Glass half empty?
The USA Centers for Disease Control and Prevention recently released the latest water fluoridation statistics for 2008, which showed that 58 per cent of people living in California receive fluoridated water, more than double the 27 per cent who benefited in 2002.1
Thanks to efforts led by a charitable trust established by the California Dental Association (CDA) Foundation, it has steadily expanded access to water fluoridation. California now has the largest total number of residents of any American state receiving fluoridated water; 21.5 million people or four times the Scottish population.
Before the CDA Foundation- led efforts to expand fluoridation in the late 1990s, only 17 per cent of California’s population received the benefit of fluoridated water. Progress was achieved largely by legislation approved in 1995.
The CDA fulfils the same role in the state of California as the British Dental Association does in Scotland, including being an advocate for water fluoridation.
Since then, the CDA Foundation and its partners, often working with private funders, have provided grants to help communities initiate fluoridation projects.
The USA federal government’s Healthy People 2010 objective for fluoridation is 75 per cent, which is a target that the CDA foundation reports it plans to achieve in the near future.
Across the USA, 72 per cent of the population on mains water receives water fluoridation; the state of Maryland has 99.8 per cent benefiting from water fluoridation.
Across the Pacific in 2008, the state of Queensland in Australia also adopted legislation to promote water fluoridation with the aim of 90 per cent of Queensland residents having access to fluoridated water by 2012. Under this legislation, a statutory duty was placed on public water suppliers who supply water to more than 1,000 people, to add fluoride to the public water supply under their control or management.
The Queensland legislature also committed AUS$35 million to improve the infrastructure of water treatment plants over this six-year period and implement fluoridation. The new water bill followed a petition from the Australian Dental Association of Queensland signed by more than 25,000 Queenslanders supporting water fluoridation.2
In 2008, 65 per cent or 11.5 million Australians benefited from drinking fluoridated water and this proportion is increasing. Like the USA and the UK, fluoridation of water supplies has been practised for more than 50 years without credible evidence of any harmful effects on general health. For generations, millions of people have lived in areas where fluoride is found naturally in the drinking water in concentrations as high as or higher than those recommended to prevent tooth decay. Research conducted among these groups confirms the safety of fluoride in the water supply. While we welcome more research, there are no concerns about the safety and effectiveness of water fluoridation.
In Canada, 45 per cent of the population receive fluoridated water, in Eire 67 per cent or two million people, in Spain about 10 million, in Singapore and Hong Kong the proportion is 100 per cent. In New York, with a population of eight million, the water was fluoridated 45 years ago in 1965. Virtually all of the major cities in the United States of America are fluoridated.
In the UK, water fluoridation, either natural or adjusted, is available to only about 10 per cent of the English population. The only area in Scotland which did have naturally fluoridated water at 1ppm was on the Moray coast.3 However, the water came from a borehole supply which is no longer used. Most of the water collected for domestic use in Scotland has a moorland catchment, which means it will be low in fluoride. So, in Scotland, despite having a public water supplier, there is essentially no water fluoridation, either natural or artificial.
Across Europe only England, Ireland and Spain practise artificial water fluoridation and while many other European countries do have natural water fluoridation, they prefer to rely on professionally applied fluorides for the preventive benefits; those countries within the European Union are governed by water quality directives which allows for natural fluoride levels of up to 1.5ppm. (Council Directive 98/83/EC. 3 November 1998. The quality of water intended for human consumption). The target level for artificial water fluoridation in temperate climates is lower at 1mg/L and unlike school-based programmes, it should be noted that people of all ages do benefit from water fluoridation.
Dental fluorosis is present in areas both with and without water fluoridation and in a European context the mild dental fluorosis found is a minor cosmetic issue.
The suggestion that water fluoridation is mass medication is false. All water supplies, even in Scotland, have some natural fluoride and the water fluoridation process just involves adding fluoride (or removing fluoride in some areas of the world) to the level that protects dental health. It does not involve adding anything to the water that is not already present. There is no difference between fluoride present naturally and that which is added to water.
Water fluoridation both reduces tooth decay and also the need for dental treatment. In Scotland extraction of teeth is still the main reason that young children are admitted to hospital for treatment under a general anaesthetic. Dental treatment creates additional problems for some (e.g. diabetics, haemophiliacs, transplant patients, the immune compromised) for whom a healthy mouth is essential.
Some evidence shows that fluoridation is particularly beneficial in preventing tooth decay in deprived groups of children who may have difficulty with their own preventive care. However, it benefits all children, and reduces dental health inequalities.
A recent paper reporting on natural fluoridation and the effect on the dental health of children across Denmark concluded that: “The study confirmed previous findings of an inverse relation between fluoride concentration in the drinking water and dental caries in children. This correlation was found in spite of the extensive use of fluoridated toothpaste and caries-preventive programs implemented by the municipal dental services in Denmark.”
They reported that at a level of fluoride of about 1ppm, a reduction in tooth decay of around 50 per cent was found.4
So even in countries with widespread use of fluoridated toothpaste and caries-preventive programmes, such as in Scotland, the evidence shows that water fluoridation would provide major, additional improvements in child dental health.
The recent lesson from California and Queensland, and historically elsewhere, is that local dentists need to engage politicians in promoting a statutory duty on public water suppliers to fluoridate.
Colwyn Jones is a Consultant in Dental Public Health for NHS Health Scotland
1: http://www.cdc.gov/ fluoridation/statistics/ 2008stats.htm
2: http://statements.cabinet. qld.gov.au/MMS/ StatementDisplay Single.aspx?id=56475
3: Stephen KW, Macpherson LMD, Gilmore WH, Stuart RAM, Merrett MCW. A blind caries and fluorosis prevalence study of schoolchildren in naturally fluoridated and nonfluoridated townships of Morayshire, Scotland. Community Dent Oral Epidemiology 2002; 30: 70-9.
4: Kirkeskov et al 2010. The association between fluoride in drinking water and dental caries in Danish children. Linking data from health registers, environmental registers and administrative registers. Community Dent Oral Epidemiol 2010; 38: 206-212.
The views expressed in this article are solely those of the author.