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Ecotoxicological impact of the antihypertensive valsartan on earthworms, extracellular enzymes and soil bacterial communities
2021
Gallego, Sara | Nos, David | Montemurro, Nicola | Sanchez-Hernandez, Juan | Pérez, Sandra | Solé, Montserrat | Martin-Laurent, Fabrice | Agroécologie [Dijon] ; Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Institute of Environmental Assessment and Water Research (IDAEA) ; Consejo Superior de Investigaciones Cientificas = Spanish National Research Council (CSIC) | Inst Marine Sci ICM CSIC, Renewable Marine Resources Dept, Barcelona, Spain. | Univ Castilla La Mancha, Inst Environm Sci ICAM, Lab Ecotoxicol, Toledo 45071, Spain
International audience | The use of reclaimed water in agriculture represents a promising alternative to relieve pressure on freshwater supplies, especially in arid or semiarid regions facing water scarcity. However, this implies introducing micropollutants such as pharmaceutical residues into the environment. The fate and the ecotoxicological impact of valsartan, an antihypertensive drug frequently detected in wastewater effluents, were evaluated in soil-earthworm microcosms. Valsartan dissipation in the soil was concomitant with valsartan acid formation. Although both valsartan and valsartan acid accumulated in earthworms, no effect was observed on biomarkers of exposure (acetylcholinesterase, glutathione S-transferase and carboxylesterase activities). The geometric mean index of soil enzyme activity increased in the soils containing earthworms, regardless of the presence of valsartan. Therefore, earthworms increased soil carboxylesterase, dehydrogenase, alkaline phosphatase, beta-glucosidase, urease and protease activities. Although bacterial richness significantly decreased following valsartan exposure, this trend was enhanced in the presence of earthworms with a significant impact on both alpha and beta microbial diversity. The operational taxonomic units involved in these changes were related to four (Proteobacteria, Bacteroidetes, Actinobacteria and Firmicutes) of the eight most abundant phyla. Their relative abundances significantly increased in the valsartan-treated soils containing earthworms, suggesting the presence of potential valsartan degraders. The ecotoxicological effect of valsartan on microbes was strongly altered in the earthworm-added soils, hence the importance of considering synergistic effects of different soil organisms in the environmental risk assessment of pharmaceutical active compounds. (C) 2021 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]LONG-TERM stability of arsenic in iron amended contaminated soil
2021
Kumpiene, Jurate | Carabante, Ivan | Kasiuliene, Alfreda | Austruy, Annabelle | Mench, Michel | Luleå University of Technology = Luleå Tekniska Universitet (LUT) | Institut Ecocitoyen pour la Connaissance des Pollutions [Fos-sur-Mer] | Biodiversité, Gènes & Communautés (BioGeCo) ; Université de Bordeaux (UB)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | The La Combe de Saut experiment was funded by ADEME and the LIFE project DIFPOLMINE. The Reppel experiment was set up under the EU FP5 Phytorehab project. Experiments in Sweden were financed by the Swedish Research Council FORMAS and European Union Structural Funds and New Objective 1, North Sweden Soil Remediation Center (MarksaneringsCentrum Norr - MCN). Stanford Synchrotron Radiation Lightsource is acknowledged for granting our beamtime proposal (4663) under which X-Ray absorption measurements presented in this work were performed.
International audience | This study aimed at elucidating the long-term efficiency of soil remediation where chemical stabilization of arsenic (As) contaminated soil using zerovalent iron (Fe) amendments was applied. A combination of chemical extraction and extended X-Ray absorption fine structure (EXAFS) spectroscopy technique was applied on soils collected from five laboratory and field experiments in Sweden and France. All soils were treated with 1 wt% of zerovalent Fe grit 2e15 years prior to the sampling. The results indicate that all studied soils, despite the elapsed time since their amendment with Fe grit, had substantial amounts of ferrihydrite and/or lepidocrocite. These metastable and the most reactive Fe (oxyhydr)oxides (mainly ferrihydrite) were still present in substantial amounts even in the soil that was treated 15 years prior to the sampling and contributed most to the As immobilisation in the amended soils. This increases confidence in the long-term efficiency of As immobilisation using zerovalent Fe amendments. Both applied methods, sequential extraction and EXAFS, were in line for most of the samples in terms of their ability to highlight As immobilisation by poorly crystalline Fe phases.
Afficher plus [+] Moins [-]Factors affecting farmers’ use of organic and inorganic fertilizers in South Asia
2021
Aryal, J.P. | Sapkota, T. | Krupnik, T.J. | Rahut, D.B. | Jat, M.L. | Stirling, C.
