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Feng F, Jiang Y, Jia Y, Lian X, Shang C, Zhao M. Exogenous-organic-matter-driven mobilization of groundwater arsenic. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2023; 15:100243. [PMID: 36896144 PMCID: PMC9989647 DOI: 10.1016/j.ese.2023.100243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 01/21/2023] [Accepted: 01/24/2023] [Indexed: 06/18/2023]
Abstract
The potential release capacity of arsenic (As) from sediment was evaluated under a high level of exogenous organic matter (EOM) with both bioreactive and chemically reactive organic matters (OMs). The OMs were characterized by FI, HIX, BIX, and SUVA254 fluorescence indices showing the biological activities were kept at a high level during the experimental period. At the genus level, Fe/Mn/As-reducing bacteria (Geobacter, Pseudomonas, Bacillus, and Clostridium) and bacteria (Paenibacillus, Acidovorax, Delftia, and Sphingomonas) that can participate in metabolic transformation using EOM were identified. The reducing condition occurs which promoted As, Fe, and Mn releases at very high concentrations of OM. However, As release increased during the first 15-20 days, followed by a decline contributed by secondary iron precipitation. The degree of As release may be limited by the reactivity of Fe (hydro)oxides. The EOM infiltration enhances As and Mn releases in aqueous conditions causing the risk of groundwater pollution, which could occur in specific sites such as landfills, petrochemical sites, and managed aquifer recharge projects.
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Affiliation(s)
- Fan Feng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Yonghai Jiang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Yongfeng Jia
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Xinying Lian
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Changjian Shang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Meng Zhao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
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Distribution and Geochemical Controls of Arsenic and Uranium in Groundwater-Derived Drinking Water in Bihar, India. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17072500. [PMID: 32268538 PMCID: PMC7177302 DOI: 10.3390/ijerph17072500] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/01/2020] [Accepted: 04/02/2020] [Indexed: 11/17/2022]
Abstract
Chronic exposure to groundwater containing elevated concentrations of geogenic contaminants such as arsenic (As) and uranium (U) can lead to detrimental health impacts. In this study, we have undertaken a groundwater survey of representative sites across all districts of the State of Bihar, in the Middle Gangetic Plain of north-eastern India. The aim is to characterize the inorganic major and trace element aqueous geochemistry in groundwater sources widely used for drinking in Bihar, with a particular focus on the spatial distribution and associated geochemical controls on groundwater As and U. Concentrations of As and U are highly heterogeneous across Bihar, exceeding (provisional) guideline values in ~16% and 7% of samples (n = 273), respectively. The strongly inverse correlation between As and U is consistent with the contrasting redox controls on As and U mobility. High As is associated with Fe, Mn, lower Eh and is depth-dependent; in contrast, high U is associated with HCO3−, NO3− and higher Eh. The improved understanding of the distribution and geochemical controls on As and U in Bihar has important implications on remediation priorities and selection, and may contribute to informing further monitoring and/or representative characterization efforts in Bihar and elsewhere in India.
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Galloway JM, Swindles GT, Jamieson HE, Palmer M, Parsons MB, Sanei H, Macumber AL, Timothy Patterson R, Falck H. Organic matter control on the distribution of arsenic in lake sediments impacted by ~65years of gold ore processing in subarctic Canada. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 622-623:1668-1679. [PMID: 29111252 DOI: 10.1016/j.scitotenv.2017.10.048] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 10/02/2017] [Accepted: 10/06/2017] [Indexed: 05/26/2023]
Abstract
Climate change is profoundly affecting seasonality, biological productivity, and hydrology in high northern latitudes. In sensitive subarctic environments exploitation of mineral resources led to contamination and it is not known how cumulative effects of resource extraction and climate warming will impact ecosystems. Gold mines near Yellowknife, Northwest Territories, subarctic Canada, operated from 1938 to 2004 and released >20,000t of arsenic trioxide (As2O3) to the environment through stack emissions. This release resulted in elevated arsenic concentrations in lake surface waters and sediments relative to Canadian drinking water standards and guidelines for the protection of aquatic life. A meta-analytical approach is used to better understand controls on As distribution in lake sediments within a 30-km radius of historic mineral processing activities. Arsenic concentrations in the near-surface sediments range from 5mg·kg-1 to over 10,000mg·kg-1 (median 81mg·kg-1; n=105). Distance and direction from the historic roaster stack are significantly (p<0.05) related to sedimentary As concentration, with highest As concentrations in sediments within 11km and lakes located downwind. Synchrotron-based μXRF and μXRD confirm the persistence of As2O3 in near surface sediments of two lakes. Labile organic matter (S1) is significantly (p<0.05) related to As and S concentrations in sediments and this relationship is greatest in lakes within 11km from the mine. These relations are interpreted to reflect labile organic matter acting as a substrate for microbial growth and mediation of authigenic precipitation of As-sulphides in lakes close to the historic mine where As concentrations are highest. Continued climate warming is expected to lead to increased biological productivity and changes in organic geochemistry of lake sediments that are likely to play an important role in the mobility and fate of As in aquatic ecosystems.
