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1.
Chemosphere ; 261: 127721, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32745740

RESUMEN

The uptake and distribution of Pb and the mechanisms involved in the metal tolerance have been investigated in a mine population of Biscutella auriculata. Seedlings were exposed to 125 µM Pb(NO3)2 for 15 days under semihydroponic conditions. The results showed an increase in the size of Pb-treated seedlings and symptoms of toxicity were not observed. ICP-OES analyses showed that Pb accumulation was restricted to root tissue. Imaging of Pb accumulation by dithizone histochemistry revealed the presence of the metal in vacuoles and cell wall in root cells. The accumulation of Pb in vacuoles could be stimulated by an increase in phytochelatin PC2 content. Pb did not promote oxidative damage and this is probably due the increase of antioxidative defenses. In the leaves, Pb produced a significant increase in superoxide dismutase activity, while in roots an increase in catalase and components of the Foyer- Halliwell-Asada cycle were observed. The results indicated that Biscutella auriculata has a high capacity to tolerate Pb and this is mainly due to a very efficient mechanism to sequester the metal in roots and a capacity to avoid oxidative stress. This species could therefore be very useful for phytostabilization and repopulation of areas contaminated with Pb.


Asunto(s)
Adaptación Fisiológica/efectos de los fármacos , Antioxidantes/metabolismo , Bioacumulación/efectos de los fármacos , Brassicaceae/metabolismo , Plomo/metabolismo , Minería , Contaminantes del Suelo/metabolismo , Biodegradación Ambiental , Brassicaceae/efectos de los fármacos , Brassicaceae/crecimiento & desarrollo , Catalasa/metabolismo , Plomo/análisis , Oxidación-Reducción , Estrés Oxidativo/efectos de los fármacos , Fitoquelatinas/metabolismo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/metabolismo , Contaminantes del Suelo/análisis
2.
Ecotoxicol Environ Saf ; 201: 110784, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32485494

RESUMEN

Biscutella auriculata L. is one of the rare species that is able to grow in a very contaminated mining area in Villamayor de Calatrava (Ciudad Real, Spain). In an effort to understand the mechanisms involved in the tolerance of this plant to high metal concentrations, we grew B. auriculata in the presence of 125 µM Cd(NO3)2 for 15 days and analysed different parameters associated with plant growth, nitric oxide and reactive oxygen species metabolism, metal uptake and translocation, photosynthesis rate and biothiol (glutathione and phytochelatins) content. Treatment with Cd led to growth inhibition in both the leaves and the roots, as well as a reduction of photosynthetic parameters, transpiration and stomatal conductance. The metal was mainly accumulated in the roots and in the vascular tissue, although most Cd was detected in areas surrounding their epidermal cells, while in the leaves the metal accumulated mainly in spongy mesophyll, stomata and trichrome. Based on the Cd bioaccumulation (5.93) and translocation (0.15) factors, this species denoted enrichment of the metal in the roots and its low translocation to the upper tissues. Biothiol analysis showed a Cd-dependent increase of reduced glutathione (GSH) as well as the phytochelatins (PC2 and PC3) in both roots and leaves. Cd-promoted oxidative damage occurred mainly in the leaves due to disturbances in enzymatic and nonenzymatic antioxidants, while the roots did not show significant damage as a result of induction of antioxidant defences. It can be concluded that B. auriculata is a new Cd-tolerant plant with an ability to activate efficient metal-sequestering mechanisms in the root surface and leaves and to induce PCs, as well as antioxidative defences in roots.


Asunto(s)
Adaptación Fisiológica/efectos de los fármacos , Brassicaceae/efectos de los fármacos , Cadmio/toxicidad , Minería , Contaminantes del Suelo/toxicidad , Antioxidantes/metabolismo , Brassicaceae/metabolismo , Cadmio/metabolismo , Glutatión/metabolismo , Modelos Teóricos , Oxidación-Reducción , Fotosíntesis/efectos de los fármacos , Fitoquelatinas/metabolismo , Hojas de la Planta/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Contaminantes del Suelo/metabolismo , España
3.
Chemosphere ; 201: 799-806, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29550574

