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1.
Cureus ; 16(1): e51484, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38304670

RESUMEN

This case report highlights a very rare variant of diaphragmatic hernia, namely, an intrapericardial diaphragmatic hernia, which can arise as a complication of the convergence procedure. A 77-year-old man, presenting with chronic shortness of breath and fatigue, was unexpectedly found to have herniation of the transverse colon into the pericardial cavity through a diaphragmatic-pericardial defect. The diaphragmatic defect was repaired with mesh via robotic surgery. The patient reported resolution of his symptoms at the six-month follow-up.

2.
Environ Sci Pollut Res Int ; 31(10): 15026-15038, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38285260

RESUMEN

Enterprises across the globe are facing increasing pressure to effectively utilize resources and reduce costs through green supply chain practices. Emerging technology, such as blockchain technology which enables green practices, has become a contemporary industrial paradigm. However, enterprises need to build green intellectual capital to implement blockchain technology, which can be key to realizing green supply chain practices. This research examines the impact of green intellectual capital (GIC) on blockchain technology and its role in implementing green manufacturing to achieve sustainability. Partial least squares structural equation modeling was utilized for assessing the proposed hypotheses, and cross-sectional data was accumulated from manufacturing firms. As per the results, GIC, which includes green human capital, green structural capital, and green relational capital has a crucial role in the implementation of blockchain technology. The outcomes also indicated that the adoption of blockchain technology significantly influences green manufacturing. Moreover, green manufacturing (GM) has a substantial role in improving business sustainability. This empirical research provides a deeper understanding of how GIC and blockchain technology contribute to the implementation of GM. This research also provides guidelines that managers, policymakers, and producers can use to facilitate the incorporation of GM practice into business activities.


Asunto(s)
Cadena de Bloques , Humanos , Estudios Transversales , Comercio , Industrias , Tecnología
3.
Food Sci Nutr ; 11(6): 3485-3496, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37324903

RESUMEN

The mandate of the current investigation was to elucidate the therapeutic and antioxidant perspective of black tea. Purposely, black tea compositional analysis followed by polyphenol extraction and antioxidant characterization was done. Moreover, the theaflavin from black tea extract was also isolated through the solvent partition method. Lastly, the neuroprotective effect of isolated theaflavin was assessed through a bio-efficacy trial. The outcomes delineated that black tea showed promising nutritional composition with special reference to protein and fiber. Among the extraction solvent, ethanol performed better as compared to methanol and water likewise, higher extraction was noticed at 60 min followed by 90 and 30 min. All the extracts indicated antioxidant activity reflected through significant DPPH, TPC, FRAP, and beta carotene as-69.13 ± 3.00, 1148.92 ± 14.01, 752.44 ± 10.30, and 65.74 ± 3.28, respectively. However, isolated theaflavin exhibited higher antioxidant capacity as-737.74 ± 12.55, 82.60 ± 2.33, and 853.77 ± 9.55, for TPC, DPPH, and FRAP, respectively, as compared to extracts. In 15 days' efficacy was physically induced with sciatic nerve injury h sciatic nerve injury physically and treated with isolated theaflavin. A total of 12 healthy albino mice were randomly assigned to either the control (n = 6) or theaflavin (5.0 mg/kg (n = 6)) groups. In these groups, behavioral tests were used to assess and compare enhanced functional recovery as well as skeletal muscle mass measurement. Serum samples included oxidative stress markers. In theaflavin leaves, behavioral tests revealed a statistically significant (p < .001) improvement in sensorimotor function restoration, muscle mass restoration, a substantial decrease in TOS, a significant increase in TAC, and enhanced antioxidative enzyme activity. Considering the above-mentioned therapeutic perspectives of theaflavin, the current research was planned to optimize the isolation of theaflavin from black tea and probed for their neuroprotective effect in mice models.

4.
Food Sci Nutr ; 10(11): 3544-3561, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36348778

RESUMEN

Carvacrol is a major natural constituent and is significantly present as an essential oil in aromatic plants and is well known for its numerous biological activities. Therapeutic properties of carvacrol have been demonstrated as anti-oxidant, anticancer, diabetes prevention, cardioprotective, anti-obesity, hepatoprotective and reproductive role, antiaging, antimicrobial, and immunomodulatory properties. The carvacrol biosynthesis has been mediated through mevalonate pathway. Carvacrol has the anticancer ability against malignant cells via decreasing the expressions of matrix metalloprotease 2 and 9, inducing apoptosis, enhancing the expression of pro-apoptotic proteins, disrupting mitochondrial membrane, suppressing extracellular signal-regulated kinase 1/2 mitogen-activated protein kinase signal transduction, and also decreasing the phosphoinositide 3-kinase/protein kinase B. It also decreased the concentrations of alanine aminotransferase, alkaline phosphatase and aspartate aminotransferase, and gamma-glutamyl transpeptidase as well as also restored liver function, insulin level, and plasma glucose level. Carvacrol also has been found to exert antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, Coagulase-negative staphylococcus, Salmonella spp., Enterococcus sp. Shigella, and Escherichia coli. The current review article summarizes the health-promoting perspectives of carvacrol through various pathways.

