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Solutions | Fluoride Reduction

2017.12.22

Fluoridation – the act of consciously adding fluoride to water supplies – is now a factor throughout many developed countries to some degree. Already a major feature in North America, Australia, Canada, parts of South America and much of Europe, fluoridation is seen as a major tool in the global fight against dental caries and decay.  Fluoride acts to slow the demineralization of tooth enamel, thereby making the outer surface of the tooth more robust, even under acid attack.  

However there have been significant criticisms of the global fluoridisation program, and fluoride – noted as the most reactive of all the 92 naturally-occurring elements – has been associated with several ill-health instances.  In 1992, over-fluoridation of the water supply in parts of Alaska led to over 250 people being hospitalised, and at least one person dying.  There is also a case for the ethical concerns of fluoridation being applied without consultation.  Whether based in health concerns or moral issues, some homes and businesses choose to filter out the fluorine in the supply, and that can be done with relative ease.

While most commercial fluoride filter producers claim that standard filtration can remove fluoride but in reality, a significant level of filtration is required to remove all traces.  Similarly, neither boiling nor freezing of water are effective means; boiling actually increases the concentration and freezing does nothing to diminish it.  To completely remove fluoride from water in meaningful amounts, a commercial-grade removal system needs to be employed.  Generally, this means using one of two methods;

Activated Alumina Defluorination Filtration.  Activated alumina (Al2O3) is manufactured from aluminium hydroxide using the dehydroxylation process which creates as highly porous material, giving it a very high surface-area-to-weight ratio, due to the many pores running through it.  This makes it an effective fluoride removal filter. Particle size can vary from below a millimetre to several millimetres in diameter, depending upon a number of factors such as water flow and degree of fluoridation.  Generally, filters have to be changed on a regular basis as they become saturated with contaminants, but this again is driven by use and water quality. Activated Alumina is not only an effective means of removing fluoride but also to remove other harmful contaminates such as Thallium and Arsenic which can leech into the drinking water.

The distillation process is far more able at removing fluorine from water, but comes with the twin caveats of time and energy consumption.  Based on a simple process where the water is boiled and then condensed to remove the impurities, requiring the water to be heated on a continuous basis, which is expensive for a long-term process. On an industrial scale, the routine distillation of water using a medium-sized filtration unit can yield around 3 -8 gallons per hour, with larger units producing a greater throughput.  While the distillation process is effective at removing almost anything except for volatile compounds from water, it doesn’t necessarily make it suitable for drinking.  

Distillation tends to leave water with an ‘empty’ taste which can be unpleasant.  This is because, while the fluorine is removed, so are other essential elements such as calcium, magnesium, and iron, and this makes the water seem lifeless.  If the water is being used for anything other than drinking then distillation is an effective process that, despite the energy needed to run it, remains one of the best ways to remove fluoride from an inbound supply.

Fluoride removal via water filters is now routinely carried out in both industrial and domestic settings, making water once again safe to consume.

Tooth care is now a much bigger deal than even a decade ago, and many of the arguments used to promote fluoridation are no longer relevant.  However, the fluoridation program continues and not everyone is comfortable with it.  If that is the case with you, or you are running an industrial system that requires the removal of fluoride, either of the two processes are effective at doing just that.