Low Cost Household Defluoridation to Remove Excess Fluoride in Groundwater
Third South Asia Geological Congress Lahore, Pakistan.

In recent surveys conducted in Sri Lanka, it has been found that nearly 20 percent of the wells in dry zone areas have more than 2.0 mg/l fluoride in groundwater. In addition, in nearly 30 percent of the wells the fluoride content is 2.0-1.0 mg/l. This has led to mottling of teeth and unsightly brown discoloration of the teeth in the school children of age group 8-20 years. This has reached endemic proportions in dry zone areas in Sri Lanka.

Several methods are available to defluoridate  the water but the filter medium used has to be supplied from time to time. The defluoridation method developed, has unique feature of having the filter-medium in the very locality. The filter-medium used is freshly burnt broken pieces of bricks in PVC filter of 1 meter in height. The operation and maintenance of this filter unit has been found to be well within the capability of rural communities. The results clearly showed that this low cost method could be easily carried out in order to get defluoridated water. The efficiency level of these defluoridators changes from 85 percent removal at the start, and tapers down to 25 percent removal at the end of the cycle. This low cost method could be adopted in other developing countries successfully to reduce fluoride-rich water to acceptable standards. This is an appropriate and affordable technology for the rural communities in the developing countries.    

Author(s):
J.P. Padmasiri
National Water Supply & Drainage Board, Sri lanka.