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Cytochrome P450 1A1 expression in cetacean skin biopsies from the Indian Ocean
2011
Jauniaux, Thierry | Farnir, Frédéric | Fontaine, Michael | Kiszka, Jeremy | Sarlet, Michaël | Coignoul, Freddy
peer reviewed
Afficher plus [+] Moins [-]Lanscape control on diffuse pollution : a critical review on some investigations on phosphorus – retaining landscape features
2011
Dorioz , Jean Marcel (INRA , Thonon-Les-Bains (France). UMR 0042 Centre Alpin de Recherche sur les Réseaux Trophiques des Ecosystèmes limniques) | Gascuel-Odoux , Chantal (INRA , Rennes (France). UMR 1069 Sol Agro et hydrosystème Spatialisation) | Merot , Philippe (INRA , Rennes (France). UMR 1069 Sol Agro et hydrosystème Spatialisation) | Trevisan , Dominique (INRA , Thonon-Les-Bains (France). UMR 0042 Centre Alpin de Recherche sur les Réseaux Trophiques des Ecosystèmes limniques)
This text focuses on the identification, efficiencies, classification and management of landscape features having a potential buffer function regarding diffuse phosphorus, because of their specific structure (vegetation-soil) and of their location at the interface between sources (farm infrastructures, emitting fields…) and surface water bodies. These buffers are very diverse and correspond to natural landscape features (wetlands, riparian areas…) as well as manmade structures (constructed buffer strips or intermediate cases such as field margins, hedgerows). Their role and efficiency depends on the local factors controlling the retention processes (internal organisation and properties of the buffer), on the position within the watershed, and on the landscape context which reciprocally determines the overall buffer capacity of a watershed. On that basis, we recognize the diversity of the buffers in structure and functioning and thus in the way they attenuate the signal, their limitations (sustainability, side effects) and their hierarchic organisation at the watershed scale.
Afficher plus [+] Moins [-]Use of the MicroResp™ method to assess pollution-induced community tolerance to metals for lotic biofilms
2011
Tlili , Ahmed (Institut National de Recherche en Sciences et Technologies pour l'Environnement et l'Agriculture, Lyon cedex 09(France). UR MAEP) | Maréchal , Marjorie (Institut National de Recherche en Sciences et Technologies pour l'Environnement et l'Agriculture, Lyon cedex 09(France). UR MAEP) | Montuelle , Bernard (Institut National de Recherche en Sciences et Technologies pour l'Environnement et l'Agriculture, Lyon cedex 09(France). UR MAEP) | Volat , Bernadette (Institut National de Recherche en Sciences et Technologies pour l'Environnement et l'Agriculture, Lyon cedex 09(France). UR MAEP) | Dorigo , Ursula (INRA , Thonon-Les-Bains (France). UMR 0042 Centre Alpin de Recherche sur les Réseaux Trophiques des Ecosystèmes limniques) | Berard , Annette (INRA , Avignon (France). UMR 1114 Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes )
Understanding the ecological status of aquatic ecosystems and the impact of anthropogenic contamination requires correlating exposure to toxicants with impact on biological communities. Several tools exist for assessing the ecotoxicity of substances, but there is still a need for new tools that are ecologically relevant and easy to use. We have developed a protocol based on the substrate-induced respiration of a river biofilm community, using the MicroResp™ technique, in a pollution-induced community tolerance approach. The results show that MicroResp™ can be used in bioassays to assess the toxicity toward biofilm communities of a wide range of metals (Cu, Zn, Cd, Ag, Ni, Fe, Co, Al and As). Moreover, a community-level physiological profile based on the mineralization of different carbon substrates was established. Finally, the utility of MicroResp™ was confirmed in an in-situ study showing gradient of tolerance to copper correlated to a contamination gradient of this metal in a small river. A modified MicroResp™ technique as a tool for measuring induced tolerance to heavy metals of a microbial biofilm community
Afficher plus [+] Moins [-]Atmospheric phenanthrene pollution modulates carbon allocation in red clover (Trifolium pratense L.)
2011
Desalme, Dorine | Binet, Philippe | Epron, Daniel, D. | Bernard, Nadine | Gilbert, Daniel | Toussaint, Marie-Laure | Plain, Caroline | Chiapusio, Geneviève | Laboratoire Chrono-environnement (UMR 6249) (LCE) ; Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC) ; Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC) | Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Pays de Montbeliard Agglomeration (PMA)
International audience | The influence of atmospheric phenanthrene (PHE) exposure (160 mgm 3) during one month on carbon allocation in clover was investigated by integrative (plant growth analysis) and instantaneous 13CO2 pulse-labelling approaches. PHE exposure diminished plant growth parameters (relative growth rate and net assimilation rate) and disturbed photosynthesis (carbon assimilation rate and chlorophyll content), leading to a 25% decrease in clover biomass. The root-shoot ratio was significantly enhanced (from 0.32 to 0.44). Photosynthates were identically allocated to leaves while less allocated to stems and roots. PHE exposure had a significant overall effect on the 13C partitioning among clover organs as more carbon was retained in leaves at the expense of roots and stems. The findings indicate that PHE decreases root exudation or transfer to symbionts and in leaves, retains carbon in a non-structural form diverting photosynthates away from growth and respiration (emergence of an additional C loss process).