Fertilizer, though one of the most essential inputs for increasing agricultural production, is a leading cause of nitrous oxide emissions from agriculture, contributing significantly to global warming. Therefore, understanding factors affecting farmers’ use of fertilizers is crucial to develop strategies to improve its efficient use and to minimize its negative impacts. Using data from 2528 households across the Indo-Gangetic Plains in India, Nepal, and Bangladesh, this study examines the factors affecting farmers’ use of organic and inorganic fertilizers for the two most important cereal crops – rice and wheat. Together, these crops provide the bulk of calories consumed in the region. As nitrogen (N) fertilizer is the major source of global warming and other environmental effects, we also examine the factors contributing to its overuse. We applied multiple regression models to understand the factors influencing the use of inorganic fertilizer, Heckman models to understand the likelihood and intensity of organic fertilizer (manure) use, and a probit model to examine the over-use of N fertilizer. Our results indicate that various socio-economic and geographical factors influence the use of organic and inorganic fertilizers in rice and wheat. Across the study sites, N fertilizer over-use is the highest in Haryana (India) and the lowest in Nepal. Across all locations, farmers reported a decline in manure application, concomitant with a lack of awareness of the principles of appropriate fertilizer management that can limit environmental externalities. Educational programs highlighting measures to improving nutrient-use-efficiency and reducing the negative externalities of N fertilizer over-use are proposed to address these problems. | 51480-51496
Afficher plus [+] Moins [-]Changes in spatial patterns of ammonia dry deposition flux and deposition threshold exceedance according to dispersion model formalism and horizontal resolution
2021
Azouz, Niramson | Beekmann, Matthias | Siour, Guillaume | Cellier, Pierre | Drouet, Jean-Louis | Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS) ; AgroParisTech-Université Paris-Saclay-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité) | Institut Pierre-Simon-Laplace (IPSL (FR_636)) ; École normale supérieure - Paris (ENS-PSL) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-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)-École polytechnique (X) ; Institut Polytechnique de Paris (IP Paris)-Institut Polytechnique de Paris (IP Paris)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité) | ANR-12-AGRO-0003,ESCAPADE,Evaluation de Scénarios sur la Cascade de l'Azote dans les Paysages Agricoles et moDElisation territoriale(2012) | European Project: 282910,EC:FP7:ENV,FP7-ENV-2011,ECLAIRE(2011)
International audience | Ammonia (NH 3) emitted into the atmosphere from agricultural sources may affect nearby sensitive ecosystems due to high dry deposition fluxes on vegetation and soil surfaces, contributing to critical load exceedances. Ammonia fluxes near sources are simulated by either short-range atmospheric models or regional models using large grid cell sizes. However, studies are missing on the comparison of the results simulated by these two types of models. This paper presents the effect of model formalism, input factors, especially grid cell size and wind speed and the choice of deposition threshold on the spatial patterns of NH 3 dry deposition fluxes and deposition threshold exceedances. We used the Eulerian chemistry-transport model CHIMERE and the Gaussian plume model OPS-ST on two study domains characterised by contrasting land use. We showed that the average annual NH 3 dry deposition fluxes over each whole domain are similar for both models. By contrast, NH 3 dry deposition fluxes near sources are higher when simulated with OPS-ST that provides analytical solutions that can be sampled with small grid cell sizes (i.e., from 25 to 1600 m in this study), than with CHIMERE, which uses large grid cell sizes (i.e., 800 and 1600 m). As a result, the spatial patterns of deposition threshold exceedance were very different between both models. These patterns depend mainly on grid cell size, the input factors and the choice of the deposition threshold value. We show that the model formalism has a relatively small effect on the results and that the differences result mainly from the spatial resolutions to which they can be applied. Simulation results must therefore be interpreted carefully, taking into account the simulation conditions.
