| 1. |
- Bundschuh, Jochen, et al.
(författare)
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Naturally occurring arsenic in terrestrial geothermal systems of western Anatolia, Turkey : Potential role in contamination of freshwater resources
- 2013
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 262, s. 951-959
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Tidskriftsartikel (refereegranskat)abstract
- Arsenic (As) contamination in terrestrial geothermal systems has been identified in many countries worldwide. Concentrations higher than 0.01mg/L are detrimental to human health. We examined potential consequences for As contamination of freshwater resources based on hydrogeochemical investigations of geothermal waters in deep wells and hot springs collected from western Anatolia, Turkey. We analyzed samples for major ions and trace element concentrations. Temperature of geothermal waters in deep wells showed extreme ranges (40 and 230°C), while, temperature of hot spring fluids was up to 90°C. The Piper plot illustrated two dominant water types: Na-HCO3 - type for geothermal waters in deep wells and Ca-HCO3 - type for hot spring fluids. Arsenic concentration ranged from 0.03 to 1.5mg/L. Dominance of reduced As species, i.e., As(III), was observed in our samples. The Eh value ranged between -250 and 119mV, which suggests diverse geochemical conditions. Some of the measured trace elements were found above the World Health Organization guidelines and Turkish national safe drinking water limits. The variation in pH (range: 6.4-9.3) and As in geothermal waters suggest mixing with groundwater. Mixing of geothermal waters is primarily responsible for contamination of freshwater resources and making them unsuitable for drinking or irrigation.
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| 2. |
- Bundschuh, J., et al.
(författare)
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Arsenic in Latin America : New findings on source, mobilization and mobility in human environments in 20 countries based on decadal research 2010-2020
- 2020
-
Ingår i: Critical reviews in environmental science and technology. - : Taylor and Francis Inc.. - 1064-3389 .- 1547-6537. ; , s. 1-119
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Forskningsöversikt (refereegranskat)abstract
- Today (year 2020), the globally recognized problem of arsenic (As) contamination of water resources and other environments at toxic levels has been reported in all of the 20 Latin American countries. The present review indicates that As is prevalent in 200 areas across these countries. Arsenic is naturally released into the environment and mobilized from geogenic sources comprising: (i) volcanic rocks and emissions, the latter being transported over thousands of kilometers from the source, (ii) metallic mineral deposits, which get exposed to human beings and livestock through drinking water or food chain, and (iii) As-rich geothermal fluids ascending from deep geothermal reservoirs contaminate freshwater sources. The challenge for mitigation is increased manifold by mining and related activities, as As from mining sites is transported by rivers over long distances and even reaches and contaminates coastal environments. The recognition of the As problem by the authorities in several countries has led to various actions for remediation, but there is a lack of long-term strategies for such interventions. Often only total As concentration is reported, while data on As sources, mobilization, speciation, mobility and pathways are lacking which is imperative for assessing quality of any water source, i.e. public and private.
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| 3. |
- Irunde, R., et al.
(författare)
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Developing innovations for adsorptive removal of arsenic from drinking water sources in north mara gold mining area, Tanzania
- 2016
-
Ingår i: Arsenic Research and Global Sustainability - Proceedings of the 6th International Congress on Arsenic in the Environment, AS 2016. - : CRC Press/Balkema. - 9781138029415 ; , s. 559-560
-
Konferensbidrag (refereegranskat)abstract
- Arsenic (As) contamination in drinking water have been reported to occur in areas where mining are practiced such as North Mara, lake Victoria basin in Mwanza, Geita and Rukwa. The removal of As requires methods such as ion-exchange, reverse osmosis, electrodialysis, contact precipitation, acti-vated alumina, bone charcoal and activated clay. The use of ion-exchange, reverse osmosis and electrodi-alysis are expensive to be implemented in Tanzania. In order to safeguard the drinking water supplies, it is important to explore the low-cost and efficient locally available adsorbents such as activated alumina, bone char and clay for the removal of As for drinking water consumption.
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| 4. |
- Ligate, F. J., et al.
(författare)
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Occurrence of arsenic in groundwater, soil and sediments in Tanzania
- 2016
-
Ingår i: Arsenic Research and Global Sustainability - Proceedings of the 6th International Congress on Arsenic in the Environment, AS 2016. - : CRC Press/Balkema. - 9781138029415 ; , s. 88-89
-
Konferensbidrag (refereegranskat)abstract
- Tanzania is among the sub-Sahara African countries where most of the rural populations use ground water for drinking and other household activities. The presence of elevated concentrations of arsenic in some parts of Tanzania is possibly related to both geogenic and anthropogenic sources. From its origin in the bed-rock, inorganic As enters into soil where its concentration depends on the parent rock, climate, forms of As, redox conditions of the soils as well as anthropogenic activities. The interactions of water with rocks and sediments together with environmental deposition have resulted into high concentration in groundwater. Microbial activities in soil and sediments may produce the methylated form of As which are volatile in nature and can re-enter the atmosphere and ultimately be re converted back to inorganic forms. Exposure to elevated concentration of arsenic causes arsenicosis. Further investigations are needed in order to come up with a comprehensive report concerning the occurrence and distribution of As in Tanzania.
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| 5. |
- Bhattacharya, Prosun, et al.
(författare)
-
Distribution and mobility of arsenic in the Rio Dulce alluvial aquifers in Santiago del Estero Province, Argentina
- 2006
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 358:1-3, s. 97-120
-
Tidskriftsartikel (refereegranskat)abstract
- Factors controlling arsenic (As) mobilization in the aquifers of the Rio Dulce alluvial cone were investigated. Groundwater analyses show severe As contamination (average concentration of 743 mu g/L) from geogenic sources, but spatial variability of As concentration is considerable. Sequential leaching of sediment samples from unsaturated zone using de-ionised water, bicarbonate, acetate, and oxalate extracted As to different extents. Sediment oxalate extraction showed that Al and Mn oxide and hydroxides are more abundant than Fe oxides and hydroxides, in spite of similar total Fe, Mn, and Al concentrations in the sediment. Speciation calculations performed for saturated zone samples indicated that Fe and Al oxides and hydroxides are stable in groundwater, suggesting that As adsorption processes may be to some extent controlled by the presence of Fe and Al mineral phases. Principal Component Analysis (PCA) showed that As is related to F, V, Mo, B, Si, most likely due to their common origin in volcanic ash. This suggests the volcanic ash as the probable source of groundwater As. Locally, elevated pH values linked to carbonate dissolution, cation exchange, and dissolution of silicates promote release of adsorbed As. Another factor contributing to the release of As locally may be the input of organic matter from excessive irrigation. The conceptual model of As release includes: i) As influx from dissolution of volcanic glass in volcanic ash, ii) adsorption of As on the surface of Fe and Al mineral phases in relatively low pH zones, and iii) high mobility of As in high pH zones. Future work should be focused on the determination of mineralogical forms of As in volcanic ash and on detailed investigation on factors controlling As mobility.