5.
Front Nutr ; 9: 940514, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35938114

RESUMEN

Cancer is a severe condition characterized by uncontrolled cell division and increasing reported mortality and diagnostic cases. In 2040, an estimated 28.4 million cancer cases are expected to happen globally. In 2020, an estimated 19.3 million new cancer cases (18.1 million excluding non-melanoma skin cancer) had been diagnosed worldwide, with around 10.0 million cancer deaths. Breast cancer cases have increased by 2.26 million, lung cancer by 2.21 million, stomach by 1.089 million, liver by 0.96 million, and colon cancer by 1.93 million. Cancer is becoming more prevalent in Pakistan, with 19 million new cancer cases recorded in 2020. Food adulteration, gutkha, paan, and nutritional deficiencies are major cancer risk factors that interplay with cancer pathogenesis in this country. Government policies and legislation, cancer treatment challenges, and prevention must be revised seriously. This review presents the current cancer epidemiology in Pakistan to better understand cancer basis. It summarizes current cancer risk factors, causes, and the strategies and policies of the country against cancer.

6.
Chemosphere ; 307(Pt 2): 135732, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35872057

RESUMEN

Geogenic contamination of groundwater is frequently associated with gold mining activities and related to drinking water quality problems worldwide. In Tanzania, elevated levels of trace elements (TEs) have been reported in drinking water sources within the Lake Victoria Basin, posing a serious health risk to communities. The present study aims to assess the groundwater quality with a focus on the concentration levels of geogenic contaminants in groundwater around the Lake Victoria goldfields in Geita and Mara districts. The water samples were collected from community drinking water sources and were analysed for physiochemical parameters (pH, EC, Eh), major ions, and trace elements. The analysed major ions included Na+, K+, Ca2+, Mg2+, SO42-, HCO3- and Cl- whereas the trace elements were As, Al, Li, Ba, B, Ti, V, U, Zr, Sr, Si, Mn Mo, Fe, Ni, Zn, Cr, Pb, Cd, and V. The present study revealed that the concentration levels of the major ions were mostly within the World Health Organization (WHO) drinking water standards in the following order of their relative abundance; for cations, Ca2+∼Na+>Mg2+>K+ and for anions was HCO3- > SO42- > NO3-, Cl- > PO43-. Statistical and geochemical modelling software such as 'R Studio', IBM SPSS, geochemical workbench, visual MINTEQ were used to understand the groundwater chemistry and evaluate its suitability for drinking purpose. The concentration of As in groundwater sources varies between below detection limit (bdl) and 300 µg/L, with highest levels in streams followed by shallow wells and boreholes. In approximately 48% of the analysed samples, As concentration exceeded the WHO drinking water guideline and Tanzania Bureau of Standards (TBS) guideline for drinking water value of 10 µg/L. The concentration of the analyzed TEs and mean values of physicochemical parameters were below the guideline limits based on WHO and TBS standards. The Canadian Council of Ministries of the Environment Water Quality Index (CCME WQI) shows that the overall water quality is acceptable with minimum threats of deviation from natural conditions. We recommend further geochemical exploration and the periodic risk assessment of groundwater in mining areas where high levels of As were recorded.


