Available online at Scholars Research Library. Archives of Applied Science Research, 2011, 3 (1):

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1 Available online at Scholars Research Library Archives of Applied Science Research, 2011, 3 (1): ( ISSN X CODEN (USA) AASRC9 Fluoride ion in drinking water and prevalence of dental fluorosis among the population in some tea garden belt villages in Golaghat district of Assam, India *Bhupen Kumar Baruah 1, Ansarul Haque 2, Bhanita Das 3, Kaushik Misra 2, Chitrani Medhi 1 and Abani Kumar Misra 1 1 Department of Chemistry, Gauhati University, Guwahati , Assam, India. 2 Department of Zoology, Gauhati University, Guwahati , Assam, India. 3 Department of Statistics, Gauhati University, Guwahati , Assam, India. ABSTRACT A study was carried out to find out the relationship between prevalence of dental fluorosis among the population as well as concentration of fluoride ion in drinking water in four tea garden belts viz. Latakoojan, Behora, Banwanipur and Negheriting Tea Estate belt of Golaghat district of Assam, India. A total of 20 underground drinking water samples were analysed from March to October, 2009 for fluoride ion estimation. Dental health status for a total of 300 populations was examined. The fluoride concentration was found higher than the permissible limit in 41.67% water samples and prevalence of dental fluorosis in the variation from severe to questionable was 0.48% to 78.36%. The ph range in ring well and tube well water were found to be and respectively. In addition, electrical conductance (EC) of ring well and tube well water samples were found in the range Scm -1 and Scm -1 respectively. Fluoride concentration range was recorded and mg/l in ring well and tube well water samples respectively. This study also indicated prevalence rate of dental fluorosis was 25.67% in female and 74.33% in male belonging to the study area. The studies further revealed that knee pain, back pain and joints pain were common especially in male population. Different eating habits, pattern of tooth brass, lack of awareness and prolong use of small content of fluoride containing water might be the probable factors in higher occurrence of dental fluorosis in this region. This occurrence was observed higher in the people who took equal or more than four cup of tea daily. Key words: Fluoride, Drinking water, Prevalence of dental fluorosis, Tea garden belt. INTRODUCTION Over-exploitation of natural water resources to meet the growing demand has led to rigorous crisis in terms of depletion in water availability as well as its quality. Natural processes also release harmful chemicals to the soil-water environment, decreasing quality. Therefore chemical composition of water is the major criteria for determination of its suitability for domestic use. 175

2 Presence of fluoride in drinking water is necessary for protection against dental caries, however higher level of fluoride ion in drinking water has considerable impact on human physiology [1], [2]. Northeast India lies within the geographical fluoride belt and fluoride occurs as minor constituent of ground water in all categories of hydro-geological settings [3]. The problem of high fluoride concentration in drinking water resource has become an important health related geo-environmental issue in some areas in Assam. Intensified water quality research and health survey conducted during last ten years detects new fluoride affected areas like Nagaon, Majuli, Golaghat etc. in Assam, have already been reported. Therefore a study was carried out to find out the relationship between prevalence of dental fluorosis among the population, along with assessing the concentration of fluoride ion in drinking water sources in four tea garden belts villages viz. Latakoojan TE Belt, Behora TE Belt, Banwanipur TE Belt and Negheriting TE Belt of Golaghat district of Assam, India. A total of 20 underground drinking water samples from four tea garden areas were analyzed from March to October, 2009 for ph, Electrical Conductance (EC), Total Hardness (TH), Total Alkalinity (TA), Total Dissolved Solids (TDS), Ca 2+, Mg 2+, Na +, K + and F -. The ph value of groundwater varies from 7.0 to 8.9 indicating slightly alkaline nature. Except one sample all samples were with in prescribed limit of WHO. It was found that 9 samples (41.67 percent), fluoride was beyond permissible limit. Survey results revealed that majority of the populations had a habit of mixed diet, more than four times tea consumed in a day and unknown about endemic fluorosis. No toothbrush person was recorded percent in the survey percent populations take more than four cup tea daily. Out of 300 samples 74 persons (Male-74.32; Female ) were found questionable to severe fluorosis. It is evident that the populations of the study area continually exposed to higher levels of fluoride from drinking water as the inhabitants rely on this source for potable purpose. MATERIALS AND METHODS Study area: Golaghat district which is famous for Kaziranga National Park and Assam variety of tea Camellia sinensis var Assamica, situated in upper Brahmaputra Valley of Assam, is cartographically confined with latitudes of / N and / N and longitudes of / E and / E with a total geographical area of 3502 sq. km. Climatically it falls in the Eastern Himalayan Zone and enjoys monsoon type of climate. High rainfall, medium to higher temperature, high relative humidity and acidic to neutral type of soil (more than 75 percent) of Golaghat district offers much needed congenial condition for tea plantation [4]. Four selected TE belts in the study are Latakoojan TE Belt, Behora TE Belt, Banwanipur TE Belt and Negheriting TE Belt. Field survey: The work was completed in two phases. The first phase included field survey and the second phase was fluoride estimation in drinking water. For conducting the survey a stratified cluster sampling method was used to select the TE villages. A standard assessment form which encompasses individual questionnaire for collecting general information was used in the field survey. This include oral hygiene habits viz. brushing pattern (using toothbrush or without toothbrush), frequency of brushing (once daily or more), type of toothpaste (commercial paste or indigenous materials), source of drinking water (tube well or ring well), amount of water consumed per day (0-1 liter, 1-4 liter or more than 4 liter), diet (vegetarian, non-vegetarian or mixed), daily tea intake (0-2 times, 2-4 times or more than 4 times) and awareness about fluorosis. Sterile No-4 mouth mirror and No-23 explorers were used for clinical examinations with the help of a doctor. Collection, preservation and analysis of the water samples: Water samples were collected from the household underground sources (Ring Well and Tube Well) in pre-cleaned containers of one-liter capacity between 0900 to 1100 GMT of the day. Collection, preservation, quality 176

