191 research outputs found

    Preliminary results of systematic sampling of gas manifestations in geodynamically active areas of Greece

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    Greece is located on a convergent plate boundary comprising the subduction of the African Plate beneath the Eurasian, while the Arabian plate approaches the Eurasian in a northwestward motion. It is considered to be one of the most tectonically active regions of Earth with a complex geodynamic setting, deriving from a long and complicated geological history. Due to this specific geological background, conditions for the formation of many thermal springs are favoured. In the past years, almost all the already known sites of degassing (fumaroles, soil gases, mofettes, gas bubbling in cold and thermal waters) located in the Hellenic area were sampled at least one time. Collected samples were analysed for their chemical (He, Ne, Ar, O2, N2, H2, H2S, CO, CH4 and CO2) and isotopic composition (He, C and N). Some of these sites have been selected for systematic sampling. Four of them have records longer than 10 years with tens of samplings also considering some literature data. Two of the sites are located in active volcanic areas (Santorini and Nisyros) while the other two are close to actively spreading graben structures with intense seismic activity (Gulf of Korinth and Sperchios basin). Results allowed to define long term background values and also some interesting variation related to seismic or volcanic activity

    Gas Geochemistry and Fractionation Processes in Florina Basin, Greece

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    Florina Basin is located in northern Greece, close to Mount Voras where the volcanic activity of Late Messinian age began. In the area, many CO2-rich gas emissions are present as a bubbling free-phase in groundwater (both springs and wells) and soil gases. Volcanism along with the geological and geodynamic regime of the basin, created the ideal conditions for CO2 accumulation in vertically stacked reservoirs. One of these, industrially exploited by the company Air Liquide Greece, produces 30,000 t/a of CO2. Results show that CO2 concentrations in the gases of Florina can arrive up to 99.8% and are mostly above 90%. Moreover, C-isotope composition (-2.1 to + 0.3 h vs. VPDB) indicates a mixed mantle-limestone origin for CO2, while He isotope composition (R/RA from 0.21 to 1.20) shows a prevailing crustal origin with an up to 15% mantle contribution. Helium and methane, with concentrations spanning over three orders of magnitude, show a positive correlation and a consequent high variability of He/CO2 and CH4/CO2 ratios. This variability can be attributed to the interaction of the uprising gases with groundwater that chemically fractionates them due to their different solubility. Based on the CO2, CH4 and He concentrations, gas samples collected in the basin can be divided in 3 groups: a) deep reservoir gases, b) enriched in less soluble gases and c) depleted in less soluble gases. The first group consists of gas samples collected at the Air Liquide extraction wells, which tap a 300m deep reservoir. This group can be considered as the least affected by fractionation processes due to interaction with groundwater. The gases of the second group due to their interaction with shallower unsaturated aquifers, become progressively enriched in less soluble gases (He and CH4). Finally, the third group represents residual gas phases after extensive degassing of the groundwater during its hydrological pathway

    Sex differences in mortality: results from a population-based study of 12 longitudinal cohorts.

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    BACKGROUND: Women generally have longer life expectancy than men but have higher levels of disability and morbidity. Few studies have identified factors that explain higher mortality in men. The aim of this study was to identify potential factors contributing to sex differences in mortality at older age and to investigate variation across countries. METHODS: This study included participants age ≥ 50 yr from 28 countries in 12 cohort studies of the Ageing Trajectories of Health: Longitudinal Opportunities and Synergies (ATHLOS) consortium. Using a 2-step individual participant data meta-analysis framework, we applied Cox proportional hazards modelling to investigate the association between sex and mortality across different countries. We included socioeconomic (education, wealth), lifestyle (smoking, alcohol consumption), social (marital status, living alone) and health factors (cardiovascular disease, diabetes, mental disorders) as covariates or interaction terms with sex to test whether these factors contributed to the mortality gap between men and women. RESULTS: The study included 179 044 individuals. Men had 60% higher mortality risk than women after adjustment for age (pooled hazard ratio [HR] 1.6; 95% confidence interval 1.5-1.7), yet the effect sizes varied across countries (I2 = 71.5%, HR range 1.1-2.4). Only smoking and cardiovascular diseases substantially attenuated the effect size (by about 22%). INTERPRETATION: Lifestyle and health factors may partially account for excess mortality in men compared with women, but residual variation remains unaccounted for. Variation in the effect sizes across countries may indicate contextual factors contributing to gender inequality in specific settings

    Geothermal mercury output at Nisyros Volcano (Greece)

