28 February, 2021

The Rt Hon Jacinda Ardern
Prime Minister
Private Bag18 888
Parliament Buildings

By email only to:

Rt Hon Jacinda Ardern – Prime Minister

Copies to:
Hon Andrew Little – Minister of Health
Hon Peeni Henare – Associate Minister of Health
Ayesha Verrall – Associate Minister of Health
Dr Shane Reti – National Party Health
Dr Elizabeth Kerekere – Green Party Health
Brooke van Velden – Act Party Health
Debbie Ngarewa-Packer – Te Paati Maori Health


Dear Ms Ardern,

Regarding your announcement that Government is proceeding with the Health (Fluoridation of Drinking Water) Amendment Bill which seeks to amend Part 2A of the Health Act 1956.

Key considerations

  1. Ministry of Health advisors to Government on fluoridation have been overly influenced by the dental profession.
  1. According to a Ministry of Health response to me from an Official Information Act request for Ministry research on the whole-of-body effects (not just teeth) of ingesting fluoride little, if any, such work has been undertaken by the Ministry.
  1. So narrow is the Ministry’s view of fluoridation that the contract establishing the former National Fluoridation Information Service included a requirement that the NFIS  would “. . . not act in any way that may contradict or be inconsistent with Ministry policy on water fluoridation or with the MoH publication Good Oral Health for All, For Life” both of which unequivocally advocate fluoridation.
  1. When deciding to authorise district health boards to mandate adding to community water supplies what the US National Toxicology Program presumes to be a cognitive neurodevelopmental hazard to humans Government must be absolutely sure of all potential health consequences.
  1. Serious consideration must be given to the issues commented on below before the Health (Fluoridation of Drinking Water) Amendment Bill comes before Parliament for a third reading.
  1. The Health (Fluoridation of Drinking Water) Amendment Bill should be withdrawn pending an independent public enquiry, with evidence taken on oath, on the whole-of-body impacts of community water fluoridation on public health (not just teeth) with future Ministry of Health policy development on the issue based on the outcomes of the enquiry and its recommendations.


Currently before the New Zealand House of Representatives is the Health (Fluoridation of Drinking Water) Amendment Bill which seeks to amend Part 2A of the Health Act 1956 by empowering district health boards to direct territorial authorities to fluoridate or not fluoridate drinking water supplies in their areas.

When deciding whether to make a direction to fluoridate or not to fluoridate, DHBs would need to consider:

  • the scientific evidence about how the addition of fluoride to water affects the prevalence and severity of dental decay;
  • whether the benefits of adding fluoride outweigh the financial costs;
  • consider a population’s oral health status and population numbers (i.e. the total resident population which would receive water from the drinking-water supply); and
  • financial costs and savings, including ongoing maintenance and monitoring costs.

A local authority drinking-water supplier will have discretion to add fluoride to the water in the absence of a direction from a DHB on whether or not to fluoridate.

A local authority drinking-water supplier must comply with the direction of a DHB to fluoridate.

A local authority not complying with such a direction will be liable on conviction to a fine not exceeding $200,000 and, if the offence is a continuing one, to a further fine not exceeding $10,000 for every day or part of a day during which the offence continues.

DHBs will be given the authority to decide, at their discretion, whether or not specific water supplies should be considered for fluoridation.

The bill makes clear that local authorities would not be required to consult their communities about a DHB’s direction to fluoridate or its invitation to comment.

There is no provision in the bill for financial assistance to local authorities that receive a DHB direction to fluoridate.

Issues to consider 

A         Fluoridated water consumption 

In New Zealand water fluoridation is the process of adjusting the natural level of   fluoride in a community water supply to a concentration of between 0.7 ppm and 1.0 ppm.

This, however, is not a measure of doses (the actual amount of fluoride ingested on a daily basis by individuals) or dosages (i.e. doses divided by a persons’ body weight).

The Ministry of Health is unable to provide well researched statistical records for the full range of daily water ingestion, and thereby fluoride dose, by consumers of  fluoridated water in New Zealand, including specific ranges for infants and children   by age, labourers, athletes, and others such as those with diabetes, and those  encouraged by health professionals to use above average consumption of water for health or detoxifying purposes.