3 parameter estimation and calibration of equipments were done using standard methods and techniques [5], [6]. ph of water sample was determined with a digital ph meter (Eutech-356C, India). EC in water were also analyzed by conductometric titrations (ATC-975-C, India). Calcium and Magnesium were estimated by EDTA titration method and sodium, potassium ions by flame photometry (Labtronics, LT-34, India). TA by acid base titration and TDS by evaporation method. Fluorides were estimated by SPADNS method using UV-spectrophotometer (Hitachi-3210) operating the instrument at 570 nm. Statistical analysis was carried out using Statistical Package for Social Sciences (SPSS)-13. RESULTS AND DISCUSSION Water sample characteristics: Among the 20 samples (10 from Ring Well and 10 from Tube Well) 12 samples were collected from household places and 8 from public places. Estimated values of water quality parameters were given in the Table 1 and Table 2. The ph values of groundwater varied from 7.0 to 8.9 indicating slightly alkaline nature. Except one sample all samples are with in prescribed limit of WHO is 6.5 to 8.5. There is no much distinct variation of ph in the sampling source in the present study, indicating that the groundwater is tapping from aquifers of a single formation. The slight alkaline nature of groundwater may be due to the presence of aquifer sediments mixed with clay and mud, which are unable to flush off the salts during rainy seasons. It was found that 9 samples (41.67 percent), fluoride was beyond permissible limit. Table 1: Major cations, anions and fluoride concentrations in Tube Well water samples ph EC TH TA TDS F - Ca 2+ Mg 2+ Na + K All the parameters were expressed in mgl -1 except ph and EC (Scm -1 ) Table 2: Major cations, anions and fluoride concentrations in Ring Well water samples ph EC TH TA TDS F - Ca 2+ Mg 2+ Na + K All the parameters were expressed in mgl -1 except ph and EC (Scm -1 ) Survey sample characteristics: The study sample comprised of 300 inhabitants (Male-177 and Female-123) in the age group of 8-85 years. Oral hygiene habit were analysed and the results 177

