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First detection of an NSAID, flunixin, in sheep’s wool using GC–MS Texto completo
2011
Richards, Ngaio | Hall, Sarah | Scott, Karen | Harrison, Nancy
Exposure to the nonsteroidal anti-inflammatory drug (NSAID) diclofenac resulted in the near extinction of three species of Gyps vultures on the Indian subcontinent. Other NSAIDs present in the environment, including flunixin, may pose a similar risk. In the course of a study to determine the feasibility of detecting NSAIDs in keratinous matrices (i.e., hair, nails and feathers) using GC–MS, wool opportunistically collected from a sheep treated with flunixin was analysed for residues. Flunixin was detected qualitatively in external wool wash and extract samples. While residues of veterinary agents and pesticides have previously been found in sheep’s wool, our preliminary investigation provides the first instance of an NSAID being detected in this matrix. Here we provide the sample preparation methods and GC–MS parameters used to enable further refinement as part of ongoing conservation and consumer quality control measures.
Mostrar más [+] Menos [-]2,4,6-Trinitrotoluene mineralization and bacterial production rates of natural microbial assemblages from coastal sediments Texto completo
2011
Montgomery, Michael T. | Coffin, Richard B. | Boyd, Thomas J. | Smith, Joseph P. | Walker, Shelby E. | Osburn, Christopher L.
The nitrogenous energetic constituent, 2,4,6-Trinitrotoluene (TNT), is widely reported to be resistant to bacterial mineralization (conversion to CO₂); however, these studies primarily involve bacterial isolates from freshwater where bacterial production is typically limited by phosphorus. This study involved six surveys of coastal waters adjacent to three biome types: temperate broadleaf, northern coniferous, and tropical. Capacity to catabolize and mineralize TNT ring carbon to CO₂ was a common feature of natural sediment assemblages from these coastal environments (ranging to 270+/−38 μg C kg⁻¹ d⁻¹). More importantly, these mineralization rates comprised a significant proportion of total heterotrophic production. The finding that most natural assemblages surveyed from these ecosystems can mineralize TNT ring carbon to CO₂ is consistent with recent reports that assemblage components can incorporate TNT ring carbon into bacterial biomass. These data counter the widely held contention that TNT is recalcitrant to bacterial catabolism of the ring carbon in natural environments.
Mostrar más [+] Menos [-]XAFS study of starch-stabilized magnetite nanoparticles and surface speciation of arsenate Texto completo
2011
Zhang, Meiyi | Pan, Gang | Zhao, Dongye | He, Guangzhi
It has been shown that starch can effectively stabilize nanoscale magnetite particles, and starch-stabilized magnetite nanoparticles (SMNP) are promising for in situ remediation of arsenic-contaminated soils. However, a molecular level understanding has been lacking. Here, we carried out XAFS studies to bridge this knowledge gap. Fe K-edge XAFS spectra indicated that the Fe–O and Fe–Fe coordination numbers of SMNP were lower than those for bare magnetite particles, and these coordination numbers decreased with increasing starch concentration. The decrease in the average coordination number at elevated stabilizer concentration was attributed to the increase in the surface-to-volume ratio. Arsenic K-edge XAFS spectra indicated that adsorbed arsenate on SMNP consisted primarily of binuclear bidentate (BB) complexes and monodentate mononuclear (MM) complexes. More BB complexes (energetically more favorable) were observed at higher starch concentrations, indicating that SMNP not only offered greater adsorption surface area, but also stronger adsorption affinity toward arsenate.