Asunto(s)
Agua Potable , Agua Subterránea , Oligoelementos , Contaminantes Químicos del Agua , Cadmio/análisis , Canadá , Agua Potable/análisis , Monitoreo del Ambiente , Oro/análisis , Agua Subterránea/análisis , Lagos/análisis , Plomo/análisis , Tanzanía , Oligoelementos/análisis , Contaminantes Químicos del Agua/análisis , Calidad del Agua
7.
Sci Total Environ ; 810: 152153, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34864037

RESUMEN

Groundwater contamination from geogenic sources poses challenges to many countries, especially in the developing world. In Tanzania, the elevated fluoride (F-) concentration and related chronic fluorosis associated with drinking F- rich water are common in the East African Rift Valley regions. In these regions, F- concentration is space dependence which poses much uncertainty when targeting safe source for drinking water. To account for the spatial effects, integrated exploratory spatial data analysis, regression analysis, and geographical information systems tools were used to associate the distribution of F- in groundwater with spatial variability in terrain slopes, volcanic deposits, recharge water/vadose materials contact time, groundwater resource development for irrigated agriculture in the Sanya alluvial plain (SAP) of northern Tanzania. The F- concentration increased with distance from steep slopes where the high scale of variation was recorded in the gentle sloping and flat grounds within the SAP. The areas covered with debris avalanche deposits in the gentle sloping and flat grounds correlated with the high spatial variability in F- concentration. Furthermore, the high spatial variability in F- correlated positively with depth to groundwater in the Sanya flood plain. In contrast, a negative correlation between F- and borehole depth was observed. The current irrigation practices in the Sanya alluvial plain contribute to the high spatial variability in F- concentration, particularly within the perched shallow aquifers in the volcanic river valleys. The findings of this study are important to the overall chain of safe water supply process in historically fluorotic regions. They provide new insights into the well-known F- contamination through the use of modern geospatial methods and technologies. In Tanzania's context, the findings can improve the current process of drilling permits issuance by the authority and guide the local borehole drillers to be precise in siting safe source for drinking water.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Fluoruros/análisis , Tanzanía , Contaminantes Químicos del Agua/análisis
8.
Food Sci Nutr ; 9(4): 2066-2074, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33841824

RESUMEN

Dates (Phoenix dactylifera L.) are rich in nutritional compounds, particularly in sugars. Sugars offer anaerobic fermentation, used for bioethanol production. Recently, researchers and industrialists finding ways to produce low-cost bioethanol on large scale using agricultural wastes. Date palm residual is the largest agricultural waste in Pakistan, which can be the cheapest source for bioethanol production, whereas the current study was designed to explore the possible utilization and the potential of date palm waste for bioethanol production through Saccharomyces cerevisiae grown in yeast extract, Bacto peptone, and d-glucose medium. The fermentation process resulted in the production of 15% (v/v) ethanol under the optimum condition of an incubation period of 72 hr and three sugars (glucose, fructose, and sucrose) were found in date waste. The functional group of ethanol (C2H5OH) was also found via Fourier-transform infrared spectroscopy (FTIR) analysis. Therefore, S. cerevisiae could be recommended for ethanol production due to short fermentation time at 25% inoculum in 30°C and reduced the processing cost. Common date varieties of low market value are a preferred substrate for the process of producing industrial ethanol. Additionally, proximate analysis of date fruit by near-infrared spectroscopy revealed moisture contents (16.84%), crude protein (0.3%), ash (9.8%), crude fat (2.6%), and neutral detergent fibers (13.4%). So, date fruit contains various nutrients for microbial growth for ethanol production.

9.
Curr Pollut Rep ; 7(2): 160-166, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33842197

RESUMEN

The episodic outbreak of COVID-19 due to SARS-CoV-2 is severely affecting the economy, and the global count of infected patients is increasing. The actual number of patients had been underestimated due to limited facilities for testing as well as asymptomatic nature of the expression of COVID-19 on individual basis. Tragically, for emerging economies with high population density, the situation has been more complex due to insufficient testing facilities for diagnosis of the disease. However, the recent reports about persistent shedding of viral RNA of SARS-CoV-2 in the human feces have created a possibility to track the prevalence and trends of the disease in communities, known as wastewater-based epidemiology (WBE). In this article, we highlight the current limitations and future prospects for WBE to manage pandemics.

10.
Sci Total Environ ; 773: 145040, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33581647

RESUMEN

Arsenic (As) contamination is a well-recognized environmental and health issue, threatening over 200 million people worldwide with the prime cases in South and Southeast Asian and Latin American countries. Rice is mostly cultivated under flooded paddy soil conditions, where As speciation and accumulation by rice plants is controlled by various geo-environmental (biotic and abiotic) factors. In contrast to other food crops, As uptake in rice has been found to be substantially higher due to the prevalence of highly mobile and toxic As species, arsenite (As(III)), under paddy soil conditions. In this review, we discussed the biogeochemical cycling of As in paddy soil-rice system, described the influence of critical factors such as pH, iron oxides, organic matter, microbial species, and pathways affecting As transformation and accumulation by rice. Moreover, we elucidated As interaction with organic and inorganic amendments and mineral nutrients. The review also elaborates on As (im)mobilization processes and As uptake by rice under the influence of different mineral nutrients and amendments in paddy soil conditions, as well as their role in mitigating As transfer to rice grain. This review article provides critical information on As contamination in paddy soil-rice system, which is important to develop suitable strategies and mitigation programs for limiting As exposure via rice crop, and meet the UN's key Sustainable Development Goals (SDGs: 2 (zero hunger), 3 (good health and well-being), 12 (responsible consumption and production), and 13 (climate action)).