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Affiliation(s)
- Jennifer M Galloway
- Natural Resources Canada/Ressources naturelles Canada Geological Survey of Canada/Commission géologique du Canada, 3303 33rd Street N.W., Calgary, Ab, T2L 2A7, Canada.
| | - Graeme T Swindles
- School of Geography, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Heather E Jamieson
- Department of Geological Sciences and Geological Engineering, Queen's University, Kingston, ON, KL7 3N6, Canada
| | - Michael Palmer
- NWT Cumulative Impact Monitoring Program, Government of the Northwest Territories, Yellowknife, NT, X1A 2R3, Canada
| | - Michael B Parsons
- Natural Resources Canada/Ressources naturelles Canada Geological Survey of Canada/Commission géologique du Canada, 1 Challenger Drive, Dartmouth, NS, B2Y 4A2, Canada
| | - Hamed Sanei
- Natural Resources Canada/Ressources naturelles Canada Geological Survey of Canada/Commission géologique du Canada, 3303 33rd Street N.W., Calgary, Ab, T2L 2A7, Canada
| | - Andrew L Macumber
- Department of Earth Sciences, Carleton University, Ottawa, ON, K1S 5B6, Canada
| | - R Timothy Patterson
- Department of Earth Sciences, Carleton University, Ottawa, ON, K1S 5B6, Canada
| | - Hendrik Falck
- Northwest Territories Geological Survey, Yellowknife, NT, X1A 2R3, Canada
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Radloff KA, Zheng Y, Stute M, Weinman B, Bostick B, Mihajlov I, Bounds M, Rahman MM, Huq MR, Ahmed KM, Schlosser P, van Geen A. Reversible adsorption and flushing of arsenic in a shallow, Holocene aquifer of Bangladesh. APPLIED GEOCHEMISTRY : JOURNAL OF THE INTERNATIONAL ASSOCIATION OF GEOCHEMISTRY AND COSMOCHEMISTRY 2017; 77:142-157. [PMID: 28458447 PMCID: PMC5404749 DOI: 10.1016/j.apgeochem.2015.11.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The spatial heterogeneity of dissolved arsenic (As) concentrations in shallow groundwater of the Bengal Basin has been attributed to transport of As (and reactive carbon) from external sources or to the release of As from within grey sand formations. We explore the latter scenario in this detailed hydrological and geochemical study along a 300 m transect of a shallow aquifer extending from a groundwater recharge area within a sandy channel bar to its discharge into a nearby stream. Within the 10-20 m depth range, groundwater ages along the transect determined by the 3H-3He method increase from <10 yr in the recharge area to a maximum of 40 yr towards the stream. Concentrations of groundwater As within the same grey sands increase from 10 to 100 to ∼500 µg/L along this transect. Evidence of reversible adsorption of As between the groundwater and sediment was obtained from a series of push-pull experiments, traditional batch adsorption experiments, and the accidental flooding of a shallow monitoring well. Assuming reversible adsorption and a distribution coefficient, Kd, of 0.15-1.5 L/kg inferred from these observations, a simple flushing model shows that the increase in As concentrations with depth and groundwater age at this site, and at other sites in the Bengal and Red River Basins, can be attributed to the evolution of the aquifer over 100-1000 years as aquifer sands are gradually flushed of their initial As content. A wide range of As concentrations can thus be maintained in groundwater with increases with depth governed by the history of flushing and local recharge rates, without external inputs of reactive carbon or As from other sources.
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Affiliation(s)
- Kathleen A. Radloff
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
- Columbia University, New York, NY 10027, USA
- Corresponding author. Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA., (K.A. Radloff)
| | - Yan Zheng
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
- Queens College, City University of New York, Flushing, NY 11367, USA
| | - Martin Stute
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
- Barnard College, Columbia University, New York, NY 10027, USA
| | | | - Benjamin Bostick
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
| | | | - Margaret Bounds
- Barnard College, Columbia University, New York, NY 10027, USA
| | - M. Moshiur Rahman
- Queens College, City University of New York, Flushing, NY 11367, USA
- Department of Geology, University of Dhaka, Dhaka, Bangladesh
| | - M. Rezaul Huq
- Department of Geology, University of Dhaka, Dhaka, Bangladesh
| | - Kazi M. Ahmed
- Department of Geology, University of Dhaka, Dhaka, Bangladesh
| | - Peter Schlosser
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
- Columbia University, New York, NY 10027, USA
| | - Alexander van Geen
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
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Aziz Z, Bostick B, Zheng Y, Huq M, Rahman M, Ahmed K, van Geen A. Evidence of Decoupling between Arsenic and Phosphate in Shallow Groundwater of Bangladesh and Potential Implications. APPLIED GEOCHEMISTRY : JOURNAL OF THE INTERNATIONAL ASSOCIATION OF GEOCHEMISTRY AND COSMOCHEMISTRY 2017; 77:167-177. [PMID: 28239232 PMCID: PMC5321624 DOI: 10.1016/j.apgeochem.2016.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Reductive dissolution of iron oxyhydroxides and reduction of arsenic are often invoked as leading causes of high dissolved As levels in shallow groundwater of Bangladesh. The second of these assumptions is questioned here by comparing the behavior As and phosphate (P), a structural analogue for As (V) which also adsorbs strongly to Fe oxyhydroxides but is not subject to reduction. The first line of evidence is provided by a detailed groundwater time-series spanning two years for three wells in the 6-9 m depth range showing removal of As(III) from shallow groundwater during the monsoon without of loss of P. The data indicate a loss of ~90% of the dissolved As from groundwater in the intermediate well relative to a level of 3 μmol/L As predicted by conservative mixing between groundwater sampled from the shallower and the deeper well. In contrast, P concentrations of ~30 μmol/L in the intermediate well closely match the prediction from conservative mixing. Reduction therefore appears to inhibit the release of As to groundwater at this site relative to P instead of enhancing it. A re-analysis of existing groundwater As and P data from across the country provides a broader context for this finding and confirms that, without reduction, elevated concentrations of As would probably be even more widespread in shallow aquifers of Bangladesh. Without providing definite proof, X-ray absorption spectroscopy of sediment from the time-series site and elsewhere suggests that the loss of As from groundwater may be coupled to precipitation of As sulfide. Further study is needed to assess the implications of these observations for shallow aquifers that have been subjected to increased withdrawals for irrigation in recent decades.