Afficher plus [+] Moins [-]Gathering at the top? Environmental controls of microplastic uptake and biomagnification in freshwater food webs
2021
Krause, Stefan | Baranov, Viktor | Nel, Holly, A | Drummond, Jennifer, D | Kukkola, Anna | Hoellein, Timothy | Sambrook Smith, Gregory, H | Lewandowski, Joerg | Bonet, Berta | Packman, Aaron, I | Sadler, Jon | Inshyna, Valentyna | Allen, Steve | Allen, Deonie | Simon, Laurent | Mermillod-Blondin, Florian | Lynch, Iseult | School of Geography, Earth and Environmental Sciences [Birmingham] ; University of Birmingham [Birmingham] | Équipe 3 - Écologie, Évolution, Écosystemes Souterrains (E3S) ; Laboratoire d'Ecologie des Hydrosystèmes Naturels et Anthropisés (LEHNA) ; Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-École Nationale des Travaux Publics de l'État (ENTPE)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-École Nationale des Travaux Publics de l'État (ENTPE)-Centre National de la Recherche Scientifique (CNRS) | Department of Biology II, Ludwig Maximilians University, Munich ; Department of Biology II, | Loyola University Chicago ; Department of Biology | Department of Ecohydrology ; Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB) | Humboldt-Universität zu Berlin = Humboldt University of Berlin = Université Humboldt de Berlin (HU Berlin) | DEPARTMENT OF CIVIL AND ENVIRONMENTAL ENGINEERING NORTHWESTERN UNIVERSITY EVANSTON USA ; Partenaires IRSTEA ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | University of Strathclyde [Glasgow]
International audience | Microplastics are ubiquitous in the environment, with high concentrations being detected now also in river corridors and sediments globally. Whilst there has been increasing field evidence of microplastics accumulation in the guts and tissues of freshwater and marine aquatic species, the uptake mechanisms of microplastics into freshwater food webs, and the physical and geological controls on pathway-specific exposures to microplastics, are not well understood. This knowledge gap is hampering the assessment of exposure risks, and potential ecotoxicological and public health impacts from microplastics.This review provides a comprehensive synthesis of key research challenges in analysing the envi- ronmental fate and transport of microplastics in freshwater ecosystems, including the identification of hydrological, sedimentological and particle property controls on microplastic accumulation in aquatic ecosystems. This mechanistic analysis outlines the dominant pathways for exposure to microplastics in freshwater ecosystems and identifies potentially critical uptake mechanisms and entry pathways for microplastics and associated contaminants into aquatic food webs as well as their risk to accumulate and biomagnify.We identify seven key research challenges that, if overcome, will permit the advancement beyond current conceptual limitations and provide the mechanistic process understanding required to assess microplastic exposure, uptake, hazard, and overall risk to aquatic systems and humans, and provide key insights into the priority impact pathways in freshwater ecosystems to support environmental man- agement decision making.
Afficher plus [+] Moins [-]The Indian Ocean ‘garbage patch’: Empirical evidence from floating macro-litter
2021
Connan, Maëlle | Perold, Vonica | Dilley, Ben | Barbraud, Christophe | Cherel, Yves | Ryan, Peter | Marine Apex Predator Research Unit (MAPRU) [Port Elizabeth, South Africa] ; Nelson Mandela University [Port Elizabeth] | FitzPatrick Institute of African Ornithology ; University of Cape Town-DST-NRF Centre of Excellence | Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC) ; La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
International audience | Marine litter has become a global issue with ‘garbage patches’ documented in all ocean gyres. The Pacific and Atlantic garbage patches have been well described, but there are few empirical data for the Indian Ocean. In the austral summer 2019–2020, we conducted an at-sea survey of macro-litter in the rarely investigated south-west Indian Ocean. Over 24 days, 1623 man-made items were observed including plastic fragments, packaging and fishing-related items during 216 h of observations covering 5464 km. More than 99% of the litter items were plastics of which almost 60% were white. Floating litter was patchily distributed with only five items (0.2%) recorded south of 40°S (0.1 items·km‐2). Half of the items were encountered over a two-day period south-east of Madagascar (30°S; 59–67°E; 75.2 items·km‐2). Our survey detected an accumulation of litter in the southern Indian Ocean and demonstrated that this area warrants more research.
Afficher plus [+] Moins [-]Experimental and DFT investigation on N-functionalized biochars for enhanced removal of Cr(VI)
2021
Zhao, Nan | Zhao, Chuanfang | Liu, Kunyuan | Zhang, Weihua | Tsang, Daniel C.W. | Yang, Zaikuan | Yang, Xixiang | Yan, Bofang | Morel, Jean Louis | Qiu, Rongliang
International audience | In this study, N-functionalized biochars with varied structural characteristics were designed by loading poplar leaf with different amounts of urea at 1:1 and 1:3 ratios through pyrolysis method. The addition of urea significantly increased the N content of biochar and facilitated the formation of amine (-NH-, -NH2), imine (-HC=NH), benzimidazole (-C7H5N2), imidazole (-C3H3N2), and pyrimidine (-C4H3N2) groups due to substitution reaction and Maillard reaction. The effect of pH on Cr(VI) removal suggested that decrease in solution pH favored the formation of electrostatic attraction between the protonated functional groups and HCrO4-. And, experimental and density functional theory study were used to probe adsorption behaviors and adsorption mechanism which N-functionalized biochars interacted with Cr(VI). The protonation energy calculations indicated that N atoms in newly formed N-containing groups were better proton acceptors. Adsorption kinetics and isotherm experiments exhibited that N-functionalized biochars had greater removal rate and removal capacity for Cr(VI). The removal rate of Cr(VI) on N-functionalized biochar was 10.5-15.5 times that of untreated biochar. Meanwhile, N-functionalized biochar of NB3 with the largest number of adsorption sites for-C7H5N2,-NH2,-OH,-C3H3N2, and phthalic acid (-C8H5O4) exhibited the supreme adsorption capacity for Cr(VI) through H bonds and the highest adsorption energy was -5.01 kcal/mol. These mechanistic findings on the protonation and adsorption capacity are useful for better understanding the functions of N-functionalized biochars, thereby providing a guide for their use in various environmental applications.