RESUMEN

Mercury is considered a very toxic element and important efforts are currently being made aimed at reduce or even eliminating its usage. Despite this trend, there are still sites where contamination by this metal is very marked, especially in the mining environment of Almadén where it has been exploited for thousands of years. The several forms in which Hg occurs in the soil interact differently with the organisms that live in/on it. The soil is a place where many biotic and abiotic variables act together. Through a detailed study of the edaphic characteristics of a decommissioned metallurgical enclosure, the presence of different chemical forms of Hg, the study of microbial activity (DHA) and, finally, parameters of the vegetation cover, such as specific distribution and biomass, we have tried to elucidate the effect of the presence of Hg in this precinct with a very high Hg pollution. The obtained results showed the affection patterns by which the different measured parameters vary, with special incidence to the microbial activity of the topsoil and to the specific distribution of the plants found in the studied area. The statistical multivariate analysis showed that significant correlations have been found between soil Hg fractions and between Hg fractions in plants; furthermore, soil conditions seem to be not related with Hg transfer from soils to plants. Biomass and DHA data indicate that the studied area is not affected by the presence of Hg species and lacks the expected toxic effects on the living organisms.


Asunto(s)
Monitoreo del Ambiente/métodos , Mercurio/análisis , Minería , Microbiología del Suelo , Contaminantes del Suelo/análisis , Suelo/química , Biomasa , Metalurgia , Plantas/química , España
4.
Chemosphere ; 193: 74-81, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29127837

RESUMEN

Closure of chloralkali plants poses a risk of abandonment of important sources of gaseous mercury. In this work, an assessment has been made of the potential for pollution from one of these plants in the proximity of a densely populated town in central Romania. The work involved a comparison between two major types of monitoring survey: biomonitoring using leaves of a tree common in urban environments; and LUMEX-based gaseous mercury analysis. For biomonitoring, 21 samples from Salix alba L. trees were taken in Turda area. Atmospheric monitoring included two mobile surveys and one at a fixed location. The results from both monitoring systems show similarities in gaseous mercury dispersion patterns, with high mercury contents clearly related to the presence of the chloralkali plant. Particularly high levels were measured in the following situations: (i) in a 'smog' area related with thermal inversion and (ii) during dusk. Direct monitoring suffered from limitations in acquiring information, especially in a medium-long time range, but biomonitoring provided these data and is capable of covering studies on temporary trends or comparative assessments between European cities with contrasting gaseous mercury sources. The thermal speciation of mercury contents indicates that the whole fraction of mercury in leaves corresponds to organic mercury. This finding implies a non-reversible uptake process, which in turn ensures the applicability of this technique to biomonitor long-term exposure. As a conclusion, the assessment of gaseous mercury pollution based on biomonitoring using S. alba has proven to be a useful, reliable and cost-effective methodology.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Mercurio/análisis , Salix/fisiología , Ciudades , Gases/análisis , Plantas , Rumanía , Salix/crecimiento & desarrollo , Árboles
5.
Artículo en Francés | AIM (África) | ID: biblio-1258394

RESUMEN

L'utilisation d'un produit qui accélère la guérison après une chirurgie ou un traumatisme est une idée très attrayante. Après une destruction tissulaire, les facteurs de croissance se produisent naturellement pendant les phases de cicatrisation, de réparation ou de régénération tissulaire. L'injection d'un concentré plaquettaire est suivie d'une augmentation du facteur de croissance dans le site opératoire, ce qui permet une cicatrisation plus rapide. Ces facteurs de croissance sont libérés par la libération de plaquettes. Pour concentrer ces facteurs, il semble utile d'isoler les plaquettes, de les concentrer et de les réinjecter dans le site opératoire. Plusieurs techniques sont utilisées pour isoler les plaquettes telles que PRP, PRF et MPM. Tous ces produits sont à base de concentrés plaquettaires. Le résultat de ces produits est différent dans la concentration plaquettaire. Cependant, le temps et la vitesse d'essorage auront une influence sur la concentration plaquettaire. Nous savons que plus le temps et la vitesse de rotation sont courts, plus le nombre de plaquettes isolées est important. Nous avons essayé dans cette étude de déterminer le temps et la vitesse de rotation optimaux pour obtenir l'indice une concentration plus élevée de plaquettes


Asunto(s)
Centrifugación
6.
Sci Total Environ ; 408(20): 4901-5, 2010 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-20598346

RESUMEN

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.