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| 6. |
- Bhowmick, S., et al.
(författare)
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Arsenic mobilization in the aquifers of three physiographic settings of West Bengal, India : Understanding geogenic and anthropogenic influences
- 2013
-
Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 262, s. 915-923
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Tidskriftsartikel (refereegranskat)abstract
- A comparative hydrogeochemical study was carried out in West Bengal, India covering three physiographic regions, Debagram and Chakdaha located in the Bhagirathi-Hooghly alluvial plain and Baruipur in the delta front, to demonstrate the control of geogenic and anthropogenic influences on groundwater arsenic (As) mobilization. Groundwater samples (n=90) from tube wells were analyzed for different physico-chemical parameters. The low redox potential (Eh=-185 to -86mV) and dominant As(III) and Fe(II) concentrations are indicative of anoxic nature of the aquifer. The shallow (<100m) and deeper (>100m) aquifers of Bhagirathi-Hooghly alluvial plains as well as shallow aquifers of delta front are characterized by Ca2+HCO3 - type water, whereas Na+ and Cl- enrichment is found in the deeper aquifer of delta front. The equilibrium of groundwater with respect to carbonate minerals and their precipitation/dissolution seems to be controlling the overall groundwater chemistry. The low SO4 2- and high DOC, PO4 3- and HCO3 - concentrations in groundwater signify ongoing microbial mediated redox processes favoring As mobilization in the aquifer. The As release is influenced by both geogenic (i.e. geomorphology) and anthropogenic (i.e. unsewered sanitation) processes. Multiple geochemical processes, e.g., Fe-oxyhydroxides reduction and carbonate dissolution, are responsible for high As occurrence in groundwaters.
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| 7. |
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| 8. |
- Bundschuh, J., et al.
(författare)
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Groundwater arsenic in the Chaco-Pampean Plain, Argentina : Case study from Robles County, Santiago del Estero Province
- 2004
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Ingår i: Applied Geochemistry. - : Elsevier BV. - 0883-2927 .- 1872-9134. ; 19:2, s. 231-243
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Tidskriftsartikel (refereegranskat)abstract
- In large parts of rural Argentina people depend on groundwater whose As content exceeds the Argentine drinking water standards (0.05 mg l(-1)). The most affected areas are located in the Chaco-Pampean Plain, where aquifers comprise Tertiary loess deposits (in the Pampean Plain) and Tertiary and Quaternary fluvial and aeolian sediments (in the Chaco Plain). Robles county is located in the alluvial cone of the Dulce River consisting of loess (aeolian), and gravel, silt, sand and clay (alluvial) deposits. In the shallow aquifers, more than 48% of the 63 studied wells show As at toxic levels (maximum 4.8 mg l(-1)), while in the deep groundwater the concentration is below 0.05 mg l(-1). The pH of the shallow groundwaters range between 6.5 and 9 and generally have high electrical conductivity with mean values of 2072 and 1693 muS/cm(-1) in the years 1998 and 1999, respectively. Arsenic concentrations are high in the alkaline Na-HCO3 type groundwaters, where As correlates positively with Na+ and HCO3-. Moreover, As correlates positively with Mo, U, and V, while a negative correlation was observed with Ca2+ and Mg2+. The potential sources of groundwater As are: (i) layers of volcanic ash with 90% of rhyolitic glass; (ii) volcanic glass dispersed in the sediments; and (iii) clastic sediments of metamorphic and igneous origin. Great lateral variability in the concentration of groundwater As is caused by several hydrogeological and hydrogeochemical factors.
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| 9. |
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| 10. |
- Ijumulana, J., et al.
(författare)
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Arsenic occurrence in groundwater sources of Lake Victoria basin in Tanzania
- 2016
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Ingår i: Arsenic Research and Global Sustainability - Proceedings of the 6th International Congress on Arsenic in the Environment, AS 2016. - : CRC Press/Balkema. - 9781138029415 ; , s. 86-87
-
Konferensbidrag (refereegranskat)abstract
- Increasing naturally occurring toxic substances are becoming threat to many safer groundwater sources worldwide. Their detection, scale of occurrence and removal procedures requires sophisticated tools. This study employs geostatistical methods to study the extent of arsenic occurrence over Lake Victoria basin in Tanzania. Water samples are randomly taken at village level from available drinking water source, tested at water quality laboratory to quantify levels of As concentrations. The study further uses fuzzy logics to identify areas with no, low, moderate and high As concentrations based on the World Health Organization (WHO) guidelines and Tanzania Bureau of Standards (TBS) standards of 0.01 mg/L and 0.05 mg/L As respectively. The result of this study is vital to understanding severity of As contamination and prediction of potential human health effects dwelling within these regions.
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| 11. |
- Jean, J. -S, et al.
(författare)
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The Taiwan crisis : A showcase of the global arsenic problem
- 2010
-
Bok (övrigt vetenskapligt/konstnärligt)abstract
- In the 1950s, the residents of the southwestern coastal areas of Taiwan suffered greatly from Blackfoot disease (BFD) due to the consumption of arsenic-contaminated groundwater. Groundwater with high levels of arsenic in southwestern and northeastern Taiwan received much attention. After arsenic-safe tap water was utilized for drinking instead of groundwater in the 1970s, BFD cases decreased greatly. After 1990, no new BFD cases were reported, and as a consequence, BFD problems disregarded. However, arsenic is still present in the groundwater.This book will improve the knowledge and understanding of the occurrence and genesis of arsenic-rich groundwaters in Taiwan. It deals with constraints on the mobility of arsenic in groundwater, its uptake from soil and water by plants, arsenic-propagation through the food chain, human health impacts, and arsenic-removal technologies. Taiwan case experiences are described in this book and can be applied worldwide. This book is a state-of-the-art overview of research on arsenic in Taiwan and is designed to: • create interest in regions within Taiwan that are affected by the presence of arseniferous aquifers; • draw attention from the international scientific community; • increase awareness among researchers, administrators, policy makers, and company executives; • improve the international cooperation on arsenic problems worldwide.
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| 12. |
- Maity, J. P., et al.
