High Levels Of Fluoride Research Articles

Synthesis of Bio-Adsorbent for Removal of Fluoride from Groundwater – A column study

High fluoride levels in groundwater used for drinking have caused health concerns for millions of people across the world. Pakistan is one of the countries that have been contaminated by these toxins. However, a little amount of fluoride is required for tooth and bone strength. In any event, the presence of too much of it in drinking water can cause diseases in both people and animals. This study is focused on the synthesis of bio-adsorbent bone char to adsorbent for the removal of fluoride from groundwater obtained from Islamkot district Tharparkar. The bone char was synthesized by pyrolysis of used cow bones at a temperature of 550 degrees C. The fluoride removal efficiency of bone char was optimized. The impacts of different operating parameters such as flow rates (5mL/min, 10mL/min, and 15mL/min), bed height of adsorbent (2cm, 4cm, and 6cm), initial fluoride concentration 7.85 mg/L, and contact time (30min, 60min, and 90min) were studied. The removal efficiency was enhanced by increasing the adsorbent bed height and decreasing contact time and flow rate. With an initial concentration of fluoride 7.85mg/L, the maximum removal efficiency of 90.2% was obtained when the adsorbent bed height, flow rate, and contact time were optimized to 6 cm, 5 mL/min, and 30min, respectively. The finding showed that bone char can be used as an eco-friendly, inexpensive, and efficient adsorbent for removing fluoride from groundwater.

Prospects for the Role of Ferroptosis in Fluorosis.

As a strong oxidant, fluorine can induce oxidative stress resulting in cellular damage. Ferroptosis is an iron-dependent type of cell death caused by unrestricted lipid peroxidation (LPO) and subsequent plasma membrane rupture. This article indicated a relationship between fluorosis and ferroptosis. Evidence of the depletion of glutathione (GSH) and increased oxidized GSH can be found in a variety of organisms in high fluorine environments. Studies have shown that high fluoride levels can reduce the antioxidant capacity of antioxidant enzymes, while increasing the contents of reactive oxygen species (ROS) and malondialdehyde (MDA), resulting in oxidative stress and fluoride-induced oxidative stress, which are related to iron metabolism disorders. Excessive fluorine causes insufficient GSH, glutathione peroxidase (GSH-Px) inhibition, and oxidative stress, resulting in ferroptosis, which may play an important role in the occurrence and development of fluorosis.

Fluoride concentrations in drinking water and health risk assessment in the south of Algeria

Drinking water is the primary source of fluoride intake by humans worldwide. Algeria, Africa's largest country, has been reported to have moderate to high fluoride levels in the water, particularly in the Southern and Saharan regions. In the south of Algeria, dental fluorosis is considered an epidemic that is spreading within the population by health professionals.This study aimed to determine fluoride concentrations in drinking water consumed by Ouargla population (south-east of Algeria) in 2021, assess non-carcinogenic health risk via daily human intake, and calculate the upper acceptable fluoride concentration in drinking water by Galgan and Vermillion formula.Forty-two water samples were collected during the spring season. The fluoride was measured using a validated spectrophotometric method. Hazard quotient of fluoride (HQ) and estimated daily intake (EDI) were calculated.The results reveal a mean fluoride level of 1.07 ± 0.38 mg/L, below WHO recommendation. Fluoride concentrations in water were higher in rural areas than in the central city (p = 0.05). HQ values were less than one for adults but greater than 1 for infants and children, suggesting health risks associated with water consumption for these vulnerable groups (p = 0.007).The main contribution of this study is the establishment of a database concerning fluoride levels and hazard quotient in the south of Algeria. Monitoring drinking water and control fluorosis is essential to avoid potential health risks.

Influence of climate on groundwater fluoride in different climatic domains in a hard rock terrain of Sri Lanka: implications to community health.

