Author: Kenneth L. Mitchell, BEng, HDip, MSc CEng, MIEI At a glance, the debate on water fluoridation appears pretty one-sided. In one corner, we have national and international researchers, dentists and public health experts. In the other, we have libertarians, alternative health practitioners and conspiracy theorists. Yet recently, five councils have passed motions calling for the forty-year practice to end. Why? For a start, these motions were preceded by one-sided presentations by the anti-fluoridation lobby with little or no factual or scientific input. As engineers, we are taught to ignore reputations and look at the evidence. It was with this in mind that I decided to take a look at the issue and the claims of the anti-fluoridation lobby.

The facts about fluoride

Fluoride is a natural mineral found in water and fluoridation is the addition of it to the optimal recommended level for the prevention of dental caries (tooth decay). It began in Ireland in 1964, costs approximately €3.86 million (2011) and it is added at the rate of 0.8 ppm (parts per million). The World Health Organization recommends 1ppm and the EU specifies no more than 1.5mg/L. There has been a wealth of peer-reviewed research into water fluoridation, both internationally and nationally, and they overwhelmingly show massive dental-health benefits. Surveys to measure effectiveness are conducted on a regular basis in Ireland and all of these show a substantial benefit, with up to a massive 63% decrease in primary cavities when compared to Northern Ireland. The research put forward from the anti side is either non-peer reviewed ‘junk’ pseudoscience or involves extremely high doses of fluoride. This is not representative of the Irish situation or community fluoridation schemes in general. The US National Academy of Sciences and the World Health Organization both list fluoride as one of the trace elements "considered essential for human health and metabolism". Like all chemicals (including water), fluoride is poisonous in large amounts but, similarly to salt. It is beneficial in small amounts and does not accumulate in the body. A lethal dose of fluoride would require a 70kg man to consume 350ltrs of 1ppm fluoridated water in one sitting. Claims that the fluoridation chemical hydrofluorosilicic acid (HFSA) is an industrial ‘waste’ product has no basis in logic. It is a side-product, as alcohol is a side product of yeast fermentation or, indeed, as oxygen is a side product of photosynthesis. This point is moot, however, because we do not use HFSA in Ireland; we use fluorosilicic acid mined directly from a raw material source, the mineral fluorospar. Legally, the Irish Supreme Court has ruled that water fluoridation is constitutional and the EU Commission has stated that it does not have any difficulty in law with the practice. The Irish Dental Association strongly supports the policy of fluoridation in Ireland as an essential element of oral health policy. The World Health Organization and the US Centers for Disease Control have recognised water fluoridation as one of ten great public-health achievements of the 20th century. Some 25 countries fluoridate for 377 million people, including the United States, Australia, Japan, United Kingdom, Spain, New Zealand, Canada and Ireland. Twenty-eight countries (such as Denmark and Italy) have a natural optimum level of fluoride in their water (280 million). Due to the large number of separate water sources, countries such as Switzerland, France and Germany utilise salt fluoridation. Milk (UHT) fluoridation is used widely in Chile, Peru, Russia and parts of China and Scandinavian countries give dental fluoride rinses yearly to improve oral health.

Mass medication and cost effectiveness

FluorideThe argument that fluoridation is mass medication is more a philosophical debate. Technically, it is described as ‘mineralisation’ and has been described as similar to adding vitamin D to milk or folic acid to cereals. It should also be noted that other chemicals such as chlorine are added to water for its anti-microbiological effect. Calls for ‘pure, chemical-free’ water show a misunderstanding of water chemistry as a chemical-free product. A chemical-free product could make you sick, as it would be loaded with bacteria from the old pipes – and, indeed, completely unmineralised water has a leaching effect, which would remove nutrients from your body and food if consumed and/or used. Another more philosophical argument is that we should instead use the approximately €4 million to educate and encourage more people to brush their teeth more often, but the obvious question is would it be as cost effective? The fact remains that Ireland is amongst the worst countries in Europe for high-frequency consumption of sweets by children; therefore the use of fluoridated toothpastes alone is insufficient to prevent tooth decay. It is estimated that, if water fluoridation stopped, the nation's dental health would deteriorate over time to the point where the average five-year old could expect to have four to five more decayed, missing or filled teeth. There is statistical evidence that water fluoridation may have particular advantages for persons on lower income in Ireland.

Dental fluorosis

[caption id="attachment_18578" align="aligncenter" width="558"]Flourosis An example of moderate dental fluorosis[/caption] There is only one rare side effect of water fluoridation; mild dental fluorosis. Dental fluorosis is a cosmetic condition; it has no health consequences (Irish Medicines Board) and, as the graph below indicates, the majority of cases of dental fluorosis are not caused by water fluoridation. At the levels at which fluoride is present in Ireland's water supplies (0.6 - 0.8ppm), any occurrence of dental fluorosis is only detectable by a dentist as faint white flecks on the surface of teeth. One of the most recent arguments put forward by the anti-lobby is that infant formula should not be made using fluoridated water due an increased risk of developing mild dental fluorosis in babies that are 100% bottle fed. This appeal to ‘think of the children’ is Illogical, as most infants go onto other foods at six months and when on a rare occasion dental fluorosis is discovered with an infant, it is on the minor end of the scale. The Food Safety Authority in Ireland and the Irish Government’s Expert Body on Fluoridation advise that there is no significant evidence of any adverse effects to the health of infants consuming infant formula made up with fluoridated tap water. They add, “It is not recommended that people switch from using tap water to bottled water to make up infant formula.” The Centers for Disease Control in the United States takes a slightly different stance, recommending, for peace of mind, to sometimes use unfluoridated water in preparing formula for 100% bottle-fed babies. This recommendation is not a warning – it is ‘peace of mind’ advice for concerned parents. The final anti-fluoride argument put forward is that fluoridation is a form of mind control and the example is given that fluoride was used by the Nazis to pacify prisoners in concentration camps. This theory has no basis in science and holocaust education groups call it a complete fabrication. [caption id="attachment_18579" align="aligncenter" width="375"]Oral health survey 2009 New Zealand Oral Health Survey - Baby Formula and Mind Control[/caption]


As I stated at the start of this article, these council motions were preceded by one-sided presentations by the anti-fluoridation lobby with little or no factual or scientific input. It is said that the scientist is constrained by reality, while the conspiracy theorist is constrained only by plausibility and their passion; this is a classic example of that. County councillors want to help people and like most people they can be swayed by a passionate truly held argument, notwithstanding those arguments being based on the facts and reality of the situation. This debate has served to highlight the need for councils to get factual advice on scientific issues, to do research, to talk to local science teachers or doctors or the relevant expert in the field. It has also encouraged those experts living in the community to contact their local representatives and offer to give advice on such complicated matters and this can only be a good thing. Kenneth Mitchell is a chartered engineer in the fields of chemical and environmental engineering. Email: References