Neither can the Ministry provide evidence that the delivery of fluoridated water is safe at variable dose and dosage levels for lifetime consumption by all individuals without anticipated adverse health consequences.


B         Fluoride ingestion from all sources

Assessment of total fluoride intake is paramount in understanding the mechanisms of fluoride metabolism and therefore it is essential that fluoride values for beverages, water, and foods that are major fluoride contributors to fluoride intake are measured.

However, there does not appear to be a Ministry of Health comprehensive and nationally representative database of the fluoride concentration in foods and beverages consumed in New Zealand.

There is no advice publicly available on specific foods, beverages or produce that might contain significant concentrations  of fluoride (such as tea) that consumers may consider in either supplementing their daily exposures or restricting their daily exposures to fluoride


C         Assessing urinary fluoride levels before fluoridation programmes


In Basic methods for assessment of renal fluoride excretion in community prevention programmes for oral health, World Health Organisation, 2014, it is stated that ingested fluoride from all sources, whether deliberately or unintentionally ingested, is excreted primarily in the urine. Thus, studies of urinary fluoride levels are ideal for assessing the total intake of fluoride in populations and, more particularly, such studies also provide a basis for decisions on the use of fluoride for caries prevention.

The WHO report also clearly states that public health administrators should assess the total fluoride exposure of the population before introducing any additional fluoridation or supplementation programmes for caries prevention.               

There is no epidemiological research (with methodologies) undertaken by or for the Ministry of Health, using fluoride in urine as a biomarker, to determine current total levels of fluoride exposure in the New Zealand population which might influence Ministry advocated fluoride-based caries prevention programmes which comply with WHO advice.


D         Neurotoxicity and neurobehavioral effects

Grandjean and Landrigan in their paper ‘Neurobehavioural effects of developmental toxicity’ in the March 2014 issue of The Lancet stated that epidemiological studies since 2006 had identified fluoride as a developmental neurotoxicant i.e. a chemical that can injure the developing brain. They warned that untested chemicals should not be presumed to be safe to brain development and that      chemicals in existing use, like fluoride, and all new chemicals must therefore be tested for developmental neurotoxicity.

Choi et al. in their Environmental Health Perspectives paper Developmental Fluoride Neurotoxicity: A Systematic Review and Meta-Analysis report results that support the possibility of an adverse effect of high fluoride exposure on children’s neurodevelopment and that future research should include detailed individual-level information on prenatal exposure, neurobehavioral performance, and covariates for adjustment.

A 2017 study by Bashash et al. ‘Prenatal Fluoride Exposure and Cognitive Outcomes in Children at 4 and 6–12 Years of Age in Mexico’ published in the journal, Environmental Health Perspectives, by a team of investigators at the University of Toronto, McGill, the Harvard School of Public Health, and other institutions found an association between prenatal exposure to fluoride and cognitive  development disorders in children.

In this study, higher prenatal fluoride exposure, in the general range of  exposures reported for other general population samples of pregnant women and non-pregnant adults, was associated with lower scores on tests of cognitive function in the offspring at age 4 and 6–12 years.

The study’s findings, combined with evidence from existing animal and human studies, reinforce the need for additional research on potential adverse effects of fluoride, particularly in pregnant women and children, and to ensure that the benefits of population-level fluoride supplementation outweigh any potential risks.

A 2019 Canadian study (Till et al.) Fluoride exposure from infant formula and child IQ in a Canadian birth cohort is also very relevant.

Given the profound negative implications of such research for the welfare of New Zealand society as a whole the Ministry of Health must considered stopping all     current fluoridation measures in New Zealand at the very least as a precautionary measure


E         Endocrine systems and thyroid functions

The major National Research Council report Fluoride in Drinking Water: A Scientific Review of EPA’s Standards (2006), provided evidence that endocrine systems and   thyroid functions are impaired at exposure levels to fluoride below the consumption          levels expected from drinking what is described as optimally fluoridated water yet the Ministry of Health and district health boards (or fluoridated water system operators) have failed in their duty of care to inform fluoridated water consumers of contraindications when a direct water additive with such identified risks as fluoride is purposely added to a community water supply.