Health risks associated with excessive intake of fluoride through drinking water are one of the geoenvironmental health problems observed in many parts of the world, mainly in countries of the humid tropical belt, including Sri Lanka. Fluoride-related health problems are widespread in the dry climatic region compared to the wet climatic zone of Sri Lanka. The potential health risks of fluoride for communities in a river basin which drains through two climatic zones, viz. wet and dry zones, were investigated in this study. Sixty-three groundwater samples were collected from wells in the Walawe river basin during pre- and post-monsoon periods. From collected samples, ten selected samples were analyzed for their tritium (3H) levels to find out the approximate resident time of groundwater. In the river basin, the dry zone segment is characterized by elevated levels of fluoride (> 1.0mg/L) in groundwater. Groundwater fluoride in the region was primarily of geogenic origin. The tritium values showed older groundwater contained higher fluoride levels, showing a increased dissolution of fluoride-bearing minerals. The hazard quotient (HQfluoride) showed that about 45% ofpre- and 55%of post-monsoon groundwater samples in the dry zone area were unsuitable for drinking purposes for school children who are vulnerable to non-carcinogenic risks and dental fluorosis. This study emphasizes the need for continuous water quality monitoring and mitigation measures to ensure the health of residents.

Molecular Mechanism of Changes in Gene Expression of Cytosolic Cu/Zn SOD, Lipid Peroxidation and Hepatic Function Impairments during Experimental Fluorosis

Background: Long term intake of high amount of fluoride leads to fluorosis causing metabolic, functional and structural damages affecting many tissues and organs including dental and skeletal manifestations. The liver is the most susceptible organ to fluoride toxicity because of its active and major role in digestion and detoxification.
 Aim: The present study aims to elucidate the effects of sodium fluoride on hepatic function biomarkers, lipid peroxidation and gene expression of Cu/Zn SOD in albino rats.
 Materials and Methods: Wistar albino rats were randomly assigned to three groups. The control rats were given 1 ml deionized water orally for 40 days. Groups II and III were administered 300 and 600 mg NaF/kg b.w. /day for the same period. Animals were sacrificed under anaesthesia, liver tissue was excised and used for biochemical and molecular analysis. The level of fluoride and lipid peroxidation (MDA) as well as reduced glutathione (GSH) content was determined. The activities of cytosolic copper/zinc superoxide dismutase (Cu/Zn SOD), aminotransferases (ALT and AST), lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) in the hepatic tissue were determined. The analysis of gene expression of Cu/Zn SOD in the liver was determined using Real-time PCR.
 Results: The results revealed significantly (P<0.0001) higher concentration of fluoride and MDA in the liver of rats exposed to fluoride when compared to control. The GSH content reduced significantly (P<0.0001) in fluorotic rats. The activities of hepatic function biomarkers viz; ALT, AST, LDH and ALP elevated significantly (P<0.0001) compared to the control. An elevation of 108.60% (ALP), 121.45% (AST), 33.77% (LDH) and least 24.40% (ALT) was found in rats treated with 300 mg/L fluoride and maximum elevation of 226.20% (ALP), 211.52% (AST), 57.75% (LDH) and least 56.79% (ALT) was registered in rats exposed to 600 mg/L fluoride in drinking water. The activity of cytosolic Cu/Zn SOD decreased significantly (P<0.0001) in fluorotic rats. Pearson’s bivariate correlation and simple linear regression analysis exhibited strong positive correlation between level of hepatic tissue fluoride and activities of ALT (Pearson r= 0.85), AST (Pearson r= 0.94), LDH (Pearson r= 0.89), ALP (Pearson r= 0.86) and in MDA (Pearson r=0.984) while negative correlations existed between levels of fluoride and GSH (Pearson r=-0.93) as well as activity of Cu/Zn SOD (Pearson r= -0.99). The gene expression of cytosolic Cu/Zn SOD was significantly (P<0.0001) reduced in fluorotic rats.
 Conclusion: The present study revealed that fluoride declined the antioxidant activity of hepatic Cu/Zn SOD at biochemical as well as molecular level which leads to oxidative stress and tissue damage. This further affirms by increased activities of hepatic function biomarkers in correlation with high fluoride level during experimental fluorosis.

Enhanced Defluoridation of Water Using Zirconium-Coated Pumice in Fixed-Bed Adsorption Columns.