Asunto(s)
Arsénico , Oryza , Contaminantes del Suelo , Arsénico/análisis , Humanos , Minerales , Nutrientes , Suelo , Contaminantes del Suelo/análisis
11.
Environ Sci Pollut Res Int ; 28(1): 1108-1130, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32833173

RESUMEN

This study aims to evaluate the quality of groundwater in the most arid province of Iran, Yazd. It is highly dependent on groundwater resources to meet the domestic, industrial, and agricultural water demand. Position of water samples on the modified Gibbs diagram demonstrates that the interaction with silicates and the increase in direct cation exchange are responsible for the increased salinity of groundwater. Based on entropy theory, the decreasing order of importance of variables in controlling groundwater chemistry is Fe > As > Ba > Hg > NO2 > Pb > K > Cl > Na > Mg > SO4 > NO3 > HCO3 > Ca. The results of entropy weighted water quality index (EWWQI) calculation show that about 34 and 32% of 206 samples in the wet and dry seasons, respectively, are classified as extremely poor quality (ranks 4 and 5). Approximately 60 and 55% of 206 samples in wet and dry seasons, respectively, have excellent, good, and medium quality (ranks 1, 2, and 3). The non-carcinogenic human health risk (NHHR) from intake and dermal contact pathways using deterministic approach show that 36 and 17 samples in both seasons are not suitable for drinking by children. Furthermore, 9 and 2 samples are not suitable for drinking by adults. The results show that children are more vulnerable than adults to these health risks. The non-carcinogenic risks through dermal contact were negligible.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Adulto , Niño , Monitoreo del Ambiente , Humanos , Irán , Medición de Riesgo , Contaminantes Químicos del Agua/análisis , Calidad del Agua
12.
J Hazard Mater ; 405: 123885, 2021 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-33183836

RESUMEN

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/ß/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.


Asunto(s)
Arsénico , Fenómenos Biológicos , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Arsénico/análisis , Humanos , Peróxido de Hidrógeno
13.
Environ Sci Technol ; 54(23): 15454-15464, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33174730

RESUMEN

Effective arsenic (As) removal from groundwater is a pressing need in view of increasingly stringent As drinking water limits in some US states and European countries. In this study, we compared the addition of weak (O2), intermediate (NaOCl), and strong (KMnO4) groundwater oxidants on the fate of As during As(III), Fe(II), and Mn(II) co-oxidation. Experiments were performed with 50 µg/L As(III), 5 mg/L Fe(II), and 0.5 mg/L Mn(II) in solutions containing relevant groundwater ions, with the reaction products characterized by As K-edge X-ray absorption spectroscopy (XAS). Adding O2 by aeration was the least effective method, unable to decrease As to below 10 µg/L, which was attributed to inefficient As(III) oxidation. Dosing NaOCl (55 µM) consistently removed As to <10 µg/L (and often <5 µg/L). The As K-edge XAS data of the NaOCl samples indicated complete As(III) oxidation and As(V) sorption to coprecipitated hydrous ferric oxide (HFO) in the binuclear, bridging (2C) complex. The most effective As removal was observed with KMnO4 (40 µM), which completely oxidized As(III) and yielded residual As concentrations that were less than (by as much as 50%) or equal to the NaOCl experiments. Furthermore, the average As-metal bond length of the KMnO4 solids (RAs-Fe/Mn = 3.24 ± 0.02 Å) was systematically shorter than the NaOCl solids (RAs-Fe/Mn = 3.29 ± 0.02 Å), consistent with As(V) sorption to both MnO2 and HFO. These findings can be used to optimize groundwater As treatment to meet relevant drinking water guidelines, while considering the As uptake mode and characteristics of the particle suspension (i.e., colloidal stability and filterability).


