Refine search
Results 411-420 of 1,956
Assessing ecotoxicity and uptake of metals and metalloids in relation to two different earthworm species (Eiseina hortensis and Lumbricus terrestris) Full text
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) Full text
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.
Show more [+] Less [-]Assessing ecotoxicity and uptake of metals and metalloids in relation to two different earthworm species (Eiseina hortensis and Lumbricus terrestris) Full text
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)-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)-Centre National d'Études Spatiales [Toulouse] (CNES)-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.
Show more [+] Less [-]Assessing ecotoxicity and uptake of metals and metalloids in relation to two different earthworm species (Eiseina horterzsis and Lumbricus terrestris) Full text
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.
Show more [+] Less [-]Assessing ecotoxicity and uptake of metals and metalloids in relation to two different earthworm species (Eiseina horterzsis and Lumbricus terrestris) Full text
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.
Show more [+] Less [-]Influence of age, sex and breeding status on mercury accumulation patterns in the wandering albatross Diomedea exulans Full text
2013
Tavares, S. | Xavier, J.C. | Phillips, R.A. | Pereira, M.E. | Pardal, M.A.
Influence of age, sex and breeding status on mercury accumulation patterns in the wandering albatross Diomedea exulans Full text
2013
Tavares, S. | Xavier, J.C. | Phillips, R.A. | Pereira, M.E. | Pardal, M.A.
Although mercury bio-amplifies through the food chain and accumulates in top predators, mercury concentrations in tissues of the wandering albatross are greater than in any other vertebrate, including closely related species. In order to explore the alternative explanations for this pattern, we measured total mercury concentrations in feathers, plasma and blood cells of wandering albatrosses of known age, sex and breeding status sampled at South Georgia. Mercury concentrations were low in feathers and blood components of chicks, and higher in the feathers of young pre-breeders than in feathers or blood of older pre-breeders and breeding adults. There was no effect of sex on mercury concentrations in the feathers of pre-breeders or breeding adults, whereas levels were significantly higher in blood cells of breeding females than males. The high feather mercury concentrations of young pre-breeders compared with older birds suggest an increase in moult frequency as birds approach maturity.
Show more [+] Less [-]Influence of age, sex and breeding status on mercury accumulation patterns in the wandering albatross Diomedea exulans Full text
2013
Tavares, S. | Xavier, J. C. | Phillips, R. A. | Pereira, M. E. | Pardal, M. A.
Although mercury bio-amplifies through the food chain and accumulates in top predators, mercury concentrations in tissues of the wandering albatross are greater than in any other vertebrate, including closely related species. In order to explore the alternative explanations for this pattern, we measured total mercury concentrations in feathers, plasma and blood cells of wandering albatrosses of known age, sex and breeding status sampled at South Georgia. Mercury concentrations were low in feathers and blood components of chicks, and higher in the feathers of young pre-breeders than in feathers or blood of older pre-breeders and breeding adults. There was no effect of sex on mercury concentrations in the feathers of pre-breeders or breeding adults, whereas levels were significantly higher in blood cells of breeding females than males. The high feather mercury concentrations of young pre-breeders compared with older birds suggest an increase in moult frequency as birds approach maturity. | This work was supported by the Portuguese Foundation for the Science and Technology (FCT) through a PhD grant to Sílvia Tavares (SFRH/BD/48908/2008),co-funded by the European Social Fund and Portuguese Government National Funds, and through the project POLAR. This paper represents a contribution to the British Antarctic Survey Ecosystems Programme, the national program PROPOLAR and the international programs of ICED and SCAR AnT-ERA. | published
Show more [+] Less [-]Determination and occurrence of secondary alkane sulfonates (SAS) in aquatic environments Full text
2013
Baena-Nogueras, Rosa María | González-Mazo, Eduardo | Lara-Martín, Pablo A.
Determination and occurrence of secondary alkane sulfonates (SAS) in aquatic environments Full text
2013
Baena-Nogueras, Rosa María | González-Mazo, Eduardo | Lara-Martín, Pablo A.
