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FAQs and common misconceptions

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Is there a difference between "natural" fluoride and "artificial" fluoride? Is the fluoride ion the same?

Fluoride occurs naturally in a number of forms. In drinking water it is usually Calcium Fluoride.

The term "artificial fluorides" refers to the substances used in water fluoridation. These are silicofluorides, apart from a very few remaining plants using Sodium Fluoride. However Sodium Fluoride has been reclassified due to its use in weapons manufacture, and it no longer generally available.

Silicofluorides do not occur in nature.

The following table compares some properties of the relevant fluorides:

PropertyHFASodium silicofluorideCalcium fluoride
Classification Schedule 7 (dangerous poison) Schedule 6 (poison)Non-toxic
HazChem Class6 (acutely toxic ) & 8 (corrosive)6 (acutely toxic) & 9 (ecotoxic to vertebrates)None (non toxic)
LD5030 gm (4 tablespoons)4.9 – 8.75 gm (approx 2 – 4 teaspoons) 298 gm (about three cups, the same as table salt)

Note: LD50 is the single dose that kills 50% of those taking it. The figure is based on rat and mice studies, for a 70 kg adult. No one has deliberately given lethal doses to humans.

Note that it makes no difference if the substance is dilute or concentrated.

Fluoride ion.

When a substance is dissolved in water it largely breaks up into positively and negatively charged ions. However it can remain in a molecular form and still dissolve to some extent because of the bipolar charge on water molecules. But the more the substance breaks up into ions the better it dissolves.

The balance between the original molecular form of a substance and its ionic form in water is called the "dissociation constant".

Calcium Fluoride does not break up into ions very well, so it does not dissolve very well. But at 1ppm most if not all of the dissolved Calcium Fluoride has split up into Calcium ions and Fluoride ions. Silicofluorides are much more soluble than Calcium Fluoride, and ionise in a 2-stage process. However they do not completely break down into Fluoride ions. This was shown by Crosby in 1969. The dissociation was between 87% and 95%. Crosby is constantly misquoted as proving the dissociation was 100%, which is incorrect.

More importantly, all components remain available for chemical reaction, so whether the substance has fully ionised or not is in this respect irrelevant.

Further, when silicofluorides are put in acidic conditions, such as stomach acid, they tend to return to the molecular form (the dissociation constant shifts). According to WHO (2006) 50% of fluoride in the stomach is absorbed as molecular hydrofluoric acid, the most corrosive acid known, and which can attack DNA (i.e. is mutagenic/carcinogenic)

Research has shown that silicofluorides have some different biological effects on humans than either calcium fluoride or sodium fluoride. This relates to inhibition of the enzyme acetylcholinesterase(1), and the absorption of lead.(2)


1. "The Kinetics of Acetylcholinesterase Inhibition and the Influence of Fluoride and Fluoride Complexes on the Permeability of Erythrocyte Membranes"
Dissertation to receive Ph.D. in Chemistry from the University of Hamburg
By Johannes Westendorf Hamburg, Germany – 1975

2(a).Sawan et al "Fluoride increases lead concentrations in whole blood and in calcified tissues from lead-exposed rats" doi:10.1016/j.tox.2010.02.002
(b) Maas RP, Patch SC, Christian AM, Coplan MJ. "Effects of fluoridation and disinfection agent combinations on lead leaching from leaded-brass parts" Neurotoxicology 2007 28(5):1023-31.
(c) Masters R; Coplan "M Water treatment with silicofluorides and lead toxicity" International Journal of Environmental Studies Volume 56, Issue 4, 1999, Pages 435 - 449

You would have to drink 5000 glasses of water to die from fluoride poisoning (so fluoridation is perfectly safe).

This refers to the acute toxicity of fluoride, listed above. It is irrelevant to fluoridation, where the risk is long term exposure and accumulation in the body.

This can be compared with the Minimata Bay disaster in Japan, in the 1950s. No one could have eaten enough fish to drop dead instantly from methyl mercury poisoning, but 30 years of low level exposure and accumulation in the body made the inhabitants very ill, and some died.