Mostrar más [+] Menos [-]Contamination and source differentiation of Pb in park soils along an urban–rural gradient in Shanghai Texto completo
2011
Li, Hong-bo | Yu, Shen | Li, Gui-lin | Deng, Hong | Luo, Xiao-san
Urban soil Pb contamination is a great human health risk. Lead distribution and source in topsoils from 14 parks in Shanghai, China were investigated along an urban–rural gradient. Topsoils were contaminated averagely with 65 mg Pb kg⁻¹, 2.5 times higher than local soil background concentrations. HCl-extracts contained more anthropogenic Pb signatures than total sample digests as revealed by the higher ²⁰⁷/²⁰⁶Pb and ²⁰⁸/²⁰⁶Pb ratios in extracts (0.8613 ± 0.0094 and 2.1085 ± 0.0121 versus total digests 0.8575 ± 0.0098 and 2.0959 ± 0.0116). This suggests a higher sensitivity of HCl-extraction than total digestion in identifying anthropogenic Pb sources. Coal combustion emission was identified as the major anthropogenic Pb source (averagely 47%) while leaded gasoline emission contributed 12% overall. Urbanization effects were observed by total Pb content and anthropogenic Pb contribution. This study suggests that to reduce Pb contamination, Shanghai might have to change its energy composition to clean energy.
Mostrar más [+] Menos [-]Developing spatially stratified N₂O emission factors for Europe Texto completo
2011
Leip, Adrian | Busto, Mirko | Winiwarter, Wilfried
We investigate the possibility to replace the – so-called – Tier 1 IPCC approach to estimate soil N₂O emissions with stratified emissions factors that take into account both N-input and the spatial variability of the environmental conditions within the countries of the European Union, using the DNDC-Europe model. Spatial variability in model simulations is high and corresponds to the variability reported in literature for field data. Our results indicate that (a) much of the observed variability in N₂O fluxes reflects the response of soils to external conditions, (b) it is likely that national inventories tend to overestimate the uncertainties in their estimated direct N₂O emissions from arable soils; (c) on average over Europe, the fertilizer-induced emissions (FIE) coincide with the IPCC factors, but they display large spatial variations. Therefore, at scales of individual countries or smaller, a stratified approach considering fertilizer type, soil characteristics and climatic parameters is preferable.
Mostrar más [+] Menos [-]Sensitivity analysis for models of greenhouse gas emissions at farm level. Case study of N₂O emissions simulated by the CERES-EGC model Texto completo
2011
Drouet, J.-L. | Capian, N. | Fiorelli, J.-L. | Blanfort, V. | Capitaine, M. | Duretz, S. | Gabrielle, B. | Martin, R. | Lardy, R. | Cellier, P. | Soussana, J.-F.
Sensitivity analysis for models of greenhouse gas emissions at farm level. Case study of N₂O emissions simulated by the CERES-EGC model Texto completo
2011
Drouet, J.-L. | Capian, N. | Fiorelli, J.-L. | Blanfort, V. | Capitaine, M. | Duretz, S. | Gabrielle, B. | Martin, R. | Lardy, R. | Cellier, P. | Soussana, J.-F.
Modelling complex systems such as farms often requires quantification of a large number of input factors. Sensitivity analyses are useful to reduce the number of input factors that are required to be measured or estimated accurately. Three methods of sensitivity analysis (the Morris method, the rank regression and correlation method and the Extended Fourier Amplitude Sensitivity Test method) were compared in the case of the CERES-EGC model applied to crops of a dairy farm. The qualitative Morris method provided a screening of the input factors. The two other quantitative methods were used to investigate more thoroughly the effects of input factors on output variables. Despite differences in terms of concepts and assumptions, the three methods provided similar results. Among the 44 factors under study, N₂O emissions were mainly sensitive to the fraction of N₂O emitted during denitrification, the maximum rate of nitrification, the soil bulk density and the cropland area.