Millions of people across the globe suffer from health issues related to high fluoride levels in drinking water. The purpose of this study was to test modified pumice as an adsorbent for the purification of fluoride-containing waters. The adsorption of fluoride onto zirconium-coated pumice (Zr–Pu) adsorbent was examined in fixed-bed adsorption columns. The coating of zirconium on the surface of VPum was revealed by X-ray diffractometer (XRD), Inductively coupled plasma-optical emission spectroscopy (ICP-EOS), and X-ray fluorescence (XRF) techniques. The degree of surface modification with the enhanced porosity of Zr–Pu was evident from the recorded scanning electron microscope (SEM) micrographs. The Brunauer-Emmett-Teller (BET) analysis confirmed the enhancement of the specific surface area of VPum after modification. The Fourier transform infrared (FTIR) examinations of VPum and Zr–Pu before and after adsorption did not reveal any significant spectrum changes. The pH drift method showed that VPum and Zr–Pu have positive charges at pHPZC lower than 7.3 and 6.5, respectively. Zr–Pu yielded a higher adsorption capacity of 225 mg/kg (2.05 times the adsorption capacity of VPum: 110 mg/kg), at pH = 2 and volumetric flow rate (QO) of 1.25 mL/min. Breakthrough time increases with decreasing pH and flow rate. The experimental adsorption data was well-matched by the Thomas and Adams-Bohart models with correlation coefficients (R2) of ≥ 0.980 (Zr–Pu) and ≥ 0.897 (VPum), confirming that both models are suitable tools to design fixed-bed column systems using volcanic rock materials. Overall, coating pumice with zirconium improved the defluoridation capacity of pumice; hence, a Zr–Pu-packed fixed-bed can be applied for defluoridation of excess fluoride from groundwater. However, additional investigations on, for instance, the influences of competing ions are advisable to draw explicit conclusions.

Is Dental Fluorosis More Prone/Susceptible to Tooth Erosion?

Background: The fluoride drug is mentioned as a double-edged weapon due to its positive and negative outcomes. Reducing dental caries in large population, cost effective and excess fluoride in teeth or body may lead to systemic diseases and even death. Dental erosion affects the hard tissues of the teeth rendering them vulnerable to decay. Methods & Materials: A school based descriptive cross-sectional survey. Purposive sampling was performed. All examiners were calibrated and trained for the criteria to identify dental fluorosis and dental erosion. The World Health Organisation Oral Health Assessment form 2013 was used to fill and measure dental fluorosis and erosive tooth wear. For Univariate analysis, mean, frequencies of both genders (dental erosion and Fluorosis) while Chi square was calculated and for bivariate analysis. Results: 22.7 % students were found to have fluorosis (ranging from questionable level to severe). Male students (primarily teenagers) had more enamel erosion as compared to the female’s ones. Conclusion: The higher levels of fluoride in water may make children and adults more susceptible to erosive tooth wear. Consuming excess fluoridated water may turn the mild fluorosis cases into moderate or severe ones. Keywords: Fluorosis, Erosive Tooth Wear, Gender, Fluoride

Spatial Distribution of Fluoride in Drinking Water in Dhamar City, Yemen

The fact that groundwater is the only source of drinking water in Yemen mandates strict monitoring of its quality. The aim of this study was to measure the levels of fluoride in the groundwater resources of Dhamar city. Dhamar city is the capital of Dhamar governorate located in the central plateau of Yemen. For this purpose, fluoride content in the groundwater from 16 wells located around Dhamar city was measured. The results showed that 75% of the investigated wells contain fluoride at or below the permissible level set by the World Health Organization (0.5 – 1.5 mg/L), whereas 25% of the wells have relatively higher fluoride concentrations (1.59 – 184 mg/L). The high levels of fluoride have been attributed to the anthropogenic activities in the residential areas near the contaminated wells. Interestingly, some wells contain very low fluoride concentrations (0.30 – 0.50 mg/L). Data were statistically treated using the principal component analysis (PCA) method to investigate any possible correlations between various factors. PCA shows a high correlation between well depth and its content of fluoride. On the other hand, health problems dominating in the study area necessitate further studies to investigate any correlation with imbalanced fluoride intake.

