Population Health - Public and Environmental Health
File No.: H01721-04
Fluoridation Committee Annual Report 2011-2012
2.The Fluoridation Committee 4
3.Achievements in 2011-2012 5
4.Fluoridation Plant Status and Performance 6
4.1.Fluoridation Plant Status 6
4.2.Fluoridation Plant Performance 6
4.3.Plant Reliability 9
5.Future Activities 11
Figures and Tables
This report was prepared in accordance with section 17(2) of the Fluoridation Act 1968 (the Act).
Water fluoridation is the adjustment of fluoride in drinking water to a concentration that helps prevent dental decay. The National Health and Medical Research Council (NHMRC) affirms that water fluoridation remains the most socially equitable method of achieving community-wide exposure to the health benefits of fluoride. Adjusting fluoride levels to the NHMRC-recommended levels in public water supplies has proven a safe and effective measure in the prevention of dental health problems.
Water fluoridation receives endorsement by more than 150 science and health organisations worldwide and fluoridation programs have the strong support of the NHMRC, the World Dental Federation, the International Association for Dental Research and the World Health Organisation
The National Oral Health Plan 2004-2013 suggested that for each dollar invested in water fluoridation the savings in dental treatment costs range from $12 to $801. Comparable financial data are not available for Tasmania however in Victoria in the past 25 years, fluoridation is estimated to have saved the Community nearly $1 billion in avoided dental costs, lost productivity and saved leisure time2. Given the improvements in oral health and reductions in associated health costs, State and Territory governments intend to extend their fluoridation programs under the National Oral Health Plan 2004-2013.
In Tasmania, 88% of the population receives fluoridated drinking water. In accordance with the National Oral Health Plan 2004-2013, public water supply systems servicing all communities above 1000 in population in Tasmania are fluoridated. The exceptions are Scamander (population of 1250), Fingal (1590) and Bicheno (1400).
Fluoridation of Tasmanian public drinking water supply systems commenced in 1953 (in Beaconsfield), making Tasmania the earliest jurisdiction to do so. Under the Fluoridation Act 1968, the Minister for Health directs the water corporations (based on recommendations from the Fluoridation Committee) to fluoridate specific public water supplies in a prescribed manner. Included in this Ministerial Direction is the need to monitor the level of fluoride in drinking water on a daily basis.
The Fluoridation Committee’s Annual Report 2011-12 is the third reporting period in which the water corporations are the owners and service providers of fluoridation assets and water fluoridation respectively. The role of the Department of Health and Human Services (DHHS) remains as the regulatory body with strategic oversight being provided by the Fluoridation Committee.
The Fluoridation Committee consists of five members, each appointed by the Minister for Health. The Deputy Director of Public Health (as a delegate of the Director of Public Health) occupied the position of committee chair until May 2012. After the Deputy Director of Public Health left the Department, the role of chairperson was assumed by the State Manager of Environmental Health Services. The principal functions of the Fluoridation Committee are to act as an expert advisory committee to interested parties including the Minister, on matters relating to fluoridation of drinking water and to provide strategic oversight of fluoridation works in Tasmania and report on the performance and outcomes of the fluoridation plants throughout the state.
For 2011-12 the Fluoridation Committee members were:
Dr Chrissie Pickin, Deputy Director of Public Health, Department of Health and Human Services (resigned May 2012).
Improved level of fluoride added to the water from the Box Hill (National Park) Fluoridation Station which contributes to the greater Hobart are water supply. (Further improvement has occurred since the reporting period.)
Fluoridation Plant Status and Performance
Fluoridation Plant Status
There were 39 operating fluoridation plants in Tasmania for the reporting period of 2011-12. These plants are designed to provide fluoridated drinking water to approximately 87 per cent of the Tasmanian population. This is a significant proportion as public drinking water supplies provide reticulated water to approximately 89 per cent of the population.
This is the same number of operational fluoridation plants as reported during the 2010-11 reporting period.
Twenty-one plants use sodium fluoride (NaF), which is a white material available as an odourless powder or in a crystalline form. Fluoridation is accomplished by dissolving the sodium fluoride in water. To minimise occupational health and safety issues, the Fluoridation Committee has approved the use of soluble bags made of Poly Vinyl Alcohol (PVA) for the addition of sodium fluoride to drinking water.
Eighteen plants use Fluorosilicic acid (H2SiF6), commonly known as FSA. FSA has advantages with regard to dosing accuracy and economics and is in use in most of the large water treatment plants around the State. The use of automated dosing systems to add FSA to water significantly reduces occupational health and safety issues. FSA is an extremely corrosive and volatile liquid with a pH level of 1.2 that can lower the pH of drinking water if the water does not have sufficient buffering capacity to neutralise the effect of this acidic fluoridating agent.
