| 1. |
- Bhattacharya, Prosun, et al.
(författare)
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Groundwater arsenic in the Lower Ganges Delta Plain in West Bengal, India and Bangladesh : A hydrogeochemical comparison
- 2010
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Ingår i: Geological Society of America. ; , s. 653-
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Arsenic contaminations in groundwater have been widely reported. The serious arsenic contamination of groundwater of Lower Ganga delta Plain (LGDP) in West Bengal, India and Bangladesh has emerged as a global natural environmental health disaster. The Bengal Delta Plain (BDP) is one of the largest deltas in the world, drained by the Ganges, Brahmaputra and Meghna river (GBM) systems. Groundwater samples were collected from 67 different sites located in the districts of 24-Parganas (S), 24-Parganas (N) and Nadia in West Bengal, India along the western margin (Bhagirathi sub-basin), and 40 different sites located in the districts of Comilla, Laxmipur, Munshiganj, Faridpur and Jhenaida districts of Bangladesh along the eastern part of the Bengal Basin (Padma-Meghna sub-basin). Groundwater in the Nadia, West Bengal is mostly of Ca–HCO3 type while in the lower part of the delta, the groundwater is of Ca-Mg-SO4 type. The concentrations of major solutes (Na+, Mg2+, Ca2+, K+, HCO3-, SO42-, NO3- and PO43- in groundwater of Meghna sub-basin is more variable than Bhagirathi sub-basin that indicating different hydrological setting in the parts of the Bengal basin. The trace element concentrations such as As, Fe and Mn also show considerable variability in the two distinct parts of the Bengal basin. Most groundwaters of the LGDP contain arsenic above the WHO and the BIS standard of 0.01 mg/L as well as in many case above the Bangladesh drinking water standard (0.05 mg/L). Both sites have moderately reducing environment, with high concentrations of dissolved organic carbon, indicating dominantly metal-reducing processes and nearly similar mechanism in As mobilization. The occurrence of elevated arsenic in groundwater is generally associated with natural biogeochemical reactions (such as reductive dissolution of iron oxides/hydroxides) by altering groundwater redox state and releasing arsenic from sediment to aqueous phase. The various redox-sensitive solutes indicate overlapping redox zones, leading to partial redox equilibrium conditions where As, once liberated from minerals of sediments, would tend to remain in groundwater because of the complex interplay among the electron acceptors. Also, microbes in organic matter environment are acting as the major electron acceptor, in the Lower Ganges Delta Plain.
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| 2. |
- Bhattacharya, Prosun, et al.
(författare)
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Temporal and seasonal variability of arsenic in drinking water wells in Matlab, southeastern Bangladesh : A preliminary evaluation on the basis of a 4 year study
- 2011
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Ingår i: Journal of Environmental Science and Health. Part A. - : Informa UK Limited. - 1093-4529 .- 1532-4117. ; 46:11, s. 1177-1184
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Tidskriftsartikel (refereegranskat)abstract
- Temporal and seasonal variability of As concentrations in groundwater were evaluated in As-affected areas of Matlab, southeastern Bangladesh. Groundwater samples from 61 randomly selected tubewells were analyzed for As concentrations over a period of three years and four months (from July 2002 to November 2005) and monitored seasonally (three times a year). The mean As concentrations in the sampled tubewells decreased from 153 to 123 mu g/L during July 2002 to November 2005. Such changes were pronounced in tubewells with As concentration >50 mu g/L than those with As concentrations <50 mu g/L. Similarly, individual wells revealed temporal variability, for example some wells indicated a decreasing trend, while some other wells indicated stable As concentration during the monitoring period. The mean As concentrations were significantly higher in Matlab North compared with Matlab South. The spatial variations in the mean As concentrations may be due to the differences in local geological conditions and groundwater flow patterns. The variations in mean As concentrations were also observed in shallow (<40 m) and deep (>40 m) wells. However, to adequately evaluate temporal and seasonal variability of As concentration, it is imperative to monitor As concentrations in tubewells over a longer period of time. Such long-term monitoring will provide important information for the assessment of human health risk and the sustainability of safe drinking water supplies.
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| 3. |
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| 4. |
- Biswas, Ashis, et al.