Afficher plus [+] Moins [-]The combination of chemical, structural, and functional indicators to evaluate the anthropogenic impacts on agricultural stream ecosystems
2021
Jabiol, Jérémy | Chauvet, Eric | Guérold, François | Bouquerel, Jonathan | Usseglio-Polatera, Philippe | Artigas, Joan | Margoum, Christelle | Le Dréau, Matthieu | Moreira, Aurélie | Mazzella, Nicolas | Gouy, Véronique | Hydrobiologie et Fonctionnement des Ecosystèmes (HYFE) | 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) | Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC) ; Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Terre et Environnement de Lorraine (OTELo) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire Microorganismes : Génome et Environnement (LMGE) ; Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA) | RiverLy - Fonctionnement des hydrosystèmes (RiverLy) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Ecosystèmes aquatiques et changements globaux (UR EABX) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
International audience
Afficher plus [+] Moins [-]An in vitro bioassay to assess the potential global toxicity of waters on spermatogenesis: a pilot study
2021
Blondet, Antonine | Martin, Guillaume | Paulic, Laurent | Perrard, Marie-Hélène | Durand, Philippe | Kallistem SAS ; Partenaires INRAE | Institut cellule souche et cerveau / Stem Cell and Brain Research Institute (SBRI) ; Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
International audience | Many toxicants are present in water as a mixture. Male infertility is one of the environmental impacts in developed countries. Using our rat seminiferous tubule culture model, we evaluated the effects of waters of different origins, on several parameters of the seminiferous epithelium. Concentrated culture medium was diluted with the waters to be tested (final concentrations of the tested waters were between 8 and 80%). The integrity of the blood-testis barrier was assessed by the trans-epithelial electric resistance (TEER). The levels of mRNAs specific of Sertoli cells, of cellular junctions, of each population of germ cells, of androgen receptor, of estrogen receptor α and of aromatase were also studied. We report, here, the results obtained with ten waters, some of them possessing a negative effect on spermatogenesis. The results showed that according to the tested waters, their effects on the parameters studied might be quite different indicating many different mechanisms of toxicity, including some endocrine disrupting effects. It has been reported that men with impaired semen parameters have an increased mortality rate suggesting semen quality may provide a fundamental biomarker of overall male health. Hence, we have developed a relevant in vitro bioassay allowing to evaluate the potential toxicity of different types of waters on male fertility and to assess some aspects of their mechanism of action. In addition to the TEER measure, the number and/or the identity of the studied mRNAs can be largely increased and/or modified, thus enhancing the possibility of using this model as a "warning system".
Afficher plus [+] Moins [-]Non essential element concentrations in brown grain rice : assessment by advanced data mining techniques
2021 | 2017
Villafañe, Roxana Noelia | Hidalgo, Melisa Jazmín | Píccoli, Analía Beatriz | Marchevsky, Eduardo Jorge | Pellerano, Roberto Gerardo
The concentrations of 17 non-essential elements (Al, As, Ba, Be, Cd, Ce, Cr, Hg, La, Li, Pb, Sb, Sn, Sr, Th, Ti, and Tl) were determined in brown grain rice samples of two varieties: Fortuna and Largo Fino. The samples were collected from the four main producing regions of Corrientes province (Argentina). Quantitative determinations were performed by inductively coupled plasma mass spectrometry (ICP-MS), using a validated method. The contents of As, Be, Cd, Ce, Cr, Hg, Pb, Sb, Sn, Th, and Tl were very low or not detected in most samples. The non-essential element levels detected were in line with studies conducted in rice from different parts of the world. In order to characterize the influence of geographical origin in the samples, the following classification methods were carried out: linear discriminant analysis (LDA), k-nearest neighbors (k-NN), partial least squares discriminant analysis (PLS-DA), support vector machine (SVM) and random forests (RF). The best performance was obtained by using RF (96%) and SVM (96%). The results reported here showed the variation in the non-essential element profiles in rice grain depending on the geographical origin.
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