Asunto(s)
Contaminantes Atmosféricos/análisis , Ambiente , Monitoreo del Ambiente/métodos , Mercurio/análisis , Contaminantes del Suelo/análisis , Contaminantes Atmosféricos/normas , Atmósfera/química , Recolección de Datos , Monitoreo del Ambiente/normas , Unión Europea , Residuos Peligrosos/análisis , Mercurio/normas , Contaminantes del Suelo/normas , España
7.
Sci Total Environ ; 387(1-3): 346-52, 2007 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-17590416

RESUMEN

We present data from a study of mercury concentrations in air and plant specimens from the MAF Herbarium in Madrid (Spain). Hg (gas) emissions from old plant collections treated with mercuric chloride (HgCl(2)) in herbaria may pose a health risk for staff working in installations of this type. This is an issue not yet properly addressed. Plants that underwent insecticide treatment with HgCl(2) at the MAF Herbarium until the mid 1970s have persistent high concentrations of Hg in the range 1093-11,967 microg g(-1), whereas untreated specimens are in the range of 1.2-4.3 microg g(-1). The first group induces high concentrations of Hg (gas) in the main herbarium room, with seasonal variations of 404-727 ng m(-3) (late winter) and 748-7797 ng m(-3) (early summer) (baseline for Hg: 8 ng m(-3)). A test survey at another herbarium in Madrid showed even higher concentrations of Hg (gas) above 40,000 ng m(-3). The World Health Organization guidelines for chronic exposure to Hg (gas) are estimated at a maximum of 1000 ng m(-3). While staff was aware of the existence of HgCl(2) treated plants (the plant specimen sheets are labelled as 'poisoned'), they had no knowledge of the presence of high Hg (gas) concentrations in the buildings, a situation that may be relatively common in herbaria.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Archivos , Mercurio/análisis , Desinfectantes , Cloruro de Mercurio , Proyectos Piloto , Plantas , Volatilización
8.
Environ Geochem Health ; 28(5): 431-43, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16752201

RESUMEN

The Elqui watershed (northern Chile) constitutes a highly contaminated river system, with arsenic exceeding by up to three orders of magnitude the average for river waters. There are three main reasons that explain this contamination: (1) the regional geology and hydrothermal (mineralizing) processes that developed in this realm during Miocene time; (2) the later unroofing-erosion-oxidation-leaching of As-Cu rich sulfide ores, a process that have been taking place for at least 10,000 years; and last but not least (3) mining activities at the high-altitude (>4000 m above sea level) Au-Cu-As El Indio mine, from the late 1970s onwards. The El Indio mineral deposit hosted large veins of massive sulfides, including the important presence of enargite (Cu(3)AsS(4)). The continuous natural erosion of these veins and their host rocks (also rich in As and Cu) during Holocene time, led to important and widespread metal dispersion along the river system. During the studied pre mining period (1975-1977), the high altitude river Toro waters already showed very large As concentrations (0.36-0.52 mg l(-1)). The initiation of full scale mining at El Indio (1980 onwards) led to an increase of these values, reaching a concentration of 1.51 mg l(-1) As in 1995. During the same year other rivers of the watershed reached peak As concentrations of 0.33 (Turbio) and 0.11 mg l(-1) (Elqui). These figures largely exceed the USEPA regulations for drinking water (0.01 mg l(-1) As), and about 10% of the total As data from the river Elqui (and 70% from the river Turbio) are above the maximum level allowed by the Chilean law for irrigation water (0.1 mg l(-1) As).


Asunto(s)
Arsénico/análisis , Cobre/análisis , Sedimentos Geológicos/química , Oro , Minería , Ríos/química , Contaminación Química del Agua/análisis , Chile , Monitoreo del Ambiente , Geografía , Fenómenos Geológicos , Geología , Concentración de Iones de Hidrógeno , Residuos Industriales/análisis , Hierro/análisis , Compuestos de Hierro/análisis , Minerales , Sulfatos/análisis
9.
Sci Total Environ ; 356(1-3): 112-24, 2006 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-15950266

RESUMEN

We present data from an early reconnaissance survey (stream sediments, soil, and water Hg chemistry; plants and water crustaceans Hg intake) of the Almadén district (central Spain), that was carried out to establish the potential environmental hazards derived from the anomalous mercury concentrations measured in this realm. The Almadén mercury district (approximately 300 km2) can be regarded as the largest geochemical anomaly of mercury on Earth. The district includes a series of mercury mineral deposits, having in common a simple mineralogy (dominant cinnabar: HgS, and minor pyrite: FeS2). The ore deposits have been mined for more than 2000 years, and the main mine of the district (Almadén), has been active from Roman times to present day with almost no interruptions. The mercury distribution in soils of the district reveals the existence of high, and extremely high mercury values (up to 8889 microg g(-1)), whereas concentrations in stream sediments and waters reach exceptional values of up to 16,000 microg g(-1) and 11,200 ng l(-1) respectively. On the other hand, very high concentrations of methylmercury (MeHg) have been detected in calcines (up to 3100 ng g(-1)), sediments (0.32-82 ng g(-1)), and waters (0.040-30 ng l(-1)). Mercury gets incorporated to edible river crustaceans and plants. The red swamp crayfish Procambarus clarkii, has Hg concentrations of up to 9060 ng g(-1) (muscle) and 26,150 ng g(-1) (hepatopancreas). Regarding plants, the local wild asparagus (Asparagus acutifolius) yields values of up to 298 microg g(-1) Hg. Mercury also escapes to the atmosphere, and mineral deposits, together with metallurgical activities, generate strong anomalies of atmospheric Hg. The most important concentrations relate to the emissions from the Almadén metallurgical roaster, in the order of 14,000 ng Hg m(-3). Additionally, large open pit operations also contribute to the district atmospheric pool of mercury, with high concentrations above 1000 ng Hg m(-3). Thus, no system (rocks, soils, sediments, waters, atmosphere, biota) in the Almadén district is free from strong Hg contamination.