(författare)
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Advanced application of nano-technological and biological processes as well as mitigation options for arsenic removal
- 2021
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 405
-
Tidskriftsartikel (refereegranskat)abstract
- Arsenic (As) removal is a huge challenge, since several million people are potentially exposed (>10 μg/L World Health Organization guideline limit) through As contaminated drinking water worldwide. Review attempts to address the present situation of As removal, considering key topics on nano-technological and biological process and current progress and future perspectives of possible mitigation options have been evaluated. Different physical, chemical and biological methods are available to remove As from contaminated water/soil/wastes, where removal efficiency mainly depends on absorbent type, initial adsorbate concentration, speciation and interfering species. Oxidation is an important pretreatment step in As removal, which is generally achieved by several media such as O2/O3, HClO, KMnO4 and H2O2. The Fe-based-nanomaterials (α/β/γ-FeOOH, Fe2O3/Fe3O4–γ-Fe2O3), Fe-based-composite-compounds, activated-Al2O3, HFO, Fe-Al2O3, Fe2O3-impregnated-graphene-aerogel, iron-doped-TiO2, aerogel-based- CeTiO2, and iron-oxide-coated-manganese are effective to remove As from contaminated water. Biological processes (phytoremediation/microbiological) are effective and ecofriendly for As removal from water and/or soil environment. Microorganisms remove As from water, sediments and soil by metabolism, detoxification, oxidation-reduction, bio-adsorption, bio-precipitation, and volatilization processes. Ecofriendly As mitigation options can be achieved by utilizing an alternative As-safe-aquifer, surface-water or rainwater-harvesting. Application of hybrid (biological with chemical and physical process) and Best-Available-Technologies (BAT) can be the most effective As removal strategy to remediate As contaminated environments.
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| 13. |
- Maity, J. P., et al.
(författare)
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Hydrogeochemical reconnaissance of arsenic cycling and possible environmental risk in hydrothermal systems of Taiwan
- 2017
-
Ingår i: Groundwater for Sustainable Development. - : Elsevier. - 2352-801X. ; 5, s. 1-13
-
Tidskriftsartikel (refereegranskat)abstract
- Hydrothermal activity creates geo-hydro-chemical interactions between hot water/fluid and the host rocks, which changes the hydro-chemical composition of the geothermal water/fluid and enriches trace elements. Existence of arsenic (As) is reported from different hydrothermal systems as well as several region in groundwater system at elevated concentration globally, compared to 10 μg/L WHO (World health Organization) guideline. The distribution of dissolved major and minor elements, including arsenic (As) was studied in hydrothermal systems of Taiwan. For the first time in Taiwan As(V) and As(III) species were researched from the three principal geological settings of Taiwan. Aim was to understand the cycling, fate and transport and potential impact of As on the surficial hydrological systems. Water samples were collected from sixteen hydrothermal springs of 3 different geological settings. Three groups of hydrothermal spring water samples could be distinguished: (i) strongly acidic (pH<3), sulfate-enriched waters of H-SO4-type (Yangmingshan, and Taipu, Beitou), (ii) slightly alkaline waters (pH: 8–8.95) (Jiben, Antung and Kung-Tzu-Ling), and (iii) circum-neutral waters (pH 6.47–7.41) of Na-HCO3/Na-Cl-HCO3-type (Wulai, Hongye, Rueisuei, Chung-Lun and Biolai). The waters are enriched with alkali and alkali earth metals compared to drinking water. Similarly, the water of most of the geothermal springs were found to be enriched with As (highest concentration at Beitou: 1.456 mg/L) with As(III) being the principal As species. Arsenic concentrations of hydrothermal spring waters in igneous rock terrains exhibit highest concentrations (0.69±0.71 mg/L) followed by those of sedimentary (0.16±0.14 mg/L) and metamorphic (0.06±0.02 mg/L) terrains. The discharged geothermal springs water contaminate the surface and groundwater (including drinking and irrigation water resources), where significant levels of arsenic and other toxic element have detected and hence being a significant risk for human health and environmental.
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| 14. |
- Maity, J. P., et al.
(författare)
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Investigation of arsenic contamination from geothermal water in different geological settings of Taiwan : Hydrogeochemical and microbial signatures
- 2016
-
Ingår i: Arsenic Research and Global Sustainability - Proceedings of the 6th International Congress on Arsenic in the Environment, AS 2016. - : CRC Press/Balkema. - 9781138029415 ; , s. 84-85
-
Konferensbidrag (refereegranskat)abstract
- The dissemination of dissolved elements, including arsenic (As(V)/As(III)) and microbial diversity was studied in hydrothermal systems of Taiwan considering three different principal geological settings such as Igneous rock terrains, Metamorphic terrains and Sedimentary terrains to understand the cycling, fate and transport and potential impact of As on hydrological systems. The results were indicated as strongly acidic (pH< 3), sulfate-enriched waters of H-SO4-type in igneous-sedimentary rock terrains, slightly alkaline waters (pH: 8–8.95) in metamorphic terrains, and circum-neutral waters (pH 6.47–7.41) of Na-HCO3/Na-Cl-HCO3-type in metamorphic-sedimentary terrains. The geothermal waters were enriched with As in igneous terrains (Beitou: 1.46 mg/L) as compared to sedimentary (0.16 ± 0.14 mg/L) or metamorphic (0.06 ± 0.02 mg/L) terrains. The 16S rRNA gene sequence of bacterial diversity indicates prevalence of mesophilic sulfur- and thiosulfate-oxidizing bacterium in Taipu (igneous rock terrains). The discharge from geothermal springs with significant levels of As and other toxic element contaminate the surface and groundwater of environment.
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| 15. |
- Maity, J. P., et al.
(författare)
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Removal of fluoride from water through bacterial-surfactin mediated novel hydroxyapatite nanoparticle and its efficiency assessment : Adsorption isotherm, adsorption kinetic and adsorption Thermodynamics
- 2018
-
Ingår i: Environmental Nanotechnology, Monitoring and Management. - : Elsevier. - 2215-1532. ; 9, s. 18-28
-
Tidskriftsartikel (refereegranskat)abstract
- Fluoride contamination in water due to natural and anthropogenic activities has been documented as serious problems worldwide commanding a major threat to the environment. Present study focuses to synthesis bacterial-surfactin (Bacillus subtilis) mediated nano-hydroxyapatite (HAp), novel adsorbents for defluoridation. HAp particle size and morphology were controlled by varying temperature of 90–150 °C and pH of 7–11, respectively. The TEM and SEM micrographs reveal that the short-rod particle is observed 20–30 nm at 90 °C and pH 11. The ratio between the length (nm) and width (nm) of nanoparticle are decreased from 4.17 to 1.65 with increasing pH (7–11). The selected area diffraction (SAD) of particles are indicated uniform rod-like monocrystals. The XRD and FTIR observations were indicated the synthesized HAp nanoparticles were well-crystallized with purity phase and high quality. The study reflected that the fluoride removal from contaminated water by HAp was increased significantly (R2 = 99) with the increasing adsorbent concentration, temperature and time, with two-step adsorption process as the first portion a rapid adsorption occurs during first 90 min after which equilibrium is slowly achieved. The adsorption process is closer to Freundlich isotherm (R2 > 98) than to Langmuir isotherm (R2 ≈ 92), indicating HAp as a good adsorbent (n > 3). Above 97% of fluoride removal were noticed at a HAp dose of 0.06 g/10 mL. The adsorption kinetics more fit with pseudo-second-order (R2= 99) in compare to pseudo-first-order (R2 ≈ 91). The slope and intercept of Arrhenius equation indicated the activation/adsorption energy (Ea) of 3.199 kJ/mol and frequency factor (A) of 1.78 1/s. Adsorption thermodynamic parameters (free energy (ΔG < 0), enthalpy (ΔH > 0) and entropy (ΔS > 0)) indicates the spontaneous and endothermic reactions of the adsorption process. Thus, newly synthesized HAp nanoparticles exhibit as a good adsorbent for fluoride removal, theoretically and experimentally being applicable for environmental pollution control.
