Evaluation of aqueous geochemistry of fluoride enriched groundwater: A case study of the Patan district, Gujarat, Western India (original) (raw)
Related papers
Environmental Earth Sciences, 2017
A total of 194 groundwater samples were collected from wells in hard rock aquifers of the Medak district, South India, to assess the distribution of fluoride in groundwater and to determine whether this chemical constituent was likely to be causing adverse health effects on groundwater user in the region. The study revealed that the fluoride concentration in groundwater ranged between 0.2 and 7.4 mg/L with an average concentration of 2.7 mg/L. About 57% of groundwater tested has fluoride concentrations more than the maximum permissible limit of 1.5 mg/ L. The highest concentrations of fluoride were measured in groundwater in the north-eastern part of the Medak region especially in the Siddipeta, Chinnakodur, Nanganoor and Dubhaka regions. The areas are underlain by granites which contain fluoride-bearing minerals like apatite and biotite. Due to water–rock interactions, the fluoride has become enriched in groundwater due to the weathering and leaching of fluoride-bearing minerals. The pH and bicarbonate concentrations of the groundwater are varied from 6.6 to 8.8 and 18 to 527 mg/L, respectively. High fluoride concentration in the groundwater of the study area is observed when pH and the bicarbonate concentration are high. Data plotted in Gibbs diagram show that all groundwater samples fall under rock weathering dominance group with a trend towards the evaporation dominance category. An assessment of the chemical composition of groundwater reveals that most of the groundwater samples have compositions of Ca2?–Mg2?–Cl-[Ca2?–Na?– HCO3-[Ca2?–HCO3 -[Na?–HCO3 -. This suggests that the characteristics of the groundwater flow regime, long residence time and the extent of groundwater interaction with rocks are the major factors that influence the concentration of fluoride. It is advised not to utilize the groundwater for drinking purpose in the areas delineated, and they should depend on alternate safe source.
Environmental Monitoring and Assessment, 2012
The present investigation reports the assessment of hydrochemical/geochemical processes controlling the concentration of fluoride in groundwater of a village in India (Boden block, Orissa). Boden block is one of the severely affected fluoride-contaminated areas in the state of Orissa (India). The sampling and subsequent analysis of water samples of the study area was carried out following standard prescribed methods. The results of the analysis indicate that 36.60% groundwater F − concentration exceeds the limit prescribed by the World Health Organization for drinking water. The rock interaction with groundwater containing high concentration of HCO 3 − and Na + at a higher pH value of the medium could be one of the important reasons for the release of F − from the aquatic matrix into groundwater. Geochemical classification of groundwater based on Chadha rectangular diagram shows that most of the groundwater samples having fluoride concentration more than 1.5 mg L −1 belongs to the Na-K-HCO 3 type. The saturation index values evaluated for the groundwater of the study area indicated that it is oversaturated with respect to calcite, whereas the same is undersaturated with respect to fluorite content. The deficiency of calcium ion concentration in the groundwater from calcite precipitation favors fluorite dissolution leading to excess of fluoride concentration. The risk index was calculated as a function of fluoride level in drinking water and morbidity of fluorosis categorizes high risk for villages of Amera and Karlakote panchayat of Boden block.
Springer, 2018
Groundwater is one of the most valuable natural resources in Peddavagu in Central Telangana (PCT). Most of the PCT region population rely on groundwater for especially drinking purposes. For this reason a thirty-five groundwater samples were collected, analysed various physico-chemical parameters including F −. The range of fluoride concentration 0.6-3.6 mg/L in Zone-I and 1-3.5 mg/L in Zone-II. pH of groundwater is from 7.1 to 8.4 and 7.3 to 8.3 in Zone-I and Zone-II respectively. Fluoride shows a significant correlation with pH, HCO3 − , and Na + , which may leads to enhance the fluoride content in groundwater. Insignificant relationship between F − and NO 3 − suggests no influence of anthropogenic sources for F − content in groundwater. The results of the relationship between Na + +K + versus total cations (TZ +), Ca 2+ +Mg 2+ versus HCO3 − +SO4 2− describes silicate weathering is prevails in the groundwater chemistry. The dominance of the water types Na +-HCO3 − > Ca 2+-Mg 2+-HCO3 − > Ca 2+-Mg 2+-SO 4 2− Cl − >Na +-Cl −. Gibbs plot employed to differentiate the controlling mechanisms of hydrochemistry, which showed that rock water interaction is the governing process. Na +-HCO 3 − , alkaline nature water and rock water interaction can leads to elevate fluoride content into groundwater in the study region. Thereby, most of the region people suffer with fluorosis problem, due to intake of higher fluoride content of drinking water. Therefore, the study region population may avoid such untreated water for drinking and adopt a suitable method to reduce the fluorosis problem in future.