(författare)
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Hydrogeochemical contrast between brown and grey sand aquifers in shallow depth of Bengal Basin : consequences for sustainable drinking water supply
- 2012
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 431, s. 402-412
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Tidskriftsartikel (refereegranskat)abstract
- Delineation of safe aquifer(s) that can be targeted by cheap drilling technology for tubewell (TW) installation becomes highly imperative to ensure access to safe and sustainable drinking water sources for the arsenic (As) affected population in Bengal Basin. This study investigates the potentiality of brown sand aquifers (BSA) as a safe drinking water source by characterizing its hydrogeochemical contrast to grey sand aquifers (GSA) within shallow depth (<70 m) over an area of 100 km(2) in Chakdaha Block of Nadia district, West Bengal, India. The results indicate that despite close similarity in major ion composition, the redox condition is markedly different in groundwater of the two studied aquifers. The redox condition in the BSA is delineated to be Mn oxy-hydroxide reducing, not sufficiently lowered for As mobilization into groundwater. In contrast, the enrichments of NH4+, PO43-, Fe and As along with lower Eh in groundwater of GSA reflect reductive dis-solution of Fe oxy-hydroxide coupled to microbially mediated oxidation of organic matter as the prevailing redox process causing As mobilization into groundwater of this aquifer type. In some portions of GSA the redox status even has reached to the stage of SO42- reduction, which to some extent might sequester dissolved As from groundwater by co-precipitation with authigenic pyrite. Despite having low concentration of As in groundwater of the BSA the concentration of Mn often exceeds the drinking water guidelines, which warrants rigorous assessment of attendant health risk for Mn prior to considering mass scale exploitation of the BSA for possible sustainable drinking water supply.
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| 5. |
- Biswas, Ashis, et al.
(författare)
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Shallow hydrostratigraphy in an arsenic affected region of Bengal Basin : Implication for targeting safe aquifers for drinking water supply
- 2014
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 485, s. 12-22
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Tidskriftsartikel (refereegranskat)abstract
- To delineate arsenic (As) safe aquifer(s) within shallow depth, the present study has investigated the shallow hydrostratigraphic framework over an area of 100 km(2) at Chakdaha Block of Nadia District, West Bengal. Drilling of 29 boreholes and subsequent hydrostratigraphic modeling has identified three types of aquifer within 50 m below ground level (bgl). Aquifer-1 represents a thick paleochannel sequence, deposited parallel to the River Hooghly and Ichamati. Aquifer-2 is formed locally within the overbank deposits in the central floodplain area and its vertical extension is strictly limited to 25 m bgl. Aquifer-3 is distributed underneath the overbank deposits and represents an interfluvial aquifer of the area. Aquifer-3 is of Pleistocene age (similar to 70 ka), while aquifer-1 and 2 represent the Holocene deposits (age <951 ka), indicating that there was a major hiatus in the sediment deposition after depositing the aquifer-3. Over the area, aquifer-3 is markedly separated from the overlying Holocene deposits by successive upward sequences of brown and olive to pale blue impervious clay layers. The groundwater quality is very much similar in aquifer-1 and 2, where the concentration of As and Fe very commonly exceeds 10 mu g/L and 5 mg/L, respectively. Based on similar sediment color, these two aquifers have jointly been designated as the gray sand aquifer (GSA), which constitutes 40% (1.84 x 10(9) m(3)) of the total drilled volume (4.65 x 10(9) m(3)). In aquifer-3, the concentration of As and Fe is very low, mostly <2 mu g/L and 1 mg/L, respectively. This aquifer has been designated as the brown sand aquifer (BSA) according to color of the aquifer materials and represents 10% (4.8 x 10(8) m(3)) of the total drilled volume. This study further documents that though the concentration of As is very low at BSA, the concentration of Mn often exceeds the drinking water guidelines.
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| 6. |
- Biswas, Ashis, et al.
(författare)
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Testing tubewell platform color as a rapid screening tool for arsenic and manganese in drinking water wells
- 2012
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 46, s. 434-440
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Tidskriftsartikel (refereegranskat)abstract
- A low-cost rapid screening tool for arsenic (As) and manganese (Mn) in groundwater is urgently needed to formulate mitigation policies for sustainable drinking water supply. This study attempts to make statistical comparison between tubewell (TW)platform color and the level of As and Mn concentration in groundwater extracted from the respective TW (n = 423), to validate platform color as a screening tool for As andMnin groundwater. The result shows that a black colored platform with 73% certainty indicates that well water is safe fromAs, while with 84% certainty a red colored platform indicates that well water is enriched with As, compared to WHO drinking waterguideline of 10 μg/L. With this guideline the efficiency, sensitivity, and specificity of the tool are 79%, 77%, and 81%, respectively.However, the certainty values become 93% and 38%, respectively, for black and redcolored platforms at 50 μg/L, the drinking water standards for India and Bangladesh. The respective efficiency, sensitivity, and specificity are 65%, 85%, and 59%. Similarly for Mn, black and red colored platform with 78% and 64% certainty, respectively, indicates that wellwater is either enriched or free from Mn at the Indian national drinking water standard of 300 μg/L. With this guideline the efficiency, sensitivity, and specificity of the tool are 71%, 67%, and 76%, respectively. Thus, this study demonstrates that TWplatform color can bepotentially used as an initial screening tool for identifying TWs with elevated dissolved As andMn, tomake further rigorous groundwater testing more intensive and implement mitigation options for safe drinking water supplies.
