80 research outputs found

    Impacto ambiental de la interacción agua-ceniza en la erupción del 2011 del volcán Grimsvötn (Islandia)

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    The Grímsvötn volcanic eruption, from 21 to 28 May, 2011, was the largest eruption of the Grímsvötn Volcanic System since 1873. The main geochemical features of the potential environmental impact of the volcanic ash-water interaction were determined using two different leaching methods as proxies (batch and vertical flow through column experiments). The main findings reveal that Na, K, Ca, Mg, Si, Cl, S and F show the largest geochemical fluxes caused by the interaction of water and ash. Additionally, the significant amounts of some of these elements (Ca, S and Mg) together with P, Cl, Fe, which are usually considered as macro/micronutrients, demonstrates the fertilising potential of the May 2011 emitted ash. On the other hand, release of F highlights the possible environmental problems arising from ash fallout on land or into fresh water syste ms. It is noteworthy that the chemical release is maximal during the first few hours of contact between tephra and water due to the dissolution of soluble salts from the ash surface. As time progresses, these constituents are exhausted, the release drops considerably and elements are freed instead by the incongruent dissolution of the volcanic glass.Este trabajo ha sido financiado por el proyecto QUECA (MINECO, CGL2011-23307).Peer Reviewe

    Caracterización geoquímica de los sedimentos de la red de drenaje del Rio Garona en la Val d'Aran (Catalunya, España).

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    A geochemical survey of stream sediments from the Garona River was performed in order to define the main regional lithogeochemical units and, based on this geochemical exploration study, to establish the reference levels of some chemical elements in the upper Garona River basin. The analysis of the lower grainsize fraction (˂180 μm) by HR-ICP-MS of 33 stream sediment samples allowed us establish reference levels for 48 elements. We have also studied the leachates of the sediments to model the environmentally available geochemical fraction. The trace elements with the lowest reference level, ranging between 10 and 50 mg/kg, are Th, Pr, Ga, Y, Ni, Pb, As, Cu, Zr, Li, Cr, Nd, La, and V. Instead, Zn, Rb, Sr, Ce and Ba show concentrations higher than 50 mg/kg. Some enrichments were observed in the streams sediments according to the three main litogeochemical units defined; the Maladeta-Marimanya granitoids (higher concentrations of Y, Th, Pb and U), the metasediments of an extensive area of the basin (enrichments in Pb, Sr and Sn), and the black shales (in Cu, U, Sr, Ni, Zn, V, Sb and Mo) which are present in local areas of the basin.SíPeer Reviewe

    Volcanic ash leaching as a means of tracing the environmental impact of the 2011 Grímsvötn eruption, Iceland

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    The Grímsvötn volcanic eruption, from 21 to 28 May, 2011, was the largest eruption of the Grímsvötn Volcanic System since 1873, with a Volcanic Explosivity Index (VEI) of magnitude 4. The main geochemical features of the potential environmental impact of the volcanic ash-water interaction were determined using two different leaching methods as proxies (batch and vertical flow-through column experiments). Ash consists of glass with minor amounts of plagioclase, clinopyroxene, diopside, olivine and iron sulphide; this latter mineral phase is very rare in juvenile ash. Ash grain morphology and size reflect the intense interaction of magma and water during eruption. Batch and column leaching tests in deionised water indicate that Na, K, Ca, Mg, Si, Cl, S and F had the highest potential geochemical fluxes to the environment. Release of various elements from volcanic ash took place immediately through dissolution of soluble salts from the ash surface. Element solubilities of Grímsvötn ash regarding bulk ash composition were <1 %. Combining the element solubilities and the total estimated mass of tephra (7.29 × 1014 g), the total inputs of environmentally important elements were estimated to be 8.91 × 109 g Ca, 7.02 × 109 g S, 1.10 × 109 g Cl, 9.91 × 108 g Mg, 9.91 × 108 g Fe and 1.45 × 108 g P The potential environmental problems were mainly associated with the release of F (5.19 × 109 g)

    Programa de educacion para la salud: cuidados y manejo de la enfermedad celiaca en edad escolar