There is no evidence that the Ministry of Health or district health boards have provided the general public with clear warnings on the effect fluoride has on endocrine systems and thyroid functions.


F          Kidney patients and diabetics

 The major National Research Council report Fluoride in Drinking Water: A Scientific Review of EPA’s Standards (2006) says that kidney patients and diabetics are susceptible subpopulations that are particularly vulnerable to harm from ingested fluorides. This statement was relevant to fluoridated water as low as 1ppm concentration.

The U.S. National Kidney Foundation says that kidney patients should be notified of the potential risk of fluoride exposures.

There is no indication of how the Ministry of Health and district health boards intend to fund filtering devices for susceptible individuals as a precautionary measure if widespread implementation of an enacted Health (Fluoridation of Drinking Water)         Amendment Bill increases the number of susceptible individuals by thousands.

Regarding kidney function, an August, 2019 study, ‘Fluoride exposure and kidney and liver function among adolescents in the United States: NHANES, 2013– 2016’ published in the journal Environment International found that fluoride exposure may contribute to complex changes in kidney and liver related parameters among U.S. adolescents.


G         Pineal gland

The major National Research Council report Fluoride in Drinking Water: A Scientific Review of EPA’s Standards (2006) states that fluorides accumulate over time in the body’s pineal gland but at the time of the report whether fluoride exposure causes decreased nocturnal melatonin production or altered circadian rhythm of melatonin production in humans had not been investigated.

As a calcifying tissue that is exposed to a high volume of blood flow, the pineal gland is a major target for fluoride accumulation in humans with the calcified parts of the pineal gland containing the highest fluoride concentrations in the human body – higher than either bone or teeth.

The 2006 report did, however, state that fluoride is likely to cause decreased melatonin production and to have other effects on normal pineal function, which in turn could contribute to a variety of effects in humans.

A February 2021 paper in the journal Environmental Health, ‘Fluoride exposure and duration and quality of sleep in a Canadian population-based sample’ examined associations between fluoride exposure and sleep outcomes among older adolescents and adults in Canada and concluded that higher water fluoride concentration was significantly associated with increased risk of reporting fewer than the recommended hours of sleep.

This finding suggests that fluoride exposure may contribute to clinically meaningful reductions in sleep duration among individuals      living in areas with optimal water fluoridation.


H         Infant formula

The Ministry of Health states that typical fluoride intakes from formula feeding using fluoridated water at the levels of fluoridation used in New Zealand are safe, and there is no evidence of any adverse effects on infant health or child development.        

The Ministry quotes the 2014 Royal Society of New Zealand and Office of the Prime Minister’s Chief science Advisor review which concluded that there is no evidence that typical fluoride intakes from formula feeding, using optimally fluoridated water for reconstitution, has any adverse effects on infant health or child development aside from a possible greater risk of mild dental fluorosis.

Page 8 of that report, however, under ‘Fluoride exposure in specific population groups’ states  that infants 0-6 months of age who are exclusively fed   formula reconstituted with fluoridated water will have intakes at or exceeding the upper end of the recommended rangee (UL; 0.7 mg/day)


I           Alternatives to fluoridation

 Scotland’s Childsmile programme

The Childsmile core programme is available throughout Scotland with every child being provided with a dental pack containing a toothbrush, tube of 1000ppm fluoride toothpaste and an information leaflet on at least six occasions by the age of five. Children also receive a free-flow feeder cup by one year of age.

These are distributed in different ways in each health board area and every three- and four-year-old child attending nursery school is offered free, daily, supervised tooth brushing. This programme achieves higher child oral health standards than in fluoridated New Zealand communities.

There is a similar New Zealand example.

In 2015, Northland DHB dentist, Ellen Clark, set up a highly controlled tooth- brushing trial in Northland schools for her Master’s thesis in Public Health.

A teacher aide was paid to supervise tooth-brushing sessions, once a day for 170 children at Kaitaia Intermediate School.  Several other schools were selected as controls, all of them in areas of high deprivation, where children were given a toothbrush and fluoride toothpaste, but had no supervised brushing sessions at school. More than two-thirds of the children were Māori.

Ms Clark said she had hoped to improve the children’s oral health – but the results were far better than she dared to hope.