A Case of Fluorosis: Fluoride-Induced Osteopetrosis

There are multiple etiologies of increased bone density, including osteopetrosis and fluorosis. Osteopetrosis can either be a malignant autosomal recessive condition found in children or a benign autosomal dominant adult variant; both of which are characterized by decreased bone resorption. In contrast, fluorosis is characterized by increased bone formation secondary to chronic fluoride intoxication, but with a similar clinical manifestations to osteopetrosis.A 70-year-old lady with generalized joint aches, stiffness as well as fatigue, was found to have high bone mineral density and alarmingly high fluoride levels. The patient was found to be drinking fluoride containing water from an untreated local well for many years.Fluorosis results in increased bone mineral density and disease progression correlates with length of exposure. Fluorosis can result in reversible musculocutaneous symptoms and radiological findings. However, severe chronic cases may develop irreversible neurologic manifestations. Urinary fluoride testing is the screening modality of choice, and the key component of management is avoidance of the source of fluoride intoxication as well as monitoring of urinary fluoride levels.

Geochemical controls on the enrichment of fluoride in the mine water of the Shendong mining area, China

Underground coal mining produces large amounts of mine water annually in the Shendong mining area of China. Due to the severe scarcity of water resources, mine water is extensively used for productive, domestic, and ecological demands. However, mine water exhibits high fluoride levels. For water-use security, reduction of fluoride exposure and environmental protection, knowledge of sources and geochemical controls of fluoride enrichment in mine water is required. The results showed that F− concentrations of mine waters vary from 0.05 to 11.65 mg/L, with a mean value of 1.96 mg/L, and 51% of the mine waters contain F− concentrations exceeding the Chinese drinking water standard (1 mg/L). The overall mine water quality is influenced by cation exchange, mineral dissolution, pyrite oxidation, silicate weathering and so on. The high-fluoride mine waters are all associated with Na–type, with a remarkable cation composition feature of higher Na+ and lower Ca2+ and Mg2+ concentrations. Overall, the high-fluoride mine waters are well-matched with the water environment with higher pH, TDS, and EC levels. PCA reveals that the geochemical controls on the enrichment of F− in mine waters include dissolution of fluoride-bearing minerals and F−-OH− ion exchange; the former process is mainly caused by the decrease in Ca2+ concentrations resulting from Na + -Ca2+ cation exchange and mineral precipitation, and the latter process benefits from a highly alkaline water environment, facilitating the substitution of OH− in the mine water for F− within or absorbed on the minerals. Evaporation also controls F− enrichment in local areas.

Distribution of Fluoride in Plasma, Brain, and Bones and Associated Oxidative Damage After Induced Chronic Fluorosis in Wistar Rats.

The study was aimed to determine fluoride levels in plasma, brain, and bones of Wistar rats following chronic administration of fluoride at different dose levels and the consequent oxidative damage inflicted in these tissues. Brain histomorphology and bone radiographs were also evaluated to assess the extent of damage in these organs. Eighteen rats were randomly divided into three groups with six animals in each group. Group I served as control and groups II and III received 50 and 100ppm fluoride in tap water, respectively for 180days. A dose-dependent rise in the levels of fluoride in plasma, brain, and bones was observed in rats. Significant (P < 0.05) alterations in levels of total thiols, glutathione peroxidase, glutathione reductase, acetylcholinesterase, catalase, superoxide dismutase, lipids, as well as protein peroxidation in blood and brain were observed as compared to control in a dose-dependent manner. Radiological examination of bone revealed thinning of bone cortex with haphazard ossification, reduced bone density, and widening of marrow cavity indicating occurrence offlawed bone remodeling upon chronic fluoride exposure. Improper mineralization in bones of intoxicated rats indirectly reflected reduced bone tensile strength. Moreover, alterations in plasma Ca:P ratio and high levels of fluoride in bone ash indicated that chronic fluoride exposure leads to alterations in the bone matrix further corroborating the radio-graphical findings. Additionally, severe microscopic alterations were recorded in the cerebrum and cerebellum of treated rats which included neuronal necrosis, gliosis, spongiosis, perivascular cuffing, congestion, and hemorrhage which correlated well with oxidative changes induced by fluoride intoxication in the brain tissue of rats.