Afficher plus [+] Moins [-]DNA damage in caged Gammarus fossarum amphipods: A tool for freshwater genotoxicity assessment | Dommages à l'ADN chez l'amphipode Gammarus fossarum encagés : un outil pour le suivi de la génotoxicité des milieux dulçaquicoles
2011
Lacaze, Emilie | Devaux, Alain | Mons, R. | Bony, Sylvie | Garric, Jeanne | Geffard, Adeline | Geffard, Olivier | Milieux aquatiques, écologie et pollutions (UR MALY) ; Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF) | Institut National de la Recherche Agronomique (INRA) | Université de Reims Champagne-Ardenne (URCA)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA | International audience | The aim of this study was to propose a tool for freshwater environmental genotoxicity assessment using Gammarus fossarum, a high ecologically relevant species. In a first part, gammarids were caged upstream and downstream wastewater treatment plant effluent output. The sensitivity of genotoxic responses of haemocytes, oocytes and spermatozoa was compared using the Comet assay. Spermatozoa appeared to be the most sensitive, suitable and relevant cell type for genotoxicity risk assessment. In a second part, a watershed-scale study was conducted over 2 years to evaluate the applicability of our caging procedure. The genotoxic impact of a contamination was followed, taking into account seasonal variability. DNA damage in spermatozoa exhibited low basal level and low variability in control upstream sites, providing a reliable discrimination of polluted sites. Finally, DNA damage in caged G. fossarum has been proved to be a sensitive and reproducible tool for freshwater genotoxicity assessment.
Afficher plus [+] Moins [-]Toothed whales in the northwestern Mediterranean: Insight into their feeding ecology using chemical tracers
2011
Praca, Emilie | Laran, Sophie | Lepoint, Gilles | Thomé, Jean-Pierre | Quetglas, Antoni | Belcari, Paola | Sartor, Paolo | Dhermain, Frank | Ody, Denis | Tapie, Nathalie | Budzinski, Hélène | Das, Krishna
peer reviewed | Risso’s dolphins, pilot whales and sperm whales rarely strand in the northwestern Mediterranean. Thus, their feeding ecology, through the analysis of stomach contents, is poorly known. The aim of this study was to gain further insight into the segregation/superposition of the diet and habitat of Risso’s dolphins, pilot whales and sperm whales using chemical tracers, namely, stable isotopes (d13C, d15N) and orga- nochlorines. Significantly different d15N values were obtained in Risso’s dolphins (11.7 ± 0.7‰), sperm whales (10.8 ± 0.3‰) and pilot whales (9.8 ± 0.3‰), revealing different trophic levels. These differences are presumably due to various proportions of Histioteuthidae cephalopods in each toothed whale’s diet. Similar d13C contents between species indicated long-term habitat superposition or corroborated impor- tant seasonal migrations. Lower congener 180 concentrations (8.20 vs. 21.73 lg.g1 lw) and higher tDDT/ tPCB ratios (0.93 vs. 0.42) were observed in sperm whales compared with Risso’s dolphins and may indi- cate wider migrations for the former. Therefore, competition between these species seems to depend on different trophic levels and migration patterns.
Afficher plus [+] Moins [-]Bioavailability of particulate metal to zebra mussels: Biodynamic modelling shows that assimilation efficiencies are site-specific
2011
Bourgeault, A. | Gourlay-Francé, C. | Priadi Rianti, C. | Ayrault, Sophie | Tusseau-Vuillemin, Marie-Hélène | Hydrosystèmes et Bioprocédés (UR HBAN) ; Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF) | Fédération Île-de-France de Recherche sur l'Environnement (FIRE) ; Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-AgroParisTech-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) | Géochimie Des Impacts (GEDI) ; Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) | Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA | International audience | This study investigates the ability of the biodynamic model to predict the trophic bioaccumulation of cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni) and zinc (Zn) in a freshwater bivalve. Zebra mussels were transplanted to three sites along the Seine River (France) and collected monthly for 11 months. Measurements of the metal body burdens in mussels were compared with the predictions from the biodynamic model. The exchangeable fraction of metal particles did not account for the bioavailability of particulate metals, since it did not capture the differences between sites. The assimilation efficiency (AE) parameter is necessary to take into account biotic factors influencing particulate metal bioavailability. The biodynamic model, applied with AEs from the literature, overestimated the measured concentrations in zebra mussels, the extent of overestimation being site-specific. Therefore, an original methodology was proposed for in situ AE measurements for each site and metal.