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| 7. |
- Bundschuh, Jochen, et al.
(författare)
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Arsenic in the human food chain : the Latin American perspective
- 2012
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 429, s. 92-106
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Forskningsöversikt (refereegranskat)abstract
- Many regions of Latin America are widely reported for the occurrence of high arsenic (As) in groundwater and surface water due to a combination of geological processes and/or anthropogenic activities. In this paper, we review the available literature (both in English and Spanish languages) to delineate human As exposure pathways through the food chain. Numerous studies show that As accumulations in edible plants and crops are mainly associated with the presence of high As in soils and irrigation waters. However, factors such as As speciation, type and composition of soil, and plant species have a major control on the amount of As uptake. Areas of high As concentrations in surface water and groundwater show high As accumulations in plants, fish/shellfish, livestock meat, milk and cheese. Such elevated As concentrations in food may result in widespread health risks to local inhabitants, including health of indigenous populations and residents living close to mining industries. Some studies show that As can be transferred from the water to prepared meals, thereby magnifying the As content in the human diet. Arsenic speciation might also change during food preparation, especially during high temperature cooking, such as grilling and frying. Finally, the review of the available literature demonstrates the necessity of more rigorous studies in evaluating pathways of As exposure through the human food chain in Latin America.
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| 8. |
- Chatterjee, Debashis, et al.
(författare)
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Assessment of arsenic exposure from groundwater and rice in Bengal Delta Region, West Bengal, India
- 2010
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Ingår i: Water Research. - : Elsevier BV. - 0043-1354 .- 1879-2448. ; 44:19, s. 5803-5812
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Tidskriftsartikel (refereegranskat)abstract
- Arsenic (As) induced identifiable health outcomes are now spreading across Indian subcontinent with continuous discovery of high As concentrations in groundwater. This study deals with groundwater hydrochemistry vis-a-vis As exposure assessment among rural population in Chakdaha block, West Bengal, India. The water quality survey reveals that 96% of the tubewells exceed WHO guideline value (10 mu g/L of As). The groundwaters are generally anoxic (-283 to -22 mV) with circum-neutral pH (6.3 to 7.8). The hydrochemistry is dominated by HCO3- (208 to 440 mg/L), Ca2+ (79 to 178 mg/L) and Mg2+ (17 to 45 mg/L) ions along with high concentrations of As-T (As total, below detection limit to 0.29 mg/L), Fe-T (Fe total, 1.2 to 16 mg/L), and Fe(II) (0.74 to 16 mg/L). The result demonstrates that Fe(II)-Fe(III) cycling is the dominant process for the release of As from aquifer sediments to groundwater (and vice versa), which is mainly controlled by the local biogeochemical conditions. The exposure scenario reveals that the consumption of groundwater and rice are the major pathways of As accumulation in human body, which is explained by the dietary habit of the surveyed population. Finally, regular awareness campaign is essential as part of the management and prevention of health outcomes. (c) 2010 Elsevier Ltd. All rights reserved.
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| 9. |
- Kar, Sandeep, et al.