Mostrar más [+] Menos [-]Sensitivity analysis for models of greenhouse gas emissions at farm level. Case study of N2O emissions simulated by the CERES-EGC model Texto completo
2011
Drouet, Jean-Louis | Capian, Nicolas, N. | Fiorelli, Jean-Louis, J.-L. | Blanfort, Vincent, V. | Capitaine, Mathieu | Duretz, Sylvia, S. | Gabrielle, Benoit | Martin, Raphaël | Lardy, Romain | Cellier, Pierre, P. | Soussana, Jean-François, J.-F. | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Agro-Systèmes Territoires Ressources Mirecourt (ASTER Mirecourt) ; Institut National de la Recherche Agronomique (INRA) | Unité de recherche sur l'Ecosystème Prairial (UREP) ; Institut National de la Recherche Agronomique (INRA) | Agronomie et Fertilité Organique des Sols ; VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)
no sp Assessment of Nitrogen Fluxes to Air and Water from Site Scale to Continental Scale | Modelling complex systems such as farms often requires quantification of a large number of input factors. Sensitivity analyses are useful to reduce the number of input factors that are required to be measured or estimated accurately. Three methods of sensitivity analyses (The Morris method, the rank regression and correlation method and the Extended Fourrier Amplitude Sensitivity Test method) were compared in the case of the CERES-EGC model applied to crops of a dairy farm. The qualitative Morris method provided a screening of the input factors. The two other quantitative methods were used to investigate more thoroughly the effects of input factors. The two other quantitative methods were used to investigate more thoroughly the effectos on input factors on output variables.Despite differences in terms of concepts and assumptions, the three methods provided similar results. Among the 44 factors under study, N2O emissions were mainly sensitive to the fraction of N2O emitted during denitrification, the maximum rate of nitrification, the soil bulk density and the cropland area.
Mostrar más [+] Menos [-]Sensitivity analysis for models of greenhouse gas emissions at farm level. Case study of N2O emissions simulated by the CERES-EGC model Texto completo
2011
Drouet, Jean-Louis | Capian, Nicolas, | Fiorelli, Jean-Louis, | Blanfort, Vincent, | Capitaine, Mathieu | Duretz, Sylvia, | Gabrielle, Benoit, | Martin, Raphaël | Lardy, Romain | Cellier, Pierre, | Soussana, Jean-François,
Modelling complex systems such as farms often requires quantification of a large number of input factors. Sensitivity analyses are useful to reduce the number of input factors that are required to be measured or estimated accurately. Three methods of sensitivity analyses (The Morris method, the rank regression and correlation method and the Extended Fourrier Amplitude Sensitivity Test method) were compared in the case of the CERES-EGC model applied to crops of a dairy farm. The qualitative Morris method provided a screening of the input factors. The two other quantitative methods were used to investigate more thoroughly the effects of input factors. The two other quantitative methods were used to investigate more thoroughly the effectos on input factors on output variables.Despite differences in terms of concepts and assumptions, the three methods provided similar results. Among the 44 factors under study, N2O emissions were mainly sensitive to the fraction of N2O emitted during denitrification, the maximum rate of nitrification, the soil bulk density and the cropland area.
Mostrar más [+] Menos [-]Biosorption of divalent Pb, Cd and Zn on aragonite and calcite mollusk shells Texto completo
2011
Du, Yang | Lian, Fei | Zhu, Lingyan
The potential of using mollusk shell powder in aragonite (razor clam shells, RCS) and calcite phase (oyster shells, OS) to remove Pb²⁺, Cd²⁺ and Zn²⁺ from contaminated water was investigated. Both biogenic sorbents displayed very high sorption capacities for the three metals except for Cd on OS. XRD, SEM and XPS results demonstrated that surface precipitation leading to crystal growth took place during sorption. Calcite OS displayed a remarkably higher sorption capacity to Pb than aragonite RCS, while the opposite was observed for Cd. However, both sorbents displayed similar sorption capacities to Zn. These could be due to the different extent of matching in crystal lattice between the metal bearing precipitate and the substrates. The initial pH of the solution, sorbent’s dosage and grain size affected the removal efficiency of the heavy meals significantly, while the organic matter in mollusk shells affected the removal efficiency to a lesser extent.
Mostrar más [+] Menos [-]Combined effects of soil moisture and carbaryl to earthworms and plants: Simulation of flood and drought scenarios Texto completo
2011
Lima, Maria P.R. | Soares, Amadeu M.V.M. | Loureiro, Susana
Combined effects of soil moisture and carbaryl to earthworms and plants: Simulation of flood and drought scenarios Texto completo
2011
Lima, Maria P.R. | Soares, Amadeu M.V.M. | Loureiro, Susana
Studying tolerance limits in organisms exposed to climatic variations is key to understanding effects on behaviour and physiology. The presence of pollutants may influence these tolerance limits, by altering the toxicity or bioavailability of the chemical. In this work, the plant species Brassica rapa and Triticum aestivum and the earthworm Eisenia andrei were exposed to different levels of soil moisture and carbaryl, as natural and chemical stressors, respectively. Both stress factors were tested individually, as well as in combination. Acute and chronic tests were performed and results were discussed in order to evaluate the responses of organisms to the combination of stressors. When possible, data was fitted to widely employed models for describing chemical mixture responses. Synergistic interactions were observed in earthworms exposed to carbaryl and drought conditions, while antagonistic interactions were more representative for plants, especially in relation to biomass loss under flood-simulation conditions.
