خيارات البحث
النتائج 291 - 300 من 1,956
Modelling relationships between lichen bioindicators, air quality and climate on a national scale: Results from the UK OPAL air survey النص الكامل
2013
Seed, Lindsay | Wolseley, P. A. | Gosling, Laura | Davies, Linda | Power, Sally A.
Air pollution has many negative effects on the natural environment, from changes in plant growth patterns to loss of ecosystem function. This study uses citizen science to investigate national-scale patterns in the distribution and abundance of selected lichen species on tree trunks and branches, and to relate these to air pollution and climate. Volunteers collected data for nine lichen indicators on 19,334 deciduous trees. Submitted data provided information on species-level patterns, and were used to derive composite lichen indices. Multiple linear regression and ANCOVA were used to model the relationships between lichen response variables on Quercus spp. and pollution, climate and location. The study demonstrated significant relationships between patterns in indicator lichens and levels of N- and S-containing pollutants on trunks and twigs. The derived lichen indices show great potential as a tool to provide information on local, site-specific levels of air quality.
اظهر المزيد [+] اقل [-]Toxicity testing of dispersed oil requires adherence to standardized protocols to assess potential real world effects النص الكامل
2013
Coelho, Gina | Clark, James | Aurand, Don
Recently, several researchers have attempted to address Deepwater Horizon incident environmental fate and effects issues using laboratory testing and extrapolation procedures that are not fully reliable measures for environmental assessments. The 2013 Rico-Martínez et al. publication utilized laboratory testing approaches that severely limit our ability to reliably extrapolate such results to meaningful real-world assessments.The authors did not adopt key methodological elements of oil and dispersed oil toxicity standards. Further, they drew real-world conclusions from static exposure tests without reporting actual exposure concentrations. Without this information, it is not possible to compare their results to other research or real spill events that measured and reported exposure concentrations.The 1990s' Chemical Response to Oil Spills: Ecological Effects Research Forum program was established to standardize and conduct exposure characterization in oil and dispersed oil aquatic toxicity testing (Aurand and Coelho, 2005). This commentary raises awareness regarding the necessity of standardized test protocols.
اظهر المزيد [+] اقل [-]Dechlorane Plus flame retardant in terrestrial raptors from northern China النص الكامل
2013
Chen, Da | Wang, Yan | Yu, Lehuan | Luo, Xiaojun | Mai, Bixian | Li, Shaoshan
While a number of studies have addressed the environmental presence and behavior of the Dechlorane Plus (DP) flame retardant, there is still a dearth of information in terrestrial ecosystems. The present study revealed that median ∑DP (including anti- and syn-DP isomers) concentrations ranged from 10 to 810 ng/g lipid weight in muscle and liver tissues of six terrestrial raptor species collected in 2004–2006 from Beijing, China. Some concentrations rival the greatest DP burdens ever reported in global wildlife. Significant, positive correlations were observed between fanti (concentration ratio of anti-isomer to ∑DP) and ∑DP concentrations in the Eurasian sparrowhawk (Accipiter nisus) tissues. These results suggested that the DP burdens could be substantially driven by the accumulation of the anti-isomer in terrestrial birds. The tissue-specific accumulation of DP further suggested that factors (e.g., hepatic binding enzymes) other than lipid solubility could be important in determining tissue deposition of DP.
اظهر المزيد [+] اقل [-]Modelling mercury concentrations in prey fish: Derivation of a national-scale common indicator of dietary mercury exposure for piscivorous fish and wildlife النص الكامل
2013
Depew, David C. | Burgess, Neil M. | Campbell, Linda M.
The National Descriptive Model for Mercury in Fish (NDMMF) was applied to a Canada – wide dataset of fish mercury (Hg) concentrations to derive a common indicator of dietary methylmercury (MeHg) exposure (HgPREY) to piscivorous fish and wildlife. The NDMMF provided unbiased parameter estimates and strong spatial biases in prediction error were not apparent. Prediction error was comparatively higher when sample sizes were small and events with high Hg concentrations. Estimates of HgPREY from 1936 locations between 1990 and 2010 averaged 0.09 ± 0.07 μg g−1 (wet wt) and increased from west to east in a manner consistent with independent measures of MeHg exposure in piscivorous wildlife and conceptual models of aquatic ecosystem sensitivity to Hg methylation and bioaccumulation. The HgPREY dataset offers an approach to evaluate the risk of MeHg exposure to piscivorous fish and wildlife on a continental scale.