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    La enfermedad celiaca (EC) es una forma de enteropatía que afecta a individuos genéticamente predispuestos, al entrar en contacto con alimentos que contienen gluten. Ello determina la aparición de una lesión histológica característica, que en las formas más graves provoca atrofia de las vellosidades intestinales. Como consecuencia puede producirse una mala absorción de nutrientes que conduce a estados carenciales responsables de varias manifestaciones clínicas. La EC puede presentarse a cualquier edad de la vida y cursa con manifestaciones clínicas muy variadas, en muchos casos la enfermedad es asintomática. Estas premisas hacen especialmente relevante el papel de la enfermera de atención primaria en el diagnóstico precoz, evitando así el desarrollo a largo plazo de complicaciones graves.<br /

    Volcanic ash leaching as a means of tracing the environmental impact of the 2011 Grímsvötn eruption, Iceland

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    The Grímsvötn volcanic eruption, from 21 to 28 May, 2011, was the largest eruption of the Grímsvötn Volcanic System since 1873, with a Volcanic Explosivity Index (VEI) of magnitude 4. The main geochemical features of the potential environmental impact of the volcanic ash-water interaction were determined using two different leaching methods as proxies (batch and vertical flow-through column experiments). Ash consists of glass with minor amounts of plagioclase, clinopyroxene, diopside, olivine and iron sulphide; this latter mineral phase is very rare in juvenile ash. Ash grain morphology and size reflect the intense interaction of magma and water during eruption. Batch and column leaching tests in deionised water indicate that Na, K, Ca, Mg, Si, Cl, S and F had the highest potential geochemical fluxes to the environment. Release of various elements from volcanic ash took place immediately through dissolution of soluble salts from the ash surface. Element solubilities of Grímsvötn ash regarding bulk ash composition were <1 %. Combining the element solubilities and the total estimated mass of tephra (7.29 × 1014 g), the total inputs of environmentally important elements were estimated to be 8.91 × 109 g Ca, 7.02 × 109 g S, 1.10 × 109 g Cl, 9.91 × 108 g Mg, 9.91 × 108 g Fe and 1.45 × 108 g P The potential environmental problems were mainly associated with the release of F (5.19 × 109 g)We gratefully acknowledge the assistance of ICTJA-CSIC labGEOTOP (infrastructure co-funded by ERDF-EU Ref. CSIC08-4E-001) and DRX (infrastructure co-funded by ERDF-EU Ref. CSIC10-4E-141) Surveys (J. Ibañez, J. Elvira and S. Alvarez) and the CCiTUB (SEM Unit) in the analytical work. Financial support was provided by the QUECA Project (MINECO, CGL2011-23307). We appreciate the invaluable comments of Dr. N. Olgun on a previous version of the manuscript. This study was carried out in the framework of the Research Consolidated Groups GEOPAM (Generalitat de Catalunya, 2014 SGR 869) and GEOVOL and the Associated Unit CSIC-UB UAGEPE (UA 285P01)Peer reviewe

    Influencia de las condiciones experimentales en la determinación de S, Cl, Br y I en agua por espectrometría de masas de alta resolución (HR-ICP-MS)

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    A systematic study was undertaken to optimize a method to determine S, Cl, Br and I in water by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). The sample composition and preparation conditions (the total dissolved solids -TDS-, the total organic compounds -TOC- and the addition of nitric acid) were evaluated to assess the sample matrix influence. Furthermore, the effect of instrumental parameters (carrier gas flow rate, sample flow rate, radiofrequency -RF- power and analyzer resolution) was also studied to minimize the contribution of polyatomic species, and to establish the required resolution. Low, medium or high resolutions were compared in terms of background level and sensitivity. After optimization, a multivariate robustness test was carried out by means of a Placket-Burman design. This method was applied to samples of the Llobregat and Ter rivers which are used for the drinking water system of the Metropolitan Area of Barcelona (~4.5 million inhabitants), Catalonia, northeast Spain.Este estudio fue financiado a través del Proyecto QUECA del Ministerio de Economía y Competitividad de España (CGL2011-23307) y el Proyecto PICT-2013-1259 (FONCyT, Argentina). Los análisis se realizaron en el Laboratorio de Geoquímica labGEOTOP en el ICTJA CSIC, infraestructura cofinanciada por FEDER-UE(Ref. CSIC08-4E-001).Peer Reviewe