She said, “The children who were brushing (at school) had a mean number of 11.7 tooth surfaces that improved – that is, they remineralised or (the decay) reversed. In comparison, the kids who were not brushing had 8.6 tooth surfaces that deteriorated over the year which was quite profound, I wasn’t expecting that – I thought you’d have to follow these kids over several years before you saw such significant results.”

Supervision was critical, but the cost of a teacher aide, for an hour a day per school, was tiny compared to the potential savings in teeth and dollars said Ms Clark who added that such low-tech intervention could do the same for New Zealand, at a relatively low cost.


Silver diamine fluoride

Silver Diamine fluoride is a topical medication used to slow down or stop dental    decay in primary and permanent teeth. The colourless liquid contains both silver, which has antibacterial properties, and fluoride, which has the ability to re-mineralise damaged tooth enamel. Together, silver and fluoride can be used to stop the progression of tooth decay and stabilize the tooth until a dentist determines further dental treatment is needed.

The topical medication became available in the United States in 2014 when it was approved by the U.S. Food and Drug Administration to be used as a desensitizing agent, paving the way for its introduction to the U.S. dental market.

The main advantages of SDF include its ability to kill cariogenic bacteria, to provide caries arrest without requiring the use of local anaesthesia or caries excavation and to promote remineralization. (See January 2018 issue of the Journal of the California Dental Association.)

Amelogenin-Derived Peptide

 Research published in March 2018 shows that a product including peptides  made from amelogenin, a protein involved with the development of enamel on teeth, can naturally protect teeth and if used daily is a way of preventing decay.

The study, ‘Biomimetic Tooth Repair: Amelogenin-Derived Peptide Enables in Vitro Remineralization of Human Enamel’, is published in the journal ACS Biomaterials Science and Engineering.

Researchers tested six different treatments for repairing teeth but only the peptide-alone sample resulted in remineralization resembling the structure of   healthy enamel. Other treatments like fluoride provided some mineral growth but not enough to be classified as healthy enamel.

The study lead author said that treatment could be provided either over the counter or in clinical settings and that remineralization guided by peptides is a healthy alternative to current dental health care.

Researchers behind the study suggested that peptide-based treatments can be used in toothpastes and gels as a part of a daily treatment and that such preventative care should be safe for people of all ages.

No analyses of these alternative dental heath treatments have been forthcoming from the Ministry of Health.


J          Industrial fluoride by-products

The New Zealand Institute of Chemistry in an undated paper titled Hydrofluorosilicic  Acid and Water Fluoridation states that three chemicals are in common use for the purpose of community water fluoridation in New Zealand, namely, sodium fluoride, sodium fluorosilicate and hydrofluorosilicic acid (HFA).

All manufacturers of superphosphate produce hydrofluorosilicic acid as a by-product and in the New Plymouth works of Farmers Fertiliser Ltd the scrubbing process has been modified to produce an acid used for water fluoridation. The process removes fluoride from the gas stream, “thus preventing an environmental hazard”.

HFA is very corrosive to most metals but demand in the North Island is sufficient to justify economic recovery.

The Ministry of Health and its district health board agencies have repeatedly claimed that community water fluoridation is safe.

The Water New Zealand Code of Practice – Fluoridation of Drinking- Water Supplies in New Zealand, First Edition, December 2014, states that a   drinking water supplier should ensure that a chemical supplier has a quality assurance system for the supply and delivery of any fluoridating agent to ensure its chemical purity, safe delivery and use and that a quality assurance system should be    implemented to manage all the factors associated with the specification, contract management, supply (including transportation), purity, storage, use and handling of fluoride compounds that could adversely impact upon the health and safety of staff,       contractors and consumers.

There does not appear to be any fully detailed documentation that the Ministry of Health has commissioned analysis of the chemical composition of all fluoridation products (from all sources) added to community water supplies in New Zealand, with special reference to hydrofluorosilicic acid, and for the purpose of determining absolute consumer safety.


K         Processing food with fluoridated water

You have previously been in Europe, which is largely fluoride free, for the prime purpose of initiating negotiations on free trade between New Zealand and European countries.

Exposure to fluoride has increased considerably over several decades

Including from foods processed with fluoridated water. It can be assumed therefore, that food exported from New Zealand might contain fluoride residue at varying concentrations.