4 were presented in Table 3. Majority of the populations had a habit of mixed diet, more than four times tea consumed in a day and unknown about fluorosis. No toothbrush person were recorded percent and they uses indigenous materials like charcoal, neem stick, jatrofa stick etc as toothpaste. During the survey back pain, joint pain and knee pain were found a majority of the people of age more than 40 years. Table 3: Characteristics of Survey Samples Variables Value (%) Male/Female Male- 59; Female-41 Brushing pattern Toothbrush-57.33; No toothbrush Frequency of brushing No- 9.33; Once daily-89; More-1.66 Type of toothpaste Commercial-51.34; Indigenous material Source of drinking water Tube well ; Ring well-20.67; Others-8 Water consumed/day < 0-1 lit. Nil; 1-4 lit ; > 4 lit Diet Vegetarian-1.67; non-vegetarian- Nil; mixed Tea consumed/day < 2 times- nil; 2-4 times-46.66; > 4 times Awareness about fluorosis Known ; Unknown Prevalence of dental fluorosis: The prevalence of dental fluorosis was calculated by taking all the cases of dental fluorosis as the numerator and total sample size as the denominator (Table 4). Severity of dental fluorosis was based on the Deans Fluorosis Index [7] presented in Table 5 and Figure 1. Out of 74 persons 40 were questionable, 18 were very mild and 8 persons found mild, 5 persons moderate and 3 were in severe state. Table 4: Prevalence of Dental Fluorosis Valid Frequency Percent Valid % Cumulative % Absent Present 74 (M-55; F-19) (M-74.32; F ) Total Table 5: Deans Fluorosis Index Valid Frequency Percent Valid % Cumulative % Normal Questionable Very mild Mild Moderate Severe Total Figure 1: Histogram of Prevalence of Deans Fluorosis Index (DFI) 178

5 The presence of fluoride contents in the underground water samples can be attributed as geological deposit, geochemistry of location and extensive application of fertilizers like rock phosphates [8], [9], [10]. Extensive application of phosphate fertilizers in tea gardens and phosphate rocks and minerals present in soil undergoes dissolutions due to heavy rainfall in the monsoon seasons, increases fluoride ion in soil and water sources gradually. Prolong use of fluoride containing water; low calcium food habit and sanitation may be the reason for dental fluorosis in this study area. The study also revealed that habitants having consumption of tea more than four cup per day has found higher prevalence of dental fluorosis [11]. Calcium intake is directly associated with low risk of dental fluorosis and vitamin C also safeguards against the risk [12]. Therefore habitants of such area should advised to take calcium and vitamin C rich food habit as they help in minimum incorporation of fluoride. CONCLUSION A comprehensive analytical and field survey result of prevalence of dental fluorosis and fluoride ion in drinking water sources in tea garden belt villages of Golaghat district, Assam, India has been presented. Although fluoride contents beyond the guideline values of WHO have been found in a few number of samples, prevalence of dental fluorosis found in alarming state. The number of users of deep tube well is relatively larger and they are economically not well-off. Keeping in the view of harmful effect of fluoride ion in drinking water emphasis may be given to adopt some defluoridation technique in the study area. REFERENCES [1] W. H. Bowen, J. Am. Dental Assoc., 2002, 133, [2] W. J. Butler, V. Segreto, E. Collins, Am. J. Public Health, 1985, 75, [3] A. K. Singh, S. Bhagowati, T. K. Das, D.Yubbe, B.Rahman, M. Nath, P. Obing, W. S. K. Singh, C. Z. Renthlei, L. Pachuau, R. Thakur, ENVIS Bulletin: Himalayan Ecology, 2008, 16(1),6-11. [4] P. K. Barua, P. K. Bora, J. North Easter Council, 1975, 2, [5] S. C. Lenore, E.G. Arnold and D.E. Andrew (Ed), Standard methods for the examination of water and wastewater, 20th Edition, (APHA, AWWA and WEF, 1998). [6] R. K. Trivedy, P. K. Goel; Chemical and Biological Methods for Water Pollution Studies, Environmental Publication, Karad, India, 1986, 1, [7] T. H. Dean, E. Elvolve, Public Health Rep., 1935, 50, [8] K. R. Bulusu, W. G.. Nawlakhe, Indian J. Environ Health, 1990, 32, [9] B. Rao, Nagamallesword, S. V. R. Rao, G.. V.V. S. Chowdary, Ind. J. Env. Protection, 1990, 10(5), [10] K. Karthikeyan, K. Nanthakumar, P. Velmurugan, S, Tamilarasi, P. Lakshmanaperumalsamy, Environ Monit Assess., 2010, 160, [11] M. P. Whyte, K. Essmeyer, F. H. Gannon, W. R. Reinus, Am. J Med., 2005, 118, [12] C. Dinesh, Indian J. Environ Protection, 1998, 19(2),