ABSTRACT
Fluoride occurs naturally in our environment but we consume it in small amounts. Exposure can occur through dietary intake, respiration and fluoride supplements. The most important factor for fluoride presence in alimentation is fluoridated water. Fluoride content in groundwater has become a national issue affecting the entire India. When the recommended limit of fluoride by WHO is 1.5 mg/L, in some particular parts of India fluoride levels are as high as 35 mg/l. Increased fluoride intake causes dental fluorosis, skeletal fluorosis and neurological problems. Major problems associated with fluoride remediation are lack of cheap adsorbent to remove fluoride content in water for poor communities of India. Hence, development of community-based defluoridation unit is needed with a technique which is cost-effective, technologically simple in operation while being able to keep the fluoride level in permissible limits. On the basis of extensive investigations, different researchers have developed simple and economical domestic defluoridation processes The present review gives a brief account of prevalence, sources of fluoride toxicity and cost effective defluoridation method carried out on effects of fluoride in the last few decades. Thus cost effective absorbent which has high efficacy in fluoride removal from water can be provided to poor communities thereby preventing fluorosis
ABSTRACT
Objective To understand the schedule and effectiveness of water-improving defluoridation projects comprehensively of control of fluorosis in drinking-water-borne endemic fluorosis areas in Shandong Province,and to provide a scientific basis for making strategies for prevention and control of the disease.Methods In accordance with the requirements of Shandong Provincial Survey Scheme for Implementation of Prevention and Control Measures of Endemic Fluorosis,the progress of water-improving defluoridation projects was investigated in Shandong Province.The types of water source,scale and operating conditions for water-improving defluoridation projects in 17 cities of the province were investigated.Water fluoride contents of the normal operating projects were detected by F-ion selective electrode.Results ① By the end of 2012,a total of 3 539 water-improving defluoridation projects were built that covered 9 856 fluorosis villages,113 counties,17 cities in the province,and the water-improving rate was 91.01％ (9 856/10 830).The type of water source of water-improving project was mainly groundwater,accounted for 93.78％ (3 319/3 539) of the total projects.As for the scale of the water-improving projects,small centralized water supply projects were the main projects,accounted for 92.96％(3 290/3 539) of the total projects.\)Of all the water-improving defluoridation projects,normal operating projects accounted for 89.12％(3 154/3 539),intermittent and scrapped projects accounted for 3.25％(115/3 539) and 7.63％ (270/3 539),respectively.③Among normal operating projects,the number of projects with water fluoride content ≤ 1.20 mg/L was 1 925,accounted for 72.40％(1 925/2 659).The number of projects with water fluoride content ＞ 1.20 mg/L was 734,accounted for 27.60％ (734/2 659); among them water fluoride contents between 2.01-4.00 mg/L and ＞ 4.00 mg/L were 233 and 65,respectively,and the highest water fluoride value was 9.71 mg/L.Conclusions The progress of water-improving projects in some cities (counties) of Shandong Province is still slow.Some of the water-improving projects can not be operated normally or have been scrapped,and water fluoride content has exceeded the standard seriously.So the prevention and control measures need to be further strengthened,funding should be increased,and the operating conditions and water quality of the water-improving defluoridation projects in Shandong need to be further improved.
ABSTRACT
Background: The published literature on the prevalence and severity of dental caries and dental fluorosis among school going children in Nalgonda district - An Endemic Fluoride belt was lacking . Objectives: To assess the prevalence and severity of dental fluorosis and dental caries among 12 and 15 years old children in relation to fluoride concentration in drinking water . Settings and Design: It was a cross-sectional study, done in Nalgonda district of Andhra Pradesh, India (endemic fluoride belt) . Materials and Methods: 5 of the 59 mandals in the district of Nalgonda were selected by simple random sampling. Then, 3 schools from each of these selected mandals were chosen at random. All the eligible 6 th and 9 th standard children were considered for final analysis. The demographic and other relevant information was collected by 3 trained and calibrated dentists, using a structured questionnaire. Dental caries were recorded using dentition status and treatment needs and fluorosis were recorded by Dean's fluorosis index. The statistical analysis was done using SPSS version 16. Results: The prevalence of dental caries among children was 56.3% with the highest in below optimal fluoride area (71.3%) and lowest in optimal fluoride area (24.3%). The prevalence of dental fluorosis was 71.5%. The prevalence was 39.7% in below optimal fluoride area and 100% in high and very fluoride areas. The prevalence and severity of fluorosis increased with increasing fluoride concentration. The caries experience was more among boys than girls. Conclusion: There was a negative correlation between dental caries and fluoride concentration for the entire study population. However, in high fluoride areas, there was a positive correlation between fluoride concentration and dental caries. Water defluoridation on an urgent basis is a priority here than water fluoridation, because the prevalence and severity of dental flurorosis is very high.