(författare)
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Role of organic matter and humic substances in the binding and mobility of arsenic in a Gangetic aquifer
- 2011
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Ingår i: Journal of Environmental Science and Health. Part A. - : Informa UK Limited. - 1093-4529 .- 1532-4117. ; 46:11, s. 1231-1238
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Tidskriftsartikel (refereegranskat)abstract
- Arsenic (As) enrichment in groundwater has led to extensive research, particularly on the factors responsible for its release into groundwater. In the Gangetic plain, organic matter driven microbial reduction of Fe-oxyhydroxides is considered as the most plausible mechanism of As release into groundwater. However, the role of organic matter in the aqueous environment is not well known and particularly that of organometallic complex. In this study, we have characterized bulk sediment and groundwater samples, collected from Barasat, West Bengal, India, to understand the effect of organic matter in the binding and mobility of As in the subsurface environment. The results showed a moderate correlation (R(2) = 0.49, p < 0.05) between dissolved organic carbon (DOC) and As in groundwater, suggesting that DOC has a role in releasing As into groundwater. The relative fluorescent intensity (RFI) of the dissolved humic substances in groundwater showed a maximum value of 65 QSU (mean: 47 +/- 8 QSU). FT-IR spectra of the extracted humic acid fractions of the sediment showed COO-, C = O, OH, and C = C (aromatic ring) functional groups, which may act as a chelating agents with the metal(loid)s. FT-IR spectra of the HA-As complex exhibited specific peaks at 1242 and 832 cm(-1) in the fingerprint region. This is similar to the extracted humic acid fractions of the Gangetic sediment, suggesting binding of As with humic substances.
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| 10. |
- Lin, Qi, et al.
(författare)
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Organic carbon burial in a large, deep alpine lake (southwest China) in response to changes in climate, land use and nutrient supply over the past ~100 years
- 2021
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Ingår i: Catena (Cremlingen. Print). - : Elsevier. - 0341-8162 .- 1872-6887. ; 202
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Tidskriftsartikel (refereegranskat)abstract
- Inland waterbodies play an important role in the global carbon cycle, acting both as carbon sources with organic carbon (OC) mineralization and as sinks with OC burial in sediments. Under recent impacts of global warming, anthropogenic land-use change and nutrient supply, however, there is a limited knowledge regarding OC dynamics in sediments of large, deep lakes especially in subtropical alpine regions. Here, we studied the patterns of OC burial and the potential regulating factors using multiple sedimentary proxies and observational records in Lugu Lake (southwest China) over the past ~100 years. Comparisons of 15 sediment cores in different areas of the lake reveal similar temporal trends in OC content and other sediment parameters, indicating coherent patterns of whole-lake sedimentary environmental change dominated by watershed human perturbation. Based on C/N ratios and δ13Corg analyses, the sediment OC has primarily been autochthonous in source. OC accumulation rates (OCAR) increased during 1880–1980, from ~14 to 43 g C m−2 yr−1 in a central core (LGS), mainly resulting from elevated primary production under increased phosphorus input and soil erosion. Subsequently, OCAR decreased considerably to ~15 g C m−2 yr−1, although the phosphorus supply and lake primary productivity remained high. We infer the OCAR decline likely resulted from increased organic matter decomposition and OC mineralization in the water column because of climate warming and lake-water thermal stratification. This phenomenon might mask the positive contribution of primary production to OC burial. Our findings suggest that the commonly observed synergistically positive effects of warming and eutrophication on sediment OC burial may be impaired in deep lakes, which needs further investigations across ecological, climatic and land-use gradients.
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| 11. |
- Lin, Qi, et al.
(författare)
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Spatial variation of organic carbon sequestration in large lakes and implications for carbon stock quantification
- 2022
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Ingår i: Catena (Cremlingen. Print). - : Elsevier. - 0341-8162 .- 1872-6887. ; 208
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Tidskriftsartikel (refereegranskat)abstract
- Lakes are recognized as critical zones for carbon transformation and storage, and lacustrine sediments sequestrate considerable amounts of organic carbon (OC). Understanding sedimentation processes and OC burial patterns is crucial to clarifying lakes’ role in global carbon cycling. However, OC sedimentation may be quite spatially heterogeneous within an aquatic system, owing to the differences in OC production and sources, hydrodynamic conditions and underwater topography. The uncertainties in estimating OC sequestration in the world’s large lakes remain poorly constrained. This study takes the test case of two large lakes (50 and 249 km2) with different water depth and trophic status, using a multi-core paleolimnological technique, to identify the spatial variation in OC accumulation and its main influencing factors over the past century. Results of multi-core comparisons revealed similar temporal trends in major organic and nutrient parameters, suggesting coherent processes of whole-lake sedimentary environment changes for each lake. The OC preserved in sediments was primarily of autochthonous origin. However, OC standing stocks varied ∼3-fold spatially, and average OC accumulation rates ranged between 9.5–27.4 g m−2 yr−1 (post–1963 in oligo-mesotrophic deep-lake Lugu) and between 17.4–43.5 g m−2 yr−1 (post–1980 in eutrophic shallow-lake Erhai), respectively. These variations were primarily attributable to the spatial differences in aquatic primary production and terrestrial detritus supply relating to anthropogenic land-use change and phosphorus loading, rather than intra-lake sediment focusing-related transport and redistribution. The single central-core approach from Lugu Lake would overestimate whole-lake OC stock by 32% or underestimate the value by 48%, indicating spatial variability is an important source of uncertainty for OC stock quantification in similar large and/or morphometrically complex waterbodies. Therefore, spatial heterogeneity of OC accumulation in inland waters requires considerable research with well-placed multi-cores to provide a deeper understanding of carbon sequestration patterns and mechanisms.