Mostrar más [+] Menos [-]Combined effects of soil moisture and carbaryl to earthworms and plants: simulation of flood and drought scenarios Texto completo
1000 | 2011
Lima, Maria P. R. | Soares, Amadeu M. V. M. | Loureiro, Susana
Studying tolerance limits in organisms exposed to climatic variations is key to understanding effects on behaviour and physiology. The presence of pollutants may influence these tolerance limits, by altering the toxicity or bioavailability of the chemical. In this work, the plant species Brassica rapa and Triticum aestivum and the earthworm Eisenia andrei were exposed to different levels of soil moisture and carbaryl, as natural and chemical stressors, respectively. Both stress factors were tested individually, as well as in combination. Acute and chronic tests were performed and results were discussed in order to evaluate the responses of organisms to the combination of stressors. When possible, data was fitted to widely employed models for describing chemical mixture responses. Synergistic interactions were observed in earthworms exposed to carbaryl and drought conditions, while antagonistic interactions were more representative for plants, especially in relation to biomass loss under flood-simulation conditions. (C) 2011 Elsevier Ltd. All rights reserved.
Mostrar más [+] Menos [-]Polychlorinated biphenyls in freshwater salmonids from the Kerguelen Islands in the Southern Ocean Texto completo
2011
Jaffal, A. | Givaudan, N. | Betoulle, S. | Terreau, A. | Paris-Palacios, S. | Biagianti-Risbourg, S. | Beall, E. | Roche, H.
Polychlorinated biphenyls in freshwater salmonids from the Kerguelen Islands in the Southern Ocean Texto completo
2011
Jaffal, A. | Givaudan, N. | Betoulle, S. | Terreau, A. | Paris-Palacios, S. | Biagianti-Risbourg, S. | Beall, E. | Roche, H.
The Subantarctic Kerguelen Islands (49°S, 70°E) contain freshwater ecosystems among the most isolated in the world. Concentrations of polychlorinated biphenyls (PCBs) were assessed in the muscle of 48 brook trout and 38 brown trout caught during summer and spring 2006 in the rivers, lakes and ponds of Kerguelen. The sum of 29 PCBs averaged 404 and 358ngg⁻¹ lipid, and dioxin-like PCB was 19 and 69ngg⁻¹ lipid, in brook and brown trout, respectively. The values showed a high variability and some fish accumulated PCBs at levels similar to those of fish from impacted areas. While inter-sex differences were limited, the season and the morphotype appeared to have the most influence. Fish captured in summer had muscle PCB concentrations about three times higher than those caught in spring and the ‘river’ morphotype of brook trout showed the highest PCB levels.