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| 16. |
- Nriagu, J. O., et al.
(författare)
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Arsenic in soil and groundwater : an overview
- 2007. - 9
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Ingår i: Arsenic in Soil and Groundwater Environment. - Amsterdam, The Netherlands : Elsevier. - 9780444518200 ; , s. 3-60
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Contamination of the environment with arsenic (As) from both anthropogenic and natural sources has occurred in many parts of the world and is recognized as a global problem. Principal anthropogenic sources of As include base metal smelters, gold mines, power plants that burn As-rich coals or treated lumber, disposal sites for wastes from As-processing plants, as well as industrial and municipal dump sites. In many areas, the levels of As in the environment have become one of concern and epidemiological studies have documented various adverse health effects on local populations. Arsenic poisoning episodes from exposure to industrial sources have been reported all over the world; for instance, in Japan, where cases have been associated with pollution around As mines and pollution of groundwater around As-using industries and industrial waste burial sites. Other examples of contaminated environments with increased risk for As poisoning include agricultural lands treated with arsenical pesticides, urban areas, war zones defoliated or sprayed with As compounds, and the superfund sites in the United States and other countries. Although a lot of people get exposed, most often, however, it is not possible to associate the exposure to elevated As levels with adverse human health effects. Nevertheless, long-term cumulative exposure to As in these contaminated environments should be a matter of public health concern and scientific interest.
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| 17. |
-
Arsenic Research and Global Sustainability: Proceedings of the Sixth International Congress on Arsenic in the Environment (As2016), June 19-23, 2016, Stockholm, Sweden
- 2016
-
Proceedings (redaktörskap) (refereegranskat)abstract
- The Congress "Arsenic in the Environment" offers an international, multi- and interdisciplinary discussion platform for research and innovation aimed towards a holistic solution to the problem posed by the environmental toxin arsenic, with considerable societal impact. The congress has focused on cutting edge and breakthrough research in physical, chemical, toxicological, medical, agricultural and other specific issues on arsenic across a broader environmental realm. The Congress "Arsenic in the Environment" was first organized in Mexico City (As2006) followed by As2008 in Valencia, Spain, As2010 in Tainan, Taiwan, As2012 in Cairns, Australia and As2014 in Buenos Aires, Argentina. The 6th International Congress As2016 was held June 19-23, 2016 in Stockholm, Sweden and was entitled Arsenic Research and Global Sustainability.
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| 18. |
- Bhattacharya, Prosun, et al.
(författare)
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Arsenic in the environment : Biology and Chemistry
- 2007
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 379:03-feb, s. 109-120
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Forskningsöversikt (refereegranskat)abstract
- Arsenic (As) distribution and toxicology in the environment is a serious issue, with millions of individuals worldwide being affected by As toxicosis. Sources of As contamination are both natural and anthropogenic and the scale of contamination ranges from local to regional. There are many areas of research that are being actively pursued to address the As contamination problem. These include new methods of screening for As in the field, determining the epidemiology of As in humans, and identifying the risk of As uptake in agriculture. Remediation of As-affected water supplies is important and research includes assessing natural remediation potential as well as phytoremediation. Another area of active research is on the microbially mediated biogeochemical interactions of As in the environment. In 2005, a conference was convened to bring together scientists involved in many of the different areas of As research. In this paper, we present a synthesis of the As issues in the light of long-standing research and with regards to the new findings presented at this conference. This contribution provides a backdrop to the issues raised at the conference together with an overview of contemporary and historical issues of As contamination and health impacts. Crown
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| 19. |
- Bhattacharya, Prosun, et al.
(författare)
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Groundwater characteristics in the shallow aquifers of Huhhot region in Inner Mongolia, PR China : Implications on the mobilisation of arsenic
- 2006
-
Ingår i: Natural Arsenic in Groundwaters of Latin America. ; , s. 11-12
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Elevated arsenic (As) concentration ingroundwater is becoming a worldwide problem. In Huhhot Alluvial Basin (HAB) in Inner Mongolia, People’s Republic ofChina, a population of over a million isexposed to severe health risk due to theconsumption of groundwater with high Asconcentration. In some arsenic seriouslyaffected areas, As concentration reach 1491µg L-1, 149 times over WHO’s drinkingwater guideline value for As and exceed theChinese drinking water standard by a factorof 30 times. Due to the acute shortage ofsafe water supply and inefficient watermanagement system, people are compelledto drink groundwater with high As concentration. Long period ingestion of water withhigh As concentration have lead to chronicarsenic poisoning among the residents ofthe region. This present work deals with thehydrogeochemical characterisation of thegroundwater of the shallow alluvial aquifers and their implications on the chemistryand its relation to the mechanism of Asmobilization in the HAB.Groundwater samples were collected during October 2003, from 29 sites in the village of Tie Men Jing, located about 100 kmfrom Inner Mongolia’s capital Huhhot. ThepH, redox potential (Eh), temperature andelectrical conductivity were measured atsites while major ions, trace elements including As total and As (III) were analyzedin laboratories at the Royal Institute ofTechnology and Stockholm University inSweden. Groundwater is generally neutralto alkaline and the pH varies from 6.67 to8.7. The redox potential (Eh) lies between74 and 669 mV. The electrical conductivity(EC) range varies from 581 to 5200 µS cm-1. Temperature ranges from 9.1 to 13.5 °C.Depths of wells are from 4 m to 75 m.Groundwater is mostly of Na-Mg-HCO3-Cl-type and dominated by HCO3-and Cl-asthe predominant anions. The concentrationsof SO42-range between 0.3 and 172.8 mg L-1and there is a trend of decreasing sulfateconcentrations with increase in well depth.The levels of NO3-were lower than theWHO´s guideline value of 50 mg L-1in 27wells. These high NO3-concentrations could have been caused by anthropogeniccontamination due to the sanitation practices.The PO43-concentration ranges between 0.04to 2.6 mg L-1.Total As concentration ranged from belowdetect limit (5.2 µg L-1) to 141 µg L-1. In 28of the investigated wells, As levels exceededWHO’s guideline value 10 µg L-1and 17wells exceeded Chinese standard 50 µg L-1.Among the 42 groundwater samples of theshallow aquifers only three complied withthe WHO drinking water guideline value forAs. The dominant species in the groundwaterwas As (III). In the 29 wells of Tie MenJing, the concentration of Fe and Mn –exceeded the WHO’s guideline value by afactor of 10.The aquifers are composed of Quaternary(mainly Holocene) fluvial and lacustrinesediments. High As occurring in anaerobicgroundwater in low-lying areas is associatedwith high concenrations of dissolved Fe andMn. Improved water supply system, employment new water and energy resources,poverty fighting and expertise cooperationare recommended to solve Huhhot basinrural area’s drinking water problem.
