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31.
In the Harghita volcanic range (Romania) there are many occurrences of dry CO(2) emanations, called mofettes. The emanating gas with high carbon dioxide content has a proved curative effect. The gas also contains important quantities of radon. Since the mofettes are used in curative purposes in several illnesses, in most of the cases without medical supervising, has been proposed to determine the radon activity concentration in some of the most frequented mofettes from Romania. The seasonal variations have also been monitored and were calculated the effective doses received by the patients during a cure. The radon activity concentrations' levels above the mofettes indoor air range between 548 and 10 717Bq/m(3) while within the gas pools' values between 3210 and 32 781Bq/m(3) have been measured. The effective dose received by the patients during a cure is between 0.0086 and 0.16mSv. No major seasonal variations of the radon activity concentrations levels have been pointed out so far in the studied mofettes. 相似文献
32.
Brominated flame retardants and organochlorines in the European environment using great tit eggs as a biomonitoring tool 总被引:1,自引:0,他引:1
Van den Steen E Pinxten R Jaspers VL Covaci A Barba E Carere C Cichoń M Dubiec A Eeva T Heeb P Kempenaers B Lifjeld JT Lubjuhn T Mänd R Massa B Nilsson JA Norte AC Orell M Podzemny P Sanz JJ Senar JC Soler JJ Sorace A Török J Visser ME Winkel W Eens M 《Environment international》2009,35(2):310-317
Large-scale studies are essential to assess the emission patterns and spatial distribution of organohalogenated pollutants (OHPs) in the environment. Bird eggs have several advantages compared to other environmental media which have previously been used to map the distribution of OHPs. In this study, large-scale geographical variation in the occurrence of OHPs, such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs), was investigated throughout Europe using eggs of a terrestrial residential passerine species, the great tit (Parus major). Great tit eggs from 22 sampling sites, involving urban, rural and remote areas, in 14 European countries were collected and analysed (5-8 eggs per sampling site). The environmentally most important congeners/compounds of the analysed pollutants were detectable in all sampling locations. For PCBs, PBDEs and OCPs, no clear geographical contamination pattern was found. Sum PCB levels ranged from 143 ng/g lipid weight (lw) to 3660 ng/g lw. As expected, PCB concentrations were significantly higher in the sampled urban compared to the remote locations. However, the urban locations did not show significantly higher concentrations compared to the rural locations. Sum PBDEs ranged from 4.0 ng/g lw to 136 ng/g lw. PBDEs were significantly higher in the urbanized sampling locations compared to the other locations. The significant, positive correlation between PCB and PBDE concentrations suggests similar spatial exposure and/or mechanisms of accumulation. Significantly higher levels of OCPs (sum OCPs ranging from 191 ng/g lw to 7830 ng/g lw) were detected in rural sampling locations. Contamination profiles of PCBs, PBDEs and OCPs differed also among the sampling locations, which may be due to local usage and contamination sources. The higher variance among sampling locations for the PCBs and OCPs, suggests that local contamination sources are more important for the PCBs and OCPs compared to the PBDEs. To our knowledge, this is the first study in which bird eggs were used as a monitoring tool for OHPs on such a large geographical scale. 相似文献
33.
Gergely Vodila Mihály Molnár Mihály Veres Éva Svingor István Futó István Barnabás Sándor Kapitány 《Journal of environmental radioactivity》2009
Püspökszilágy Radioactive Waste Treatment and Disposal Facility (RWTDF) is a typical near-surface engineered repository designated to store low- and intermediate-level wastes from various institutes, research facilities and hospitals in Hungary. Two automatic combined 14C–tritium sampling units installed at the facility sample the air 2 m above surface. The one installed near the vaults detects tritium (T) activities two orders of magnitude higher than the far reference sampling unit. To localize the T emissions, 19 small absorption vapour samplers filled with silica gel were settled onto the ground surface. After the saturation of the silica gel, the water was recovered and its T concentration was measured with a low-background liquid scintillation counter. The absorption vapour samplers are cheap, simple and easy-to-use. We present the samplers and the T distribution map constructed from the data, which helps to localize the T emission. 相似文献
34.