A study on the status of fluoride ion in groundwater of coastal hard rock aquifers of south India
Arabian Journal of Geosciences, 2013
India has an increasing incidence of fluorosis, dental and skeletal, with nearly about 62 million people at risk. High fluoride groundwaters are present especially in the hard rock areas of the country. This paper analyzes the most extensive database on fluoride and other chemical constituent distribution in the coastal hard rock aquifers of Thoothukudi district. A total of 135 samples were collected and analyzed for major cations and anions to assess the geochemical process. The fluoride concentration in drinking waters varied from BDL to 3.2 mgl −1 in the study area. Majority of the samples do not comply with WHO standards for most of the water quality parameters. The saturation index of fluorite saturation index was used to correlate with F − to identify their relationship to increase of fluoride levels. The correlation between the F − concentration and the water type was also attempted. Spatial distribution of fluoride in groundwater was studied to understand the influencing factors. The relationship of F − with HCO − 3, Na + and pH concentrations were studied and found that HCO − 3 , has good correlation with F − than the other parameters.
Modeling Earth Systems and Environment, 2018
Groundwater is one of the most valuable natural resources in Peddavagu in Central Telangana (PCT). Most of the PCT region population rely on groundwater for especially drinking purposes. For this reason a thirty-five groundwater samples were collected, analysed various physico-chemical parameters including F −. The range of fluoride concentration 0.6–3.6 mg/L in Zone-I and 1–3.5 mg/L in Zone-II. pH of groundwater is from 7.1 to 8.4 and 7.3 to 8.3 in Zone-I and Zone-II respectively. Fluoride shows a significant correlation with pH, HCO 3 − , and Na + , which may leads to enhance the fluoride content in groundwater. Insignificant relationship between F − and NO 3 − suggests no influence of anthropogenic sources for F − content in groundwater. The results of the relationship between Na + +K + versus total cations (TZ +), Ca 2+ +Mg 2+ versus HCO 3 − +SO 4 2− describes silicate weathering is prevails in the groundwater chemistry. The dominance of the water types Na +-HCO 3 − > Ca 2+-Mg 2+-HCO 3 − > Ca 2+-Mg 2+-SO 4 2− Cl − >Na +-Cl −. Gibbs plot employed to differentiate the controlling mechanisms of hydrochemistry, which showed that rock water interaction is the governing process. Na +-HCO 3 − , alkaline nature water and rock water interaction can leads to elevate fluoride content into groundwater in the study region. Thereby, most of the region people suffer with fluorosis problem, due to intake of higher fluoride content of drinking water. Therefore, the study region population may avoid such untreated water for drinking and adopt a suitable method to reduce the fluorosis problem in future.
Geochemical Assessment of Fluoride Pollution in Groundwater of Tribal Region in India
Bulletin of environmental contamination and toxicology, 2018
This study assessed the fluoride (F-) pollution in groundwater samples (n = 170) of tribal regions around Bailadila Iron Ore Mines [BIOM] Complex of Dantewada District, India. Weathering of carbonate and silicate clays were important geogenic sources of dissolved ions. A Piper diagram showed a Ca-HCO3 water type, with positive chloro-alkaline indices illustrating the occurrence of direct base-exchange reactions. The F- concentrations varied from 0.08 to 1.95 mg L-1 with a mean value of 0.9 ± 0.3 mg L-1. Only two groundwater samples showed F- concentrations > 1.5 mg L-1, the drinking water guideline established by the World Health Organization (WHO) and Bureau of Indian Standards (BIS). Factor analysis showed high loadings of HCO3- and F-, indicating alkaline conditions, favoring the dissolution of F- in the groundwater. The K fluor value is less than 10-10.6, indicating that the dissociation of fluorite is very slow. As a result, groundwater locations were under-saturated with re...
