32 research outputs found
Biomonitoring of Hg0, Hg2 and Particulate Hg in a Mining Context Using Tree Barks+
The biomonitoring of atmospheric mercury (Hg) is an important topic in the recent scientific literature given the cost-benefit advantage of obtaining indirect measurements of gaseous Hg using biological tissues. Lichens, mosses, and trees are the most commonly used organisms, with many standardized methods for some of them used across European countries by scientists and pollution regulators. Most of the species used the uptake of gaseous Hg (plant leaves), or a mixture of gaseous and particulate Hg (mosses and lichens), but no method is capable of differentiating between main atmospheric Hg phases (particulate and gaseous), essential in a risk assessment. The purpose of this work was to evaluate different uptake patterns of biological tissues in terms of atmospheric Hg compounds. To accomplish this, the feasibility of two plant tissues from a tree commonly found in urban environments has been evaluated for the biomonitoring of gaseous Hg species in a Hg mining environment. Sampling included leaves and barks from Platanus hispanica and particulate matter from the atmosphere of the urban area around Almadén (south-central Spain), while analytical determinations included data for total Hg concentrations in biological and geological samples, Hg speciation data and total gaseous Hg (TGM). The results allowed us to identify the main Hg compounds in leaves and bark tissues and in atmospheric particulate matter, finding that leaves bioaccumulated only gaseous Hg (Hg0 and Hg2+), preferably during daylight hours, whereas the barks accumulated a combination of TGM and particulate bound Hg (PBM) during the day and at night. Subsequent merging of the atmospheric Hg speciation data obtained from leaves and barks allowed indicative maps of the main sources of TGM and PBM emissions to be obtained, thereby perfectly delimiting the main TGM and PBM sources in the urban area around Almadén. This method complements TGM biomonitoring systems already tested with other urban trees, adding the detection of PBM emission sources and, therefore, biomonitoring all Hg species present in the atmosphere. Scenarios other than mining sites should be evaluated to determine the utility of this method for Hg biospeciation in the atmosphere
The mersade (European Union) project: testing procedures and environmental impact for the safe storage of liquid mercury in the Almadén district, Spain.
The MERSADE Project (LIFE--European Union) tested the Las Cuevas decommissioned mining complex (Almadén mercury district, Spain) as a potential site for the installation of a future European prototype safe deposit of surplus mercury from industrial activities. We here present the results of a baseline study on the distribution of mercury in soils and air in the Las Cuevas complex and surrounding areas, and show the results of a plume contamination model using the ISC-AERMOD software. Despite restoration works carried out in 2004, the Las Cuevas complex can still be regarded as hotspot of mercury contamination, with large anomalies above 800 microg g(-1) Hg (soils) and 300 ng Hg m(-3) (air). In the case of soils, high, and persistent concentrations above 26 microg g(-1) Hg extend well beyond the complex perimeter for more than 2 km. These concentrations are about three orders of magnitude above world baselines. The same applies to mercury in air, with high concentrations above 300 ng Hg m(-3) inside the perimeter, which nonetheless fade away in a few hundred meters. Air contamination modelling (Hg gas) predicts formation of a NW-SE oriented narrow plume extending for a few hundred meters from the complex perimeter. The geographic isolation of Las Cuevas and its mining past make the complex an ideal site for mercury stocking. The only potential environmental hazards are the raising of livestock only a few hundred meters away from the complex and flash floods
Consideraciones ambientales sobre el mercurio en el distrito minero de Almadén (Ciudad Real, España).
Los yacimientos de mercurio del Distrito minero de Almadén representan una singularidad mundial, al ser el único caso de un metal, el mercurio (Hg), que ha sido obtenido en una tercera parte de su producción mundial a partir de un solo yacimiento. El Distrito está formado por una serie de yacimientos de cinabrio (HgS), entre los que la mina de Almadén constituye el mayor de ellos. Los yacimientos se habrían formado como consecuencia de procesos geológicos actuando a lo largo del Paleozoico superior, pudiendo ser agrupados en dos tipos: los yacimientos de ?Tipo Almadén? y los yacimientos de ?Tipo Las Cuevas?.