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| 20. |
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| 21. |
- Bundschuh, Jochen, et al.
(författare)
-
Editor's preface
- 2017
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Ingår i: Geothermal, Wind and Solar Energy Applications in Agriculture and Aquaculture. - : Informa UK Limited. ; , s. xxxix-xl
-
Bokkapitel (refereegranskat)
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| 22. |
- Bundschuh, Jochen, et al.
(författare)
-
Geothermal, wind and solar energy applications in agriculture and aquaculture
- 2017
-
Bok (övrigt vetenskapligt/konstnärligt)abstract
- The agri-food chain consumes about one third of the world's energy production with about 12% of it for crop production and nearly 80% for processing, distribution, retail, preparation and cooking. The agri-food chain also accounts for 80-90% of total global freshwater use where 70% alone is for irrigation. Additionally, on a global scale, freshwater production consumes nearly 15% of the entire energy production. It can therefore be argued that making agriculture and the agri-food supply chain independent from fossil fuel use has a huge potential to contribute to global food security and climate protection not only for the next decades but also for the coming century. Provision of secure, accessible and environmentally sustainable supplies of water, energy and food must thus be a priority. One of the major objectives of the world's scientists, farmers, decisions makers and industrialists is to overcome the present dependence on fossil fuels in the agro-food sector. This dependency increases the volatility of food prices and affects economic access to sustenance. This book provides a critical review of recent developments in solar, wind and geothermal energy applications in agriculture and the agro-food sector such as processing, distribution, retail, preparation and cooking.
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| 23. |
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| 24. |
- Chen, C. -Y, et al.
(författare)
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Occurrence of arsenic and related microbial signature of hydrothermal systems in Western Turkey
- 2012
-
Ingår i: Understanding the Geological and Medical Interface of Arsenic, As 2012 - 4th International Congress: Arsenic in the Environment. - : CRC Press. - 9780415637633 ; , s. 486-488
-
Konferensbidrag (refereegranskat)abstract
- The naturally occurring aqueous Arsenic (As) and other toxic elements are found around the world. The present study concentrates on arsenic concentrations, speciation and related microbial diversity in a hydrothermal system in Western Turkey. The surface temperatures of hot springs reach up to 90°C and deep well (reservoir) temperatures vary in the range of 40 to 230°C. The elements such as As, B, Br, Ba, Cr, Fe, Mn, V and Zn are found in high concentration in hydrothermal waters. Hydrogeochemically, Seferihisar hot spring exhibited a Na-Cl water type. On the other hand, Karahayit, Pamukkale, Emirfaki, Alaşehir and Sart exhibit a Ca-HCO 3 water type and Çitgöl exhibited a Na-HCO 3-SO 4 water type. The arsenic (As) concentrations in geothermal waters of Western Anatolia have been detected to range from 0.03 mg/L to 1.5 mg/L, including Buharkent (İnalti) (1.50 ± 0.005 mg/L), Kizildere (1.13 ± 0.005 mg/L), Eynal (0.71 ± 0.005 mg/L) and Sarayköy (0.06 ± 0.004 mg/L). Arsenic (III) is the dominant species in geothermal water of Western Anatolia. The 16S rRNA gene sequences of bacterial diversity show that the thermophilic, sulfur/thiosulfate-oxidizing bacterium (Thiobacter subterraneus) is present in Kula geothermal water and mesophilic sulfur- and thiosulfate-oxidizing Sulfurovum lithotrophicum bacterium occurs in Sarayköy geothermal spring. Also, Bacillus fumarioli, (a thermophilic, aerobic endospore forming bacterium growing on (NH 4) 2 SO 4, MgSO 4 and MnSO 4 at 50-55°C), Schlegelella thermodepolymerans and Methylocaldum szegediense are rich in geothermal water.
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| 25. |
- Herath, I., et al.
(författare)
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Geochemical processes for mobilization of arsenic in groundwater
- 2016
-
Ingår i: Arsenic Research and Global Sustainability - Proceedings of the 6th International Congress on Arsenic in the Environment, AS 2016. - : CRC Press/Balkema. - 9781138029415 ; , s. 23-24
-
Konferensbidrag (refereegranskat)abstract
- This paper presents an overview of natural geochemical processes that can mobilize arsenic (As) from aquifer sediments into groundwater. The primary source of As in groundwater is pre-dominantly natural (geogenic), and can be mobilized via complicated biogeochemical interactions within various aquifer solids and water. Oxidation of sulfide minerals such as arsenopyrite, As-substituted pyrite and other sulfide minerals are susceptible to oxidation in near surface environment, and release significant quantities of As from sediments. Reductive dissolution of As-bearing Fe(III) oxides/hydroxides 2and sulfide oxidation are the most common and significant geochemical triggers that tend to release As from aquifer sediments into groundwater. Hence, strengthening direct action and implementation of the best practices to target the safe groundwater sources for installing safe drinking water wells are an urgent necessity for sustainable As mitigation on a global scale.
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| 26. |
- Herath, I., et al.
(författare)
-
Sulfur-arsenic interactions and formation of thioarsenic complexes in the environment
- 2018
-
Ingår i: Environmental Arsenic in a ChangingWorld - 7th International Congress and Exhibition Arsenic in the Environment, 2018. - London : CRC Press/Balkema. - 9781138486096 ; , s. 210-211
-
Konferensbidrag (refereegranskat)abstract
- Thiolated arsenic compounds are the sulfur analogous substructures of oxo-arsenicals as the arsinoyl (As=O) is substituted by an arsinothioyl (As=S) group. Relatively brief history of thioarsenic research, mostly in the current decade has endeavored to understand their consequences in the natural environment. However, thioarsenic related aspects have by far not attached much research concern on global scale compared to other arsenic species. This paper provides a critical overview on formation mechanisms of thioarsenicals and their chemistry aiming to direct future research towards thioasenic mitigation strategies. Sulfur-arsenite/arsenate interactions and dissolution of arsenic sulfide minerals are the main mechanisms that involve in the formation of different thioarsenic species in the natural environment. The formation and chemical analysis of thioarsenicals in soil and sediments are highly unknown. Future research needs to be more inclined towards in determining the molecular structure of unknown thioarsenic complexes in various environmental suites.
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| 27. |
- Hoinkis, J., et al.
(författare)
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Arsenic removal by small-scale reverse osmosis units
- 2010
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Ingår i: The Global Arsenic Problem: Challenges for Safe Water Production. - : CRC Press. ; , s. 147-156
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Over the past three decades, the occurrence of high concentrations of arsenic (As) in drinking water has been recognized as a severe global public-health concern (Bhattacharya et al. 2002, Mandal and Suzuki 2002, Ng et al. 2003). The global As-contamination scenario has changed considerably in recent years, with the discovery of new As affected sites. The delayed health effects of exposure to As, the lack of common definitions and of local awareness, as well as poor reporting in affected areas are all major problems in determining the extent of the arsenic-in-drinking-water problem (WHO 2008).