اظهر المزيد [+] اقل [-]Assessing ecotoxicity and uptake of metals and metalloids in relation to two different earthworm species (Eiseina hortensis and Lumbricus terrestris) النص الكامل
2013
Leveque, Thibaut | Capowiez, Yvan | Schreck, Eva | Mazzia, Christophe | Auffan, Mélanie | Foucault, Yann | Austruy, Annabelle | Dumat, Camille
Assessing ecotoxicity and uptake of metals and metalloids in relation to two different earthworm species (Eiseina hortensis and Lumbricus terrestris) النص الكامل
2013
Leveque, Thibaut | Capowiez, Yvan | Schreck, Eva | Mazzia, Christophe | Auffan, Mélanie | Foucault, Yann | Austruy, Annabelle | Dumat, Camille
Due to diffuse atmospheric fallouts of process particles enriched by metals and metalloids, polluted soils concern large areas at the global scale. Useful tools to assess ecotoxicity induced by these polluted soils are therefore needed. Earthworms are currently used as biotest, however the influence of specie and earthworm behaviour, soil characteristics are poorly highlighted. Our aim was therefore to assess the toxicity of various polluted soils with process particles enriches by metals and metalloids (Pb, Cd, Cu, Zn, As and Sb) collected from a lead recycling facility on two earthworm species belonging to different ecological types and thus likely to have contrasted behavioural responses (Eiseina hortensis and Lumbricus terrestris).The combination of behavioural factors measurements (cast production and biomass) and physico-chemical parameters such as metal absorption, bioaccumulation by earthworms and their localization in invertebrate tissues provided a valuable indication of pollutant bioavailability and ecotoxicity. Soil characteristics influenced ecotoxicity and metal uptake by earthworms, as well as their soil bioturbation.
اظهر المزيد [+] اقل [-]Assessing ecotoxicity and uptake of metals and metalloids in relation to two different earthworm species (Eiseina horterzsis and Lumbricus terrestris) النص الكامل
2013
Leveque, Thibaut | Capowiez, Yvan | Schreck, Eva | Mazzia, Christophe | Auffan, Mélanie | Foucault, Yann | Austruy, Annabelle
Due to diffuse atmospheric fallouts of process particles enriched by metals and metalloids, polluted soils concern large areas at the global scale. Useful tools to assess ecotoxicity induced by these polluted soils are therefore needed. Earthworms are currently used as biotest, however the influence of specie and earthworm behaviour, soil characteristics are poorly highlighted. Our aim was therefore to assess the toxicity of various polluted soils with process particles enriches by metals and metalloids (Pb, Cd, Cu, Zn, As and Sb) collected from a lead recycling facility on two earthworm species belonging to different ecological types and thus likely to have contrasted behavioural responses (Eiseina hortensis and Lumbricus terrestris). The combination of behavioural factors measurements (cast production and biomass) and physicochemical parameters such as metal absorption, bioaccumulation by earthworms and their localization in invertebrate tissues provided a valuable indication of pollutant bioavailability and ecotoxicity. Soil characteristics influenced ecotoxicity and metal uptake by earthworms, as well as their soil bioturbation.
اظهر المزيد [+] اقل [-]Assessing ecotoxicity and uptake of metals and metalloids in relation to two different earthworm species (Eiseina hortensis and Lumbricus terrestris) النص الكامل
2013
Lévèque, Thibaut | Capowiez, Yvan | Schreck, Eva | Mazzia, Christophe | Auffan, Melanie | Foucault, Yann | Austruy, Annabelle | Dumat, Camille | École nationale supérieure agronomique de Toulouse (ENSAT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT) | Laboratoire Ecologie Fonctionnelle et Environnement (LEFE) ; Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT) | Unité de recherche Plantes et Systèmes de Culture Horticoles (PSH) ; Institut National de la Recherche Agronomique (INRA) | Géosciences Environnement Toulouse (GET) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS) | Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE) ; Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS) | Abeilles et Environnement (AE) ; Institut National de la Recherche Agronomique (INRA)-Avignon Université (AU) | Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement (CEREGE) ; Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Société de Traitements Chimiques des Métaux (STCM) ; Toulouse | Centre d'Etude et de Recherche Travail Organisation Pouvoir (CERTOP) ; Université Toulouse - Jean Jaurès (UT2J) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS) | ANR-11-LABX-0066,SMS/SSW,Structurations des mondes sociaux(2011)
International audience | Due to diffuse atmospheric fallouts of process particles enriched by metals and metalloids, polluted soils concern large areas at the global scale. Useful tools to assess ecotoxicity induced by these polluted soils are therefore needed. Earthworms are currently used as biotest, however the influence of specie and earthworm behaviour, soil characteristics are poorly highlighted. Our aim was therefore to assess the toxicity of various polluted soils with process particles enriches by metals and metalloids (Pb, Cd, Cu, Zn, As and Sb) collected from a lead recycling facility on two earthworm species belonging to different ecological types and thus likely to have contrasted behavioural responses (Eiseina hortensis and Lum-bricus terrestris). The combination of behavioural factors measurements (cast production and biomass) and physico-chemical parameters such as metal absorption, bioaccumulation by earthworms and their localization in invertebrate tissues provided a valuable indication of pollutant bioavailability and ecotoxicity. Soil characteristics influenced ecotoxicity and metal uptake by earthworms, as well as their soil bioturbation.