A new methodology has been developed for the determination of secondary alkane sulfonates (SAS), an anionic surfactant, in environmental matrices. Sediment and sludge samples were extracted using pressurized liquid extraction and sonication, whereas wastewater and surface water samples were processed using solid-phase extraction. Extraction recoveries were acceptable for both aqueous (78–120%) and solid samples (83–100%). Determination of SAS was carried out by high or ultra performance liquid chromatography – mass spectrometry using ion trap and time-of-flight detectors. The methodology was applied to samples from Guadalete River (SW Spain), where SAS concentrations below 1 μg L−1 were measured in surface water, and from 72 to 9737 μg kg−1 in sediments. Differential partitioning was observed for SAS homologues as those having a longer hydrocarbon chain which preferentially sorbed onto particulate matter. A preliminary environmental risk assessment also showed that SAS measured levels were not harmful to the aquatic community in the sampling area.
Show more [+] Less [-]Determination and occurrence of secondary alkane sulfonates (SAS) in aquatic environments Full text
Baena Nogueras, Rosa María | González Mazo, Eduardo | Lara Martín, Pablo Antonio | Química Física
A new methodology has been developed for the determination of secondary alkane sulfonates (SAS), an anionic surfactant, in environmental matrices. Sediment and sludge samples were extracted using pressurized liquid extraction and sonication, whereas wastewater and surface water samples were processed using solid-phase extraction. Extraction recoveries were acceptable for both aqueous (78-120%) and solid samples (83-100%). Determination of SAS was carried out by high or ultra performance liquid chromatography e mass spectrometry using ion trap and time-of-flight detectors. The methodology was applied to samples from Guadalete River (SW Spain), where SAS concentrations below 1 mg L 1 were measured in surface water, and from 72 to 9737 mg kg 1 in sediments. Differential partitioning was observed for SAS homologues as those having a longer hydrocarbon chain which preferentially sorbed onto particulate matter. A preliminary environmental risk assessment also showed that SAS measured levels were not harmful to the aquatic community in the sampling area.
Show more [+] Less [-]Holm Oak (Quercus ilex L.) canopy as interceptor of airborne trace elements and their accumulation in the litter and topsoil Full text
2013
Fantozzi, Federica | Monaci, Fabrizio | Blanusa, Tijana | Bargagli, Roberto
Holm Oak (Quercus ilex L.) canopy as interceptor of airborne trace elements and their accumulation in the litter and topsoil Full text
2013
Fantozzi, Federica | Monaci, Fabrizio | Blanusa, Tijana | Bargagli, Roberto
We investigated the role of urban Holm Oak (Quercus ilex L.) trees as an airborne metal accumulators and metals' environmental fate. Analyses confirmed Pb, Cd, Cu and Zn as a main contaminants in Siena's urban environment; only Pb concentrations decreased significantly compared to earlier surveys. Additionally, we determined chemical composition of tree leaves, litter and topsoil (underneath/outside tree crown) in urban and extra-urban oak stands. Most notably, litter in urban samples collected outside the canopy had significantly lower concentrations of organic matter and higher concentrations of Pb, Cu, Cd and Zn than litter collected underneath the canopy. There was a greater metals' accumulation in topsoil, in samples collected under the tree canopy and especially near the trunk (‘stemflow area’). Thus, in urban ecosystems the Holm Oak stands likely increase the soil capability to bind metals.
Show more [+] Less [-]Holm Oak (Quercus ilex L.) canopy as interceptor of airborne trace elements and their accumulation in the litter and topsoil Full text
2013
Fantozzi, Federica | Monaci, Fabrizio | Blanusa, Tijana | Bargagli, Roberto
We investigated the role of urban Holm Oak (Quercus ilex L.) trees as airborne metal accumulators and metals' environmental fate. Analyses confirmed Pb, Cd, Cu and Zn as main contaminants in Siena's urban environment; only Pb concentrations decreased significantly compared to earlier surveys. Additionally, we determined chemical composition of tree leaves, litter and topsoil (underneath/outside tree crown) in urban and extra-urban oak stands. Most notably, litter in urban samples collected outside the canopy had significantly lower concentrations of organic matter and higher concentrations of Pb, Cu, Cd and Zn than litter collected underneath the canopy. There was a greater metals' accumulation in topsoil, in samples collected under the tree canopy and especially near the trunk ('stemflow area'). Thus, in urban ecosystems the Holm Oak stands likely increase the soil capability to bind metals.
