in oral health. It is this endorsement which is more relevant to us than the specific technical, political or social decisions made in other countries.
I am glad Paul rejects extremism among anti-fluoride activists. However this does not seem to stop him cooperating with extreme conspiracy theorists like Alex Jones and Vinny Eastwood to produce videos. (Have a look at Cyber bullying of science, which includes a recent video of Eastwood’s attacking scientists and science, to get an idea of how silly these people can be). People do notice such associations and draw their own conclusions. Paul appears to give some justification of “the more nutty conspiracy theories espoused by some opponents of fluoridation.” He says “promoters of fluoridation should not be surprised that some people are trying to come up with a rational explanation for why certain governments are behaving so irrationally promoting this practice.” Well that is his perspective and it is a minority one. I certainly don’t accept such justifications because I, and many others, have no trouble understanding the decisions to fluoridate.
Misrepresentation of the facts is a real problem among activists of all persuasions. That is understandable because ideological and political convictions and motivations can distract even the most honest people. Paul presents an example of an image that illustrates this for some supporters of fluoridation.
This image seemed to create a lot of controversy among local Facebook pages and I got the blame because it was posted on this blog. I have been assuring complainants that it is not my image and I do not support its implied message. It seems to have been taken from a document prepared under the Queensland Health logo. I cannot find a source and no-one seems to be able to give a citation. It is not on the Queensland Health web site. All Internet references seem to be in documents and sites of fluoridation opponents – indicating that it has backfired as a propaganda exercise for fluoridation. I gather it may have been prepared to send to selected Australian members of parliament at some stage.
Paul has sent me a copy of the document which interested readers can download.
But here is the trouble for those living in glasshouses who wish to throw stones. This sort of misrepresentation is probably more common among opponents of fluoridation. The figure below, for example, is from a document of the “Queenslanders for Safe Water” website which ironically included and criticised the Queensland Health photos! (Thanks to commenter Steve Slott for the link). It uses photos of extreme skeletal and dental fluorosis to argue against fluoridation.
This, and the Queensland Health photos, are extreme exaggerations used to promote a message. Reasonable people should condemn that tactic. But isn’t this, in essence, the same tactic used by Paul and other opponents of fluoridation when they extrapolate from animal studies at high concentrations, characterise the relatively common very mild and “questionable” cosmetic fluorosis as if it were severe, use the “topical” mechanism to argue that fluoridated water has no influence, wildly exaggerate the concentration of toxic contaminants in fluoridation chemicals, persistently and inappropriately describes fluoride a poison and a neurotoxin, misrepresent the reasons why some countries do not fluoridate their water supplies and deny data illustrating a beneficial effect of fluoride on oral health as “biased?”
Anyone wanting to follow the debate and/or check back over previous articles in the debate can find the list of articles at Fluoride Debate.