The Ministry of Foreign Affairs and Trade and the Ministry of Business, Innovation and Employment must be made fully aware of the implications for exports to fluoride free nations before enacting the Health (Fluoridation of Drinking Water) Amendment Bill an outcome of which has the potential to significantly increase the volume of food processed with fluoridated water.     


L          Sugar in the diet                

The United Kingdom government has introduced a Soft Drinks Industry Levy which combined with Public Health England’s Change4Life campaign reminds parents that sugary drinks, including juice drinks, energy drinks, cola and other fizzy drinks, are one of the main sources of sugar in children’s diets.

Consuming too much sugar is one of the leading causes of tooth decay and childhood obesity. Tooth decay can be prevented by cutting down on sugar as well as brushing teeth twice a day.

Neither the Ministry of Health nor district health boards are undertaking on-going advertising campaigns on the bad oral health effects of sugar and sugary drinks.


M         Benefits and costs of nation-wide fluoridation

The 2015 Sapere report, Review of the benefits and costs of water fluoridation in New Zealand, prepared for the Ministry of Health, is deficient in many respects in providing plausible estimates of the benefits and costs of implementing nation-wide fluoridation.

For example, Sapere understood that the 2009 New Zealand Oral Health Survey provided the most reliable estimate of the impact of water fluoridation on oral health and reported that a clinical examination of 987 children aged 2 to 17 years showed a 40 percent reduction in dental decay. Sapere ignored the fact that the report itself clearly states that this survey was not designed as an in-depth fluoridation study.

It is, however, interesting to note from an Official Information Act disclosure of that data that at ages 16 and 17, of the 52 fluoridated children surveyed the average decayed, missing or filled teeth (dmft) was 2.46 and of the 55 non-fluoridated children the average dmft was lower at 2.39.

The latest oral health statistics from the New Zealand school dental service for 12-year-olds (2019) show statistically insignificant differences between fluoridated and non-fluoridated cohorts.

The 28,349 children fluoridated were 70.21 per cent caries free with a mean of 0.65 decayed missing or filled teeth (dmft) and the 23,129 non-fluoridated children 66.44 per cent caries free with a mean of 0.77 dmft. That is, less than four per cent difference in caries free and with decayed, missing or filled teeth the difference is less than one quarter of a tooth.

In citing a National Fluoridation Information Service report Sapere was probably unaware that the Ministry contract for that service, although having a laudable aim of maintaining an objective and credible viewpoint when reviewing literature and framing communications on water fluoridation, included a requirement that the NFIS would “not act in any way that may contradict or be inconsistent with Ministry policy on water fluoridation or with the MoH publication Good Oral Health for  All, For Life”  both of which unequivocally advocate fluoridation. (Service specification, clause 2.3)

Sapere omitted to cite Ko, L & Thiessen, K, A critique of recent economic evaluations of community water fluoridation, published in 2015 in the International Journal of Occupational and Environmental Health which concluded that recent economic evaluations contain defective estimations of both costs and benefits.

They say that incorrect handling of dental treatment costs and flawed estimates of effectiveness lead to overestimated benefits and that the real world costs to water treatment plants and communities are not reflected.   

The Health Select Committee noted that there is no provision in the Health (Fluoridation of Drinking Water) Amendment Bill for financial assistance to local authorities that receive a DHB direction to fluoridate and some members of the committee were concerned about an issue of moral hazard arising from district health   boards making a decision imposing costs on local authorities and ratepayers. The CH2M Beca Ltd report, Water Fluoridation Engineering Costs, prepared for the Ministry of Health, warned that with the cost estimates they had prepared it was important to appreciate that while a range of capital costs had been provided it was not broad enough to cover the situation for all plants in a particular size category and that for plants with little or no infrastructure, or supplies with multiple sources, the capital costs would be higher than their upper bound estimate.

Ancilliary requirements in addition to meeting capital supply requirements include water system and possible land purchase. Potential further requirements include training of operators, waste disposal, operating procedures//contingency plans, and increased monitoring and reporting.

Estimates of twenty year operating costs include fluoride chemicals, other required chemical additives, salaries, wages or contract charges, maintenance and depreciation.