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Affiliation(s)
- Z. Aziz
- Department of Earth and Environmental Sciences, Columbia University, New York, NY 10027, USA
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
| | - B.C. Bostick
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
| | - Y. Zheng
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
- School of Earth and Environmental Sciences, Queens College of the City University of New York, Flushing, NY 11367, USA
| | - M.R. Huq
- Department of Geology, University of Dhaka, 1000 Dhaka, Bangladesh
| | - M.M. Rahman
- Department of Geology, University of Dhaka, 1000 Dhaka, Bangladesh
| | - K.M. Ahmed
- Department of Geology, University of Dhaka, 1000 Dhaka, Bangladesh
| | - A. van Geen
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
- Corresponding author: , Phone: +1 845 365 8644, Fax: +1 845 365 8154
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Jung HB, Zheng Y, Rahman MW, Rahman MM, Ahmed KM. Redox Zonation and Oscillation in the Hyporheic Zone of the Ganges-Brahmaputra-Meghna Delta: Implications for the Fate of Groundwater Arsenic during Discharge. APPLIED GEOCHEMISTRY : JOURNAL OF THE INTERNATIONAL ASSOCIATION OF GEOCHEMISTRY AND COSMOCHEMISTRY 2015; 63:647-660. [PMID: 26855475 PMCID: PMC4740924 DOI: 10.1016/j.apgeochem.2015.09.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Riverbank sediment cores and pore waters, shallow well waters, seepage waters and river waters were collected along the Meghna Riverbank in Gazaria Upazila, Bangladesh in Jan. 2006 and Oct.-Nov. 2007 to investigate hydrogeochemical processes controlling the fate of groundwater As during discharge. Redox transition zones from suboxic (0-2 m depth) to reducing (2-5 m depth) then suboxic conditions (5-7 m depth) exist at sites with sandy surficial deposits, as evidenced by depth profiles of pore water (n=7) and sediment (n=11; diffuse reflectance, Fe(III)/Fe ratios and Fe(III) concentrations). The sediment As enrichment zone (up to ~700 mg kg-1) is associated with the suboxic zones mostly between 0-2 m depth and less frequently between 5-7 m depth. The As enriched zones consist of several 5 to 10 cm-thick dispersed layers and span a length of ~5-15 m horizontally from the river shore. Depth profiles of riverbank pore water deployed along a 32 m transect perpendicular to the river shore show elevated levels of dissolved Fe (11.6±11.7 mg L-1) and As (118±91 μg L-1, mostly as arsenite) between 2-5 m depth, but lower concentrations between 0-2 m depth (0.13±0.19 mg L-1 Fe, 1±1 μg L-1 As) and between 5-6 m depth (1.14±0.45 mg L-1 Fe, 28±17 μg L-1 As). Because it would take more than a few hundred years of steady groundwater discharge (~10 m yr-1) to accumulate hundreds of mg kg-1 of As in the riverbank sediment, it is concluded that groundwater As must have been naturally elevated prior to anthropogenic pumping of the aquifer since the 1970s. Not only does this lend unequivocal support to the argument that As occurrence in the Ganges-Brahmaputra-Meghna Delta groundwater is of geogenic origin, it also calls attention to the fate of this As enriched sediment as it may recycle As into the aquifer.