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    Nisyros (Greece) is an active volcano in the eastern part of the South Aegean Active Volcanic Arc (SAAVA), hosting a high-enthalpy geothermal system. On June 2013, an extensive survey on Hg concentrations in different types of matrices (fumarolic fluids, atmosphere, soils and plants) was carried out at Lakki plain, an area affected by widespread soil degassing and fumarolic manifestations. To investigate the spatial distribution of mercury emission and its possible relationships with diffuse degassing of hydrothermal fluids, Hg concentrations in soils were related to their physicochemical parameters (e.g. temperature, soil-pH, hydrothermal gases and elemental C, N and S concentrations). Furthermore, leaves of Cistus and Erica (two local plants) were collected at the same sampling sites and their Hg contents were quantified. The concentrations of gaseous elemental mercury (GEM), H2S and CO2 were simultaneously measured in both the fumarolic emissions and in the atmosphere at the investigated sites. Mercury concentrations in the fumarolic gases ranged from 10,500 to 46,300 ng/m3, while the Hg concentrations in air showed high background values within the Lakki Plain caldera (from 10 to 36 ng/m3) with their maximum values (up to 7100 ng/m3) measured in the fumarolic areas. In the sites outside the caldera, the Hg concentrations in air were relatively low (from 2 to 5 ng/m3). A positive correlation between Hg and both CO2 and H2S values in the air exists, highlighting the important role of fumarolic and soil gases as carrier for GEM. On the other hand, soil Hg (concentrations from 0.023 to 13.7 g/g) showed no significant correlations with CO2 and H2S in the soil gases whereas a positive correlation with total S content and an inverse one with the soil-pH were noticed. These correlations evidenced the complexity of the processes involving Hg carried by hydrothermal gases while passing through the soil. Total Hg concentrations in plants, ranging from 0.010 to 0.112 g/g, had no direct correlation with soil Hg at the same sampling site. It is noteworthy that Cistus leaves presented higher values of total Hg than Erica leaves. Taking into consideration that Hg is a toxic element and is not readily absorbed by the roots, the main pathway of plant Hg uptake is probably transpiration through leaves; consequently, the higher specific leaf surface area of Cistus favoured Hg accumulation. Even though the GEM concentrations in air within the caldera of Nisyros are sometimes many orders of magnitude above the global background, the measured levels should not be considered dangerous for the human health. Values exceeding the WHO guideline value of 1000 ng/m3 are very rare (less than 0.1% of the measurements) and are only found in areas close to the main fumarolic vents, where the access to tourists is prohibited. Those areas are also characterized by elevated H2S concentrations, which are more dangerous than mercury\u2019s concentrations

    Household air pollution and blood pressure, vascular damage and sub-clinical indicators of cardiovascular disease in older Chinese adults

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    Background Limited data suggest that household air pollution from cooking and heating with solid fuel (i.e., coal and biomass) stoves may contribute to the development of hypertension and vascular damage. Methods Using mixed-effects regression models, we investigated the associations of household air pollution with blood pressure (BP) and vascular function in 753 adults (ages 40-79y) from three diverse provinces in China. We conducted repeated measures of participants’ household fuel use, personal exposure to fine particulate air pollution (PM2.5), BP, brachial-femoral pulse wave velocity (bfPWV), and augmentation index. Ultrasound images of the carotid arteries were obtained to assess intima-media thickness (CIMT) and plaques. Covariate information on socio-demographics, health behaviors, 24-h urinary sodium, and blood lipids was also obtained. Results Average estimated yearly personal exposure to PM2.5 was 97.5 μg/m 3 (SD: 79.2; range: 3.5-1241), and 65% of participants cooked with solid fuel. In multivariable models, current solid fuel use was associated with higher systolic (2.4 mmHg, 95%CI: -0.4, 4.9) and diastolic BP (1.4 mmHg, 95%CI: -0.1, 3.0) and greater total area of plaques (1.7 mm 2, 95%CI: -6.5, 9.8) compared with exclusive use of electricity or gas stoves. A 1-ln(µg/m 3) increase in PM2.5 exposure was associated with higher systolic (1.5 mmHg, 95%CI: 0.2, 2.7) and diastolic BP (1.0 mmHg, 95%CI: 0.4, 1.7) and with greater CIMT (0.02 mm, 95%CI: 0.00, 0.04) and total area of plaques (4.7 mm 2, 95%CI: -2.0, 11.5). We did not find associations with arterial stiffness, except for a lower bfPWV (-1.5 m/s, 95%CI: -3.0, -0.0) among users of solid fuel heaters. Conclusions These findings add to limited evidence that household air pollution is associated with higher BP and with greater CIMT and total plaque area

    Education and wealth inequalities in healthy ageing in eight harmonised cohorts in the ATHLOS consortium: a population-based study