Show more [+] Less [-]Salinisation of rivers: An urgent ecological issue Full text
2013
Cañedo-Argüelles, Miguel | Kefford, Ben J. | Piscart, Christophe | Prat i Fornells, Narcís | Schäfer, Ralf B. | Schulz, Claus-Jürgen
Salinisation of rivers: An urgent ecological issue Full text
2013
Cañedo-Argüelles, Miguel | Kefford, Ben J. | Piscart, Christophe | Prat i Fornells, Narcís | Schäfer, Ralf B. | Schulz, Claus-Jürgen
Secondary salinisation of rivers and streams is a global and growing threat that might be amplified by climate change. It can have many different causes, like irrigation, mining activity or the use of salts as de-icing agents for roads. Freshwater organisms only tolerate certain ranges of water salinity. Therefore secondary salinisation has an impact at the individual, population, community and ecosystem levels, which ultimately leads to a reduction in aquatic biodiversity and compromises the goods and services that rivers and streams provide. Management of secondary salinization should be directed towards integrated catchment strategies (e.g. benefiting from the dilution capacity of the rivers) and identifying threshold salt concentrations to preserve the ecosystem integrity. Future research on the interaction of salinity with other stressors and the impact of salinization on trophic interactions and ecosystem properties is needed and the implications of this issue for human society need to be seriously considered.
Show more [+] Less [-]Salinisation of rivers: An urgent ecological issue Full text
2012
Canedo-Argueelles, M | Kefford, BJ | Piscart, C | Prat, N | Schaefer, RB | Schulz, C-J
Effects of ozone on stomatal responses to environmental parameters (blue light, red light, CO2 and vapour pressure deficit) in three Populus deltoides × Populus nigra genotypes Full text
2013
Dumont, Jenny | Spicher, Fabien | Montpied, Pierre | Dizengremel, Pierre | Jolivet, Yves | Le Thiec, Didier
Effects of ozone on stomatal responses to environmental parameters (blue light, red light, CO2 and vapour pressure deficit) in three Populus deltoides × Populus nigra genotypes Full text
2013
Dumont, Jenny | Spicher, Fabien | Montpied, Pierre | Dizengremel, Pierre | Jolivet, Yves | Le Thiec, Didier
The effect of ozone (O3) on stomatal regulation was studied in three Euramerican poplar genotypes (Populus deltoides × Populus nigra: Carpaccio, Cima and Robusta). The impact of O3 on stomatal conductance responses to variations in blue light, red light, CO2 concentration and vapour pressure deficit (VPD) was studied. Upon O3 exposure, a sluggish response of stomatal movements was observed, characterized by slower reactions to increases in blue light intensity, CO2 concentration and VPD, and lower amplitude of the response to variations in light intensity. That sluggish response should be taken into account in stomatal conductance models for phytotoxic ozone dose (PODY) calculations. The speed of the response to variations in environmental parameters appears as a determining factor of genotype-related sensitivity.