L. León Vintró P.I. Mitchell A. Omarova M. Burkitbayev H. Jiménez Nápoles N.D. Priest 《Journal of environmental radioactivity》2009
New data are reported on the concentrations, isotopic composition and speciation of americium, plutonium and uranium in surface and ground waters in the Sarzhal region of the Semipalatinsk Test Site, and an adjacent area including the settlement of Sarzhal. The data relate to filtered water and suspended particulate from (a) streams originating in the Degelen Mountains, (b) the Tel′kem 1 and Tel′kem 2 atomic craters, and (c) wells on farms located within the study area and at Sarzhal. The measurements show that 241Am, 239,240Pu and 238U concentrations in well waters within the study area are in the range 0.04–87 mBq dm−3, 0.7–99 mBq dm−3, and 74–213 mBq dm−3, respectively, and for 241Am and 239,240Pu are elevated above the levels expected solely on the basis of global fallout. Concentrations in streams sourced in the Degelen Mountains are similar, while concentrations in the two water-filled atomic craters are somewhat higher. Suspended particulate concentrations in well waters vary considerably, though median values are very low, at 0.01 mBq dm−3, 0.08 mBq dm−3 and 0.32 mBq dm−3 for 241Am, 239,240Pu and 238U, respectively. The 235U/238U isotopic ratio in almost all well and stream waters is slightly elevated above the ‘best estimate’ value for natural uranium worldwide, suggesting that some of the uranium in these waters is of test-site provenance. Redox analysis shows that on average most of the plutonium present in the microfiltered fraction of these waters is in a chemically reduced form (mean 69%; 95% confidence interval 53–85%). In the case of the atomic craters, the proportion is even higher. As expected, all of the americium present appears to be in a reduced form. Calculations suggest that annual committed effective doses to individual adults arising from the daily ingestion of these well waters are in the range 11–42 μSv (mean 21 μSv). Presently, the ground water feeding these wells would not appear to be contaminated with radioactivity from past underground testing in the Degelen Mountains or from the Tel′kem explosions. 相似文献
35.
Among all emerging substances in water, pharmaceutical products (PPs) and residues are a lot of concern. These last two years, the number of studies has increased drastically, however much less for water resources and drinking water than for wastewater. This literature review based on recent works, deals with water resources (surface or groundwater), focusing on characteristics, occurrence and fate of numerous PPs studied, and drinking water including water quality. Through this review, it appears that the pharmaceutical risk must be considered even in drinking water where concentrations are very low. Moreover, there is a lack of research for by-products (metabolites and transformation products) characterization, occurrence and fate in all water types and especially in drinking water. 相似文献
36.
Cristiano V.M. Araújo Fernando R. Diz Irene Laiz Luís M. Lubián Julián Blasco Ignacio Moreno-Garrido 《Environment international》2009,35(6):831-841
This study consisted of the sediment toxicity assessment of the Bay of Cádiz based on two endpoints: growth inhibition for Cylindrotheca closterium (benthic microalgae) and fecundity inhibition for Tisbe battagliai (harpacticoid copepod). A new methodology to eliminate (but not as storage technique) the autochthonous biota present in the sediment samples by immersing them in liquid nitrogen (? 196 °C) was also assessed. Sediment toxicity data showed different toxicity levels for both organisms. In general, T. battagliai was more sensitive; however a good correlation (r = 0.75; p < 0.05) between sediment toxicity results for both species was found. Data in pore water (pH, redox potential, and toxicity for microalgae and copepod) and sediment (pH, redox potential, organic carbon, and metal concentrations) demonstrated that ultra-freezing did not alter sample characteristics; thus, this technique can be adopted as a pre-treatment in whole-sediment toxicity tests in order to avoid misleading results due to presence of autochthonous biota. Multivariate statistical analysis such as cluster and principal component analysis using chemical and ecotoxicological data were employed. Silt and organic matter percentage and lead concentration were found to be the factors that explain about 77% of sediment toxicity in the Bay of Cádiz. Assay methodology determined in this study for both assayed species is considered adequate to be used in sediment toxicity monitoring programs. Results obtained using both species show that the Bay of Cádiz can be considered a moderately polluted zone. 相似文献
37.
Vo Thi Thanh Loc Simon R. Bush Le Xuan Sinh Nguyen Tri Khiem 《Environment, Development and Sustainability》2010,12(6):889-908
This paper investigates the structure, function and wealth distribution within the Pangasius hypophthalmus and Henicorhynchus spp./Labiobarbus spp. value chains in the Mekong Delta of Vietnam. The analysis is driven by key questions relating to the form and function
of value chains, their contribution to the livelihoods of farmers and fishers, the effectiveness of government policy and
the potential for value chain governance mechanisms, such as contracts and certification, to steer towards sustainable production.
The results indicate that actors in the high value Pangasius hypopthalmus export chain have a higher potential income, but face considerably higher economic vulnerability from global markets. Alternatively,
Henichorhychus/Labiobarbus spp. fishers are severely constrained in their ability to negotiate higher prices for their fish but appear to be less vulnerable
to economic and environmental change. The paper concludes that for value chain governance to improve the livelihoods of fishers
and farmers in both high and low value chains, new arrangements are needed that better accommodate customary institutions
and informal market relations. 相似文献
38.
Di Gregorio DE Huck H Aristegui R De Lazzari G Jech A 《Journal of environmental radioactivity》2004,76(3):273-281
Gamma-ray spectra from more than 50 samples of food products available in stores of Buenos Aires city were measured using a germanium detector. Activity concentrations of 137Cs up to 10 Bq/kg were found in tea and yerba mate manufactured in Apóstoles, Argentina. Further measurements of tea leaves, yerba mate leaves and soils, all coming from a cultivated area in that region, also show the presence of 137Cs contamination. The results suggest that the area was fertilized with a product that originated in a region affected by the fallout from the Chernobyl nuclear plant accident. 相似文献
39.
Gudrun Koppen Elly Den Hond Vera Nelen Els Van De Mieroop Liesbeth Bruckers Maaike Bilau Hans Keune Nicolas Van Larebeke Adrian Covaci Hendrik Van De Weghe Carmen Schroijen Kristine Desager Michel Stalpaert Willy Baeyens Greet Schoeters 《Environment international》2009,35(7):1015-1022
To collect regional information on internal levels of pollutants in humans in Flanders, 1196 mother–child pairs were systematically recruited in 2002–2003 via 25 maternities across Flanders. Cd, Pb, PCB congeners 118, 170, 138, 153 and 180, p,p′-DDE — a key metabolite of DDT- and hexachlorobenzene (HCB) were measured in cord blood or plasma. Cd was detected in 64% of the samples (geometric mean 0.21 µg/L cord blood). p,p′-DDE (110 ng/g plasma lipids) and Pb (14.7 µg/L blood), were measurable in nearly all samples. The individual PCB congeners could be detected in 40 to 81% of the newborns (138 + 153 + 180 = 64.4 ng/g plasma lipids). HCB (18.9 ng/g plasma lipids) and dioxin-like compounds measured by DR-CALUX® (23 pg CALUX-TEQ/g lipids) were above detection limit in more than 75% of the samples. Age and smoking habits of the mothers, did not influence the cord blood Pb and Cd levels. The organochlorines increased 4 to 9% per year of the mother's age (partial R2 = 0.05 to 0.22). Mothers had 2.6% less PCBs in cord blood (partial R2 = 0.02) for each unit increase in pre-pregnancy BMI. Season of delivery, breastfeeding previous children or consumption of local dairy products, were minor determinants. Up to 20% of the variability in organochlorine concentrations was explained by residence area. It was concluded that the place of birth in Flanders is an important determinant of the load of pollutants measured at the start of life. This underlines the validity of human biomonitoring on (relatively) small geographical scale. 相似文献
40.
Atmospheric bulk deposition to the lagoon of Venice Part I. Fluxes of metals, nutrients and organic contaminants 总被引:5,自引:0,他引:5
Rossini P Guerzoni S Molinaroli E Rampazzo G De Lazzari A Zancanaro A 《Environment international》2005,31(7):959-974
First available data on atmospheric fall-out were provided by sampling monthly bulk depositions in four sites inside the Lagoon of Venice (550 km2). Sampling was carried out monthly during the period July 1998-July 1999, in one site near an industrial area (Porto Marghera; site D), another site in the city of Venice (site A), and the remaining two in the southern- and northernmost ends of the Lagoon (Valle Figheri, site C; Valle Dogà site B). The following determinations were carried out for each samples: pH, conductivity, grain-size, particulate load, and dissolved nutrients (N, P). Samples were then subdivided into soluble and insoluble fractions, and Al, Ca, Na, K, Mg, Si, Mn, Fe, Zn, Ni, Cr, Cu, Pb, Cd, As, Hg, Ti, V, S, P, Se and Sb were analysed on both fractions. Total organic micropollutants (PAH, PCB, HCB, DDT, PCDD/F) were measured. As regards particle size distribution, there was great variability among sampling sites. The percentage of the < or =2 microm grain-size fraction was higher in the southern and northern ends of the Lagoon. Small differences were found among sites for major elements, whereas higher variability was observed for inorganic and organic micropollutants, with standard deviations between 20% and 60% of the fluxes measured. Major differences in annual fluxes between the most polluted sites (mostly D and A) and background (site B) were seen for Cd (0.26 vs. 0.06 mg m(-2) year(-1)), Hg (41 vs. 15 microg m(-2) year(-1)), PCB ( approximately 2500 vs. approximately 500 ng m(-2) year(-1)) and HCB ( approximately 8000 vs. approximately 1000 ng m(-2) year(-1)). Comparisons with previous data, collected in the periods 1993-1994 and 1995-1997, were only available for a few trace metals. A definite decline in the annual Pb flux in the city of Venice was detected, from 18 to 13 mg m(-2) in 1996/1997 and 1995/1996 respectively, to approximately 5 mg m(-2) in the present study. Total annual deposition was calculated by means of two different methods, which gave very similar results: (i) the mean value of deposition in the four sites was multiplied by lagoon area (550 km2); (ii) the monthly rain isopleths were combined to normalize deposition values. The figures are: 15-34 kg of Hg and Sb, approximately 200 kg of As, approximately 100 kg of Cd and PAH, 0.7-1.3 tons of Cr, Ni and V, more than 2 tons of Cu and Pb, 17 of Zn, 55 of total P, approximately 200 of Al, and 3900 of DIN. Total fluxes of organics inside the lagoon were: PAH approximately 100 kg; HCB approximately 1 kg; DDT approximately 0.4 kg. PCB and PCDD/F fluxes were approximately 500 g and approximately 10 g, corresponding respectively to 0.1 and 0.4 g I-TE. The correlations between fluxes of inorganic micropollutants and grain-size were significant. Multivariate statistical analysis was applied to investigate more accurately relationships between the insoluble and dissolved fractions of inorganic micropollutants and grain-size fractions. In particular, significant correlations were highlighted between the dissolved fraction of As and the < or =1 mum particle size fraction. Relations between levels of SigmaPCDDF, SigmaPCDD, PCB and PAH congeners and grain-size revealed significant correlation coefficients for the remote sites (B, C), and none in the urban and industrial sites (A, D). In particular, significant correlations were highlighted between SigmaPCDDF, SigmaPCDD and particle size fraction < or =2 mum, and between benzo(a)pyrene and PCB 167 and particle size fraction 4-8 mum. 相似文献