Researchers from India have developed a new filter system that uses a medicinal herb to remove fluoride from drinking water quickly and easily. They believe that populations living in areas with high levels of naturally occurring fluoride in ground-water could benefit from the invention especially.
In the study, the researchers used parts of Tridax procumbens, a commonly used medicinal herb from India that has been tested in the extraction of toxic metals from water, to develop a bio-carbon absorbent for fluoride.
Malairajan Singanan, a chemist from the Presidency College in Chennai, explained that by loading plant tissue with aluminium ions a safe carbon filter can be created to absorb fluoride ions from 27°C warm water passing through it. Initial trials demonstrated that 98 per cent of fluoride could be removed in three hours by using as little as 2 g of the bio-carbon filter, he said.
Although fluoride is added to drinking water in most industrialised countries, it is highly debated by experts, as in some countries fluoride levels exceed the level of 1.5 mg/l considered safe by the World Health Organization. Singanan hopes that the new filter will provide an inexpensive way to de-fluoridate water in regions such as India, China, Sri Lanka, Spain, Holland, Italy and Mexico, among others, where natural levels of fluoride in the ground-water are very high.
The study was published in the March issue of the International Journal of Environmental Engineering.
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