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Affiliation(s)
- Hun Bok Jung
- School of Earth and Environmental Sciences, Queens College and the Graduate School and University Center, The City University of New York, Flushing, New York 11367, USA
| | - Yan Zheng
- School of Earth and Environmental Sciences, Queens College and the Graduate School and University Center, The City University of New York, Flushing, New York 11367, USA
- Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, New York 10964, USA
| | | | | | - Kazi M. Ahmed
- Department of Geology, University of Dhaka, Dhaka 1000, Bangladesh
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Arsenic-safe aquifers as a socially acceptable source of safe drinking water—What can rural Latin America learn from Bangladesh experiences? ACTA ACUST UNITED AC 2012. [DOI: 10.1201/b11334-90] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Farooq SH, Chandrasekharam D, Berner Z, Norra S, Stüben D. Influence of traditional agricultural practices on mobilization of arsenic from sediments to groundwater in Bengal delta. WATER RESEARCH 2010; 44:5575-5588. [PMID: 20655567 DOI: 10.1016/j.watres.2010.05.057] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2010] [Revised: 05/06/2010] [Accepted: 05/31/2010] [Indexed: 05/29/2023]
Abstract
In the wake of the idea that surface derived dissolved organic carbon (DOC) plays an important role in the mobilization of arsenic (As) from sediments to groundwater and may provide a vital tool in understanding the mechanism of As contamination (mobilization/fixation) in Bengal delta; a study has been carried out. Agricultural fields that mainly cultivate rice (paddy fields) leave significantly large quantities of organic matter/organic carbon on the surface of Bengal delta which during monsoon starts decomposing and produces DOC. The DOC thus produced percolates down with rain water and mobilizes As from the sediments. Investigations on sediment samples collected from a paddy field clearly indicate that As coming on to the surface along with the irrigation water accumulates itself in the top few meters of sediment profile. The column experiments carried out on a 9 m deep sediment profile demonstrates that DOC has a strong potential to mobilize As from the paddy fields and the water recharging the aquifer through such agricultural fields contain As well above the WHO limit thus contaminating the shallow groundwater. Experiment also demonstrates that decay of organic matter induces reducing condition in the sediments. Progressively increasing reducing conditions not only prevent the adsorption of As on mineral surfaces but also cause mobilization of previously sorbed arsenic. There seems to be a cyclic pattern where As from deeper levels comes to the surface with irrigational water, accumulates itself in the sediments, and ultimately moves down to the shallow groundwater. The extensive and continual exploitation of intermediate/deep groundwater accelerates this cyclic process and helps in the movement of shallow contaminated groundwater to the deeper levels.
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Affiliation(s)
- S H Farooq
- Institute of Mineralogy and Geochemistry, Karlsruhe Institute of Technology (KIT), Karlsruhe 76131, Germany.
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Burnol A, Charlet L. Fe(II)-Fe(III)-bearing phases as a mineralogical control on the heterogeneity of arsenic in Southeast Asian groundwater. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:7541-7547. [PMID: 20831208 DOI: 10.1021/es100280h] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Although groundwater arsenic constitutes a major hazard to the health of the people of Southeast Asia, the exact mineralogical origin of the arsenic in these fluvial aquifers is still under debate. Fe(III) oxides are the dominant hosts of mobilizable arsenic in the sediments, with the role of secondary Fe(II)-bearing phases like mackinawite, siderite, vivianite, magnetite, and carbonate green rust (fougerite) still unclear. Based on published field data from Chakdaha (India), the importance of the phases for arsenic mobility is evaluated quantitatively using models of growing complexity. Arsenic heterogeneity can be explained by the presence of two contrasted redox zones in the aquifers, with Fe(III) oxides being the dominant sorbent for arsenic in the less reduced zones and Fe(II) sulfides and/or Fe(II) carbonates being the solid-phase hosts for arsenic under more reduced conditions below impermeable soils or close to rivers where sulfate is reduced. A 1D reactive transport model which simulates the transition between the two environments has been developed and compared to field data. The results show that microbial sulfate reduction followed by abiotic and/or biotic reduction of As(III)-bearing iron oxides accounts for the spatial heterogeneity of arsenic in such reduced aquifers.
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Affiliation(s)
- Andre Burnol
- LGIT-OSUG, University of Grenoble-I, BP 53, 38041 Grenoble Cedex 9, France.
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10
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Spangler AH, Spangler JG. Groundwater manganese and infant mortality rate by county in North Carolina: an ecological analysis. ECOHEALTH 2009; 6:596-600. [PMID: 20232227 DOI: 10.1007/s10393-010-0291-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Revised: 12/30/2009] [Accepted: 01/20/2010] [Indexed: 05/28/2023]
Abstract
Manganese is an element essential in trace quantities but toxic in high concentrations. As a naturally occurring element in groundwater and a chemical of increasing global significance due to its growing trend of replacing lead in gasoline, vigilant assessment of its detrimental effects is essential. In response to previous research that showed a potential link between manganese and well water, we performed a pilot ecological study using data obtained from the North Carolina Center for Health Statistics, the North Carolina Geological Survey, and the U.S. Census. Our pilot study investigated the relationship between logarithmically transformed county level groundwater manganese concentrations with county level infant mortality rates (reported as deaths/1,000) within the state of North Carolina (n = 100 counties; North Carolina 2000 population = 8,049,313) using stepwise, multiple regression. Our model accounted for such confounders as low birth weight, economic status, education, and ethnicity. Across North Carolina counties, for every log increase in groundwater manganese concentration, there was a 2.074 increase in county level infant deaths per 1,000 live births. This study is the first to show on a statewide basis adverse infant mortality effects of environmental manganese. These pilot data argue for further research into a broad range of developmental effects and also may be useful to regulatory agencies interested in protecting communities' health.