Asunto(s)
Arsénico , Agua Subterránea , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Europa (Continente) , Compuestos Férricos , Compuestos Ferrosos , Compuestos de Manganeso , Oxidación-Reducción
14.
NPJ Biofilms Microbiomes ; 6(1): 43, 2020 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-33097725

RESUMEN

Phosphate dosing is used by water utilities to prevent plumbosolvency in water supply networks. However, there is a lack of knowledge regarding biofilm formation on lead and plastic materials when phosphate concentrations are modified in drinking water systems. In this study, biofilms were grown over lead coupons and PVC tubes in bioreactors supplied with local drinking water treated to provide different phosphate doses (below 1, 1 and 2 mg/L) over a period of 28 days. A range of commercial iron pellets (GEH104 and WARP) were tested aiming to maintain phosphate levels below the average 1 mg/L found in drinking water. Changes in biofilm community structure in response to three different phosphate treatments were characterised by Illumina sequencing of the 16S rRNA gene for bacteria and the ITS2 gene for fungi. Scanning electron microscopy was used to visualise physical differences in biofilm development in two types of materials, lead and PVC. The experimental results from the kinetics of phosphate absorption showed that the GEH104 pellets were the best option to, in the long term, reduce phosphate levels while preventing undesirable turbidity increases in drinking water. Phosphate-enrichment promoted a reduction of bacterial diversity but increased that of fungi in biofilms. Overall, higher phosphate levels selected for microorganisms with enhanced capabilities related to phosphorus metabolism and heavy metal resistance. This research brings new insights regarding the influence of different phosphate concentrations on mixed-species biofilms formation and drinking water quality, which are relevant to inform best management practices in drinking water treatment.


Asunto(s)
Bacterias/clasificación , Biopelículas/crecimiento & desarrollo , Cloro/farmacología , Agua Potable/microbiología , Hongos/clasificación , Fosfatos/metabolismo , Bacterias/genética , Bacterias/aislamiento & purificación , Biopelículas/clasificación , Reactores Biológicos/microbiología , ADN Bacteriano/genética , ADN de Hongos/genética , ADN Ribosómico/genética , Hongos/genética , Hongos/aislamiento & purificación , Secuenciación de Nucleótidos de Alto Rendimiento , Plomo/química , Microscopía Electrónica de Rastreo , Plásticos/química , ARN Ribosómico 16S/genética , Purificación del Agua , Calidad del Agua
16.
Water Res ; 178: 115826, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32361349

RESUMEN

In this study we investigate opportunities for reducing arsenic (As) to low levels, below 1 µg/L in produced drinking water from artificially infiltrated groundwater. We observe that rapid sand filtration is the most important treatment step for the oxidation and removal of As at water treatment plants which use artificially recharged groundwater as source. Removal of As is mainly due to As co-precipitation with Fe(III)(oxyhydr)oxides, which shows higher efficiency in rapid sand filter beds compared to aeration and supernatant storage. This is due to an accelerated oxidation of As(III) to As(V) in the filter bed which may be caused by the manganese oxides and/or As(III) oxidizing bacteria, as both are found in the coating of rapid sand filter media grains by chemical analysis and taxonomic profiling of the bacterial communities. Arsenic removal does not take place in treatment steps such as granular activated carbon filtration, ultrafiltration or slow sand filtration, due to a lack of hydrolyzing iron in their influent and a lack of adsorption affinity between As and the filtration surfaces. Further, we found that As reduction to below 1 µg/L can be effectively achieved at water treatment plants either by treating the influent of rapid sand filters by dosing potassium permanganate in combination with ferric chloride or by treating the effluent of rapid sand filters with ferric chloride dosing only. Finally, we observe that reducing the pH is an effective measure for increasing As co-precipitation with Fe(III)(oxyhydr)oxides, but only when the oxidized arsenic, As(V), is the predominant species in water.


Asunto(s)
Arsénico , Agua Potable , Agua Subterránea , Contaminantes Químicos del Agua , Purificación del Agua , Compuestos Férricos , Filtración , Oxidación-Reducción , Dióxido de Silicio
17.
Sci Total Environ ; 715: 136671, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32050319