Show more [+] Less [-]Effects of ozone on stomatal responses to environmental parameters (blue light, red light, CO2 and vapour pressure deficit) in three Populus deltoides × Populus nigra genotypes Full text
2013
Dumont, Jennifer | Spicher, Fabien | Montpied, Pierre | Dizengremel, Pierre | Jolivet, Yves | Le Thiec, Didier
The effect of ozone (O3) on stomatal regulation was studied in three Euramerican poplar genotypes (Populus deltoides Populus nigra: Carpaccio, Cima and Robusta). The impact of O3 on stomatal conductance responses to variations in blue light, red light, CO2 concentration and vapour pressure deficit (VPD) was studied. Upon O3 exposure, a sluggish response of stomatal movements was observed, characterized by slower reactions to increases in blue light intensity, CO2 concentration and VPD, and lower amplitude of the response to variations in light intensity. That sluggish response should be taken into account in stomatal conductance models for phytotoxic ozone dose (PODY) calculations. The speed of the response to variations in environmental parameters appears as a determining factor of genotyperelated sensitivity.
Show more [+] Less [-]Influence of socio-demographic and diet determinants on the levels of mercury in preschool children from a Mediterranean island Full text
2013
Garí, Mercè | Grimalt, Joan O. | Torrent, Maties | Sunyer, Jordi
Influence of socio-demographic and diet determinants on the levels of mercury in preschool children from a Mediterranean island Full text
2013
Garí, Mercè | Grimalt, Joan O. | Torrent, Maties | Sunyer, Jordi
Mercury levels measured in 302 hair samples of 4 year-old children from Menorca (western Mediterranean Sea) are reported. Their concentrations, arithmetic mean 1.4 μg/g, ranging between 0.040 μg/g and 10 μg/g, were higher than in other children inland populations but lower than in previously studied island cohorts, e.g. Faroe, Madeira and Seychelles. 20% of the samples were above the WHO recommended values. Higher concentrations in females than males were observed. Frequent consumption of fish and other seafood were significantly related to the observed mercury concentrations. Oily fish was the main source of this pollutant but shellfish and squid consumption were also associated with high mercury concentrations. Maternal smoking, occupational status or previous siblings were also found to significantly influence the levels of this pollutant. McCarthy Scales of Children's Abilities used to assess children's motor and cognitive abilities did not show association with mercury concentrations at 4 years of age.
Show more [+] Less [-]Influence of socio-demographic and diet determinants on the levels of mercury in preschool children from a Mediterranean island Full text
2013
Garí, Mercè | Grimalt, Joan O. | Torrent, Maties | Sunyer, Jordi | European Research Council | Consejo Superior de Investigaciones Científicas [https://ror.org/02gfc7t72]
Mercury levels measured in 302 hair samples of 4 year-old children from Menorca (western Mediterranean Sea) are reported. Their concentrations, arithmetic mean 1.4 μg/g, ranging between 0.040 μg/g and 10 μg/g, were higher than in other children inland populations but lower than in previously studied island cohorts, e.g. Faroe, Madeira and Seychelles. 20% of the samples were above the WHO recommended values. Higher concentrations in females than males were observed. Frequent consumption of fish and other seafood were significantly related to the observed mercury concentrations. Oily fish was the main source of this pollutant but shellfish and squid consumption were also associated with high mercury concentrations. Maternal smoking, occupational status or previous siblings were also found to significantly influence the levels of this pollutant. McCarthy Scales of Children's Abilities used to assess children's motor and cognitive abilities did not show association with mercury concentrations at 4 years of age. | This study was funded by Fundació La Marató TV3 (090431), the Spanish Ministries of Science and Innovation and Health (Consolider Ingenio GRACCIE, CSD2007-00067, FIS-00/0021-02) and the EU funded project ArcRisk (FP7-ENV-2008-1-226534) and Generalitat de Catalunya (Research Group 2009SGR1178). M.G. thanks a grant from the JAE Predoctoral program (CSIC). | Peer reviewed
Show more [+] Less [-]Comparative effects of several cyclodextrins on the extraction of PAHs from an aged contaminated soil Full text
2013
Comparative effects of several cyclodextrins on the extraction of PAHs from an aged contaminated soil Full text
2013
The objective of the present study was to characterise the polycyclic aromatic hydrocarbons (PAHs) content of an aged contaminated soil and to propose remediation techniques using cyclodextrins (CDs). Four CDs solutions were tested as soil decontamination tool and proved more efficient in extracting PAHs than when an aqueous solution was used; especially two chemically modified CDs resulted in higher extraction percentages than natural β-CD. The highest extraction percentages were obtained for 3-ring PAHs, because of the appropriate size and shape of these compounds relative to those of the hydrophobic cavities of the CDs studied. A detailed mechanistic interpretation of the chemical modification of CDs on the extraction of the different PAHs has been performed, and connected with the role that the different hydrophobicities of the PAHs play in the extraction behaviour observed for the 16 PAHs, limiting their accessibility and the remaining risk of those PAHs not extractable by CDs.