The aim of the present study is to identify the geochemical processes responsible for higher fluoride (F –) content in the groundwater of the Yellareddigudem watershed located in Nalgonda district, Andhra Pradesh. The basement rocks in the study area comprise mainly of granites (pink and grey varieties), which contain F-bearing minerals (fluorite, biotite and hornblende). The results of the study area suggest that the groundwater is characterized by Na + : HCO facies. The F – content varies from 0.42 to 7.50 mg/L. In about 68% of the collected groundwater samples, the concentration of F – exceeds the national drinking water quality limit of 1.5 mg/L. The weathering of the granitic rocks causes the release of Na + and HCO ions, which increase the solubility of ions. Ion exchange between Na + and Ca 2+ , and precipitation of CaCO 3 reduce the activity of Ca 2+. This favours dissolution of CaF 2 from the F-bearing minerals present in the host rocks, leading to a higher concentration of F – in the groundwater. The study further suggests that the spatial variation in the F – content appears to be caused by difference in the relative occurrence of F-bearing minerals, the degree of rock-weathering and fracturing, the residence time of water in the aquifer materials and the associated geochemical processes. The study emphasizes the need for appropriate management measures to mitigate the effect of higher F groundwater on human health.
The present study has been carried out covering two blocks—Suri I and II in Birbhum district, West Bengal, India. The evaluation focuses on occurrence, distribution and geochemistry in 26 water samples collected from borewells spread across the entire study area homogeneously. Quantitative chemical analysis of groundwater samples collected from the present study area has shown that samples from two locations—Gangta and Dhalla contain fluoride greater than the permissible limit prescribed by WHO during both post-monsoon and pre-monsoon sampling sessions. Significant factor controlling geochemistry of groundwater has been identified to be rock–water interaction processes during both sampling sessions based on the results of Gibb’s diagrams. Geochemical modeling studies have revealed that fluorite (CaF2) is, indeed, present as a significant fluoride-bearing mineral in the groundwaters of this study area. Calcite or CaCO3 is one of the most common minerals with which fluorite remains associated, and saturation index calculations have revealed that the calcite–fluorite geochemistry is the dominant factor controlling fluoride concentration in this area during both post- and pre-monsoon. High fluoride waters have also been found to be of ‘bicarbonate’ type showing increase of sodium in water with decrease of calcium. Keywords Groundwater Fluoride Geochemistry Suri
Applied Water Science , 2017
Hydrogeochemical investigation has been carried out in the granitic terrain of Siddipet area, Medak district, Telangana State, India with an aim to understand the distribution of fluoride in the groundwater and to understand the relationship of fluoride with other major ions, and also to identify the high fluoride-bearing groundwater zones. 104 groundwater samples were analyzed in the study area for fluoride and other major ions like calcium, magnesium, chloride, carbonate, bicarbonate, sodium, potassium, sulfate, and nitrate in addition to pH and electrical conductivity. The studies revealed that the concentration of fluoride in groundwater is ranging from 0.2 to 2.2 mg L-1 with a mean of 1.1 mg L-1. Nearly 22 % of groundwater has more than the permissible limit of fluoride (1.5 mg L-1), which is responsible for the endemic dental fluorosis in the area concerned. Geo-chemical classification of groundwater shows that Na– HCO 3 , Ca–Cl, and Ca–HCO 3 –Na are the dominant hydrochemical facies. Gibbs diagram shows rock–water interaction dominance and evaporation dominance, which are responsible for the change in the quality of water in the hard rock aquifer of the study area. The groundwater in villages and its environs are affected by fluoride contamination , and consequently majority of the population living in these villages suffer from dental fluorosis. Hence, they are advised to consume drinking water which has less than 1.5 mg L-1 fluoride to avoid further fluorosis risks.