Processing Mixed Mesopelagic Biomass from the North-East Atlantic into Aquafeed Resources; Implication for Food Safety.

Aquaculture produces most of the world’s seafood and is a valuable food source for an increasing global population. Low trophic mesopelagic biomasses have the potential to sustainably supplement aquafeed demands for increased seafood production. The present study is a theoretical whole-chain feed and food safety assessment on ingredients from mesopelagic biomass and the resulting farmed fish fed these ingredients, based on analysis of processed mesopelagic biomass. Earlier theoretical estimations have indicated that several undesirable compounds (e.g., dioxins and metals and fluoride) would exceed the legal maximum levels for feed and food safety. Our measurements on processed mesopelagic biomasses show that only fluoride exceeds legal feed safety limits. Due to high levels of fluoride in crustaceans, their catch proportion will dictate the fluoride level in the whole biomass and can be highly variable. Processing factors are established that can be used to estimate the levels of undesirables in mesopelagic aquafeed ingredients from highly variable species biomass catches. Levels of most the studied undesirables (dioxins, PCBs, organochlorine pesticides, brominated flame retardant, metals, metalloids) were generally low compared to aquafeed ingredients based on pelagic fish. Using a feed-to-fillet aquaculture transfer model, the use of mesopelagic processed aquafeed ingredients was estimated to reduce the level of dioxins and PCBs by ~30% in farmed seafood such as Atlantic salmon.

Let-7c-5p Regulates CyclinD1 in Fluoride-Mediated Osteoblast Proliferation and Activation.

Endemic fluorosis is caused by the intake of high environmental fluoride, which causes dental and skeletal fluorosis. Osteoblast proliferation and activation is closely related to skeletal fluorosis and is tightly regulated by the cell cycle. Several biological processes, including bone metabolism and osteoblast proliferation and activation, are regulated by a type of noncoding RNA called microRNAs (miRNAs). However, the understanding of miRNA functions in skeletal fluorosis is limited. Based on our previous miRNA sequencing results and bioinformatics analysis, we investigated the function of the miRNA let-7c-5p to regulate CyclinD1 in fluoride-induced osteoblast proliferation and activation. We designed population experiments as well as in vitro studies using 5-Ethynyl-2'-deoxyuridine (EdU), flow cytometry, immunofluorescence, dual-luciferase reporters, and chromatin immunoprecipitation. The population-based analysis showed a decrease in let-7c-5p expression as fluoride exposure increased. In addition, let-7c-5p levels were negatively correlated with CyclinD1 and Wnt9a (another let-7c-5p target). We verified in vitro that let-7c-5p participates in the fluoride-induced proliferation and activation of human osteoblasts by directly targeting CyclinD1. Furthermore, we demonstrated that let-7c-5p regulates CyclinD1 expression via the Wnt/β-catenin signaling pathway. This study demonstrated the participation of let-7c-5p in fluoride-induced proliferation and activation of human osteoblasts by regulation of CyclinD1 expression at the post-transcriptional and transcriptional levels.

Effect of drinking high fluoride water on liver enzymes a comparitive cross-sectional study

ABSTRACT Objective: The aim of this study is to determine the effects of drinking water with high fluoride level on liver functions. Method: This is a descriptive comparative cross-sectional study conducted at Sammu rind village where the drinking water has increase fluoride content. The comparative area was Gadap town where the drinking water has normal fluoride level. Sampling was done randomly and sample size was calculated by WHO calculator and found to be 121 each for exposed and unexposed population. Blood samples taken for liver functions included bilirubin, AST, ALT, Alkaline phosphate, Gamma GT, total protein, albumin and globulin. SPSS version 16 was used for analysis. Mean and SD calculated for quantitative variable and the two comparative groups were cross-tabulated. To check the statistical significance t-test was applied. Results: There was no statistically significant difference with consideration to serum bilirubin, ALT, and AST. However, statistically significant difference was established with respect to alkaline phosphatase, Gamma GT total proteins and A/G ratio between two groups. Conclusion: In our study, there was no evidence of impaired liver function tests in subjects drinking water with high fluoride content.

