Health Impact of Supplying Safe Drinking Water on Patients Having Various Clinical Manifestations of Fluorosis in an Endemic Village of West Bengal

BACKGROUND: Excessive fluoride in drinking water causes dental, skeletal and non-skeletal fluorosis which is encountered in endemic proportions in several parts of the world. The World Health Organization (WHO) guideline value and the permissible limit of fluoride as per the Bureau of Indian Standards (BIS) is 1.5 mg/L. Studies showed that withdrawal of sources identified for fluoride, often leads to reduction of fluoride in the body fluids (re-testing urine and serum after a week or ten days) and results in the disappearance of non-skeletal fluorosis within a short duration of 10-15 days. OBJECTIVE: To determine the prevalence of signs and symptoms of suspected dental, skeletal and non-skeletal fluorosis along with food habits, addictions and use of fluoride-containing toothpaste among participants taking water with fluoride concentration above permissible limit and to assess the changes in clinical manifestations of the above participants after consumption of safe drinking water with fluoride concentration below permissible limit. MATERIALS AND METHODS: A longitudinal intervention study was conducted from October 2010 to December 2011 in a village selected randomly in Purulia District of West Bengal which is endemic for fluorosis. Thirty-six families with 104 family members in the above village having history of taking unsafe water containing high level of fluoride were selected for the study. The occurrence of various dental, skeletal and non-skeletal manifestations of fluorosis along with food habits, addictions and use of fluoride-containing toothpaste among the study population was assessed; the impact of taking safe water with fluoride concentration below permissible limit from a supplied community filter on these clinical manifestations was studied by follow-up examination of the above participants for six months. The data obtained is compared with the collected data from the baseline survey. RESULTS: The prevalence of signs and symptoms of dental, skeletal and non-skeletal fluorosis was (18.26%), (18.26-43.26%) and (12.49-38.46%) among the study population. Withdrawal of source(s) identified for fluoride by providing community filters supplying safe water along with nutritional interventions lead to 1.92% decrease of manifestation of dental fluorosis, 2.88-18.26% decrease of manifestations of skeletal fluorosis and 3.8-5.77% decrease in manifestations of non-skeletal fluorosis within six months. Following repeated motivation of participants during visit there was also 2.88% decrease in the usage of fluoride-containing toothpaste, 4.81% decrease in consumption of black lemon tea, supari and tobacco which are known sources of fluoride ingestion in our body. CONCLUSION: Increased prevalence of dental, skeletal and non-skeletal fluorosis was found among the study population. Withdrawal of sources(s) identified for fluoride by supplying community filter, dietary restriction and other nutritional interventions led to decrease of manifestations of the three types of fluorosis within six months. The government should play a vital role in ensuring drinking water safety at the household and community level by supplying domestic filters at affordable costs and community filter along with nutritional intervention to the fluorosis-affected villages on a priority basis to mitigate the problem.