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| 28. |
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| 29. |
- Ilbeigi, Kayhan, et al.
(författare)
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Assessing Environmental Risks during the Drug Development Process for Parasitic Vector-Borne Diseases : A Critical Reflection
- 2024
-
Ingår i: ACS - Infectious Diseases. - 2373-8227.
-
Forskningsöversikt (refereegranskat)abstract
- Parasitic vector-borne diseases (VBDs) represent nearly 20% of the global burden of infectious diseases. Moreover, the spread of VBDs is enhanced by global travel, urbanization, and climate change. Treatment of VBDs faces challenges due to limitations of existing drugs, as the potential for side effects in nontarget species raises significant environmental concerns. Consequently, considering environmental risks early in drug development processes is critically important. Here, we examine the environmental risk assessment process for veterinary medicinal products in the European Union and identify major gaps in the ecotoxicity data of these drugs. By highlighting the scarcity of ecotoxicological data for commonly used antiparasitic drugs, we stress the urgent need for considering the One Health concept. We advocate for employing predictive tools and nonanimal methodologies such as New Approach Methodologies at early stages of antiparasitic drug research and development. Furthermore, adopting progressive approaches to mitigate ecological risks requires the integration of nonstandard tests that account for real-world complexities and use environmentally relevant exposure scenarios. Such a strategy is vital for a sustainable drug development process as it adheres to the principles of One Health, ultimately contributing to a healthier and more sustainable world.
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| 30. |
- Islam, A. B. M. R., et al.
(författare)
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Arsenic mineral dissolution and possible mobilization in mineral-microbe-groundwater environment
- 2013
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 262, s. 989-996
-
Tidskriftsartikel (refereegranskat)abstract
- Arsenic (As) is widely distributed in the nature as ores or minerals. It has been attracted much attention for the global public health issue, especially for groundwater As contamination. The aim of this study was to elucidate the characteristics of microbes in groundwater where As-minerals were dissolved. An ex situ experiment was conducted with 7 standard As-minerals in bacteria-free groundwater and stored in experimental vessels for 1 year without supplementary nutrients. The pH (6.7-8.4) and EhS.H.E. (24-548mV) changed between initial (0 day) and final stages (365 days) of experiment. The dissolution of As was detected higher from arsenolite (4240±8.69mg/L) and native arsenic (4538±9.02mg/L), whereas moderately dissolved from orpiment (653±3.56mg/L) and realgar (319±2.56mg/L) in compare to arsenopyrite (85±1.25mg/L) and tennantite (3±0.06mg/L). Optical microscopic, scanning electron microscopic observations and flurometric enumeration revealed the abundance of As-resistant bacillus, coccus and filamentous types of microorganisms on the surface of most of As-mineral. 4'-6-Diamidino-2-phenylindole (DAPI)-stained epifluorescence micrograph confirmed the presence of DNA and carboxyfluorescein diacetate (CFDA) staining method revealed the enzymatically active bacteria on the surface of As-minerals such as in realgar (As4S4). Therefore, the microbes enable to survive and mobilize the As in groundwater by dissolution/bioweathering of As-minerals.
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| 31. |
- Khan, E. U., et al.
(författare)
-
Biogas energy polygeneration integrated with air-gap membrane distillation (AGMD) as arsenic mitigation option in rural Bangladesh
- 2016
-
Ingår i: Arsenic Research and Global Sustainability - Proceedings of the 6th International Congress on Arsenic in the Environment, AS 2016. - : CRC Press/Balkema. - 9781138029415 ; , s. 554-556
-
Konferensbidrag (refereegranskat)abstract
- Sustainable energy and drinking water access have been seen as major challenges for rural households in Bangladesh despite of governmental and non-governmental organizations have been made extensive efforts. This study contemplates a universal approach towards tackling both of these issues via biogas based polygeneration integrated with membrane distillation employed at the village level. The specific technologies chosen for the key energy conversion steps are as follows: plug-flow digester (co-digestion and mesophilic condition); internal combustion engine; and air-gap membrane distillation. The proposed techno-economic results show that daily electricity demand can be met with such a system while simultaneously providing 0.4 m3cooking fuel and 2–3 L pure drinking water. Cost analysis illustrates that the approach is highly favorable compare to other available system. The payback time of such system is between 2 and 2.5 years.
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| 32. |
- Mckie, Brendan, et al.
(författare)
-
Evaluating the properties, fate and individual-to-ecosystem level impacts of contrasting microplastics in freshwaters
- 2023
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Microplastic particles (MPs) are fragments, fibres and other shapes derived fromplastic polymers in the size range of 1–5 000 μm. Concern about the environmentalimpacts of MPs and their implications for human wellbeing has never been higher.Unfortunately, growth in the empirical understanding of the dynamics and impactsof MPs lags behind. This hinders the capacity of scientists, managers and policymakers to address public concerns about the true level of risk posed by MPs, andto develop effective management, policy and governance strategies for eliminatingor reducing those risks.Research on the behaviour and impacts of MPs in freshwater ecosystems is especiallydeficient, despite their vulnerability to inputs of plastic waste (e.g. via storm waterand other terrestrial runoff), and their capacity to act as key transport pathwaysthrough the landscape. This represents a substantial black box in our understandingof the dynamics of MPs from inland to the ocean.In seven research activities (5 mesocosm experiments, 1 field study and 1 literaturereview) we addressed two broad research questions:a) Initial fate and environmental interactions of MP particles in streams, includingbiofilm formation and sorption of chemical stressorsb) Ecological impacts of MPs on resource consumption, growth and survival oforganisms, and on key ecosystem processes.Among our key results addressing the initial fate and biofilm formation of MPparticles, we found that (i) biofilm formation generally made denser particles morebuoyant and caused more buoyant particles to sink faster, (ii) biofilms on polystyreneMPs supported more cyanobacteria than other polymers, and (iii) aquatic macrophytesincrease MP retention by up to 94 %.Among our key results addressing the ecological impacts of MPs, we found that almostall MP shapes and polymers studied had one or more effects on stream microbialorganisms and associated ecosystem processes (e.g. microbial respiration, detritusbreakdown), and/or on the life history of a model macroinvertebrate detritivore.We also provide evidence that effects of MPs on microbial organisms can propagateup food-chains to affect consumer growth and fat storage.Some MP impacts were similar to those of naturally occurring organic and inorganicparticles, whilst others represented a risk over and above that associated with naturalparticles.The number of MP impacts detected in our experiments provides sufficient basis for“moving beyond the precautionary principle” when motivating a need for monitoringand management – there is now sufficient evidence that MPs alter key aspects of thefunctioning of stream benthic food webs to motivate a need for action.Based on our results, we further provide a series of recommendations formonitoring,policy and management targeting MPs, and for future research.