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Affiliation(s)
- Andrew H Spangler
- Department of Family and Community Medicine, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA.
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Arora M, Megharaj M, Naidu R. Arsenic testing field kits: some considerations and recommendations. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2009; 31 Suppl 1:45-8. [PMID: 19085061 DOI: 10.1007/s10653-008-9231-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2007] [Revised: 09/16/2008] [Accepted: 10/17/2008] [Indexed: 05/25/2023]
Abstract
In recent years field test kits have been largely used to identify arsenic (As) levels in contaminated water sources in Bangladesh, West Bengal (India), and elsewhere in the world to establish whether or not the water is safe. Most of the kits are based on the reaction of arsine gas with some chemical agent to form a coloured complex; the intensity of the colour is compared visually with a colour-coded chart or measured electronically to calculate the concentration of As in the water sample. In this paper, a step-wise review is presented of the analytical process used in the most commonly available As field test kits and the associated shortcomings of each of these kits. We also identify the research gaps for future work to enhance the accuracy and reliability of test results produced by these kits.
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Affiliation(s)
- Meenakshi Arora
- Department of Natural Resources, India Habitat Centre, TERI University, New Delhi, India.
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12
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Microbial mineral weathering for nutrient acquisition releases arsenic. Appl Environ Microbiol 2009; 75:2558-65. [PMID: 19251899 DOI: 10.1128/aem.02440-07] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tens of millions of people in Southeast Asia drink groundwater contaminated with naturally occurring arsenic. How arsenic is released from the sediment into the water remains poorly understood. Here, we show in laboratory experiments that phosphate-limited cells of Burkholderia fungorum mobilize ancillary arsenic from apatite. We hypothesize that arsenic mobilization is a by-product of mineral weathering for nutrient acquisition. The released arsenic does not undergo a redox transformation but appears to be solubilized from the apatite mineral lattice during weathering. Analysis of apatite from the source area in the Himalayan basin indicates the presence of elevated levels of arsenic, with an average concentration of 210 mg/kg. The rate of arsenic release is independent of the initial dissolved arsenic concentration and occurs at phosphate levels observed in Bangladesh aquifers. We also demonstrate the presence of the microbial phenotype that releases arsenic from apatite in Bangladesh aquifer sediments and groundwater. These results suggest that microbial mineral weathering for nutrient acquisition could be an important mechanism for arsenic mobilization.
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Radloff KA, Manning AR, Mailloux B, Zheng Y, Rahman MM, Huq MR, Ahmed KM, van Geen A. Considerations for conducting incubations to study the mechanisms of As release in reducing groundwater aquifers. APPLIED GEOCHEMISTRY : JOURNAL OF THE INTERNATIONAL ASSOCIATION OF GEOCHEMISTRY AND COSMOCHEMISTRY 2008; 23:3224-3235. [PMID: 19884962 PMCID: PMC2614277 DOI: 10.1016/j.apgeochem.2008.07.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Microbial Fe reduction is widely believed to be the primary mechanism of As release from aquifer sands in Bangladesh, but alternative explanations have been proposed. Long-term incubation studies using natural aquifer material are one way to address such divergent views. This study addresses two issues related to this approach: (1) the need for suitable abiotic controls and (2) the spatial variability of the composition of aquifer sands. Four sterilization techniques were examined using orange-colored Pleistocene sediment from Bangladesh and artificial groundwater over 8 months. Acetate (10 mM) was added to sacrificial vials before sterilization using either (1) 25 kGy of gamma irradiation, (2) three 1-h autoclave cycles, (3) a single addition of an antibiotic mixture at 1x or (4) 10x the typical dose, and (5) a 10 mM addition of azide. The effectiveness of sterilization was evaluated using two indicators of microbial Fe reduction, changes in diffuse spectral reflectance and leachable Fe(II)/Fe ratios, as well as changes in P-extractable As concentrations in the solid phase. A low dose of antibiotics was ineffective after 70 days, whereas autoclaving significantly altered groundwater composition. Gamma irradiation, a high dose of antibiotics, and azide were effective for the duration of the experiment.
