We have all experienced this problem. Claims made on the internet which rely on nothing more than constant assertion – and moving on, when challenged, to new claims, similarly relying only on assertion. The old Gish gallop.
The conscientious defender of science is often loaded down with the task of checking out claims, finding the literature – and reading it to find what it actually says. So it is useful, when there is a debate on a specific subject, to have access to a source where all the claims are considered together.
Community water fluoridation is one subject where all sorts of weird and wonderful (and unscientific) claims are peddled. Now we have a document which critically analyses many of these claims in one place. What’s more – it is in a peer-reviewed publication. And it is local – dealing with common claims made by anti-fluoridation campaigners in New Zealand.
The paper is:
Broadbent, J., Wills, R., McMillan, J., Drummond, B., & Whyman, R. (2015). Evaluation of evidence behind some recent claims against community water fluoridation in New Zealand. Journal of the Royal Society of New Zealand, 6758(October), 1–18.
Unfortunately, it is behind a pay wall – but many readers may have institutional access – or know someone who has.
I am not going to go through the whole paper here – nor present the analysis of each claim ( I have already done this for many common anti-fluoride claims – interested readers can do a topic search here, or browse the fluoridation list of articles). Instead, I list below all the claims considered in the paper below
Chemistry of fluoride
Claim: ‘[F]luorine is an inherently toxic element’ (Gross 1956; Atkin 2013).
Claim: ‘Fluorine naturally presents as calcium fluoride in water supplies’ (Guha 2011; Atkin 2013).
Claim: ‘Water fluoridation systems use either hydrofluorosilicic acid or derivative hexafluorosilicate. These compounds have never been tested for human health safety’ (Waugh 2012; Atkin 2013).
Claim: ‘Silicofluorides do not fully dissociate to form free fluoride ions in aqueous solution and revert to the silicofluoride ion in acid stomach conditions’ (Atkin 2013; Sauerheber 2013).
Claim: ‘Silicofluorides do not completely dissociate to form free fluoride ions, as proved by Crosby (1969)’ (Royal 2010).
Claim: ‘The World Health Organization states that 40% of ingested fluoride is absorbed through the stomach wall as molecular hydrofluoric acid (a known mutagen). This negates the “all fluoride ions are the same” deception’ (Atkin 2013).
Health and safety
Claim: ‘In 2000, the US National Sanitation Foundation released test results showing fluoridation chemicals typically add 0.43 parts per billion (ppb) arsenic to the finished water’ (Connett 2001; Atkin 2013; Hirzy et al. 2013).
Claim: ‘Adjusting for NZ parameters, applying the EPA’s risk factor (3.5 × 10–5 deaths per 70 year lifetime per microgram arsenic per day), we would expect 1.1 extra lung and bladder cancer deaths per year in NZ due to the contaminated fluoridation chemicals used’ (Atkin 2013).
Claim: ‘A report by environmental risk consultant, Declan Waugh, showed that across all major health conditions, the 70%-fluoridated Republic of Ireland had significantly higher disease rates than never-fluoridated Northern Ireland, often by several 100%’ (Atkin 2013; Waugh 2013).
Claim: ‘The recent Harvard review of IQ studies found that there was a genuine concern about developmental neurotoxicity’ (Atkin 2013).
Claim: ‘In the US court case of Aitkenhead v Borough of West View it was found proven that fluoridation increased cancer rates by 5%. This finding has never been overturned’ (Atkin 2013).
Claim: ‘In 2006, Dr Elise Bassin published high quality research showing that boys (but not girls) exposed to fluoridated water between the ages of 5 and 10 had 500% more osteosarcoma in their teens (Bassin et al. 2006). No study has ever refuted Bassin’s findings, as they look at total lifetime exposure or exposure at time of diagnosis, both of which are irrelevant. This equates to two osteosarcoma deaths per year in New Zealand (NZ)’ (Atkin 2013).
Claim: ‘In 2006 Dr Elise Bassin published research in Cancer Causes and Control, demonstrating that it is likely that males exposed to fluoride, including fluoridated water, between the ages of 6 and 8 years inclusive, had at least a five-fold increased risk in developing osteosarcoma (bone cancer) in their teens’ (Atkin 2011).
Claim: ‘A range of studies, using different modalities, has shown a correlation between fluoride and heart disease’ (Takamori et al. 1956; Singh et al. 1961; Atkin 2013).
Claim: ‘[A] direct correlation [exists] between the fluoride level in arteries, including coronary arteries, and atherosclerosis’ (Li et al. 2012; Atkin 2013).
Claim: ‘Perhaps one of the most alarming potential consequences of water fluoridation, as highlighted in recent research, is that a significant correlation exists between fluoride uptake and calcification of the major arteries, including coronary arteries’ (Li et al. 2012; Waugh 2012).
Claim: ‘Following fluoridation’s introduction into the US, deaths from heart attacks sky-rocketed in the fluoridated communities, compared with non-fluoridated ones’ (Miller 1952; Atkin 2013).
Claim: ‘Between 1% and 3% of the population have a chemical intolerance to fluoride. This manifests in a range of conditions, including gastrointestinal problems and debilitating chronic fatigue’ (Feltman & Kosel 1961; Moolenberg 1987; Atkin 2013).
Claim: ‘In one study, which lasted 13 years, Feltman & Kosel (1961) showed that about 1% of patients given 1 mg of fluoride each day developed negative reactions, (Connett 2012).
Claim: ‘Research by the State University of New York in 2009 showed women in fluoridated communities had a 15% higher incidence of preterm births, and that this rate was greater for poor non-white mothers. Further research also shows higher preterm birth rates and lower birth weights connected with fluoride (Susheela et al. 2010). Based on NZ statistics, we would expect at least 3.3 extra neonatal deaths per year just from extra extreme preterm births caused by fluoridation, disproportionately affecting Maori and Pacific’ (Atkin 2013).
Claim: ‘Those whom fluoridation is claimed to most benefit, poor non-whites, not only receive little if any such benefit, as found by the York Review, but are most at risk from fluoride’s toxicity’ (Atkin 2013).
Research and mechanisms
Claim:‘The biggest reason [for reduction of dental caries] in New Zealand is that the Ministry of Health directed school dental nurses to stop filling teeth unnecessarily. They stopped filling tiny surface enamel defects during the Hastings experiment, producing an overnight 25% reduction in ‘decay’, attributed to fluoridation in the report (Colquhoun & Mann 1986). In 1976, they stopped drilling and filling perfectly healthy molars—a 64% reduction over five years’ (de Liefde 1998; Atkin 2013).
Claim: ‘The claimed reductions in decay [in the Hastings fluoridation trial], which were greatest for the younger children, were brought about partly if not mainly by a local change in diagnostic procedure following introduction of fluoridation’ (Colquhoun & Mann 1986).
Claim: ‘The original belief was that fluoride had to be ingested to harden teeth during enamel formation. This was discredited in 1999 (Featherstone 1999). Any significant effect from fluoride is topical, not systemic, through high fluoride concentrations (such as toothpaste), not through fluoridated water washing over the teeth during the day’ (Atkin 2013).
Note: Many of the claims considered are sourced from an article by Mark Atkins – formerly the “science and legal advisor” for Fluoride Free NZ. That article is:
Atkin, G. M. (2013). New Zealand drinking water should be fluoridated: No. Journal of Primary Healthcare, 5(4), 332–334.