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| 33. |
-
Membrane technologies for water treatment : Removal of toxic trace elements with emphasis on arsenic, fluoride and uranium
- 2016
-
Samlingsverk (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- Focuses on the application of membrane technologies in removing toxic metals\metalloids from water. Particular attention is devoted to the removal of arsenic, uranium, and fluoride. These compounds are all existing in the earth's crust at levels between two and five thousands micrograms per kg (parts per million) on average and these compounds can be considered highly toxic to humans, who are exposed to them primarily from air, food and water. In order to comply with the new maximum contaminant level, numerous studies have been undertaken to improve established treatments or to develop novel treatment technologies for removing toxic metals from contaminated surface and groundwater. Among the technologies available, applicable for water treatment, membrane technology has been identified as a promising technology to remove such toxic metals from water. The book describes both pressure driven (traditional processes, such as Nanofiltration, Reverse Osmosis, Ultrafiltration,etc) and more advanced membrane processes (such as forward osmosis, membrane distillation, and membrane bio-reactors) employed in the application of interest. Key aspect of this book is to provide information on both the basics of membrane technologies and on the results depending on the type of technology employed.
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| 34. |
- Mukherjee, A., et al.
(författare)
-
Tectonic-sourced groundwater arsenic in Andean foreland of Argentina : Insight from flow path modeling
- 2014
-
Ingår i: One Century of the Discovery of Arsenicosis in Latin America (1914-2014). - : CRC Press. - 9781138001411 ; , s. 22-25
-
Konferensbidrag (refereegranskat)abstract
- The groundwater arsenic enriched Chaco-Pampean plain of Argentina is located in the active foreland of continental arc dominated Andean orogenic belt. Rhyolitic volcanic glass fragments are a major component of the aeolian-fluvial aquifer sediments, which is dotted with many hot springs that are related to the palaeo-igneous extrusion in the vicinity. Several Salinas in the areas may have originated because of the tectonic evolution of the region. Hydrogeochemical analyses, thermodynamic mixing diagrams and flow path modeling analyses of groundwater samples collected from the Santiago del Estero province suggest that predominant evolutionary processes of the groundwater include chemical weathering with monosialitization silicate of weathering and evaporate dissolution. Anorthite, albite and As-enriched volcanic glass seems to contribute to the major dissolution phases. Subsequently, co-introduced oxyions mobilized the solid-phase As to groundwater by competitive ion exchanged. Further liberation might have taken place by counter-ion activity due to transition of the Ca-rich to Na-rich groundwater due to groundwater mixing with recharged brackish surface water from Salinas or by evaporative concentration due to the prevailing arid climate.
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| 35. |
- Ormachea Muñoz, Mauricio, et al.
(författare)
-
Geogenic arsenic and other trace elements in the shallow hydrogeologic system of Southern Poopó Basin, Bolivian Altiplano
- 2013
-
Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 262, s. 924-940
-
Tidskriftsartikel (refereegranskat)abstract
- Environmental settings in the southern area of Lake Poopó in the Bolivian highlands, the Altiplano, have generated elevated amounts of arsenic (As) in the water. The area is characterised by a semiarid climate, slow hydrological flow and geologic formations of predominantly volcanic origin. The present study aimed at mapping the extent of the water contamination in the area and to investigate the geogenic sources and processes involved in the release of As to the groundwater.Ground- and surface-water samples were collected from 24 different sites, including drinking water wells and rivers, in the southern Poopó basin in two different field campaigns during the dry and rainy seasons. The results revealed variable levels of As in shallow drinking water wells and average concentration exceeding the WHO guidelines value. Arsenic concentrations range from below 5.2μg/L (the detection level) to 207μg/L and averages 72μg/L. Additionally, high boron (B) concentrations (average 1902μg/L), and high salinity are further serious concerns for deteriorating the groundwater quality and rendering it unsuitable for drinking. Groundwater is predominantly of the Na-Cl-HCO3 type or the Ca-Na-HCO3 type with neutral or slightly alkaline pH and oxidising character. While farmers are seriously concerned about the water scarcity, and on a few occasions about salinity, there are no concerns about As and B present at levels exceeding the WHO guidelines, and causing negative long term effects on human health.Sediment samples from two soil profiles and a river bed along with fourteen rock samples were also collected and analysed. Sequential extractions of the sediments together with the calculation of the mineral saturation indices indicate that iron oxides and hydroxides are the important secondary minerals phases which are important adsorbents for As. High pH values, and the competition of As with HCO3 and dissolved silica for the adsorption sites probably seems to be an important process for the mobilisation of As in the shallow groundwaters of the region. Continuous monitoring and expansion of monitoring systems are necessary prerequisites for better understanding of the pattern of As mobilisation in the Southern Poopó Basin.
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| 36. |
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| 37. |
- Ramos Ramos, O. E., et al.
(författare)
-
Geochemical processes controlling mobilization of arsenic and Trace Elements in shallow aquifers in mining regions, Bolivian Altiplano
- 2014
-
Ingår i: One Century of the Discovery of Arsenicosis in Latin America (1914-2014). - : CRC Press. - 9781138001411 ; , s. 239-241
-
Konferensbidrag (refereegranskat)abstract
- A geochemical approach was applied to understand the factors controlling the mobilization of As and trace elements (TEs) in these mining areas. A total of 30 samples (wells and geothermal water) were collected during the rainy season (2009). As, Cd and Mn concentrations exceed WHO drinking guidelines in some groundwater samples, but Cu, Ni, Pb and Zn do not. Factor analysis of the groundwater chemical data suggests the following geochemical processes: i) plagioclase weathering, ii) dissolution of gypsum and halite, iii) trace element mobilization at acidic pH, iv) sulfide oxidation, and v) release of As following competition with phosphate and bicarbonate for adsorption sites. The As and TEs mobilized in these regions could affect the local water sources, which is a prevalent concern with respect to water resource management in this semi-arid Altiplano region.
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| 38. |
- Ramos Ramos, Oswaldo Eduardo, et al.