Los yacimientos habrían estado expuestos a la erosión atmosférica desde tiempo antes de la llegada de la actividad minera, lo que implica que tanto antes de esta actividad como evidentemente durante ésta se produciría la diseminación en el medio ambiente de los productos de este proceso, en forma de lixiviados naturales y antropogénicos, de partículas de polvo conteniendo el mineral, así como de vapor de mercurio emitido a la atmósfera desde suelos conteniendo el elemento, escombreras, labores mineras, instalaciones metalúrgicas, etc.
Este trabajo presenta los diversos estudios llevados a cabo hasta la fecha sobre las implicaciones medioambientales y sobre la salud humana que se derivan de la presencia del metal disperso en el Distrito minero de Almadén (Ciudad Real)
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
Geodivulgar: Geología y Sociedad
Con el lema “Geología para todos” el proyecto Geodivulgar: Geología y Sociedad apuesta por la divulgación de la Geología a todo tipo de público, incidiendo en la importancia de realizar simultáneamente una acción de integración social entre estudiantes y profesores de centros universitarios, de enseñanza infantil, primaria, de educación especial y un acercamiento con público con diversidad funcional
4D dispersion of total gaseous mercury derived from a mining source: identification of criteria to assess risks related with high concentrations of atmospheric mercury
Mercury (Hg) is a global pollutant that can be transported long distances after its emission from primary sources. The most common problem of gaseous Hg in the vicinity of anthropogenic sources is its presence in inorganic forms and in the gaseous state in the atmosphere. Risk assessments related to the presence of gaseous Hg in the atmosphere at contaminated sites are often based on episodic and incomplete data, which do not properly characterize the Hg cycle in the area of interest or consider spatial or temporal terms. The aim of this work was to identify criteria to obtain the minimum amount of data with the maximum meaning and representativeness in order to delimit risk areas, both in a spatial and temporal respect. Data were acquired from May 2014 to August 2015 and included vertical and horizontal Hg measurements. A statistical analysis was carried out, and this included the construction of a model of vertical Hg movements that could be used to predict the location and timing of Hg inhalation risk. A monitoring strategy was designed in order to identify the relevant criteria, and this involved the measurement of gaseous Hg in a vertical section at low altitude (i.e. where humans are present) and in horizontal transects to appropriately characterize the transport cycle of gaseous Hg in the lower layers of the atmosphere. The measurements were carried out over time in order to obtain information on daily and seasonal variability. The study site selected was Almadenejos (Ciudad Real, Spain), a village polluted with mercury related to decommissioned mining and metallurgical facilities belonging to the Almadén mercury mining district.The vertical profiles revealed that higher total gaseous mercury concentrations are present at lower altitude during nocturnal hours and at higher altitude at dawn and dusk. On a daily basis the most important process involved in gaseous mercury movements is the mixing layer. Vertical transferences are predominant when this process is active, i.e. in all seasons except winter, while major sources act as constant suppliers of gaseous Hg to the mixing cell, thus producing Hg deposition at dusk. Conversely, horizontal transferences prevail during the hours of darkness and the main factors are major and minor sources, solar radiation, wind speed, and topography. The study has shown that it is important (i) to identify the sources, (ii) to get data about Hg movements in vertical and horizontal directions, (iii) to extend the measurements over time in a sufficiently representative way both daily and seasonally, and (iv) to determine the different populations of data to establish the background levels; this work proposes the use of Lepeltier graphs to do so.
In terms of risk assessment, the nights carry greater risk than the days in all seasons except autumn. The main factors involved in the creation of high-risk periods are those related to dilution (or its absence), namely wind speed and solar radiation at null levels.
The results of this study highlight the possible importance of relieving the distribution of gaseous mercury in proximity to discrete sources. Furthermore, systematic monitoring strategies can offer significant information for the Minamata Convention emission reduction scenario. Further studies, including a detailed topographic model of the area, are required in order to make precise estimations of the influence of this parameter, which appears in this study to be less important than the other factors but is still appreciable
Main factors affecting nocturnal maxima in daily cycles.