Asunto(s)
Agua Dulce/análisis , Sedimentos Geológicos/análisis , Mercurio/análisis , Minería , Contaminantes del Suelo/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , España
10.
Aten Primaria ; 19(8): 412-7, 1997 May 15.
Artículo en Español | MEDLINE | ID: mdl-9254152

RESUMEN

OBJECTIVE: To find the views and approach of primary care professionals in this Health Area to questions referring to restrictions on tobacco consumption, possibilities of intervention and resources devoted to monitoring tobacco dependency. DESIGN: A crossover study using an anonymous self-administered questionnaire with closed replies. SETTING: Primary care professionals from the Guadalajara Health Area. PARTICIPANTS: Medical, nursing and other professional staff (361 people), with an 86.1% reply rate. MEASUREMENTS AND MAIN RESULTS: 90.7% thought it was a good idea that tobacco consumption was legally regulated, although only 54.3% of non-smokers and 49.7% of doctors were in favour of extending the law. 37.5% of doctors and 19.5% of nurses (at the expense above all of non-smokers) were in favour of prioritizing care for non-smokers. Over 85% considered useful or very useful the introduction of methods to combat dependency in Health Centres and among health staff. CONCLUSIONS: There is a broad consensus on restricting tobacco consumption in determined places and applying methods in primary care to facilitate giving up tobacco. A critical attitude to the state on its tobacco policy was noted.


Asunto(s)
Actitud del Personal de Salud , Atención Primaria de Salud , Tabaquismo/psicología , Adulto , Estudios Transversales , Femenino , Conocimientos, Actitudes y Práctica en Salud , Personal de Salud/estadística & datos numéricos , Humanos , Masculino , Prevalencia , Atención Primaria de Salud/estadística & datos numéricos , Cese del Hábito de Fumar/estadística & datos numéricos , España/epidemiología , Encuestas y Cuestionarios , Tabaquismo/epidemiología
11.
Rev Esp Salud Publica ; 70(1): 51-61, 1996.
Artículo en Español | MEDLINE | ID: mdl-8991702

RESUMEN

BACKGROUND: Tobaccoism is one of the most important social and health problems that exists. Given the role of Health Profesionals as educators and their example within the community, this particular group of people are vital in preventing and controlling tobaccoism. The purpose of this study was to identify the number and type of smokers working as professional health personnel in the Guadalajara Primary Medical Care Services, as well as their attitudes and knowledge in relation to the problem. METHODS: A descriptive cross-sectional study was carried out by means of a survey of all Guadalajara Primary Medical Care Personnel (doctors, nurses and other professionals). Data was compiled on social and demographic factors as well as the use of tobacco and awareness, attitudes and opinions: results were then analysed according to age, sex, occupation, working environment and degree of addiction. RESULTS: The rate of response was 86.1%. 38.2% claimed to be smokers (34.9% men and 41.2% women). Single male doctors living in urban areas showed the lowest rate of tobaccism. The majority of smokers did so at work, however not in front of patients, 63.2% had tried to give up smoking. The main cause of failure was attributed to lack of willpower (45.9%). 79.7% of ex-smokers had given up the habit after diagnosis of a health problem or illness. With respect to awareness and attitude, it was the medical profession and not tobaccoism itself that provided the most effective information and created less permissiveness in relation to the habit. Over 90% are in favour of initiating anti-smoking programs in Health Departments. CONCLUSIONS: A significant number of smokers in the sector was recorded, however attitudes towards the problem were positive.


Asunto(s)
Personal de Salud , Atención Primaria de Salud , Tabaquismo/epidemiología , Adulto , Estudios Transversales , Femenino , Humanos , Incidencia , Masculino , Factores Sexuales , Cese del Hábito de Fumar , España/epidemiología , Población Urbana
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