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Assessing the genotoxicity of urban air pollutants using two in situ plant bioassays
2009
Villarini, M. | Fatigoni, C. | Dominici, L. | Maestri, S. | Ederli, L. | Pasqualini, S. | Monarca, S. | Moretti, M.
Genotoxicity of urban air has been analysed almost exclusively in airborne particulates. We monitored the genotoxic effects of airborne pollutants in the urban air of Perugia (Central Italy). Two plant bioindicators with different genetic endpoints were used: micronuclei in meiotic pollen mother cells using Tradescantia-micronucleus bioassay (Trad-MCN) and DNA damage in nuclei of Nicotiana tabacum leaves using comet assay (Nicotiana-comet). Buds of Tradescantia clone # 4430 and young N. tabacum cv. Xanthi plants were exposed for 24 h at three sites with different pollution levels. One control site (indoor control) was also used. The two bioassays showed different sensitivities toward urban pollutants: Trad-MCN assay was the most sensitive, but DNA damage in N. tabacum showed a better correlation with the pollutant concentrations. In situ biomonitoring of airborne genotoxins using higher plants combined with chemical analysis is thus recommended for characterizing genotoxicity of urban air. Plant bioassays used to explore in situ the correlation between air pollution and genotoxicity.
显示更多 [+] 显示较少 [-]Environmental-geochemical characteristics of Cu in the soil and water in copper-rich deposit area of southeastern Hubei Province, along the middle Yangtze River, Central China
2009
Zhang, Ling | Wang, Lu | Yin, Kedong | Lv, Ying | Zhang, Derong
In this study, the natural Cu background concentration and Cu natural and anthropogenic contamination in soil, water and crop were investigated systematically in Huangshi area. The results show that regional geology is the dominant factor controlling the natural Cu background concentration in soil and water, and that pH is important to control the vertical distribution of Cu in soil under the same geographical and climatic conditions. The mineralization of rock bodies causes the natural Cu increase in soil and water, whereas, a large number of mining-smelting plants and chemical works are the main sources of Cu anthropogenic contamination. Cu in naturally and anthropogenically polluted soil displays differences in total and available contents, vertical distribution patterns and physico-chemical properties, the same happens in water. Consider the rock-soil-water-crop as a system to study the geochemical activities and environmental pollution of copper.
显示更多 [+] 显示较少 [-]Impact of the Phaeocystis globosa spring bloom on the intertidal benthic compartment in the eastern English Channel: A synthesis
2009
Spilmont, Nicolas | Denis, Lucie | Artigas, Luis Felipe | Caloin, Frederic | Courcot, Lucie | Creach, Anne | Desroy, Nicolas | Gevaert, Francois | Hacquebart, Pascal | Hubas, Cedric | Janquin, Marie-andree | Lemoine, Yves | Luczak, Christophe | Migne, Aline | Rauch, Mathieu | Davoult, Dominique
From 1999 to 2005, studies carried out in the frame of regional and national French programs aimed to determine whether the Phaeocystis globosa bloom affected the intertidal benthic communities of the French coast of the eastern English Channel in terms of composition and/or functioning. Study sites were chosen to cover most of the typical shore types encountered on this coast (a rocky shore, an exposed sandy beach and a small estuary). Both the presence of active Phaeocystis cells and their degradation product (foam) did have a significant impact on the studied shores. The primary production and growth rates of the kelp Saccharina latissima decreased during the bloom because of a shortage of fight and nutrient for the macroalgae. On sandy sediments, the benthic metabolism (community respiration and community primary production), as well as the nitrification rate, were enhanced during foam deposits, in relation with the presence of bacteria and active pelagic cells within the decaying colonies. In estuarine sediments, the most impressive impact was the formation of a crust at the sediment surface due to drying foam. This led to anoxic conditions in the surface sediment and resulted in a high mortality among the benthic community. Some organisms also tended to migrate upward and were then directly accessible to the higher trophic level represented by birds. Phaeocystis then created a shortcut in the estuarine trophic network. Most of these modifications lasted shortly and all the systems considered came back to their regular properties and activities a few weeks after the end of the bloom, except for the most impacted estuarine area. (C) 2008 Elsevier Ltd. All rights reserved.