Anyone who makes the statement above is misleading the public.

Water fluoridation is one of the top 10 public health achievements of the 20th Century

This statement was created by two dentists working for the Oral Health division of the US Centers for Disease Control and Prevention (CDC), one of the two main promoters of fluoridation. The DCD has refused all requests to substantiate this claim with scientific evidence.

The York Review found fluoridation safe and effective (15% reduction in tooth decay)

The York Review was a thorough systematic review of all population studies available. It was not allowed to look at laboratory studies, or at individual medical case histories.

A systematic review examines the methodology of research to determine the reliability. It then assesses the weight of evidence, and the reliability of that evidence, in relation to claims, in this case about safety and effectiveness.

It found that research was, overall, of poor to moderate quality. It rejected over 90% of studies as being too poor to consider further.

On the question of reducing tooth decay, it found a large variation in results, from the remaining 30 studies, all of poor to moderate quality – from 5% more tooth decay, many studies showing no difference, to a 64% benefit. The numeric median was 14.6% more caries-free children in the fluoridated area. But this cannot be legitimately claimed as a proven benefit. The report said:

"The quality … is in general only low to moderate, and should be interpreted with caution, especially considering the significant heterogeneity between studies."

This statement by the Chair of the advisory panel, Dr Trevor Sheldon, sums up the true findings of the York Review - that until better quality studies are available there will continue to be legitimate scientific controversy over water fluoridation.

By its very design, the York Review could never have determined safety of fluoridation - it was unable to examine a large portion of the evidence of adverse health effects. This issue was address six years later, by the US National Research Council Review.

The US National Research Council Review is not relevant to fluoridation

This is incorrect. First remember that risk is related to daily total intake (dose), NOT the concentration in the water supply. The Review's task was to assess the existing maximum allowable level of fluoride in the US, of 4ppm. However, some of the research reviewed showed harmful effects at the daily dose experienced by some people in communities fluoridated at around 1ppm. This was especially true of sub-groups of the population with high water intake. One of the panel members, environmental risk expert Dr Kathleen Theissen, has subsequently made it clear that the Review was relevant to fluoridation.

The Privy Council held in 1965 that fluoridation was not medication

This is incorrect. First, the Privy Council ruled on the Lewis case in 1964, not 1965.

The Privy Council ruled that:

The first point became obsolete in 2002, as the 2002 Local Government Act does not use the word "pure". Based on the Privy Council ruling, the new wording is more restrictive, in that it does not allow for additions to be made to the water to make it more "wholesome" in addition to making it safe to drink.

The second point is not a binding ruling, as it relates to a question of fact. The Privy Council's rulings are only binding on points of law. Any court can find that fluoridation is a health risk, and ban it on the basis.

The passage quoted in support of the claim is this:

"The addition of fluoride adds no impurity and the water remains not only water but pure water and it becomes greatly improved and still natural water containing no foreign elements."

However, this passage does not preclude fluoridation from being medication. Those who (mis)use this quote ignore the more relevant passages from the ruling. The Privy Council held that:

"The fluoridation plant is for the purpose of the supply of what might be termed 'medicated pure water' "
(confirming the NZ High Court statement by McGregor J), and then:
"Their Lordships think it an unnecessarily restrictive construction to hold (as did McGregor J.) that, because the supply of water was already pure there is no power to add to it constituents merely to provide medicated pure water, i.e. water to which an addition is made solely for the health of the consumers."

Is Fluoridation medication? Is it just like supplementing diet with iodine or iron?

Fluoride is not the same as iodine or vitamins. These are essential dietary elements, with a minimum required daily intake (RDI), below which clinical disease symptoms appear (e.g. goitre in the case of iodine). Fluoride is not a nutrient or essential mineral. There is no RDI for fluoride. No disease symptoms appear if fluoride is completely eliminated from the diet.