    Ventajas y desventajas de la aplicación de la técnica de HR-ICP-MS al análisis inorgánico de aguas en terrenos volcánicos

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    La técnica de ICP-MS ha supuesto un gran avance en el análisis de aguas en los últimos decenios tal y como recogen las normativas al respecto en Europa, Estados Unidos, etc., habiéndose convertido en una técnica de referencia particularmente en el tema de calidad del agua. La alta resolución aplicada a la ICP-MS reduce considerablemente las interferencias y su combinación con detectores aptos para concentraciones mayoritarias hace que se disponga de una herramienta analítica muy competitiva que permite determinar simultáneamente elementos mayoritarios y trazas, incluidos halógenos (Cl, Br, I), y además relaciones isotópicas (ej., Li y B). Estos aproximadamente 60 parámetros geoquímicos permiten una caracterización exhaustiva de las aguas para temas de calidad y también ayudan a discernir más fácilmente el origen y el tránsito de las aguas a través de diferentes terrenos volcánicos. Por otra parte, la HR-ICP-MS es de gran aplicación a la determinación de los aportes geoquímicos volcanogénicos a los balances biogeoquímicos regionales, como por ejemplo de los materiales piroclásticos, a través del análisis de lixiviados procedentes de la simulación de la interacción del agua con estos productos eruptivos. En este trabajo se exponen los pros y contras de la aplicación de la HR-ICP-MS a aguas en problemáticas volcanogénicas a través de diferentes ejemplos (Islandia, Argentina, Chile, etc.). Agradecemos la asistencia del Servicio labGEOTOP (infraestructura cofinanciada por FEDER-UE, Ref. CSIC08-4E-001) del ICTJA-CSIC. La financiación fue proporcionada por QUECA (MINECO, CGL2011-23307). Este estudio se llevó a cabo en el marco del Grupo Reconocido GEOPAM (2014 SGR 869).La financiación fue proporcionada por QUECA (MINECO, CGL2011-23307). Este estudio se llevó a cabo en el marco del Grupo Reconocido GEOPAM (2014 SGR 869).Peer Reviewe

    Groundwater arsenic content in Raigón aquifer system (San José, Uruguay)

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    As a Medical Geology research issue, an environmental arsenic risk assessment study in the most important sedimentary aquifer in southern Uruguay is presented. The Raigón Aquifer System is the most exploited in Uruguay. It has a surface extent of about 1,800 square kilometres and 10,000 inhabitants in San Jose Department, where it was studied. Agriculture and cattle breeding are the main economic activities and this aquifer is the basic support. The groundwater sampling was done on 37 water samples of PRENADER (Natural Resources Management and Irrigation Development Program) wells. Outcropping sediments of Raigón Formation and the overlying Libertad Formation were also sampled in the Kiyú region. The analyses were performed by inductively coupled plasma-optical emission spectrometry (ICP-OES) and inductively coupled plasma-mass spectrometry (ICP-MS). The results showed 80% samples with arsenic levels exceeding the 10 μg/l of WHO as limit for waters, and 11% exceeds the 20 μg/l limit of uruguayan regulation. The median, maximum and minimum water arsenic concentrations determined have been 14.24, 24.19 and 1.44 μg/l, respectively. On the other hand, nine sediment samples of Raigón and Libertad Formations in Kiyú region were analysed and yielded median, maximum and minimum arsenic concentrations of 5.03, 9.82 and 1.18 ppm, respectively. This issue leads to the supposition that the population, as well as industrial and agricultural activities, are consuming water with arsenic concentrations over the national and international maximum recommended limit.Como una aproximación a la Geología Médica en Uruguay se presentan los resultados de un estudio sobre el estado del Sistema Acuífero Raigón en relación a la presencia de arsénico, en el entendido que es el acuífero más explotado en el país. En particular, el área cubierta por este trabajo es de unos 1800 km2 en un territorio con una población de unos 10,000 habitantes en el departamento de San José. La colecta de aguas del acuífero se realizó en perforaciones de la base de datos de PRENADER (Proyecto de Manejo de Recursos Naturales y Desarrollo del Riego) obteniéndose 37 muestras, y sobre 9 muestras de sedimentos tanto de la Formación Raigón como la suprayacente Libertad en afloramientos de la región de Kiyú. Los análisis fueron realizados mediante ICP-MS. Un 80% de las muestras de aguas analizadas mostraron contenidos mayores a los límites de la OMS (10 μg/l) y un 11% de las muestras superaron el límite de la OSE (20 μg/l). El valor medio, máximo y mínimo determinado en el caso del agua subterránea fue de 14.24, 24.19 and 1.44 μg/l, respectivamente. Por otro lado, las nueve muestras de sedimentos analizados mostraron concentraciones media, máxima y mínima de arsénico de 5.03, 9.82 and 1.18 ppm, respectivamente, descartándose en principio un origen geogénico.Cooperation between the University of the Republic (Uruguay) and CSIC from Spain (Ref. 2005UY0001). DINACYT-Uruguay, Project of the Technological Development Program PDT # 45/14 which included the doctoral thesis work of MSc. Rosario Guerequiz. CYTED Iberoarsen Network and the International Medical Geology Association contributed with scientific and technical support to improve the knowledge on environmental arsenic and health impacts, with a multidisciplinary approach in Uruguay. This work was performed under the Research Consolidated Groups SGR-2005-795 PEGEFA (Petrology and Geochemistry Basic and Applied) and SGR-2005-00589 (Mineral Resources), funded by AGAUR-DURSI, Generalitat de Catalunya.Peer reviewe