Budget 2017 included provision of a token $12 million for assistance with the capital costs of fluoridation (note not ongoing operation and maintenance) to be allocated nation-wide in $3 million tranches over four budget years.

The committee failed to note another issue or moral cost hazard possibly arising for individuals whose health is negatively affected by fluoride in water and require the installation of expensive fluoride filters in their homes to maintain good health.

It will be ratepayers, while being shut out of any consultation process, who pick up the huge residual balance of capital costs and all ongoing cost of , operation and maintenance.


N         Cart before the horse

 In reporting back to Parliament on the Health (Fluoridation of Drinking Water)  Amendment Bill Parliament’s Health Select Committee, while stating that medical and dental associations and representative bodies, and most doctors and dentists, spoke in support of fluoridation, the committee acknowledged that the majority of  submitters expressed concern about the safety and efficacy of the practice. Many of those concerned submitters were highly qualified doctors and dentists.

However, the committee considered safety and efficacy issues beyond the subject matter of the Bill which it determined to be strictly about giving district health boards the power to direct local authorities on fluoridation.

A more rational approach, surely, would be to determine safety and efficacy before determining means of delivery.

When a mass public health intervention such as community water fluoridation is applied to everybody, the burden of evidence to know that people are likely to benefit and not to be harmed is very high since people can’t choose on the basis of informed consent.


A strong case can be made for the Health (Fluoridation of Drinking    Water) Amendment Bill to be withdrawn pending an independent public enquiry, with evidence taken on oath, on the whole-of-body impacts of community water fluoridation on public health (not just teeth) with future Ministry of Health policy development on the issue based on the outcomes of the enquiry and its recommendations.

Given recent fluoride research the Ministry of Health cannot continue to rely on the August 2014 report Health Effects of Water Fluoridation: A Review of the   Scientific Evidence published on behalf of the Royal Society of New Zealand and the Office of the Prime Minister’s Chief Science Advisor.

This report cites little research showing adverse health effects from fluoride in spite of the fact that considerable evidence on these effects was provided to the Royal Society in 2012.

The intriguing back story on the contrived council and Ministry of Health funded Royal Society/Gluckman report on fluoridation is available online.


O         The precautionary principle

 The precautionary principle states that if an action or policy has a suspected risk of causing harm to the public domain (affecting general health or the environment globally), the action should not be taken in the  absence of scientific near-certainty about its safety.

Under these conditions, the burden of proof about absence of harm falls on those proposing an action, not those opposing it.

The precautionary principle is intended to deal with uncertainty and risk in cases where the absence of evidence or the incompleteness of scientific knowledge carries potentially serious implications for society. (See: Taleb et al., The         Precautionary Principle: Fragility and Black Swans from Policy Actions, University of East Anglia, 2014)

With reference to the issues considered above it is clear that the Ministry of Health has not abided by this principle and is unable to provide any high quality evidence that there is scientific near-certainty about the safety of community fluoridated water to all consumers.


P         Conclusion

The U.S. Centers for Disease Control and Prevention has acknowledged that the mechanism of fluoride’s benefits are mainly topical, not systemic. There is no need, therefore, to swallow fluoride to protect teeth.

Since the purported benefit of fluoride is topical and the risks are systemic it makes more sense to deliver the fluoride directly to the tooth in the form of toothpaste. (See: I – Alternatives to fluoridation above). Since swallowing fluoride is unnecessary, and potentially dangerous, there is no justification for forcing people (hundreds of thousands supposedly against their will) to ingest fluoride through their water supply.

Trevor Sheldon, who chaired the advisory group for the systematic review on the effects of water fluoridation commonly known as the York Review 2000 (published in the British Medical Journal) says that if fluoridation were to be submitted anew for approval today nobody would even think about it due to the shoddy evidence of effectiveness.

He also said that when a public health intervention is applied to everybody, the burden of evidence to know that people are likely to benefit and not to be harmed is much higher, since people can’t choose.

To obviate whole-of-body health risks and significant misallocation of           public health funds and local government revenue a moral and sensible       decision by Government would be to withdraw the Health (Fluoridation of            Drinking Water) Amendment Bill from the parliamentary order paper.


Yours sincerely,

Ross Forbes