The NZ Medicines Act 1981 (sections 3(1)(a) and 4(a)) defines a medicine as follows:

"medicine means any substance … sold, or supplied wholly or principally - for administering to one or more human beings for a therapeutic purpose"
"Therapeutic purpose means - Treating or preventing disease"

The Ministry states that dental caries is a disease. Fluoridation is the supply of a substance (fluoride) to persons (entire communities) for the prevention of disease (dental caries). It is therefore medicine under the Medicines Act.

Are fluoridating agents are waste from the fertiliser industry, or manufactured specifically for fluoridation, to high quality standards?

Silicofluorides are not manufactured specifically for fluoridation. Hydrofluorosilicic Acid (HFA) is produced as a toxic waste in the wet scrubbing system located before the effluent stacks of the superphosphate industry, to prevent the very toxic gases (hydrogen fluoride and silicon tetrafluoride) escaping into the air, which is illegal. The liquor is allowed to settle so that any suspended solids fall to the bottom, and the clear liquid is sold as such for use in fluoridation. It is not made to "exacting standards of purity". There are three relevant standards:

Water treatment grade is not a Governmental or scientific standard. This allows significant levels of toxic heavy metals to be present:
Contaminant mg/kg
Antimony 148
Arsenic 495
Cadmium 148
Lead 495
Mercury 99
Nickel 990
Selenium 495

The only manufacturing process relates to Sodium Silicofluoride, where the still-contaminated HFA is mixed with caustic soda to produce the solid salt, used in dry-feeder type fluoridation plants.

The silicofluoride waste cannot be dumped directly in waterways, sea, or on land. The public water supply is a perfect way for fertiliser companies to dispose of their toxic waste – and be paid for doing so.

Was fluoride used by the Nazis and the Russians to make prisoners submissive?

Overall, the claims regarding this use of fluoride and fluoridation must be put in the "not proven" category; it remains speculative, as the claims cannot be documented, yet relate to scientifically demonstrated effects of higher doses of fluoride. The claim has no place in a scientific debate on fluoridation.

The only basis for this claim in relation to Nazi Germany is a letter by Charles Eliot Perkins, a researcher in chemistry, biochemistry, physiology and pathology. He claimed to be one of the scientists put in charge of the I G Farben industries shortly after WW2. I G Farben supplied the Nazis with war chemicals, munitions, etc. Perkins was supposedly informed that the German General Staff adopted the plan of using sodium fluoride to make prisoners-of-war more docile and easier to manipulate and control. There is no surviving evidence to suggest the Germans actually did this. It was also claimed that fluoride would reduce fertility, assisting population control as part of the eugenics programme begun in 1910 (by the Americans, but involving German scientists).

Dr Paul Connett, of Fluoride Action Network, confirms following a personal search to resolve this question that there is no documentary evidence of Perkins’ claims.

It is a fact that fluoride is a neurotoxin, and also that at sufficient doses reduces fertility. However, at this point there is no research to determine whether fluoride at the doses related to fluoridation of drinking water, would have the effects claimed by Perkins.

Perkins also claimed that the idea was taken up by the Russians, and fluoride was used in the Russian prison camps for tranquilisation of prisoners.

Use in Russian camps

This claim is also included in a statement by Oliver Kenneth Goff:

"I, Oliver Kenneth Goff, was a member of the Communist Party and the Young Communist League, from May 2, 1936, to October 9, 1939. My testimony before the Government is in Volume 9 of the Un-American Activities Report for 1939.
While a member of the Communist Party, I attended Communist training schools in New York and Wisconsin ... and we were trained in the revolutionary overthrow of the U.S. Government. ... We discussed quite thoroughly the fluoridation of water supplies and how we were using it in Russia as a tranquilizer in the prison camps. The leaders of our school felt that if it could be induced into the American water supply, it would bring about a spirit of lethargy in the nation, where it could keep the general public docile during a steady encroachment of Communism. "

There is also the statement of Major George Racey Jordan who was in charge of the shipment of sodium fluoride to Russia from Great Falls, Montana, via Alaska. He queried the shipment of considerable amounts of sodium fluoride to Russia and was told "frankly" that it was put into the drinking water in the prisoner-of-war camps to take away their will to resist.

Again, none of this appears to be corroborated.