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Affiliation(s)
- Kathleen A. Radloff
- Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027, USA
- Corresponding author:
| | - Anya R. Manning
- Barnard College, Columbia University, New York, NY 10027, USA
| | - Brian Mailloux
- Barnard College, Columbia University, New York, NY 10027, USA
| | - Yan Zheng
- Queen’s College, City University of New York, Flushing, NY 11367, USA
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964
| | | | - M. Rezaul Huq
- Department of Geology, University of Dhaka, Dhaka, Bangladesh
| | - Kazi M. Ahmed
- Department of Geology, University of Dhaka, Dhaka, Bangladesh
| | - Alexander van Geen
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964
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14
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van Geen A, Radloff K, Aziz Z, Cheng Z, Huq M, Ahmed K, Weinman B, Goodbred S, Jung H, Zheng Y, Berg M, Trang P, Charlet L, Metral J, Tisserand D, Guillot S, Chakraborty S, Gajurel A, Upreti B. Comparison of arsenic concentrations in simultaneously-collected groundwater and aquifer particles from Bangladesh, India, Vietnam, and Nepal. APPLIED GEOCHEMISTRY : JOURNAL OF THE INTERNATIONAL ASSOCIATION OF GEOCHEMISTRY AND COSMOCHEMISTRY 2008; 23:3019-3028. [PMID: 19884967 PMCID: PMC2630228 DOI: 10.1016/j.apgeochem.2008.07.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
One of the reasons the processes resulting in As release to groundwater in southern Asia remain poorly understood is the high degree of spatial variability of physical and chemical properties in shallow aquifers. In an attempt to overcome this difficulty, a simple device that collects groundwater and sediment as a slurry from precisely the same interval was developed in Bangladesh. Recently published results from Bangladesh and India relying on the needle-sampler are augmented here with new data from 37 intervals of grey aquifer material of likely Holocene age in Vietnam and Nepal. A total of 145 samples of filtered groundwater ranging in depth from 3 to 36 m that were analyzed for As (1-1000 mug/L), Fe (0.01-40 mg/L), Mn (0.2-4 mg/L) and S (0.04-14 mg/L) are compared. The P-extractable (0.01-36 mg/kg) and HCl-extractable As (0.04-36 mg/kg) content of the particulate phase was determined in the same suite of samples, in addition to Fe(II)/Fe ratios (0.2-1.0) in the acid-leachable fraction of the particulate phase. Needle-sampler data from Bangladesh indicated a relationship between dissolved As in groundwater and P-extractable As in the particulate phase that was interpreted as an indication of adsorptive equilibrium, under sufficiently reducing conditions, across 3 orders of magnitude in concentrations according to a distribution coefficient of 4 mL/g. The more recent observations from India, Vietnam and Nepal show groundwater As concentrations that are often an order of magnitude lower at a given level of P-extractable As compared to Bangladesh, even if only the subset of particularly reducing intervals characterized by leachable Fe(II)/Fe >0.5 and dissolved Fe >0.2 mg/L are considered. Without attempting to explain why As appears to be particularly mobile in reducing aquifers of Bangladesh compared to the other regions, the consequences of increasing the distribution coefficient for As between the particulate and dissolved phase to 40 mL/g for the flushing of shallow aquifers of their initial As content are explored.
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Affiliation(s)
- A. van Geen
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
- Corresponding author:
| | - K. Radloff
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
| | - Z. Aziz
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
| | - Z. Cheng
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
| | - M.R. Huq
- Department of Geology, University of Dhaka, Bangladesh
| | - K.M. Ahmed
- Department of Geology, University of Dhaka, Bangladesh
| | - B. Weinman
- Earth & Environmental Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - S. Goodbred
- Earth & Environmental Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - H.B. Jung
- Queens College, City University of New York, Flushing, New York, USA
| | - Y. Zheng
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, USA
- Queens College, City University of New York, Flushing, New York, USA
| | - M. Berg
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dubendorf, Switzerland
| | | | - L. Charlet
- LGIT-OSUG, University of Grenoble, Grenoble, France
| | - J. Metral
- LGIT-OSUG, University of Grenoble, Grenoble, France
| | - D. Tisserand
- LGIT-OSUG, University of Grenoble, Grenoble, France
| | - S. Guillot
- LGIT-OSUG, University of Grenoble, Grenoble, France
| | - S. Chakraborty
- Department of Chemistry, Kanchrapara College, Kanchrapara, West Bengal, India
| | - A.P. Gajurel
- Institute of Science and Technology, Tribhuvan University, Kirtipur, Kathmandu, Nepal
| | - B.N. Upreti
- Institute of Science and Technology, Tribhuvan University, Kirtipur, Kathmandu, Nepal
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15
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Van Geen A, Zheng Y, Goodbred S, Horneman A, Aziz Z, Cheng Z, Stute M, Mailloux B, Weinman B, Hoque MA, Seddique AA, Hossain MS, Chowdhury SH, Ahmed KM. Flushing history as a hydrogeological control on the regional distribution of arsenic in shallow groundwater of the Bengal Basin. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:2283-8. [PMID: 18504954 PMCID: PMC3050603 DOI: 10.1021/es702316k] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Whereas serious health consequences of widespread consumption of groundwater elevated in As have been documented in several South Asian countries, the mechanisms responsible for As mobilization in reducing aquifers remain poorly understood. We document here a previously unrecognized and consistent relationship between dissolved As concentrations in reducing groundwater and the phosphate-mobilizable As content of aquifer sediment for a set of precisely depth-matched samples from across Bangladesh. The relationship holds across nearly 3 orders of magnitude in As concentrations and suggests that regional as well as local patterns of dissolved As in shallow groundwater are set by the solid phase according to a remarkably constant ratio of approximately 250 microg/L dissolved As per 1 mg/kg P-mobilizable As. We use this relationship in a simple model of groundwater recharge to propose that the distribution of groundwater As in shallow aquifers of the Bengal Basin could primarily reflect the different flushing histories of sand formations deposited in the region over the past several thousand years.