JNK Signaling Pathway Mediates Fluoride-Induced Upregulation of CK1α during Enamel Formation

Fluorosis is a defect in the enamel mineral content caused by excessive fluoride intake during amelogenesis; the interaction of various factors in the development and progression of fluorosis has not been defined. Casein kinase 1α (CK1α) is constitutively active in cells and is involved in diverse cellular processes; however, its expression in fluorosis has not been measured. This study aimed to investigate the effects of fluoride on CK1α expression and to assess the regulation of molecular signaling involving fluoride and CK1α during enamel development. Kunming mice were randomly divided into the control and F groups with induced clinical features of fluorosis. The F group mice, including mothers and newborns, were treated with 50 ppm fluoridated water. Immunohistochemical staining of the sections of the embryonic mandible regions was performed at the bell stage. Protein expression and signaling pathways in a mouse-derived ameloblast-like cell line (LS8) exposed to fluoride or a Jun N-terminal kinase (JNK) inhibitor were compared to those in control cells without exposure. CK1α and proteins of the JNK signaling pathways were assayed by quantitative real-time PCR and Western blotting. Mice of the F group developed dental fluorosis. Scanning electron microscopy showed a significant reduction in the degree of mineralization in the F group mice, which manifested as thin, loosely arranged, and disorganized enamel rods. Additional analysis revealed that the expression of CK1α in the F group was significantly elevated compared with that in the control group; LS8 cells responded to fluoride by upregulation of CK1α expression through the JNK pathway. Our findings identified the potential effects of CK1α on fluorosis using a mouse model and revealed that a high fluoride level increases the expression of CK1α and that JNK can be a key regulatory factor in CK1α expression.

Exposure Assessment of Fluoride Intake Through Commercially Available Black Tea (Camellia sinensis L.) from Areas with High Incidences of Chronic Kidney Disease with Undetermined Origin (CKDu) in Sri Lanka.

Fluoride is a beneficial trace element for human health as its deficiency and excess levels can cause detrimental health effects. In Sri Lanka, dry zone regions can have excessive levels of fluoride in drinking water and can cause dental and skeletal fluorosis. In addition to drinking water, traditional habits of tea consumption can cause an additional intake of fluoride in the population. A total number of 39 locally blended black tea samples were collected from a village where chronic kidney disease with undetermined origin (CKDu) is prevalent. In addition, unblended tea samples were obtained from tea-producing factories. The fluoride contents in infusions of 2% weight per volume (w/v) were measured using calibrated ion-selective fluoride electrodes. The mean fluoride content was 2.68±1.03 mg/L in loose tea, 1.87±0.57mg/L in packed tea samples, and 1.14±0.55 mg/L in unblended tea. Repeated brewing of the same tea leaves showed that over 50% of fluoride leached into the solution in the first infusion. An estimate of the daily total average fluoride intake via tea consumption per person is 2.68 mg per day. With groundwater in many dry zone regions in Sri Lanka showing high fluoride levels that exceed 0.5 mg/L, the additional daily intake can rapidly exceed recommended thresholds of 2 mg/day. This can add to adverse health impacts that might also relate to CKDu.

The Effect of Phosphate Fertilizer on Fluoride Accumulation in Tea Leaves Based on Ecological Environment Analysis

Moderate levels of fluoride ingestion are beneficial to human health. Tea plant can accumulate fluoride. The high intake of fluoride may lead to skeletal fluorosis and dental. When the usage of phosphate fertilizer increased, the water soluble fluoride contents in the soil increased and the soil pH values decreased. The fluoride contents in the green teas were linearly related with the water soluble fluoride contents in the soil. The phosphate fertilizer, which contained high levels of fluoride, led to the high fluoride contents in the mature green teas. In developing green chemistry and green engineering, it maybe a low-cost method for the reduction the contents of fluoride in mature teas by limiting on the fluoride content in phosphate fertilizer used in the tea plantations in China.