Afficher plus [+] Moins [-]Molecular effects and bioaccumulation of levonorgestrel in the non-target organism Dreissena polymorpha
2011
Contardo-Jara, Valeska | Lorenz, Claudia | Pflugmacher, Stephan | Nutzmann, Gunnar | Kloas, Werner | Wiegand, Claudia | Ecophysiology and Aquaculture, Leibniz Berlin ; Leibniz | Ecohydrology, Leibniz Berlin ; Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) | 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)-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) | University of Southern Denmark (SDU)
International audience | Bioaccumulation and effects of the contraceptive hormone levonorgestrel were examined in the nontarget organism Dreissena polymorpha. Molecular biomarkers of biotransformation, elimination, antioxidant defence and protein damage were analyzed after exposure to increasing concentrations of levonorgestrel in a flow-through system. The lowest concentration (0.312 mg L-1) was 100-fold bioconcentrated within four days. A decrease of the bioconcentration factor was observed within one week for the highest test concentrations (3.12 and 6.24 mg L-1) suggesting enhanced excretory processes. The immediate mRNA up-regulation of pi class glutathione S-transferase proved that phase II biotransformation processes were induced. Disturbance of fundamental cell functions was assumed since the aryl hydrocarbon receptor has been permanently down-regulated. mRNA up-regulation of P-glycoprotein, superoxide dismutase and metallothioneine suggested enhanced elimination processes and ongoing oxidative stress. mRNA up-regulation of heat shock protein 70 in mussels exposed to the two highest concentrations clearly indicated impacts on protein damage.
Afficher plus [+] Moins [-]NitroScape: A model to integrate nitrogen transfers and transformations in rural landscapes
2011
Duretz, Sylvia, S. | Drouet, Jean-Louis | Durand, Patrick | Hutchings, N.J., N.J. | Theobald, M.R., M.R. | Salmon-Monviola, Jordy | Dragosits, U., U. | Maury, Olivier, O. | Sutton, M.A., M.A. | Cellier, Pierre, P. | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Sol Agro et hydrosystème Spatialisation (SAS) ; Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST | Department of Agroecology ; Aarhus University [Aarhus] | Department of Chemistry and Agricultural Analysis ; Universidad Politécnica de Madrid (UPM)
no sp Assessment of Nitrogen Fluxes to Air and Water from Site Scale to Continental Scale | Modelling nitrogen transfer and transformation at the landscape scale is relevant to estimate the mobility of the reactive forms of nitrogen (Nr) and the associated threats to the environment. Here we describe the development of a spatially and temporally explicit model to integrate Nr transfer and transformation at the landscape scale. The model couples four existing models, to simulate atmospheric, farm, agro-ecosystem and hydrological Nr fluxes and transformations within a landscape. Simulations were carried out on a theoretical landscape consisting of pig-crop farms interspersed with unmanaged ecosystems. Simulation results illustrated the effect of spatial interactions between landscape elements on Nr fluxes and losses to the environment. More than 10% of the total N2O emissions were due to indirect emissions. The nitrogen budgets and transformations of the unmanaged ecosystems varied considerably, depending on their location within the landscape. The model represents a new tool for assessing the effect of changes in landscape structure on Nr fluxes.
Afficher plus [+] Moins [-]Assessment of aided phytostabilization of copper-contaminated soil by X-ray absorption spectroscopy and chemical extractions
2011
Kumpiene, Jurate | Mench, Michel | Bes, Clémence | Fitts, Jeffrey P. | Luleå University of Technology = Luleå Tekniska Universitet (LUT) | Biodiversité, Gènes & Communautés (BioGeCo) ; Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB) | Brookhaven National Laboratory [Upton, NY] (BNL) ; UT-Battelle, LLC-Stony Brook University [SUNY] (SBU) ; State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE)
International audience | Field plots were established at a timber treatment site to evaluate remediation of Cu contaminated topsoils with aided phytostabilization. Soil containing 2600 mg kg−1 Cu was amended with a combination of 5 wt% compost and 2 wt% iron grit, and vegetated. Sequential extraction was combined with extended X-ray absorption fine structure (EXAFS) spectroscopy to correlate changes in Cu distribution across five fractions with changes in the predominant Cu compounds two years after treatment in parallel treated and untreated field plots. Exchangeable Cu dominated untreated soil, most likely as Cu(II) species non-specifically bound to natural organic matter. The EXAFS spectroscopic results are consistent with the sequential extraction results, which show a major shift in Cu distribution as a result of soil treatment to the fraction bound to poorly crystalline Fe oxyhydroxides forming binuclear inner-sphere complexes.
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