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Affiliation(s)
- A Van Geen
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York 10964, USA.
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Near surface lithology and spatial variation of arsenic in the shallow groundwater: southeastern Bangladesh. ACTA ACUST UNITED AC 2008. [DOI: 10.1007/s00254-008-1267-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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17
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Métral J, Charlet L, Bureau S, Mallik SB, Chakraborty S, Ahmed KM, Rahman MW, Cheng Z, van Geen A. Comparison of dissolved and particulate arsenic distributions in shallow aquifers of Chakdaha, India, and Araihazar, Bangladesh. GEOCHEMICAL TRANSACTIONS 2008; 9:1. [PMID: 18190703 PMCID: PMC2246114 DOI: 10.1186/1467-4866-9-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Accepted: 01/11/2008] [Indexed: 05/18/2023]
Abstract
BACKGROUND The origin of the spatial variability of dissolved As concentrations in shallow aquifers of the Bengal Basin remains poorly understood. To address this, we compare here transects of simultaneously-collected groundwater and aquifer solids perpendicular to the banks of the Hooghly River in Chakdaha, India, and the Old Brahmaputra River in Araihazar, Bangladesh. RESULTS Variations in surface geomorphology mapped by electromagnetic conductivity indicate that permeable sandy soils are associated with underlying aquifers that are moderately reducing to a depth of 10-30 m, as indicated by acid-leachable Fe(II)/Fe ratios <0.6 in the solid phase and concentrations of dissolved sulfate >5 mg L(-1). More reducing aquifers are typically capped with finer-grained soils. The patterns suggest that vertical recharge through permeable soils is associated with a flux of oxidants on the banks of the Hooghly River and, further inland, in both Chakdaha and Araihazar. Moderately reducing conditions maintained by local recharge are generally associated with low As concentrations in Araihazar, but not systematically so in Chakdaha. Unlike Araihazar, there is also little correspondence in Chakdaha between dissolved As concentrations in groundwater and the P-extractable As content of aquifer particles, averaging 191 +/- 122 microg As/L, 1.1 +/- 1.5 mg As kg(-1) (n = 43) and 108 +/- 31 microg As/L, 3.1 +/- 6.5 mg As kg(-1) (n = 60), respectively. We tentatively attribute these differences to a combination of younger floodplain sediments, and therefore possibly more than one mechanism of As release, as well as less reducing conditions in Chakdaha compared to Araihazar. CONCLUSION Systematic dating of groundwater and sediment, combined with detailed mapping of the composition of aquifer solids and groundwater, will be needed to identify the various mechanisms underlying the complex distribution of As in aquifers of the Bengal Basin.
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Affiliation(s)
- Jerome Métral
- Environmental Geochemistry Group, LGIT-OSUG, University of Grenoble, BP 53, F-38041 Grenoble, Cedex 9, France
| | - Laurent Charlet
- Environmental Geochemistry Group, LGIT-OSUG, University of Grenoble, BP 53, F-38041 Grenoble, Cedex 9, France
| | - Sara Bureau
- Environmental Geochemistry Group, LGIT-OSUG, University of Grenoble, BP 53, F-38041 Grenoble, Cedex 9, France
| | | | | | - Kazi M Ahmed
- Department of Geology, University of Dhaka, Dhaka 1000, Bangladesh
| | - MW Rahman
- Department of Geology, University of Dhaka, Dhaka 1000, Bangladesh
| | - Zhongqi Cheng
- Lamont-doherty EarthObservatory of Columbia University, Palisades, NY 10964, USA
| | - Alexander van Geen
- Lamont-doherty EarthObservatory of Columbia University, Palisades, NY 10964, USA
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Hafeman D, Factor-Litvak P, Cheng Z, van Geen A, Ahsan H. Association between manganese exposure through drinking water and infant mortality in Bangladesh. ENVIRONMENTAL HEALTH PERSPECTIVES 2007; 115:1107-12. [PMID: 17637930 PMCID: PMC1913599 DOI: 10.1289/ehp.10051] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2007] [Accepted: 03/27/2007] [Indexed: 05/16/2023]
Abstract
BACKGROUND Manganese is a common natural contaminant of groundwater in Bangladesh. In this cross-sectional study we assessed the association between water manganese and all-cause infant mortality in the offspring of female participants in the Health Effects of Arsenic Longitudinal Study Cohort. METHODS In 2001, drinking water samples were collected, a history of well use was obtained, and a history of birth outcomes was ascertained. To avoid misclassification of exposure, women were included only if they had been drinking from the same well for most of their childbearing years (marriage years - well years = 2). Of a total of 26,002 births (among 6,537 mothers), 3,837 children were born to women with this profile. The current analysis was based on the portion of these infants (n = 3,824) with recorded exposure and outcome status, 335 of whom died before reaching 1 year of age. RESULTS Infants exposed to water manganese greater than or equal to the 2003 World Health Organization standard of 0.4 mg/L had an elevated mortality risk during the first year of life compared with unexposed infants [odds ratio (OR) = 1.8; 95% confidence interval (CI), 1.2-2.6]. Adjustment for water arsenic, indicators of social class, and other variables did not appreciably alter these results. When the population was restricted to infants born to recently married parents (marriage year 1991 or after), this elevation was more pronounced (OR = 3.4; 95% CI, 1.5-7.9). CONCLUSIONS These preliminary findings indicate a possible association between manganese exposure and infant mortality. However, given the methodologic limitations of this study, the association needs to be confirmed through future work.