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| 12. |
- Liu, Chia-Chuan, et al.
(författare)
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Geochemical characteristics of the mud volcano fluids in southwestern Taiwan and their possible linkage to elevated arsenic concentration in Chianan plain groundwater
- 2012
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Ingår i: ENVIRONMENTAL EARTH SCIENCES. - : Springer Science and Business Media LLC. - 1866-6280 .- 1866-6299. ; 66:5, s. 1513-1523
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Tidskriftsartikel (refereegranskat)abstract
- Fluid and mud samples were collected from Wushanting (WST), Hsiaokunshui (HKS), Yenshuikeng (YSK), Kuantzeling (KZL), and Kunshuiping (KSP) mud volcanoes of southwestern Taiwan. Concentrations of major ions and trace elements in mud volcanic fluids were analyzed to find the possible linkage to elevated arsenic (As) concentrations in the Chianan plain groundwater. The elevated Na+, K+, and Cl- concentrations indicated possible marine origin of the fluids. The trace element concentrations in the mud volcanic fluids were generally low, but the As concentrations were up to 0.12 mg/L. High contents of As, Fe, and Mn were observed in the mud samples. Saturation index calculations indicated that both carbonate and oxide minerals acted as potential sinks for As in the mud volcanic fluids. Arsenic in the dewatering fluids and muds may be transported by the subsurface flow and surface streams as suspended solids and eventually deposited in the Chianan plain aquifers. Under reducing conditions, As may be released from the host minerals (such as Fe- and Mn-oxides/hydroxides), thereby causing widespread groundwater As pollution.
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| 13. |
- Maity, Jyoti Prakash, et al.
(författare)
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Arsenic-enriched groundwaters of India, Bangladesh and Taiwan-Comparison of hydrochemical characteristics and mobility constraints
- 2011
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Ingår i: Journal of Environmental Science and Health. Part A. - : Informa UK Limited. - 1093-4529 .- 1532-4117. ; 46:11, s. 1163-1176
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Tidskriftsartikel (refereegranskat)abstract
- Arsenic (As) enrichment in groundwater has become a major global environmental disaster. Groundwater samples were collected from 64 sites located in the districts of 24-Parganas (S), and Nadia in West Bengal, India (Bhagirathi sub-basin), and 51 sites located in the districts of Comilla, Noakhali, Magura, Brahman baria, Laxmipur, Munshiganj, Faridpur and Jhenaida in Bangladesh (Padma-Meghna sub-basin). Groundwater samples were also collected from two As-affected areas (Chianan and Lanyang plains) of Taiwan (n = 26). The concentrations of major solutes in groundwater of the Padma-Meghna sub-basin are more variable than the Bhagirathi sub-basin, suggesting variations in the depositional and hydrological settings. Arsenic concentrations in groundwaters of the studied areas showed large variations, with mean As concentrations of 125 mu g/L (range: 0.20 to 1,301 mu g/L) in Bhagirathi sub-basin, 145 mu g/L (range: 0.20 to 891 mu g/L) in Padma-Meghna sub-basin, 209 mu g/L (range: 1.3 to 575 mu g/L) in Chianan plain, and 102 mu g/L (range: 2.5 to 348 mu g/L) in Lanyang plain groundwater. The concentrations of Fe, and Mn are also highly variable, and are mostly above the WHO-recommended guideline values and local (Indian and Bangladeshi) drinking water standard. Piper plot shows that groundwaters of both Bhagirathi and Padma-Meghna sub-basins are of Ca-HCO(3) type. The Chianan plain groundwaters are of Na-Cl type, suggesting seawater intrusion, whereas Lanyang plain groundwaters are mostly of Na-HCO(3) type. The study shows that reductive dissolution of Fe(III)-oxyhydroxides is the dominant geochemical process releasing As from sediment to groundwater in all studied areas.
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| 14. |
- Maity, Jyoti Prakash, et al.