ABSTRACT
Fluoride is an acute toxin and is deemed to be slightly more dangerous than even lead. 48 water samples collected from hand pumps and bore wells belonging to 24 gram panchayats (villages) of Kanduku revenue sub division of Prakasam district in Andhra Pradesh, were chemically analyzed for fluoride ion concentrations. High and low fluoride containing regions were identified on the basis of fluoride levels in the water samples and also on the prevalence rate of dental and skeletal fluorosis of the study area. Further, water samples containing high fluoride levels were tried for defluoridation by employing Active Carbons of abundantly available low-cost plant byproducts. These materials under optimum conditions of adsorbent dosage, time of equilibration and pH, were found to be successfully decreasing the fluoride ion concentration below permissible limits without disturbing drinking water quality standards.
ABSTRACT
A systematic study has been carried out to explore the water quality index of ground water of various locations of Gulbarga city. Ten water samples from tube wells, open wells and hand pumps at various locations were collected using standard procedural methods and analyzed for pH, nitrate, turbidity, total hardness, alkalinity, fluoride, sulphate, sulphide, COD and DO. Biological examinations were extensively carried out on each sample using known standard methods. In this study overall water quality of Gulbarga city is very poor and unsuitable for drinking purposes. Present study recommends that the top priority should be given to water quality monitoring and indigenous technologies should be adopted to make water fit for drinking after treatment such as desalination and defluoridation.
ABSTRACT
Objective To understand the current status of the prevention and control of endemic fluorosis in the southwestern area of Shandong province. Methods In 2007, the progress of water-improving defluoridation, the operating state and water fluoride content of the water-improving project, which was determined by fluorosis selective ion electrode, and the inhabitant related indexes of endemic fluorosis were extensively surveyed in the three main fluorosis counties-Jiaxiang, Yuncbeng and Liangshan of the southwestern area of Shandong province. Results Among 1371 fluorosis villages in the 3 counties, 53.61%(735/1371) of which had undergone water-improving defluoridation, the rate in Jiaxiang, Yuncheng and Liangshan being 38.0% (220/579),65.51% (378/577) and 63.72% ( 137/215 ) respectively; the normally functioning rate of this project was 76.73% (564/735), projects out of order accounted for 23.27% (171/735). Among 263 well-functioning projects from the three counties, the rate with water fluoride higher than 1.0 mg/L was 35.36%(93/263), the maximum value being 4.17 mg/L. The urine fluoride content of 440 children aged 8 - 12 years and 484 adults over 30 years old were examined in 13 fluorosis villages of the three counties, the geometric mean was 2.98,3.06 mg/L respectively; the individual maximum was 12.83,14.49 mg/L respectively; the detectable rate of dental fluorosis among children aged 8 - 12 was 84.28% (649/770) ,17.66%(136/770) had defect and the index of dental fluorosis was 1.89; the rates of the clinical and X-ray skeletal fluorosis of the adults aged more than 30 were 44.40%(234/527) and 24.67%(130/527) respectively, and the abnormal electrocardiography rate was 32.43% (168/518) in the adult, mostly T-wave abnormality. Conclusions The progress of the water-improving defluoridation in the southwestern area of Shandong province was relatively slow, the water fluoride content of the water-improving projects seriously exceeded standard, and the condition of the fluorosis had not been effectively controlled.
ABSTRACT
Objective To investigate the distribution of water-borne fluoride and the current status of water defluoridation project by improving drinking water quality in endemic fluorosis areas in Shandong province,and to provide scientific basis for making strategies in prevention and control of the disease. Methods According to "the National Technical Scheme for Endemic Disease Control in 2004, 2005 and 2006", 113 endemic fluorosis diseased counties(cities, and districts) of the province's 17 cities were screened in order to investigate the fluoride level in drinking water in fluorosis villages, recheck the fluoride level after implementing the water defluoridation project, and investigate the current status of the water defluoridation project. The fluoride level in drinking water was determined by F-ion selective electrode. Results There were a total of 5816 water defluoridation projects in the province. Most of them were carried out by drilling a deep well to get under-ground water. The wells still in good condition were accounted for 72.80% (4234/5816). Intermittent operated wells were accounted for 3.11% (181/5816). Abandoned wells were accounted for 24.09%(1401/5816). Level of water fluoride was determined in 6940samples from fluorosis villages(villages that not carry out the water defluoridation project as well as villages carried out the water defluoridation project with abandoned wells were included) and the value that lower or equal to 1.00mg/L was determined in 2987 villages which accounted for 43.04% (2987/6940). Level of water fluoride that over 1.00 mg/L was found in 3953 villages which accounted for 56.96% (3593/6940), and the highest level of water fluoride was 11.33 mg/L. Level of water fluoride were determined in 4415 samples from water defluoridation project and the value lower or equal to 1.00 mg/L was in 2983 wells which accounted for 65.53%(2983/4415). The value over 1.00 mg/L was in 1522 wells which accounted for 34.47%(1522/4415), the highest value of water fluoride was 9.71 mg/L. Conclusions Level of water fluoride in up to 1/2 of the villages and 1/3 of the projects, is still higher than the standard in Shandong province. Nearly 1/4 of the project has been abandoned. The current situation for endemic fluorosis control is still not good in the province, countermeasures for endemic fluorosis must be carried out as soon as possible and surveillance of water defluoridation project must be strengthened.