显示更多 [+] 显示较少 [-]Outlier identification and visualization for Pb concentrations in urban soils and its implications for identification of potential contaminated land
2009
Zhang, Chaosheng | Tang, Ya | Luo, Lin | Xu, Weilin
Outliers in urban soil geochemical databases may imply potential contaminated land. Different methodologies which can be easily implemented for the identification of global and spatial outliers were applied for Pb concentrations in urban soils of Galway City in Ireland. Due to its strongly skewed probability feature, a Box-Cox transformation was performed prior to further analyses. The graphic methods of histogram and box-and-whisker plot were effective in identification of global outliers at the original scale of the dataset. Spatial outliers could be identified by a local indicator of spatial association of local Moran's I, cross-validation of kriging, and a geographically weighted regression. The spatial locations of outliers were visualised using a geographical information system. Different methods showed generally consistent results, but differences existed. It is suggested that outliers identified by statistical methods should be confirmed and justified using scientific knowledge before they are properly dealt with. Outliers in urban geochemical databases can be detected to provide guidance for identification of potential contaminated land.
显示更多 [+] 显示较少 [-]Bioaccumulation of glyphosate and its formulation Roundup Ultra in Lumbriculus variegatus and its effects on biotransformation and antioxidant enzymes
2009
Contardo-Jara, Valeska | Klingelmann, Eva | Wiegand, Claudia
The bioaccumulation potential of glyphosate and the formulation Roundup Ultra, as well as possible effects on biotransformation and antioxidant enzymes in Lumbriculus variegatus were compared by four days exposure to concentrations between 0.05 and 5 mg L-1 pure glyphosate and its formulation. Bioaccumulation was determined using 14C labeled glyphosate. The bioaccumulation factor (BCF) varied between 1.4 and 5.9 for the different concentrations, and was higher than estimated from log Pow. Glyphosate and its surfactant POEA caused elevation of biotransformation enzyme soluble glutathione S-transferase at non-toxic concentrations. Membrane bound glutathione S-transferase activity was significantly elevated in Roundup Ultra exposed worms, compared to treatment with equal glyphosate concentrations, but did not significantly differ from the control. Antioxidant enzyme superoxide dismutase was significantly increased by glyphosate but in particular by Roundup Ultra exposure indicating oxidative stress. The results show that the formulation Roundup Ultra is of more ecotoxicological relevance than the glyphosate itself. Roundup Ultra is of more ecotoxicological relevance than the active ingredient, glyphosate, to Lumbriculus variegatus regarding accumulation potential and enzymatic responses.
显示更多 [+] 显示较少 [-]Pine weevil feeding on Norway spruce bark has a stronger impact on needle VOC emissions than enhanced ultraviolet-B radiation
2009
Blande, James D. | Turunen, Katariina | Holopainen, Jarmo K.
Plants can respond physiologically to damaging ultraviolet-B radiation by altering leaf chemistry, especially UV absorbing phenolic compounds. However, the effects on terpene emissions have received little attention. We conducted two field trials in plots with supplemented UV-B radiation and assessed the influence of feeding by pine weevils, Hylobius abietis L., on volatile emissions from 3-year old Norway spruce trees (Picea abies L. Karst.). We collected emissions from branch tips distal to the feeding weevils, and from whole branches including the damage sites. Weevil feeding clearly induced the emission of monoterpenes and sesquiterpenes, particularly linalool and (E)-β-farnesene, from branch tips, and the sums of monoterpenes and sesquiterpenes emitted by whole branches were substantially increased. We discovered little effect of UV-B radiation up to 30% above the ambient level on volatile emissions from branch tips distal to damage sites, but there was a possible effect on bark emissions from damage sites. Chronic exposure to enhanced UV-B radiation has little effect on volatile emissions of Norway spruce.
显示更多 [+] 显示较少 [-]Highly charged swelling mica reduces Cu bioavailability in Cu-contaminated soils
2009
Stuckey, Jason W. | Neaman, Alexander | Ravella, Ramesh | Komarneni, Sridhar | Martínez, Carmen Enid
This is the first test of a highly charged swelling mica's (Na-2-mica) ability to reduce the plant-absorbed Cu in Cu-contaminated soils from Chile. Perennial ryegrass (Lolium perenne L.) was grown in two acid soils (Sector 2: pH 4.2, total Cu = 172 mg Cu kg-1 and Sector 3: pH 4.2, total Cu = 112 mg Cu kg-1) amended with 0.5% and 1% (w/w) mica, and 1% (w/w) montmorillonite. At 10 weeks of growth, both mica treatments decreased the shoot Cu of ryegrass grown in Sector 2 producing shoot Cu concentrations above 21-22 mg Cu kg-1 (the phytotoxicity threshold for that species), yet the mica treatments did not reduce shoot Cu concentrations when grown in Sector 3, which were at a typical level. The mica treatments improved shoot growth in Sector 3 by reducing free and extractable Cu to low enough levels where other nutrients could compete for plant absorption and translocation. In addition, the mica treatments improved root growth in both soils, and the 1% mica treatment reduced root Cu in both soils. This swelling mica warrants further testing of its ability to assist re-vegetation and reduce Cu bioavailability in Cu-contaminated surface soils. In situ remediation of Cu-contaminated soils with a synthetic mica (Na-2-mica) will aid in re-vegetative efforts.
