MANGALURU: The southern parts of the state have lower levels of fluoride in ground water and north-eastern parts have markedly high levels. It is particularly high in Kolar and Koppal districts, reveals an evidence-based study published in a UK-based peer-reviewed journal titled ‘Perspective in Public health’ (Vol XX, No XI).
As drinking water is the main source of fluoride intake for humans, Prof Chitta R Chowdhury, head of the Department of Oral Biology and Genomic Studies, A B Shetty Memorial Institute of Dental Sciences (ABSMIDS), Nitte University, and seven other researchers decided to estimate concentrations of fluoride in drinking water across the state.
“By eventually developing an updated fluoride concentration intensity map, interventions can be planned to promote good oral and general health,” Prof Chowdhury stressed in an e-mail interview to Express.
New Delhi-based Chemtron Analytical Instrument Pvt Ltd was engaged to collect samples from five equidistant sites in each of the 29 districts, categorised into four zones. The samples collected were analysed in their department, Prof Chowdhury said.
The results revealed that concentration of fluoride in drinking water ranged between 0.07 ppm (lowest) and 5.70 ppm (highest). The mean fluoride level was found to be highest in north-eastern zone (1.61 ppm – Bidar, Gulburga, Yadgir, Raichur, Koppal and Ballari). Koppal (5.70 ppm) and Kolar districts (3.06 ppm) had elevated fluoride concentrations.
WHO recommends that drinking water should contain fluoride concentration between 0.8 ppm and 1.5 ppm.
No Response from Health Minister
The mean fluoride concentration of drinking water in south-western zone was lowest at 0.41 ppm (Haveri, Davangere, Shivamogga, Udupi, Dakshina Kannada, Chikkamagaluru, Hassan and Kodagu).
“While visiting some areas like Tumakuru and Pavagada, which have flouride concetration above 2 ppm, we found that 98 per cent of students in the age group of 12 to 15 years had dental fluorosis,” he informed.
The study also revealed that water with high fluoride concentration during summer season was unsuitable for human consumption.
Prof Chowdhury and team had offered a solution on setting up de-fluoridation plant to ensure that drinking water sources in the state had safe fluoride level (0.8-1.5 ppm), (more than 50 per cent de-fluoridation plants were not working) and fluoridating Mangaluru City Corporation’s central water supply to prevent dental caries (dental decay).
“But there has been no response from Chief Minister’s office, Health Minister U T Khader or MCC Mayor,” Prof Choudhry lamented.
How Does Fluoride Affect Us?
Studies have shown that ‘dental caries’ (tooth decay or breakdown of teeth) in children is more when fluoride in drinking water is less than 0.5 ppm. Fluoride deficiency is also known to cause Osteoporosis. An overdose of fluoride leads to dental fluorosis.