(författare)
-
Sources and behavior of arsenic and trace elements in groundwater and surface water in the Poopó Lake Basin, Bolivian Altiplano
- 2012
-
Ingår i: Environmental Earth Sciences. - : Springer Science and Business Media LLC. - 1866-6280 .- 1866-6299. ; 66:3, s. 793-807
-
Tidskriftsartikel (refereegranskat)abstract
- Water management in semiarid and arid catchments such as the Poopó Lake Basin requires improved understanding of the complex behavior of the various contaminants, which affect the drinking water quality and considered as crucial for sustainable development of the region. Mechanisms of arsenic (As) release in the surface and groundwater were studied. Hydrochemical data for surface water (4 samples) and groundwater (28 samples) were collected in a small watershed in the Poopó catchment at the highland of the Bolivian Andes (Altiplano). All of them show high electrical conductivity values and moderately oxidizing conditions. The surface water contains high concentration of sulfate and the trace elements As, Zn and Pb in the zone affected by acid mine drainage. There is a large variability of the concentration of As and of the trace elements in the groundwater in the five different regions within the Poopó catchment. The metal concentrations sensitive to changes of redox state and results of speciation modeling suggest that As (V) is a predominant aqueous species, which conforms to the prevailing oxidizing conditions in the shallow groundwater environment. Two generalized trends for As distribution were identified in groundwater: (a) high concentrations are found in the arid zone (100-250 Όg/L) in the southern (region III) and in the northwestern (region V) regions, and (b) low concentrations (< 50 Όg/L) are found in the remaining part of the basin (region I, II and IV). However, the spatial distribution within these regions needs to be investigated further. A conclusion from the present study is that there are multiple sources of As as well as other trace elements (such as Cd, Mn and Zn) in the Poopó Lake Basin. Among the sources and the processes which led to the mobility of As and other trace metals in the region are: (a) weathering of sulfide minerals, (b) oxidation of pyrite and/or arsenopyrite in mineralized areas and (c) desorption from hydrous ferric oxide (HFO) surfaces. In non-mining areas, volcanic ash is suggested to be a significant source of As.
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| 39. |
- Sayeed, A., et al.
(författare)
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Handwashing with soap : A concern for overuse of water amidst the COVID-19 pandemic in Bangladesh
- 2021
-
Ingår i: Groundwater for Sustainable Development. - : Elsevier BV. - 2352-801X. ; 13, s. 100561-
-
Tidskriftsartikel (refereegranskat)abstract
- Handwashing is one of the vital public health measures. It helps to prevent the spread of the COVID-19 pandemic. However, water overuse during hand scrubbing with soap keeping the tap on may put enormous pressure on the already overstretched groundwater resources and households’ economic well-being. Therefore, this study aimed to determine the overuse of water while scrubbing hands with soap for handwashing when the tap is on amid the COVID-19 pandemic in Bangladesh. Sociodemographic data were collected using a web-based survey tool among 1980 participants and an experiment was conducted among 126 participants to estimate the overuse of water during hand scrubbing while the tap is on. A total of 80% of the participants washed their hands regularly after returning home from outside. About 57.3% of participants did not turn off their tap throughout the handwashing process. A single participant, who kept his tap on throughout the handwashing process, overused approximately 1.7 L of water per handwash and 14.9 L of water per day. Hand scrubbing with soap keeping the tap on, raised the overuse of water 13-fold during this pandemic compared to the non-pandemic situation which cost an extra 225.0 BDT (2.7$) per day for 1980 participants. Minimize the speed of tap, using automatic taps, and using taps operated by legs might be an effective solution to reduce the water overuse. Furthermore, behavioral change interventions are needed to aware people turn off the tap during hand scrubbing with soap.
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| 40. |
- Schneider, J., et al.
(författare)
-
Arbuscular mycorrhizal fungi-assisted phytoremediation of a lead-contaminated site
- 2016
-
Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 572, s. 86-97
-
Tidskriftsartikel (refereegranskat)abstract
- Knowledge of the behavior of plant species associated with arbuscular mycorrhizal fungi (AMF) and the ability of such plants to grow on metal-contaminated soils is important to phytoremediation. Here, we evaluate the occurrence and diversity of AMF and plant species as well as their interactions in soil contaminated with lead (Pb) from the recycling of automotive batteries. The experimental area was divided into three locations: a non-contaminated native area, a coarse rejects deposition area, and an area receiving particulate material from the chimneys during the Pb melting process. Thirty-nine AMF species from six families and 10 genera were identified. The Acaulospora and Glomus genera exhibited the highest occurrences both in the bulk (10 and 6) and in the rhizosphere soils (9 and 6). All of the herbaceous species presented mycorrhizal colonization. The highest Pb concentrations (mg kg− 1) in roots and shoots, respectively, were observed in Vetiveria zizanoides (15,433 and 934), Pteris vitata (9343 and 865), Pteridim aquilinun (1433 and 733), and Ricinus communis (1106 and 625). The diversity of AMF seems to be related to the area heterogeneity; the structure communities of AMF are correlated with the soil Pb concentration. We found that plant diversity was significantly correlated with AMF diversity (r = 0.645; P > 0.05) in areas with high Pb soil concentrations. A better understanding of AMF communities in the presence of Pb stress may shed light on the interactions between fungi and metals taking place in contaminated sites. Such knowledge can aid in developing soil phytoremediation techniques such as phytostabilization.
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| 41. |
- Schneider, J., et al.
(författare)
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Potential of different AM fungi (native from As-contaminated and uncontaminated soils) for supporting Leucaena leucocephala growth in As-contaminated soil
- 2017
-
Ingår i: Environmental Pollution. - : Elsevier Ltd. - 0269-7491 .- 1873-6424. ; 224, s. 125-135
-
Tidskriftsartikel (refereegranskat)abstract
- Arbuscular mycorrhizal (AM) fungi inoculation is considered a potential biotechnological tool for an eco-friendly remediation of hazardous contaminants. However, the mechanisms explaining how AM fungi attenuate the phytotoxicity of metal(oid)s, in particular arsenic (As), are still not fully understood. The influence of As on plant growth and the antioxidant system was studied in Leucaena leucocephala plants inoculated with different isolates of AM fungi and exposed to increasing concentrations of As (0, 35, and 75 mg dm−3) in a Typic Quartzipsamment soil. The study was conducted under greenhouse conditions using isolates of AM fungi selected from uncontaminated soils (Acaulospora morrowiae, Rhizophagus clarus, Gigaspora albida; and a mixed inoculum derived from combining these isolates, named AMF Mix) as well as a mix of three isolates from an As-contaminated soil (A. morrowiae, R. clarus, and Paraglomus occultum). After 21 weeks, the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) were determined in the shoots in addition to measuring plant height and mineral contents. In general, AM fungi have shown multiple beneficial effects on L. leucocephala growth. Although the activity of most of the stress-related enzymes increased in plants associated with AM fungi, the percentage increase caused by adding As to the soil was even greater for non-mycorrhizal plants when compared to AM-fungi inoculated ones, which highlights the phytoprotective effect provided by the AM symbiosis. The highest P/As ratio observed in AM-fungi plants, compared to non-mycorrhizal ones, can be considered a good indicator that the AM fungi alter the pattern of As(V) uptake from As-contaminated soil. Our results underline the role of AM fungi in increasing the tolerance of L. leucocephala to As stress and emphasize the potential of the symbiosis L. leucocephala-R. clarus for As-phytostabilization at moderately As-contaminated soils.
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| 42. |
- Zhu, Y. -G, et al.
(författare)
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Editors’ foreword
- 2018
-
Ingår i: Environmental Arsenic in a ChangingWorld - 7th International Congress and Exhibition Arsenic in the Environment, 2018. - : CRC Press/Balkema. ; , s. xlv-xlvi
-
Konferensbidrag (refereegranskat)
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