Feature

Safe, simple and effective

Fluoridation of the water supply benefits the dental health of children and adults alike. So why has the history of this simple public health measure been one of ‘hurdles and delays’, asks John Beale

Fluoridation began on 25 January 1945 in Grand Rapids, Michigan. The level of fluoride in the water was adjusted to one part of fluoride to one million parts of water (1ppm). Six and a half years later, children aged between four and six had half the tooth decay of children in Muskegon, which had been used as a control.¹

Now, nearly 50 years later, more than 260 million people in over 40 countries, including the UK, drink fluoridated water.

There are over 100 studies on the dental effects of fluoridation published in scientific medical and dental journals. In addition there are countless hundreds of reports to government departments, local authorities and health boards across the world. These show an average reduction of between 40 and 60% in the number of decayed, missing or filled teeth.

The table below shows, for five-year-old children, the six best and six worst health districts in England and Wales together with their fluoridation status. Most studies have been carried out on children but it has also been shown that the benefits extend throughout adult life. As individuals get older their gums recede. Nowadays people keep their teeth for longer and ‘root caries’ is an increasing problem. Several studies have demonstrated that fluoridation is effective in reducing this condition.²

It is important to stress that behind all these figures fluoridation means less toothache, fewer extractions and fillings and a reduced need for general anaesthetics for many thousands of children.

There have been allegations that fluoridation can cause a variety of diseases ranging from cancer to allergic response. All these claims have been extensively tested. Whenever anything is accused of being harmful, further research must be done by research workers in that field and there must be careful examination of all the available evidence by expert groups. There may also be scrutiny by a court of law.

Water fluoridation has been subjected to all three of these methods. It would probably be true to say that more research has been conducted into the safety of fluoridation than any other public health measure.

In 1976 the Royal College of Physicians published a comprehensive review of the evidence on the medical aspects of fluoridation. It concluded that the consumption of water containing approximately 1ppm of fluoride is safe, irrespective of the hardness of the water.³

After further claims that fluoridation caused cancer the Department of Health established a working party to review all the available epidemiological evidence. This group, chaired by Professor Knox of Birmingham University, reported in 1985. It found nothing which could lead it to conclude that fluoride, either occurring naturally in water or added to water supplies, is capable of inducing cancer. The only contrary conclusions, it stated, are attributable to errors in data, errors in analytical technique or errors in scientific logic.⁴

Most recently the US Public Health Service established an ad hoc committee of experts to review the benefits and risks of fluoride. This committee published its report in 1991, confirming that there is no evidence of harm and recommending that the US Public Health Service should continue to support optimal fluoridation of drinking water.

Setting out the Public Health Service policy on fluoridation the assistant secretary for health and the surgeon general stated: ‘Whether one is rich or poor, a child at play or school, a busy adult, or a retired person, the benefits are gained simply by drinking fluoridated water or beverages prepared with fluoridated water. Nationally, the average annual fluoridation cost is only about 50 cents per person. The lifetime cost of fluoridation per person is approximately the same as the cost of one dental filling.’

In the UK some 6 million people drink fluoridated water. The Water (Fluoridation) Act 1985 (subsequently consolidated into the Water Industry Act 1991) provides the statutory basis for fluoridation. Prior to implementation the district health authority must undertake consultation locally. The community health council and local authority are asked for their views and members of the public are invited to write to the DHA.

In debates during such consultation, the different opinions are often presented as if they hold equal weight, as if the scientific arguments are between two groups of ‘experts’ who disagree. But at the end of a court case in which a Glaswegian pensioner sought an injunction to prevent Strathclyde Regional Council fluoridating the local water supply, Lord Jauncey said the principal witness against fluoridation ‘is undoubtedly a propagandist as well as a scientist’. He went on to say that he ‘was driven to the conclusion that he not infrequently allowed his hostility to fluoridation to obscure his scientific judgement’. The evidence of the pro-fluoride witnesses was ‘based on sound scientific principles’.

Fluoridation has widespread support from major medical and dental bodies throughout the world including the British Medical and Dental Associations, the Royal College of Surgeons, the Royal College of General Practitioners and the Institute of Cancer Research. It also has the support of the government and the opposition. Nationally a series of opinion polls conducted by NOP and Gallup have asked: ‘Do you think fluoride should be added to water if it can reduce tooth decay?’ The results have shown an increase from 66% of the public in favour in 1980 to 79% in favour in 1992.

Opponents sometimes claim that fluoridation is mass medication and is unethical because it infringes the right of individuals to decide whether they want it or not. Lord Avebury, chair of the Parliamentary Human Rights Committee, and a champion of the cause of individual freedom has pointed out that ‘fluoride is a natural constituent of water supplies. The adjustment of the quantity to an optimum level cannot be compared with the addition to water of a substance not found there ordinarily’. Professor John Harris of the Centre for Social Ethics and Policy at Manchester University said that fluoridation does not in any way conflict with basic human rights. There is, he said, no such thing as the right to drink fluoride-free water - only a personal preference to do so. If fluoridation is of benefit and is safe it could be said to be unethical not to fluoridate water where it is practicable to do so.

The history of fluoridation in Britain is one of hurdles and delays. Before 1974 the power to decide whether to introduce fluoridation lay with local authorities. Places such as Birmingham, Newcastle and Huddersfield started schemes in the mid to late 1960s. In 1974, area health authorities were given responsibility for fluoridation. These new authorities had many other issues to attend to and, apart from in the West Midlands, little progress was made.

The judge in the Strathclyde court case confirmed the benefits and safety of fluoridation but ruled that it had no legal basis unless Parliament specifically allowed it in clear and unambiguous terms. This led to the 1985 Act which gave the decision to district health authorities. During the preparation for the privatisation of the water authorities and in the early days of the new water companies no new schemes were introduced. But there is now a period of stability which has enabled health authorities to liaise once again with the water companies and engage in public consultation on fluoridation. Schemes are being considered in Yorkshire, Scotland, Hampshire and Northern Ireland.

In North Western region the water company is refusing to implement schemes requested by the health authorities (which also have to pay for fluoridation) on the basis that not all their consumers are in favour of it. There is a growing concern that Parliament could not have foreseen that the water companies would block fluoridation after the health authorities had decided on it. The general view at the time, reiterated by government ministers more recently, was that water companies would consider the technical feasibility, leaving the issue of medical effects and dental benefits, together with desirability, to health authorities. North West Water’s decision is therefore surprising and a cause for concern.

Lord Colwyn, who is also a practising dentist, summed up the argument in favour of fluoridation in a debate in the House of Lords: ‘It is all very well saying that they should clean their teeth and that we should take their sweets away from them. But it is not until you have had to hold down a screaming four-year-old child, anaesthetise it and pull out baby teeth that you realise the immorality of not initiating a proven, comprehensive plan that will prevent untold cases of future suffering’.