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    Background: The rapid growth of the size of the older population is having a substantial effect on health and social care services in many societies across the world. Maintaining health and functioning in older age is a key public health issue but few studies have examined factors associated with inequalities in trajectories of health and functioning across countries. The aim of this study was to investigate trajectories of healthy ageing in older men and women (aged ≥45 years) and the effect of education and wealth on these trajectories. Methods: This population-based study is based on eight longitudinal cohorts from Australia, the USA, Japan, South Korea, Mexico, and Europe harmonised by the EU Ageing Trajectories of Health: Longitudinal Opportunities and Synergies (ATHLOS) consortium. We selected these studies from the repository of 17 ageing studies in the ATHLOS consortium because they reported at least three waves of collected data. We used multilevel modelling to investigate the effect of education and wealth on trajectories of healthy ageing scores, which incorporated 41 items of physical and cognitive functioning with a range between 0 (poor) and 100 (good), after adjustment for age, sex, and cohort study. Findings: We used data from 141 214 participants, with a mean age of 62·9 years (SD 10·1) and an age range of 45–106 years, of whom 76 484 (54·2%) were women. The earliest year of baseline data was 1992 and the most recent last follow-up year was 2015. Education and wealth affected baseline scores of healthy ageing but had little effect on the rate of decrease in healthy ageing score thereafter. Compared with those with primary education or less, participants with tertiary education had higher baseline scores (adjusted difference in score of 10·54 points, 95% CI 10·31–10·77). The adjusted difference in healthy ageing score between lowest and highest quintiles of wealth was 8·98 points (95% CI 8·74–9·22). Among the eight cohorts, the strongest inequality gradient for both education and wealth was found in the Health Retirement Study from the USA. Interpretation: The apparent difference in baseline healthy ageing scores between those with high versus low education levels and wealth suggests that cumulative disadvantage due to low education and wealth might have largely deteriorated health conditions in early life stages, leading to persistent differences throughout older age, but no further increase in ageing disparity after age 70 years. Future research should adopt a lifecourse approach to investigate mechanisms of health inequalities across education and wealth in different societies. Funding: European Union Horizon 2020 Research and Innovation Programme.The ATHLOS project was funded by the European Union Horizon 2020 Research and Innovation Programme (grant number 635316). This study was supported by the 5-year ATHLOS projec

    Active Moss biomonitoring of mercury in the mine-polluted area of Mt. Amiata (Central Italy)

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    In the winter 2013, mercury concentrations in air from the mine-polluted area of Mt. Amiata (1738 m a.s.l.), in southern Tuscany (Central Italy), were measured by active moss biomonitoring. This area is part of the geologic anomaly of Hg in the Mediterranean basin, which contains about 65 % of the world’s cinnabar (HgS). Mt. Amiata covers some 400 km2 and is drained by several rivers. Esploitation activity at Abbadia S. Salvatore, in the SE sector of the mountain, sprang up during the 19th century as one of the largest mercury mining and smelting plants in Europe, after those of Almaden Spain. In this area, Sphagnum moss bags were exposed for about two months, from October to December 2013. At each site (10 sites), one covered and one uncovered moss bag were deployed. Concentrations of mercury in air were also investigated in the same sites with a portable spectrophotometer (Lumex RA-915M). After exposure, mosses were oven-dried, grinded and each sample was divided in two aliquots: one was analyzed for mercury by using a Hydra C cold vapor atomic absorption analyzer (INGV-Palermo), following 7473 US EPA method; the second was microwave digested in acid solution (HNO3 + H2O2). Extraction solutions were analyzed by ICP-MS for total concentrations of a large suite of trace elements, including potentially toxic elements e.g. As, Cd, Cr, Cu, Mo, Sb, Se, V. Mercury air concentrations measured with the Lumex showed extremely high values in the mine district of Abbadia, with median values ranging from 2,000 to 4,000 ng/m3 and maximum values up to 20,000 ng/m3, in contrast with the lower values (median values from 20 to 200 ng/m3) measured in the distal sites few kilometres from the mine-district area. In agreement with these results, in the vicinity of the district uncovered bags were in the range of 10,000 – 100,000 ng/g of Hg, whereas in the distal sites they were in the range of 1,000 – 10,000 ng/g. The moss-blank (unexposed moss) was ~100 ng/g. Covered moss bags were not significantly enriched in Hg with respect to the concentrations recovered from the moss-blank, suggesting that the mercury trapped in the mosses was mainly in particulate form. The particles carried from the winds were probably associated with soils re-mobilization, as also confirmed by the associated enrichments of some lithophile elements (Li and lanthanides) and anthropogenic element (As, Cr, Cd, Fe, Se, V). These preliminary results confirm the intense contamination of the study area not only for mercury but also for other potentially toxic elements
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