显示更多 [+] 显示较少 [-]Organochlorine pesticide air-water exchange and bioconcentration in krill in the Ross Sea
2009
Cincinelli, Alessandra | Martellini, Tania | Del Bubba, Massimo | Lepri, Luciano | Corsolini, Simonetta | Borghesi, Nicoletta | King, Martin D. | Dickhut, Rebecca M.
Mean hexachlorobenzene (HCB) and hexachlorocyclohexane (HCH) concentrations, measured in seawater and air samples, confirmed the decline in levels of these compounds in Antarctic air and water. However, low α/γ-HCH ratios in air at the beginning of the sampling period suggest a predominance of fresh lindane entering the Antarctic atmosphere during the Austral spring probably due to current use in the Southern Hemisphere. Water-air fugacity ratios demonstrate the potential for HCH gas deposition to coastal Antarctic seas, while the water-air fugacity ratios for HCB imply that volatilization does not account for the observed decrease of HCB in surface seawater. HCH concentrations found in krill samples were correlated with seawater concentrations indicative of bioconcentration of HCHs from seawater. Hexachlorocyclohexanes (HCHs) continue to decline in Antarctic air, but fugacity ratios demonstrate that Antarctic coastal waters remain a sink for HCHs, which bioconcentrate in krill via direct uptake from water.
显示更多 [+] 显示较少 [-]Arsenic mobility in brownfield soils amended with green waste compost or biochar and planted with Miscanthus
2009
Hartley, William | Dickinson, Nicholas M. | Riby, Philip | Lepp, N. W. (Nicholas W)
Degraded land that is historically contaminated from different sources of industrial waste provides an opportunity for conversion to bioenergy fuel production and also to increase sequestration of carbon in soil through organic amendments. In pot experiments, As mobility was investigated in three different brownfield soils amended with green waste compost (GWC, 30% v/v) or biochar (BC, 20% v/v), planted with Miscanthus. Using GWC improved crop yield but had little effect on foliar As uptake, although the proportion of As transferred from roots to foliage differed considerably between the three soils. It also increased dissolved carbon concentrations in soil pore water that influenced Fe and As mobility. Effects of BC were less pronounced, but the impacts of both amendments on SOC, Fe, P and pH are likely to be critical in the context of As leaching to ground water. Growing Miscanthus had no measurable effect on As mobility. Green waste compost enhances water-soluble iron, phosphorus and carbon, increasing arsenic mobility in soil pore water.
显示更多 [+] 显示较少 [-]BVOC emissions, photosynthetic characteristics and changes in chloroplast ultrastructure of Platanus orientalis L. exposed to elevated CO2 and high temperature
2009
Velikova, Violeta | Tsonev, Tsonko | Barta, Csengele | Centritto, Mauro | Koleva, Dimitrina | Stefanova, Miroslava | Busheva, Mira | Loreto, Francesco
To investigate the interactive effects of increasing [CO₂] and heat wave occurrence on isoprene (IE) and methanol (ME) emissions, Platanus orientalis was grown for one month in ambient (380 mmol mol 1) or elevated (800 mmol mol 1) [CO₂] and exposed to high temperature (HT) (38 C/4 h). In pre-existing leaves, IE emissions were always higher but ME emissions lower as compared to newly-emerged leaves. They were both stimulated by HT. Elevated [CO₂] significantly reduced IE in both leaf types, whereas it increased ME in newly-emerged leaves only. In newly-emerged leaves, elevated [CO₂] decreased photosynthesis and altered the chloroplast ultrastructure and membrane integrity. These harmful effects were amplified by HT. HT did not cause any unfavorable effects in pre-existing leaves, which were characterized by inherently higher IE rates. We conclude that: (1) these results further prove the isoprene's putative thermo-protective role of membranes; (2) HT may likely outweigh the inhibitory effects of elevated [CO₂] on IE in the future.
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