Mercury is considered to be a global pollutant and it has been globally transported as gaseous elemental mercury (GEM). International networks for the continuous monitoring of mercury, all of which are based on background sites, study the dispersion pattern of this metal and trends in its evolution in time and space. However, information about seasonal and daily cycling of polluted sites is scarce. The aim of the work described here was to cover this gap in knowledge. For this purpose, continuous (GEM) measurements were carried out in Almadén town from November 2011 to September 2013. Meteorological data were also collected during this time. GEM data show an average concentration during the sampling period (2011?2013) of 27.4 ng m?3, with a range of 0.8?686.9 ng m?3. The results highlighted seasonal and daily cycles of GEM in Almadén town, with seasonally higher levels in summer (686.9 ng m-3) and significantly daily higher levels during the night. A multiple linear regression model has established wind speed as the best GEM predictor in all seasons during the night, while the best predictor in winter is relative humidity, temperature in spring, solar radiation in summer and wind speed in autumn during the day. These results provide evidence that, in mining polluted sites like Almadén, photochemical reactions have a negligible impact on GEM levels during the daytime and that meteorological parameters are more relevant. Further studies on diurnal GEM cycling in polluted sites must be carried out to obtain a realistic local risk assessment, taking into account night GEM levels and their importance in each case study
Determinants of exposure to mercury in hair from inhabitants of the largest mercury mine in the world
Mercury exposure of the local population was assessed in two areas of the Almadén mercury mining district, Spain, which has been the world's largest producer of this element. Two groups, who are exposed to different sources of mercury, from a point source in Almadén and a diffuse source hundreds of kilometres away in the same region, were studied. Total mercury (THg) in human hair ranged from 0.20 to 9.35mgkg-1 and the mean value was 2.64mgkg-1. About 87% of subjects had THg levels in excess of the EPA reference dose (RfD=1.0mgkg-1), while a high percentage (68%) of them live in Almadén. There was a clear increase in hair Hg with reported fish consumption and the highest mean hair mercury level was 4 times the RfD in a group who had reported the highest consumption of fish. For the whole group, there was a significant effect of age, gender and fish consumption in relation to Hg concentration in the hair. Nevertheless, when both groups were tested separately by means of a multivariate regression model, there was significant exposure in those living near the mine area. Several factors such as age, gender and fish consumption remained statistically significant and were associated with THg. The main conclusion is that people living close to the hot spot are more impacted by mercury than people living further away. The intake of Hg through consumption of fish is an important parameter for Hg exposure; however, in the case of people living close to the hot spot, their levels are related to the highly Hg-impacted living environment. © 2011 Elsevier Ltd.Funding from Spanish Ministry of Science and Innovation (Grants CTM2006-13091 and CGL2009-13171) and from Castilla-La Mancha regional government – Viceconsejería de Universidades e Investigación (Grant PII1I09-0142-4389) is acknowledged. Luis Mansilla Plaza (EUP Almadén) collaborated in the sampling process. Núria Ribas collaborated in the early data treatment.Peer Reviewe
El Instituto de geología aplicada de la Universidad de Castilla-La Mancha se abre a la educación primaria. Una experiencia gratificante
Desde la creación del Instituto de Geología Aplicada de la Universidad de Castilla-La Mancha (IGeA), uno de sus objetivos principales ha sido la divulgación y el acercamiento de su actividad investigadora a otros colectivos docentes que no fueran los meramente universitarios. Con el fin de hacer frente a este objetivo nació el proyecto de colaboración didáctica con el Colegio de Educación Infantil y Primaria Hijos de Obreros de Almadén, cuyo título fue: «Almadén y el mercurio: ejemplo de sostenibilidad ambiental». En esta comunicación se describen las bases del proyecto didáctico y las actividades realizadas con el fin de generar provocaciones que despierten la reflexión, para hacer sentir a los estudiantes que son capaces de crear su propio aprendizaje, así como fomentar el interés por avanzar y emprender aventuras y proyectos innovadores comprometidos con ellos mismos y con su entorno, a través de la colaboración con un centro de investigación universitaria