اظهر المزيد [+] اقل [-]Assessing ecotoxicity and uptake of metals and metalloids in relation to two different earthworm species (Eiseina horterzsis and Lumbricus terrestris) النص الكامل
2013
Leveque , Thibaut (Université de ToulouseEcolab Laboratoire d'écologie fonctionnelle, Castanet-Tolosan31326 Castanet-Tolosan (France). INP-ENSATUMR 5245 CNRS-INP-UPS) | Capowiez , Yvan (INRA , Avignon (France). UR 1115 Unité de recherche Plantes et Systèmes de Culture Horticoles) | Schreck , Eva (Géosciences Environnement Toulouse, Toulouse(France). UMR 5563 CNRS/UPS/IRD/CNES) | Mazzia , Christophe (Institut Méditerranéen de Biodiversité et d'Écologie Marine et Continentale(France). UMR CNRS 7263) | Auffan , Mélanie (Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement, Aix-en-Provence(France). Europôle méditerranéen de l’Arbois) | Foucault , Yann (Université de ToulouseEcolab Laboratoire d'écologie fonctionnelleSociété de Traitement Chimique des Métaux, Castanet-Tolosan31326 Castanet-Tolosan Toulouse(France). INP-ENSATUMR 5245 CNRS-INP-UPS) | Austruy , Annabelle (Université de ToulouseEcolab Laboratoire d'écologie fonctionnelle, Castanet-Tolosan31326 Castanet-Tolosan (France). INP-ENSATUMR 5245 CNRS-INP-UPS) | Dumat , Camille (auteur de correspondance) (Université de ToulouseEcolab Laboratoire d'écologie fonctionnelle, Castanet-Tolosan31326 Castanet-Tolosan (France). INP-ENSATUMR 5245 CNRS-INP-UPS)
Due to diffuse atmospheric fallouts of process particles enriched by metals and metalloids, polluted soils concern large areas at the global scale. Useful tools to assess ecotoxicity induced by these polluted soils are therefore needed. Earthworms are currently used as biotest, however the influence of specie and earthworm behaviour, soil characteristics are poorly highlighted. Our aim was therefore to assess the toxicity of various polluted soils with process particles enriches by metals and metalloids (Pb, Cd, Cu, Zn, As and Sb) collected from a lead recycling facility on two earthworm species belonging to different ecological types and thus likely to have contrasted behavioural responses (Eiseina hortensis and Lumbricus terrestris). The combination of behavioural factors measurements (cast production and biomass) and physicochemical parameters such as metal absorption, bioaccumulation by earthworms and their localization in invertebrate tissues provided a valuable indication of pollutant bioavailability and ecotoxicity. Soil characteristics influenced ecotoxicity and metal uptake by earthworms, as well as their soil bioturbation.
اظهر المزيد [+] اقل [-]Pb and Zn imaging and in situ speciation at the geogenic/biogenic interface in sentinel earthworms using electron microprobe and synchrotron micro-focus X-ray spectroscopy النص الكامل
2013
Morgan, A.J. | Kille, P. | Bennett, A. | O'Reilly, M. | Fisher, P. | Charnock, J.M.
Using synchrotron- and electron microscope-based X-ray microanalyses, the distribution and speciation of Zn and Pb were examined in situ in two earthworm species (Dendrodrilus rubidus and Lumbricus rubellus) living in heavily-polluted soils. Main findings: (i) Zn spectra in ingested soil and in tissues more closely resembled Zn3(PO4)2 than ZnS; (ii) Zn speciation in tissues gave a best fit for Zn to the inner shell of 4 oxygens at 1.94 Å (or nitrogens at 1.96 Å); (iii) the best fit for Pb in tissue was with a shell of oxygens at 2.18 Å and a shell of sulphurs at 2.67 Å; (iv) a component of the Zn and much of the Pb detectable in gut contents was co-distributed with S; (v) Zn and Pb display ‘soft’ acid affinities in soil, but ‘hard’ acid affinities in tissue. This is the first metal characterisation study conducted on an invertebrate quench-frozen in the field.