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Affiliation(s)
- Danella Hafeman
- Mailman School of Public Health, Columbia University, New York, New York 10032, USA.
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Radloff KA, Cheng Z, Rahman MW, Ahmed KM, Mailloux BJ, Juhl AR, Schlosser P, Van Geen A. Mobilization of arsenic during one-year incubations of grey aquifer sands from Araihazar, Bangladesh. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2007; 41:3639-45. [PMID: 17547190 PMCID: PMC2577162 DOI: 10.1021/es062903j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Elevated As concentrations in shallow groundwater pose a major health threat in Bangladesh and similarly affected countries, yet there is little consensus on the mechanism of As release to groundwater or how it might be influenced by human activities. In this study, the rate of As release was measured directly with incubations lasting 11 months, using sediment and groundwater collected simultaneously in Bangladesh and maintained under anaerobic conditions throughout the study. Groundwater and gray sediment were collected as diluted slurries between 5 and 38 m in depth, a range over which ambient groundwater As concentrations increased from 20 to 100 microg L(-1). Arsenic was released to groundwater in slurries from 5 and 12 m in depth at a relatively constant rate of 21 +/- 4 (2 sigma) and 23 +/- 6 microg As kg(-1) yr(-1), respectively. Amendment with a modest level of acetate increased the rate of As release only at 12 m (82 +/- 18 mirog kg(-1) yr(-1)). Although the groundwater As concentration was initially highest at 38 m depth, no release of As was observed. These results indicate that the spatial distribution of dissolved As in Bangladesh and local rates of release to groundwater are not necessarily linked. Iron release during the incubations did not occur concurrently with As release, providing further confirmation thatthe two processes are not directly coupled. Small periodic additions of oxygen suppressed the release of As from sediments at all three depths, which supports the notion that anoxia is a prerequisite for accumulation of As in Bangladesh groundwater.
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Affiliation(s)
- Kathleen A Radloff
- Department of Earth and Environmental Engineering, Columbia University, New York, New York 10025, USA.
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Delineation of arsenic-contaminated zones in Bengal Delta, India: a geographic information system and fractal approach. ACTA ACUST UNITED AC 2005. [DOI: 10.1007/s00254-005-0139-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Cheng Z, van Geen A, Seddique AA, Ahmed KM. Limited temporal variability of arsenic concentrations in 20 wells monitored for 3 years in Araihazar, Bangladesh. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2005; 39:4759-66. [PMID: 16053073 DOI: 10.1021/es048065f] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Millions of people in Bangladesh have probably switched their water consumption to wells that meet the local standard for As in drinking water of 50 microg/L as a result of blanket field testing throughout the country. It is therefore important to know if As concentrations in those wells could change over time. To address this issue, we report here precise groundwater As analyses for time-series samples collected from a suite of 20 tube wells containing < or =50 microg/L As and ranging from 8 to 142 m in depth. For 17 out of 20 wells, the standard deviation of groundwater As concentrations was <10 microg/L over the 3-year monitoring period (n = 24-44 per well). Six of the 17 wells are community wells, each of which serves the needs of several hundred people in particularly affected villages. Of the three wells showing larger fluctuations in chemical composition including As, two are very shallow (8 and 10 m). Variations in As concentrations for one of these wells (50 +/- 32 microg/L, n = 36), as well as another shallow well showing smaller variations (48 +/- 5 microg/L, n = 36), appear to be coupled to seasonal precipitation and recharge linked to the monsoon. The other shallow well showing larger variations in composition indicates a worrisome and steady increase in As concentrations from 50 to 70 microg/L (n = 36) over 3 years. The time series of As (30 +/- 11 microg/L, n = 24) and other constituents in one deep community well (59 m) show large fluctuations that suggest entrainment of shallow groundwater through a broken PVC pipe. Even though the majority of wells that were initially safe remained so for 3 years, our results indicate that tube wells should be tested periodically.
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Affiliation(s)
- Z Cheng
- Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York 10964, USA.
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Graziano JH, van Geen A. Reducing arsenic exposure from drinking water: different settings call for different approaches. ENVIRONMENTAL HEALTH PERSPECTIVES 2005; 113:A360-1. [PMID: 15929873 PMCID: PMC1257611 DOI: 10.1289/ehp.113-a360] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
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