Mostrar más [+] Menos [-]Polychlorinated biphenyls in freshwater salmonids from the Kerguelen Islands in the Southern Ocean Texto completo
2011
Jaffal, Ali | Givaudan, Nicolas | Betoulle, Stéphane | Terreau, Alexandre | Paris-Palacios, Séverine | Biagianti-Risbourg, S. | Beall, Edward | Roche, H. | UNITE DE RECHERCHE VIGNES ET VINS DE CHAMPAGNE - STRESS ET ENVIRONNEMENT - EA2069 (URVV - SE) ; Université de Reims Champagne-Ardenne (URCA) | Ecologie Systématique et Evolution (ESE) ; Université Paris-Sud - Paris 11 (UP11)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS) | Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO) ; Université de Rennes (UR)-Institut Ecologie et Environnement (INEE) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR) ; Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS) | L'Institut polaire français Paul-Emile Victor (IPEV) ; Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.) | Ecologie Comportementale et Biologie des Populations de Poissons (ECOBIOP) ; Institut National de la Recherche Agronomique (INRA)-Université de Pau et des Pays de l'Adour (UPPA) | Programme IPEV 409 IMMUNOTOXKER
International audience | The Subantarctic Kerguelen Islands (49°S, 70°E) contain freshwater ecosystems among the most isolated in the world. Concentrations of polychlorinated biphenyls (PCBs) were assessed in the muscle of 48 brook trout and 38 brown trout caught during summer and spring 2006 in the rivers, lakes and ponds of Kerguelen. The sum of 29 PCBs averaged 404 and 358 ng g-1 lipid, and dioxin-like PCB was 19 and 69 ng g-1 lipid, in brook and brown trout, respectively. The values showed a high variability and some fish accumulated PCBs at levels similar to those of fish from impacted areas. While inter-sex differences were limited, the season and the morphotype appeared to have the most influence. Fish captured in summer had muscle PCB concentrations about three times higher than those caught in spring and the 'river' morphotype of brook trout showed the highest PCB levels.
Mostrar más [+] Menos [-]Polychlorinated biphenyls in freshwater salmonids from the Kerguelen Islands in the Southern Ocean Texto completo
2011
Jaffal, Ali | Givaudan, Nicolas | Betoulle, Stéphane | Terreau, Alexandre | Paris-Palacios, Séverine | Biagianti-Risbourg, S. | Beall, Edward | Roche, H. | UNITE DE RECHERCHE VIGNES ET VINS DE CHAMPAGNE - STRESS ET ENVIRONNEMENT - EA2069 (URVV - SE) ; Université de Reims Champagne-Ardenne (URCA) | Ecologie Systématique et Evolution (ESE) ; Université Paris-Sud - Paris 11 (UP11)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS) | Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO) ; Université de Rennes (UR)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) | L'Institut polaire français Paul-Emile Victor (IPEV) ; Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.) | Ecologie Comportementale et Biologie des Populations de Poissons (ECOBIOP) ; Institut National de la Recherche Agronomique (INRA)-Université de Pau et des Pays de l'Adour (UPPA) | Programme IPEV 409 IMMUNOTOXKER
International audience | The Subantarctic Kerguelen Islands (49°S, 70°E) contain freshwater ecosystems among the most isolated in the world. Concentrations of polychlorinated biphenyls (PCBs) were assessed in the muscle of 48 brook trout and 38 brown trout caught during summer and spring 2006 in the rivers, lakes and ponds of Kerguelen. The sum of 29 PCBs averaged 404 and 358 ng g-1 lipid, and dioxin-like PCB was 19 and 69 ng g-1 lipid, in brook and brown trout, respectively. The values showed a high variability and some fish accumulated PCBs at levels similar to those of fish from impacted areas. While inter-sex differences were limited, the season and the morphotype appeared to have the most influence. Fish captured in summer had muscle PCB concentrations about three times higher than those caught in spring and the 'river' morphotype of brook trout showed the highest PCB levels.
Mostrar más [+] Menos [-]Amending greenroof soil with biochar to affect runoff water quantity and quality Texto completo
2011
Beck, Deborah A. | Johnson, Gwynn R. | Spolek, Graig A.
Numbers of greenroofs in urban areas continue to grow internationally; so designing greenroof soil to reduce the amount of nutrients in the stormwater runoff from these roofs is becoming essential. This study evaluated changes in extensive greenroof water discharge quality and quantity after adding biochar, a soil amendment promoted for its ability to retain nutrients in soils and increase soil fertility. Prototype greenroof trays with and without biochar were planted with sedum or ryegrass, with barren soil trays used as controls. The greenroof trays were subjected to two sequential 7.4cm/h rainfall events using a rain simulator. Runoff from the rain events was collected and evaluated. Trays containing 7% biochar showed increased water retention and significant decreases in discharge of total nitrogen, total phosphorus, nitrate, phosphate, and organic carbon. The addition of biochar to greenroof soil improves both runoff water quality and retention.
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