RESUMEN

Elevated Arsenic (As) and Fluoride (F) concentrations in groundwater have been studied in the shallow aquifers of northeastern of La Pampa province, in the Chaco-Pampean plain, Argentina. The source of As and co-contaminants is mainly geogenic, from the weathering of volcanic ash and loess (rhyolitic glass) that erupted from the Andean volcanic range. In this study we have assessed the groundwater quality in two semi-arid areas of La Pampa. We have also identified the spatial distribution of As and co-contaminants in groundwater and determined the major factors controlling the mobilization of As in the shallow aquifers. The groundwater samples were circum-neutral to alkaline (7.4 to 9.2), oxidizing (Eh ~0.24 V) and characterized by high salinity (EC = 456-11,400 µS/cm) and Na+-HCO3- water types in recharge areas. Carbonate concretions ("tosca") were abundant in the upper layers of the shallow aquifer. The concentration of total As (5.6 to 535 µg/L) and F (0.5 to 14.2 mg/L) were heterogeneous and exceeded the recommended WHO Guidelines and the Argentine Standards for drinking water. The predominant As species were arsenate As(V) oxyanions, determined by thermodynamic calculations. Arsenic was positively correlated with bicarbonate (HCO3-), fluoride (F), boron (B) and vanadium (V), but negatively correlated with iron (Fe), aluminium (Al), and manganese (Mn), which were present in low concentrations. The highest amount of As in sediments was from the surface of the dry lake. The mechanisms for As mobilization are associated with multiple factors: geochemical reactions, hydrogeological characteristics of the local aquifer and climatic factors. Desorption of As(V) at high pH, and ion competition for adsorption sites are considered the principal mechanisms for As mobilization in the shallow aquifers. In addition, the long-term consumption of the groundwater could pose a threat for the health of the local community and low cost remediation techniques are required to improve the drinking water quality.

18.
J Hazard Mater Lett ; 1: 100001, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34977840

RESUMEN

Increased concern has recently emerged pertaining to the occurrence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in aquatic environment during the current coronavirus disease 2019 (COVID-19) pandemic. While infectious SARS-CoV-2 has yet to be identified in the aquatic environment, the virus potentially enters the wastewater stream from patient excretions and a precautionary approach dictates evaluating transmission pathways to ensure public health and safety. Although enveloped viruses have presumed low persistence in water and are generally susceptible to inactivation by environmental stressors, previously identified enveloped viruses persist in the aqueous environment from days to several weeks. Our analysis suggests that not only the surface water, but also groundwater, represent SARS-CoV-2 control points through possible leaching and infiltrations of effluents from health care facilities, sewage, and drainage water. Most fecally transmitted viruses are highly persistent in the aquatic environment, and therefore, the persistence of SARS-CoV-2 in water is essential to inform its fate in water, wastewater and groundwater and subsequent human exposure.

19.
Environ Int ; 134: 105253, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31810053

RESUMEN

Arsenic (As) is a highly toxic element which naturally occurs in drinking water. In spite of substantial evidence on the association between many illnesses and chronic consumption of As, there is still a considerable uncertainty about the health risks due to low As concentrations in drinking water. In the Netherlands, drinking water companies aim to supply water with As concentration of <1 µg/L - a water quality goal which is tenfold more stringent than the current WHO guideline. This paper provides (i) an account on the assessed lung cancer risk for the Dutch population due to pertinent low-level As in drinking water and cost-comparison between health care provision and As removal from water, (ii) an overview of As occurrence and mobility in drinking water sources and water treatment systems in the Netherlands and (iii) insights into As removal methods that have been employed or under investigation to achieve As reduction to <1 µg/L at Dutch water treatment plants. Lowering of the average As concentration to <1µg/L in the Netherlands is shown to result in an annual benefit of 7.2-14 M€. This study has a global significance for setting drinking water As limits and provision of safe drinking water.


Asunto(s)
Agua Potable/química , Arsénico , Monitoreo del Ambiente , Agua Subterránea , Países Bajos , Contaminantes Químicos del Agua , Abastecimiento de Agua
20.
Sci Total Environ ; 690: 778-789, 2019 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-31302543

RESUMEN

An overview about the presence of arsenic (As) in groundwaters of Argentina, made by a transdisciplinary group of experts is presented. In this second part, the conventional and emerging technologies for As removal, management of wastes, and the initial investment costs of the proposed technologies, with emphasis on developments of local groups are described. Successful examples of real application of conventional and emerging technologies for As removal in waters for human consumption, for medium, small and rural and periurban communities are reported. In the country, the two most applied technologies for arsenic removal at a real scale are reverse osmosis and coagulation-adsorption-filtration processes using iron or aluminum salts or polyelectrolytes as coagulants. A decision tree to evaluate the possible technologies to be applied, based on the population size, the quality of the water and its intended use, is presented, including preliminary and indicative investment costs. Finally, a section discussing the treatment and final disposal of the liquid, semiliquid and solid wastes, generated by the application of the most used technologies, is included. Conclusions and recommendations, especially for isolated rural and periurban regions, have been added.

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