Distribution, occurrence mechanisms, and management of high fluoride levels in the water, sediment, and soil of Shahu Lake, China

Fluoride (F−) pollution is a serious global problem. However, relatively few studies have evaluated the occurrence mechanisms of F− from an entire lake system perspective and determined their major causes via quantitative analysis. This study analyzes the distribution and occurrence mechanisms of F− in the lake water, sediment, groundwater, and soil of Shahu Lake, as well as assessing the influence of the factors on the F− in the lake water via quantitative analysis. Our results show that the F− concentrations in groundwater are higher in the eastern area of the lake, which is different from that in the surface soil layer. The F− concentrations in the lake water vary from 0.95 to 1.40 mg/L, most of which exceed Chinese standards (1 mg/L). Groundwater F− concentrations at 35% of the sampling sites exceed 1 mg/L. The total F− in the soil is significantly higher than the global mean. Ca2+-deficiency (which is mainly accelerated by cation exchange between Ca2+ and Na+) together with alkaline water conditions and intense evaporation are the major contributors of F− enrichment in groundwater. The groundwater hydrochemistry is suitable for the dissolution of F−-bearing minerals. The F− in soil is not easily leached into groundwater. Approximately 6.96 t of F− is deposited into Shahu Lake annually, where 79.17% of the F− originates from water recharge. Evaporation is the main direct cause of high F− concentrations in the lake, whereas water recharge and obstructed surface water exchange are indirect causes. To effectively decrease the F− concentrations in the lake water, water exchange within the Shahu Lake system should be enhanced, or at least 4.42 million m3 of lake water should be pumped out of the system before anthropogenic water recharge, with identically increasing volumes.

Effect of Fluoride Contaminated Groundwater on Human Health in Fluorosis Endemic Areas

Background: Fluorosis is an endemic health problem in twenty-five nations around the globe. Objectives:To correlate fluoride content of groundwater and health status of affected population and suggest remedialmeasures. Methodology: A cross-sectional research design is followed because people from different agegroups were sampled, observations were made and skeletal examinations were conducted at a specified pointof time. The study is conducted in Yavatmal and Chandrapur districts of Vidarbha region of MaharashtraState. Health related surveys were carried out in 54 villages from study area selected on the basis of highfluoride level in groundwater. Result: Out of these, 32 villages are selected from Yavatmal district havinga population of 30320 and 22 villages from Chandrapur district with a population of 21581. Out of thetotal population of 51901 total 3268 subjects have been examined. Amongst these subjects 1760 were male(53.86%) and 1508 were female (46.14%). Out of the total 3268 subjects 2445 subjects included in the‘normal’ grade, which does not show indications of skeletal fluorosis. It has been observed that as theconcentration of fluoride increases the cases of ‘normal’ grade decreases. Out of the 360 subjects studied,about 102 (28.33%) subjects show radiological evidences of skeletal fluorosis. Mild radiological fluorosiswas seen in 55, moderate in 21, severe in 17 and very severe radiological fluorosis in 9 subjects. Conclusion:Based on the outcome of the research work carried out in the study area, it is recommended that awarenessamong the people residing in the area about the protection & prevention of groundwater contamination fromdifferent sources, groundwater quality, its impacts on health, soil and plants should be created on prioritybasis.

Determination of the Fluoride Content in Water of Aqueducts of Cauca (Colombia) by Ion Exchange Chromatography.

Water for human consumption is the main source of fluoride exposure. The concentration in water should not exceed 1mg/L of fluoride since, at higher levels; it increases the risk of dental fluorosis, among other adverse effects. The fluoride content of 149 water samples from different aqueducts in Cauca (Colombia) has been determined by ion exchange chromatography with the aim of fluoride risk assessment. The rural area of the Municipality of Santander de Quilichao registered fluoride concentrations between 0.012 and 0.150mg/L. The urban area of Santander de Quilichao recorded lower fluoride levels than the rural area (0.027-0.068mg/L). The urban area of the Municipality of Cajibío registered fluoride levels of 0.082-0.186mg/L. The highest levels of fluoride were found in Timbío (0.121-0.210mg/L). The fluoride levels recorded in this study are not considered sufficient to trigger dental fluorosis. Likewise, optimal levels are not considered to protect the child population against dental caries. However, a monitoring plan of fluoride concentrations in water should be implemented to assure the quality and safe of the water.