Fluoridation Plant Performance
Under the Fluoridation (Interim) Regulations 2009, the Regional Water Corporations must maintain and operate fluoridation plants to ensure compliance with the following performance specifications:
the fluoridation concentration range required in the drinking water supply is 0.8 to 1.2 mg/L of fluoride
the maximum level of fluoride allowed in the water is 1.5 mg/L. (This latter maximum level is based on the Australian Drinking Water Guideline health limit)
Additionally under the Tasmanian Code of Practice for the Fluoridation of Public Water Supplies 2007-2010, the Regional Water Corporations must maintain and operate fluoridation plants to ensure compliance with the following performance specifications:
meet a target over a calendar year, that greater than 90% of all routine fluoride samples (both treated and distributed) fall within the fluoride concentration operating range of 0.8 mg/L to 1.2 mg/L.
All three Regional Water Corporations submitted monthly performance reports during 2011-12.
There are two metrics for measuring compliance of a fluoridation plant based on the reported fluoride concentrations. Firstly all daily fluoride concentrations are averaged over the reporting period with the resultant average fluoride concentration being assessed as compliant if it falls within the operating target range of 0.8-1.2 mg/L. Table 1 shows that 33 of the 39 fluoridation plants that operated throughout 2011-12 maintained an average fluoride dose within the required fluoride concentration range of 0.8 mg/L to 1.2 mg/L. This compares with 36 of 39 compliant fluoridation plants in 2010-11 and 35 of 39 in 2009-10. The non-compliant fluoridation plants failed to add sufficient fluoride to achieve the optimum fluoride range in the water supply.
The drop in compliance noted in this reporting period is largely attributable to the Regional Water Corporations actively addressing the operational management of their fluoridation plants. Corrective action often involves a shutdown (or partial shutdown) of a fluoridation station for a period of time that then skews the statistical analysis of the figures.
The following non-compliant plants were noted during the 2011-12 reporting period with their average fluoride concentration given:
The second measure of compliance assesses the percentage of individual reported fluoride concentrations (on a daily basis) that fall within the operating target range of 0.8-1.2 mg/L. The Code of Practice sets 90% as the compliance standard for this assessment. Graphically the compliance of each of the Regional Water Corporations can be seen in Figure for Southern Water, Figure for Cradle Mountain Water and Figure for Ben Lomond Water.
It should be noted that the two different measures of compliance cannot be directly compared as it is possible to exhibit compliance with one measure and not the other. For example the Fern Tree fluoridation plant operated by Southern Water reported an average yearly fluoride concentration of 0.85mg/L and was thus assessed as being compliant. However, the reported concentrations were only within the target operating range for 57% of the reported figures.
Figure : Compliance3 of Southern Water Fluoridation plants against the target operating range (0.8-1.2 mg/L) for 2011-12
Figure : Compliance4 of Cradle Mountain Water Fluoridation plants against the target operating range (0.8-1.2 mg/L) for 2011-12
Figure : Compliance5 of Ben Lomond Water Fluoridation plants against the target operating range (0.8-1.2 mg/L) for 2011-12
Fluoridation plant reliability focuses on the level of failure/breakdown of the fluoridation plants. Historically the Fluoridation Committee has recommended a reliability level of 95%. This means that the fluoridation system is operational for 95% of the time. The most common causes for low reliability are ageing equipment and/or a major malfunction, which can result in the system being offline for a significant period of time. Fluoridation plants which were not operational for a period of time for the purpose of upgrades and to address non-dosing issues (e.g. OH&S requirements) are not included in this measure.
The plant reliability metric was utilised up to April 2012. The Fluoridation Committee decided that this measure was no longer adding any new valuable information with respect to the reliability of the fluoridation plants. The metric was initially developed to examine the plant operation in the earlier days of management when noted problems with dosing equipment were being experienced.
Error: Reference source not foundshows that during 2011-12, 29 of the 39 fluoridation plants had acceptable reliability, which is a decrease from the previous reporting period when 34 of the 39 fluoridation plants achieved 95% or higher reliability. During 2009-10, 35 of the 39 fluoridation plants achieved 95% or higher reliability. It appears that the main factor affecting the drop in plant reliability compliance is associated with the increased instances of Regional Water Corporations notifying of disruptions to fluoridation plants. It is also reflective of the corrective actions undertaken by the Regional Water Corporations to reinstate fluoridation dosing after identifying problems.
The following non-compliant plants were noted during the 2011-126 reporting period with their plant reliability given: