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Heavy metal and nitrogen concentrations in mosses are declining across Europe whilst some “hotspots” remain in 2010
2015
Harmens, H. | Norris, D.A. | Sharps, K. | Mills, G. | Alber R., | Aleksiayenak, Y. | Blum, O. | Cucu-Man, S.-M. | Dam, M. | De Temmerman, L. | Ene, A. | Fernández, J.A. | Martinez-Abaigar, J. | Frontasyeva, M. | Godzik, B. | Jeran, Z. | Lazo, P. | Leblond, S. | Liiv, S. | Magnússon, S.H. | Maňkovská, B. | Karlsson, G Pihl | Piispanen, J. | Poikolainen, J. | Santamaria, J.M. | Skudnik, M. | Spiric, Z. | Stafilov, T. | Steinnes, E. | Stihi, C. | Suchara, I. | Thöni, L. | Todoran, R. | Yurukova, L. | Zechmeister, H.G.
In recent decades, naturally growing mosses have been used successfully as biomonitors of atmospheric deposition of heavy metals and nitrogen. Since 1990, the European moss survey has been repeated at five-yearly intervals. In 2010, the lowest concentrations of metals and nitrogen in mosses were generally found in northern Europe, whereas the highest concentrations were observed in (south-)eastern Europe for metals and the central belt for nitrogen. Averaged across Europe, since 1990, the median concentration in mosses has declined the most for lead (77%), followed by vanadium (55%), cadmium (51%), chromium (43%), zinc (34%), nickel (33%), iron (27%), arsenic (21%, since 1995), mercury (14%, since 1995) and copper (11%). Between 2005 and 2010, the decline ranged from 6% for copper to 36% for lead; for nitrogen the decline was 5%. Despite the Europe-wide decline, no changes or increases have been observed between 2005 and 2010 in some (regions of) countries.
Afficher plus [+] Moins [-]Will technological modernization for power generation at an oil refinery diminish the risks from air pollution to the Atlantic Rainforest in Cubatão, SE Brazil?
2015
Nakazato, Ricardo K. | Rinaldi, Mirian C.S. | Domingos, Marisa
We assessed the level of atmospheric contamination by S, N and metals before, during and after the installation of a new thermoelectric plant that provides power to an oil refinery in Cubatão, SE Brazil. We measured the foliar accumulation in Lolium multiflorum “Lema” with the aim of evaluating risks to the Atlantic Rainforest that grows in the region. Al, Co, Cr, Cu, K, N, Ni, S, V and Zn were appropriate markers of the new air contamination profile associated with the modern technology. With the exception of V, the leaf contents of these elements significantly increased between the pre-operation to post-operation phases (Al, Co, N, K, S), or only during the transition phase (Zn, Cu, Cr, Ni), and returned to the previous levels after the total shutdown of the old system. Therefore, the expected environmental gain was not achieved with the installation of the new technology.
Afficher plus [+] Moins [-]Maternal exposure to alkali, alkali earth, transition and other metals: Concentrations and predictors of exposure
2015
Hinwood, A.L. | Stasinska, A. | Callan, A.C. | Heyworth, J. | Ramalingam, M. | Boyce, M. | McCafferty, P. | Odland, J.Ø
Most studies of metals exposure focus on the heavy metals. There are many other metals (the transition, alkali and alkaline earth metals in particular) in common use in electronics, defense industries, emitted via combustion and which are naturally present in the environment, that have received limited attention in terms of human exposure. We analysed samples of whole blood (172), urine (173) and drinking water (172) for antimony, beryllium, bismuth, cesium, gallium, rubidium, silver, strontium, thallium, thorium and vanadium using ICPMS. In general most metals concentrations were low and below the analytical limit of detection with some high concentrations observed. Few factors examined in regression models were shown to influence biological metals concentrations and explained little of the variation. Further study is required to establish the source of metals exposures at the high end of the ranges of concentrations measured and the potential for any adverse health impacts in children.
Afficher plus [+] Moins [-]Metals in Mediterranean aquatic species
2015
Iamiceli, AnnaLaura | Ubaldi, Alessandro | Lucchetti, Dario | Brambilla, Gianfranco | Abate, Vittorio | De Felip, Elena | De Filippis, Stefania P. | Dellatte, Elena | De Luca, Silvia | Ferri, Fabiola | Fochi, Igor | Fulgenzi, AnnaRita | Iacovella, Nicola | Moret, Ivo | Piazza, Rossano | Roncarati, Alessandra | Melotti, Paolo | Fanelli, Roberto | Fattore, Elena | Di Domenico, Alessandro | Miniero, Roberto
Metals such as arsenic (As), cadmium (Cd), copper (Cu), chromium (Cr), nickel (Ni), lead (Pb), vanadium (V), have been determined in species of Mediterranean marine organisms collected from areas supposed to be at background contamination levels. The Inductively Coupled Plasma Mass Spectrometry (ICP-MS) approach was adopted for the determination of all the metals. Arsenic, Cd and Pb determined in the 42 samples, do not exceed the pertinent maximum level except a sample of hake. In wild fish, the concentration range for Cr, Ni, V and Cu was, respectively: 0.07–0.09, 87.6–124, 0.022–0.075 and 0.79–1.74μg/g fresh weight (fw). The farmed fish samples show concentration levels below the wild fish ones, except for Cr which range at the same levels. Cadmium and Pb show a high sample number under the quantification limit. The elements do not bio-magnify among the species considered and appear to show low variations in relation to organisms’ position in the food chain and at sampling sites.
Afficher plus [+] Moins [-]Spatial distribution of some trace and major elements in sediments of the Cávado estuary (Esposende, Portugal)
2015
Gredilla, Ainara | Stoĭchev, Teodor | Fdez-Ortiz de Vallejuelo, Silvia | Rodriguez-Iruretagoiena, Azibar | de Morais, Paulo | Arana, Gorka | de Diego, Alberto | Madariaga, Juan Manuel
For the first time, the occurrence and spatial distribution of several elements, including some toxic metals, have been investigated in sediments of the estuary of the Cávado River (Esposende, Portugal). The pseudo total concentrations of Al, As, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sn, V and Zn in sediments collected at 24 sites covering the tidal part of the estuary were determined. According to the concentrations measured, the Cávado estuary can be considered as non-contaminated. For most of the elements, the concentrations tended to be higher upstream. Only a moderate enrichment in Cr and Ni was detected in a few sites. An important decrease in concentration was observed for the most toxic metals compared to historical data reported in the literature. Several hotspots were identified, but even in those cases the amount of metals stored in the sediments does not represent a toxicological threat to living organisms.
Afficher plus [+] Moins [-]Characterization and activity of N doped TiO2 supported VPO catalysts for NO oxidation
2015
Jia, Yong | Du, Daqian | Bai, Jiachuan | Ding, Jie | Zhong, Qin | Ding, Xilou
Nitrogen (N) doped TiO2 supported vanadium phosphorus oxide (VPO) catalysts were prepared and tested for catalytic oxidation of NO. The experimental results showed that 0.1V(5)PO/TiN(1) was the optimal catalyst for NO oxidation and the NO conversion could reach 61% at temperature of 350°C. The physico–chemical properties of 0.1V(5)PO/TiN(1) catalyst were characterized by Brunauer–Emmett–Teller measurements (BET), Photoluminescence (PL), X–ray photoelectron spectroscopy (XPS), Infrared spectroscopy measurements of NH3 adsorbed on catalysts (NH3–IR), and Infrared Fourier transform spectroscopy (FTIR). The PL and XPS spectra revealed that the oxygen storage capacity and catalytic activity of VPO/Ti catalyst can be improved by nitrogen doping. The H2–TPR profile also indicated that V(5)PO/TiN(1) catalyst had a superior redox property. Activity test results and FTIR spectra showed that 0.1V(5)PO/TiN(1) catalysts had a superior resistivity to SO2 and the NO oxidation rate is above 50% at temperature of 350°C when SO2 concentration is 200ppm to 800ppm.
Afficher plus [+] Moins [-]Weak acid extractable metals in Bramble Bay, Queensland, Australia: Temporal behaviour, enrichment and source apportionment
2015
Brady, James P. | Ayoko, G. A. (Godwin A.) | Martens, Wayde N. | Goonetilleke, Ashantha
Sediment samples were taken from six sampling sites in Bramble Bay, Queensland, Australia between February and November in 2012. They were analysed for a range of heavy metals including Al, Fe, Mn, Ti, Ce, Th, U, V, Cr, Co, Ni, Cu, Zn, As, Cd, Sb, Te, Hg, Tl and Pb. Fraction analysis, Enrichment Factors and Principal Component Analysis–Absolute Principal Component Scores (PCA–APCS) were carried out in order to assess metal pollution, potential bioavailability and source apportionment. Cr and Ni exceeded the Australian Interim Sediment Quality Guidelines at some sampling sites, while Hg was found to be the most enriched metal. Fraction analysis identified increased weak acid soluble Hg and Cd during the sampling period. Source apportionment via PCA–APCS found four sources of metals pollution, namely, marine sediments, shipping, antifouling coatings and a mixed source. These sources need to be considered in any metal pollution control measure within Bramble Bay.
Afficher plus [+] Moins [-]Elemental composition of two ecologically contrasting seamount fishes, the bluemouth (Helicolenus dactylopterus) and blackspot seabream (Pagellus bogaraveo)
2015
Raimundo, Joana | Vale, Carlos | Martins, Inês | Fontes, Jorge | Graça, Gonçalo | Caetano, Miguel
Concentrations of V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Cd and Pb were determined in muscle, liver and gonads of two ecologically contrasting fishes, Helicolenus dactylopterus (benthic) and Pagellus bogaraveo (benthopelagic). Elevated concentrations of As, Se and Cd found in tissues of both species appear to mirror the contribution of volcanic activity to the natural inputs of elements to Azorean waters. Results showed different element accumulation between the two species. Whereas higher concentrations were found in the liver of P. bogaraveo, elevated values were observed in the muscle of H. dactylopterus. Differences in accumulation are most likely related to metabolic rates, diet specificities and habitat. Concentrations in gonads varied up to four orders of magnitude, being higher and more variable in P. bogaraveo than H. dactylopterus. Elevated values of Cd were detected in gonads of both species despite its non-essential role on metabolic functions, presumably related to elimination.
Afficher plus [+] Moins [-]The composition of PM1 and PM2.5 samples, metals and their water soluble fractions in the Bologna area (Italy)
2015
Sarti, Elena | Pasti, Luisa | Rossi, Mauro | Ascanelli, Monica | Pagnoni, Antonella | Trombini, Monica | Remelli, Maurizio
In this study the metal composition of PM1 and PM2.5 samples collected in the surroundings of a municipal incinerator located in a suburban–farming area, less than 10 km away from Northeast of Bologna (Italy) was investigated. Seven out of eight monitoring stations were installed in a domain of 8x9 km2 around the incinerator plant; the eighth station was placed inside the urban area of Bologna. The coordinates of four monitoring stations were selected on the basis of a preliminary study by using a dispersion model. Eleven metals (Al, Sb, As, Cd, Fe, Mn, Ni, Pb, Cu, V, Zn) were quantified in both the filter acid–digests and in the water extracts. The PM2.5 collected in all the sites of the domain were highly correlated with exception of the urban site. The daily average metal concentrations in summer were 1.84% and 1.14% for PM2.5 and PM1 respectively, indicating that fine particles are less enriched in metals. Fe, Al and Zn were the most abundant elements, and they represented about the 80% of the total amount of the analyzed ones. The average water soluble metal compositions were 0.71% and 0.41% for PM2.5 and PM1 respectively. In the sites of the suburban–farming studied area the Principal Component Analysis (PCA) and Cluster Analysis revealed differences between water soluble metal compositions in PM1 and PM2.5. The urban sites were characterized by lower total and soluble metals contents than the other PM2.5 stations installed around the incinerator plant. However, no noticeable difference in the concentrations of metals in the particulate matter between the sites chosen as maxima of incinerator emissions and the control sites was observed.
Afficher plus [+] Moins [-]Heavy metal pollution assessment in relation to sediment properties in the coastal sediments of the southern Caspian Sea
2015
Bastami, Kazem Darvish | Neyestani, Mahmoud Reza | Shemirani, Farzaneh | Soltani, Farzaneh | Haghparast, Sarah | Akbari, Atefeh
This study aimed to evaluate major elements and heavy metal concentrations of Arsenic (As), Copper (Cu), Chromium (Cr), Cobalt (Co), Vanadium (V), Nickel (Ni), lead (Pb) and Zinc (Zn) in surface sediments of the southern Caspian Sea. Metal contents in the sediment were observed in the order of: V>Cr>Zn>Ni>Co>Cu>Pb>As. Correlations between elements showed that sediment TOM, grain size and chemical composition are the main factors that influence the distribution of heavy metals. According to the pollution load index (PLI), sediments from some sampling sites were polluted. Concentrations of Ni, As, Cr and Cu were higher than sediment quality guidelines at some sampling sites, implying potential adverse impacts of these metals.
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