    Using Chemical Modeling to Asses Water Quality in the Raigón Aquifer System in Southern Uruguay

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    The Raigón aquifer is an important groundwater system in southern Uruguay. The increasing use of groundwater resources in the last decades has provoked changes in the concentration of many elements which are strongly related to anthropogenic pollution sources. Concentration levels are useful to detect changes in reservoir status but it is also necessary to analyze their chemical significance in order to make an accurate assessment of the sources of contamination and the causes of changes. In this work we use the available thermodynamic data to calculate chemical speciation on these groundwater samples. Trace elements present as anions, in particular Se and Mo, are especially focused to show the chemical modeling possibilities. Both elements form anionic species, predominantly MoO42- and SeO42-. Results show that these anions interact in solution and are greatly influenced by the concentration of the abundant calcium ion. Localized changes in pH can strongly affect the situation. The same is observed with the pE parameter, but only in the case of Se. Chemical speciation of trace elements is in general highly dependent on pH, pE and concentration of major elements. In consequence, for a fixed analytical total concentration, these parameters can markedly change the situation, affecting the mobility, the bioavailability and environmental fate of these elements. The strategy employed in this work can also be extended to the study of many other environmental water scenarios.The authors are grateful to CSIC (Programa de Apoyo a Grupos) and ANII (Project FCE_2011_6491), Uruguayan organizations, for financial support.Peer Reviewe

    Using Chemical Modeling to Asses Water Quality in the Raigón Aquifer System in Southern Uruguay

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    The Raigón aquifer is an important groundwater system in southern Uruguay. The increasing use of groundwater resources in the last decades has provoked changes in the concentration of many elements which are strongly related to anthropogenic pollution sources. Concentration levels are useful to detect changes in reservoir status but it is also necessary to analyze their chemical significance in order to make an accurate assessment of the sources of contamination and the causes of changes. In this work we use the available thermodynamic data to calculate chemical speciation on these groundwater samples. Trace elements present as anions, in particular Se and Mo, are especially focused to show the chemical modeling possibilities. Both elements form anionic species, predominantly MoO42- and SeO42-. Results show that these anions interact in solution and are greatly influenced by the concentration of the abundant calcium ion. Localized changes in pH can strongly affect the situation. The same is observed with the pE parameter, but only in the case of Se. Chemical speciation of trace elements is in general highly dependent on pH, pE and concentration of major elements. In consequence, for a fixed analytical total concentration, these parameters can markedly change the situation, affecting the mobility, the bioavailability and environmental fate of these elements. The strategy employed in this work can also be extended to the study of many other environmental water scenarios
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