اظهر المزيد [+] اقل [-]Effects of water chemistry on the dissolution of ZnO nanoparticles and their toxicity to Escherichia coli النص الكامل
2013
Li, Mei | Lin, Daohui | Zhu, Lizhong
The dissolution of ZnO nanoparticles (nano-ZnO) plays an important role in the toxicity of nano-ZnO to the aquatic organisms. The effects of water chemistry such as pH, ionic components, and dissolved organic matter (DOM) on the dissolution of nano-ZnO and its toxicity to Escherichia coli (E. coli) were investigated in synthetic and natural water samples. The results showed that the toxicity of nano-ZnO to E. coli depended on not only free Zn2+ but also the coexisting cations which could reduce the toxicity of Zn2+. Increasing solution pH, HPO42−, and DOM reduced the concentration of free Zn2+ released from nano-ZnO, and thus lowered the toxicity of nano-ZnO. In addition, both Ca2+ and Mg2+ dramatically reduced the toxicity of Zn2+ to E. coli. These results highlight the importance of water chemistry on the toxicity evaluation of nano-ZnO in natural waters.
اظهر المزيد [+] اقل [-]Comparison of extended-spectrum-β-lactamase (ESBL) carrying Escherichia coli from sewage sludge and human urinary tract infection النص الكامل
2013
Zarfel, G. | Galler, H. | Feierl, G. | Haas, D. | Kittinger, C. | Leitner, E. | Grisold, A.J. | Mascher, F. | Posch, J. | Pertschy, B. | Marth, E. | Reinthaler, F.F.
For many years, extended-spectrum-beta-lactamase (ESBL) producing bacteria were a problem mainly located in medical facilities. Within the last decade however, ESBL-producing bacteria have started spreading into the community and the environment. In this study, ESBL-producing Escherichia coli from sewage sludge were collected, analysed and compared to ESBL-E. coli from human urinary tract infections (UTIs). The dominant ESBL-gene-family in both sample groups was blaCTX-M, which is the most prevalent ESBL-gene-family in human infection. Still, the distribution of ESBL genes and the frequency of additional antibiotic resistances differed in the two sample sets. Nevertheless, phenotyping did not divide isolates of the two sources into separate groups, suggesting similar strains in both sample sets. We speculate that an exchange is taking place between the ESBL E. coli populations in infected humans and sewage sludge, most likely by the entry of ESBL E. coli from UTIs into the sewage system.
اظهر المزيد [+] اقل [-]Passive sampling of perfluorinated chemicals in water: Flow rate effects on chemical uptake النص الكامل
2013
Kaserzon, Sarit L. | Vermeirssen, Etiënne L.M. | Hawker, Darryl W. | Kennedy, Karen | Bentley, Christie | Thompson, Jack | Booij, Kees | Mueller, Jochen F.
A recently developed modified polar organic chemical integrative sampler (POCIS) provides a means for monitoring perfluorinated chemicals (PFCs) in water. However, changes in external flow rates may alter POCIS sampling behaviour and consequently affect estimated water concentrations of analytes. In this work, uptake kinetics of selected PFCs, over 15 days, were investigated. A flow-through channel system was employed with spiked river water at flow rates between 0.02 and 0.34 m s−1. PFC sampling rates (Rs) (0.09–0.29 L d−1 depending on analyte and flow rate) increased from the lowest to highest flow rate employed for some PFCs (MW ≤ 464) but not for others (MW ≥ 500). Rs's for some of these smaller PFCs were increasingly less sensitive to flow rate as this increased within the range investigated. This device shows promise as a sampling tool to support monitoring efforts for PFCs in a range of flow rate conditions.
اظهر المزيد [+] اقل [-]Assessment of flame retardants in river water using a ceramic dosimeter passive sampler النص الكامل
2013
Cristale, Joyce | Katsoyiannis, Athanasios | Chen, Chang'er | Jones, K. C. (Kevin C.) | Lacorte, Silvia
Novel brominated (BFRs) and organophosphorus (OPFRs) flame retardants were monitored in river water using the ceramic dosimeter passive sampling device with HLB (hydrophilic–lipophilic balance) as sorbent. Laboratory calibrations were performed to determine sampling rates for each compound using the Archie's law exponent. The passive sampling device was used to determine the presence of 6 BFRs in the River Aire (United Kingdom), selected according to their ubiquitous presence in the River Aire. Passive sampling integrated river water concentrations ranged from 0.010 to 5.6 μg L−1 for all OPFRs, while BFRs were not detected with this specific passive sampler configuration. Decreased sampling rates were evidenced after 3 weeks of deployment, probably due to fouling. Good agreement between integrated and snapshot water concentrations was obtained, indicating the efficiency of the passive sampler for the monitoring of OPFRs in river water.
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