Fluoridation of the public piped water supplies is the safest, most effective and most efficient method of preventing tooth decay. By controlling the quality and the amounts of fluoride in the public water supply through technical means and under legal rules, the safety of everybody in the community is assured.

Over the past 30 years, the incidence of dental decay has declined considerably in Ireland and in other developed regions of the world. A major public health advance has been achieved. Most scientists agree that the reason for the improvement is fluoridation of public water supplies and the increased use of other fluoride products.

Water fluoridation is a low cost public health measure which is safe to human health and crosses social boundaries providing benefits equally to all sections of society, including both young and old and socially deprived.

Minor aesthetic effects result from excess fluoride exposure from all sources. These effects can be minimised by ensuring that fluoride levels are monitored carefully and kept within the statutory limit of 0.8 to 1.0 part per million and by ensuring that young children use toothpaste sparingly under the supervision of parents/carers.

Ongoing research being carried out in University College Cork and in Trinity College Dublin on behalf of the eight regional Health Boards and the Department of Health and Children will inform policy on the most appropriate use of fluoride for the future.

A Forum has been established by the Department of Health and Children which will review this research as well as the fluoridation of the public water supplies under the Health (Fluoridation of Water Supplies) Act 1960, (see the what's new section).

Why was water fluoridation introduced in Ireland?
The widespread availability of refined sugars in the mid 19th century led to an epidemic of dental disease (which has only recently come under control). To reduce levels of dental decay, the Irish Government in the 1960s decided to fluoridate public water supplies.

What are the effects of water fluoridation on general health?
Major reviews of the evidence by leading medical scientists have shown that the use of fluoride in drinking water at one part per million is safe to human health.

The Department of Health and Human Services in the United States carried out a comprehensive review of the benefits and potential health risks of fluoride and concluded that the practice of fluoridating community water supplies is safe and effective. The review found that there is no credible evidence linking the fluoridation of water at one part per million with cancer, kidney disease, immune defects, reproductive problems, genotoxicity, stomach ailments and bone fractures.

The World Health Organisation, The Centres for Disease Control and Prevention in Atlanta, USA, The Royal College of Physicians London, The Royal College of Physicians of Ireland, and many other authoritative bodies support these findings.

In countries with unusually high levels of fluoride at ten parts per million or higher in drinking water, skeletal fluorosis is a significant public health problem.

What about the allegations being made against water fluoridation?
Allegations have been made against water fluoridation since it was introduced in Ireland in the 60s.

The current debate is only taking place here after almost 40 years of water fluoridation.

Similar debates have taken place in other countries that have adopted water fluoridation, for example, the United States, Canada, Australia, New Zealand and the United Kingdom - countries which have decided to retain their water fluoridation programmes.

Much of the present debate seems to have spilled over from the debate in the United Kingdom where the authorities are making preparations to extend water fluoridation to other regions in the United Kingdom.

What are the side effects of water fluoridation?
A side effect of water fluoridation is dental fluorosis. However, the type of fluorosis produced by water fluoridation at one part per million is almost undetectable to the untrained eye.

More severe forms of fluorosis are most definitely caused by young children swallowing too much fluoride toothpaste.

Children under six years of age should be supervised when brushing and should only use a small pea-sized amount of toothpaste. All parents should be aware of this.

How does fluoride prevent tooth decay?
Fluoride in the diet through fluoridated tap water ensures a constant optimal level of fluoride in the body. This enhanced, beneficial fluoride level in the saliva ensures the greatest resistance of teeth to decay.

The levels of fluoride in saliva are very low (about 0.02 part per million fluoride in saliva) even in people who drink fluoridated drinking water. People who do not drink fluoridated water have only about half that amount of fluoride in their saliva thus making their teeth much less resistant to acid attack and therefore to tooth decay.

Fluoride, particularly in drinking water, is largely responsible for the enormous reduction in tooth decay in recent years. The dramatic fall in levels of tooth decay has led to a great improvement in dental health for everyone who consumes fluoridated drinking water.

What have been the effects of water fluoridation on oral health?
The introduction of water fluoridation in Ireland nearly 40 years ago is largely responsible for the 70% falls in levels of tooth decay. Dental health surveys carried out by the state in 1963, 1984, 1989 and 1990 confirm that water fluoridation has had a major impact on the oral health of Irish children and adults.

Dental decay has also declined in areas and countries where there is no water fluoridation, the main reason being the widespread availability of fluoridated toothpastes. However, in areas where the level of risk is high with high frequency consumption of sweets and confectionery, the use of fluoridated toothpastes alone is insufficient to prevent dental decay.

A recent survey of adolescent snacking patterns in 19 European countries revealed that Irish and Scottish children were worst. In 1992, a study comparing the decay levels of 12 years old children in Dublin and Glasgow showed the level of decay was 45% lower in Dublin which is fluoridated compared to Glasgow which is non fluoridated. This is a good indication of the additional benefit provided by water fluoridation when other risk factors are similar.

A recent publication comparing the decay levels for 5 - 7 years old children in 23 countries in Europe shows that Ireland has the lowest level of decay for this age group.

Do we still need water fluoridation?
The level of risk in the Irish population for dental decay is still very high. Along with Scotland, Ireland is the worst of 17 European countries for the amount of sweets and confectionery being consumed by children and adolescents.

Water fluoridation is the most effective population strategy to counter this threat as it reaches the whole population, benefits all age groups and does not rely on compliance.