Show more [+] Less [-]Comparative effects of several cyclodextrins on the extraction of PAHs from an aged contaminated soil Full text
2013
Sánchez Trujillo, Mª Antonia | Morillo González, Esmeralda | Villaverde Capellán, J. | Lacorte Bruguera, Silvia
7 páginas.-- 3 figuras.-- 2 tablas.-- 52 referencias.-- Supplementary data | The objective of the present study was to characterise the polycyclic aromatic hydrocarbons (PAHs) content of an aged contaminated soil and to propose remediation techniques using cyclodextrins (CDs). Four CDs solutions were tested as soil decontamination tool and proved more efficient in extracting PAHs than when an aqueous solution was used; especially two chemically modified CDs resulted in higher extraction percentages than natural β-CD. The highest extraction percentages were obtained for 3-ring PAHs, because of the appropriate size and shape of these compounds relative to those of the hydrophobic cavities of the CDs studied. A detailed mechanistic interpretation of the chemical modification of CDs on the extraction of the different PAHs has been performed, and connected with the role that the different hydrophobicities of the PAHs play in the extraction behaviour observed for the 16 PAHs, limiting their accessibility and the remaining risk of those PAHs not extractable by CDs. © 2013 Elsevier Ltd. All rights reserved. | The authors thank to Dr. J.R. Gallego from the Universidad de Oviedo for providing the contaminated soil sample. Support from projects CTM2006-04626 and CTM2009-07335, Spanish Ministry of Science and Innovation (co-funded by Fondo Europeo de Desarrollo Regional, FEDER), are greatly appreciated. M.A. Sánchez-Trujillo acknowledges a research contract from CSIC (JAEPre 0800763) cofinanced by Fondo Social Europeo (FSE). | Peer Reviewed
Show more [+] Less [-]Degradation of multiwall carbon nanotubes by bacteria Full text
2013
Zhang, Liwen | Petersen, Elijah J. | Habteselassie, Mussie Y. | Mao, Liang | Huang, Qingguo
Understanding the environmental transformation of multiwall carbon nanotubes (MWCNTs) is important to their life cycle assessment and potential environmental impacts. We report that a bacterial community is capable of degrading 14C-labeled MWCNTs into 14CO2 in the presence of an external carbon source via co-metabolism. Multiple intermediate products were detected, and genotypic characterization revealed three possible microbial degraders: Burkholderia kururiensis, Delftia acidovorans, and Stenotrophomonas maltophilia. This result suggests that microbe/MWCNTs interaction may impact the long-term fate of MWCNTs.
Show more [+] Less [-]Update on the cometabolism of organic pollutants by bacteria Full text
2013
Nzila, Alexis
Each year, tons of various types of molecules pollute our environment, and their elimination is one of the major challenges human kind is facing. Among the strategies to eliminate these pollutants is their biodegradation by microorganisms. However, many pollutants cannot be used efficiently as growth substrates by microorganisms. Biodegradation of such molecules by cometabolism has been reported, which is the ability of a microorganism to biodegrade a pollutant without using it as a growth-substrate (non-growth-substrate), while sustaining its own growth by assimilating a different substrate (growth-substrate). This approach has been used in the field of bioremediation, however, its potential has not been fully exploited yet. This review summarises the work carried out on the cometabolism of important recalcitrant pollutants, and presents strategies that can be used to improve ways of identifying microorganisms that can cometabolise such recalcitrant pollutants.
Show more [+] Less [-]