(författare)
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Arsenic-induced health crisis in peri-urban Moyna and Ardebok villages, West Bengal, India : an exposure assessment study
- 2012
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Ingår i: Environmental Geochemistry and Health. - : Springer Science and Business Media LLC. - 0269-4042 .- 1573-2983. ; 34:5, s. 563-574
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Tidskriftsartikel (refereegranskat)abstract
- Drinking of arsenic (As)-contaminated groundwater has adverse effects on health of millions of people worldwide. This study aimed to determine the degree of severity of As exposure from drinking water in peri-urban Moyna and Ardebok villages, West Bengal, India. Arsenic concentrations in hair, nail and urine samp les of the individuals were determined. Arsenical dermatosis, keratosis and melanosis were investigated through medical evaluation. We have evaluated the association between As exposure from drinking water, and keratosis and melanosis outcomes. The results showed that 82.7 % of the sampled tube wells contain As concentrations above 10 mu g/L, while 57.7 % contain As concentrations above 50 mu g/L. The hair, nail and urine As concentrations were positively correlated with As concentrations in drinking water. In our study population, we observed a strong association between As concentrations ranging 51-99 mu g/L and keratosis and melanosis outcomes, although the probability decreases at higher concentration ranges perhaps due to switching away from the use of As-contaminated tube wells for drinking and cooking purposes. High As concentrations in hair, nail and urine were observed to be associated with the age of the study population. The level of As concentrations in hair, nail and urine samples of the study population indicated the degree of severity of As exposure in the study region.
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| 15. |
- Maity, Jyoti Prakash, et al.
(författare)
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Biogeochemical characteristics of Kuan-Tzu-Ling, Chung-Lun and Bao-Lai hot springs in southern Taiwan
- 2011
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Ingår i: Journal of Environmental Science and Health. Part A. - : Informa UK Limited. - 1093-4529 .- 1532-4117. ; 46:11, s. 1207-1217
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Tidskriftsartikel (refereegranskat)abstract
- Hot springs are the important natural sources of geothermally heated groundwater from the Earth's crust. Kuan-Tzu-Ling (KTL), Chung-Lun (CL) and Bao-Lai (BL) are well-known hot springs in southern Taiwan. Fluid and mud (sediments) samples were collected from the eruption points of three hot springs for detailed biogeochemical characterization. The fluid sample displays relatively high concentrations of Na(+) and Cl(-) compared with K(+), Mg(2+), Ca(2+), NO(2)(-), and SO(4)(2-), suggesting a possible marine origin. The concentrations of Fe, Cr, Mn, Ni, V and Zn were significantly higher in the mud sediments compared with fluids, whereas high concentrations of As, Ba, Cu, Se, Sr and Rb were observed in the fluids. This suggests that electronegative elements were released during sediment-water interactions. High As concentration in the fluids was observed to be associated with low redox (Eh) conditions. The FTIR spectra of the humic acid fractions of the sediments showed the presence of possible functional groups of secondary amines, ureas, urethanesm (amide), and silicon. The sulfate-reducing deltaproteobacterium 99% similar to Desulfovibrio psychrotolerans (GU329907) were rich in the CL hot spring while mesophilic, proteolytic, thiosulfate-and sulfur-reducing bacterium that 99% similar to Clostridium sulfidigenes (GU329908) were rich in the BL hot spring.
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| 16. |
- Maity, Jyoti Prakash, et al.
(författare)
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Geothermal arsenic in Taiwan : Geochemistry and microbial diversity
- 2012
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Ingår i: UNDERSTANDING THE GEOLOGICAL AND MEDICAL INTERFACE OF ARSENIC, AS 2012. - : CRC PRESS-TAYLOR & FRANCIS GROUP. ; , s. 483-485
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Konferensbidrag (refereegranskat)abstract
- This study describes the fluid chemical compositions and related microbial diversity in geothermal systems of Taiwan. The fluid samples were collected from several geothermal springs located in northern and southern Taiwan. The pH values of the fluids showed diverse character of the geothermal systems, some are acidic in nature while few showed alkaline in nature. The fluids also contain high arsenic concentrations with As(III) as the dominant species. Yang-Ming-Shan and Beitou hot springs in northern Taiwan were characterized by sulfur spring type (contains H-SO4). The 16S rRNA gene sequence of microbial community indicated the presence of thiosulfate-oxidizing, alkaliphilic, psychrotolerant and chemo-organoheterotrophy bacterium such as Limnobacter thiooxidans, Clostridium sulfidigenes and Desulfovibrio psychrotolerans, respectively.
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