Les zones humides construites et l'épuration des eaux drainées agricoles : Suivi d'un site témoin. Convention 2008-2010 (Rapport intermédiaire)

[Departement_IRSTEA]Eaux [TR1_IRSTEA]ARCEAULe projet du Cemagref porte sur les zones humides construites (ZHC) ou restaurées pouvant être utilisées comme ouvrages compensateurs (ou atténuateurs de l'impact) de l'activité agricole en milieu rural sur les bassins versants amonts pour diminuer voire éliminer les transferts de contaminants par les eaux de surface jusqu'au milieu récepteur. Les expérimentations porteront dans un premier temps sur les eaux issues du drainage agricole qui présente l'avantage de concentrer les eaux en un point donné (maîtrise hydraulique pour le traitement dans les ZHC) mais qui tend à court-circuiter le cheminement naturel de l'eau à travers des zones réputées 'épuratrices' du paysage, comme les zones ripariennes. Plusieurs axes de travail ont été dégagés : Quel est le devenir des polluants d'origine agricole (pesticides, nutriments) dans ces zones humides ? Quelle est la part de l'eau captée par le drainage, qui peut être dirigée vers ces ZHC, et celle qui s'infiltre sous le drainage ? Quelle stratégie d'optimisation adopter (gestion hydraulique par l'agriculteur, aménagement des bassins, apport de substrat) pour optimiser le fonctionnement d'une telle zone, en termes d'épuration des eaux ? Le présent projet apportera des éléments quantifiés sur les deux premières questions et servira pour la réflexion concernant le dernier point

Elucidation of the thermophilic phenol biodegradation pathway via benzoate during the anaerobic digestion of municipal solid waste

International audienceAnaerobic digestion makes it possible to valorize municipal solid waste (MSW) into biogas and digestate which are, respectively, a renewable energy source and an organic amendment for soil. Phenols are persistent pollutants present in MSW that can inhibit the anaerobic digestion process and have a toxic effect on microbiota if they are applied to soil together with digestate. It is then important to define the operational conditions of anaerobic digestion which allow the complete degradation of phenol. In this context, the fate of phenol during the anaerobic digestion of MSW at 55 °C was followed using an isotopic tracing approach (13C6-phenol) in experimental microcosms with inoculum from an industrial thermophilic anaerobic digester. With this approach, it was possible to demonstrate the complete phenol biodegradation into methane and carbon dioxide via benzoate. Benzoate is known to be a phenol metabolite under mesophilic conditions, but in this study it was found for the first time to be a phenol degradation product at thermophilic temperature

Curative treatment can be an option for patients with metastatic squamous cell cancer of the head and neck

Clémence Guenne,1 Jérôme Fayette,2 Alain Cosmidis,1 Carine Fuchsmann,1 Sophie Tartas,3 Véronique Favrel,4 Philippe Céruse1 1Head and Neck Surgery Department, Lyon-I University, Hospices Civils de Lyon, Lyon Sud Hospital, Pierre-Bénite, France; 2Medicine Department, Lyon-I University, Centre Léon Bérard, Lyon, France; 3Medical Oncology Department, Lyon-I University, Hospices Civils de Lyon, Lyon Sud Hospital, 4Radiotherapy Department, Lyon-I University, Hospices Civils de Lyon, Lyon Sud Hospital, Pierre-Bénite, France Background: No specific study has focused on patients with metastatic squamous cell carcinoma of the head and neck (SCCHN) at diagnosis. Due to high response rates of induction chemotherapy in chemo-naïve patients with localized disease, their prognosis should be better than patients with recurrent disease.Methods: From January 1, 2008 to July 1, 2012, we retrospectively collected all patients’ records with SCCHN diagnosed as metastatic. Patients, disease, treatment and its results were analyzed. Survival was calculated using the Kaplan–Meier method.Results: Of the 749 new patients treated for SCCHN in our institution, 16 (2.1%) were metastatic at diagnosis, of whom five had cytological results to prove it. Six patients died before treatment or had palliative care and ten received initial chemotherapy and then surgery and/or radiotherapy according to the primary response. Four patients treated with first-line chemotherapy with docetaxel-5FU-cisplatin (TPF) showed a complete response of metastatic lesions allowing locoregional treatment. The overall survival at 1 year and 3 years was 50% and 24%, respectively. The median survival was 7 months (1–72 months). Seven patients (43.7%) had a higher survival at 12 months, including five (31.5%) who are still alive without recurrence with a mean follow-up of 30 months. There was a significant difference in overall survival (P<0.01) between patients who had chemotherapy with TPF versus other therapeutic protocols. The median survival of patients with lung metastases only was 15 months (1–72 months), significantly higher than that of patients with liver and/or bone localizations, which was 2 months (1–9 months).Conclusion: Patients with metastatic SCCHN treated by TPF followed by multimodal treatment could achieve long survival. Keywords: squamous cell carcinoma, head and neck, metastases, TPF, cetuxima

Zones humides - épuration des eaux de drainage : Synthèse des travaux de la convention n°105195 Période 2008-2010

[Notes_IRSTEA]Ce document est une synthèse du rapport de l'étude transmis à l'AESN. [Departement_IRSTEA]Eaux [TR1_IRSTEA]ARCEAULe drainage agricole s'est fortement répandu dans les années 80 comme moyen de modernisation de l'agriculture française. Il a d'ailleurs fait l'objet de travaux de recherche sur son optimisation dans le contexte français. Depuis les années 90 et 2000, ce sont ces impacts qui font l'objet de controverses : impact quantitatif sur les crues et qualitatif sur la qualité de l'eau. Les travaux présentés dans cette synthèse porte sur la réduction des transferts de contaminant d'origine agricole (nitrate et pesticide) dans les eaux de drainage avant de rejoindre le réseau hydrographique. Ainsi nous avons exploré et évalué la piste des zones tampons humides artificielles. Nous définissons une zone tampon humide artificielle comme étant une surface non agricole, parfois prise sur une terre agricole, recevant de façon temporaire des eaux agricoles, et assurant un rôle de filtre, de réacteur biologique favorable à la dissipation des contaminants agricoles. Dans la littérature, un ratio de surface de l'ordre de 1% de la surface contributive apparaît comme un compromis réaliste, mais c'est un point à développer. Au travers des différents travaux du Cemagref sur les zones tampons humides artificielles, nous étudions le cas spécifique d'un bassin de rétention dont la vocation première est le stockage d'eau en vue d'irrigation mais dont la capacité de dissipation est réelle

Identification et impact écotoxicologique des composés chimiques extraits de géomembranes situées dans les zones agricoles

10èmes Rencontres Géosynthétiques, La Rochelle, FRA, 24-/03/2015 - 26/03/2015International audienceL'étanchéité des ouvrages hydrauliques est assurée par des géomembranes dont la durée de vie et la maniabilité sont améliorées par l'ajout d'additifs. Cependant, au cours du temps ces additifs sont extraits vers le milieu environnant. En fonction de leur structure, les molécules extraites sont des sources potentielles de contamination des nappes phréatiques et des sols. Les analyses par spectrométries UV et infrarouge et chromatographie gazeuse couplée à une spectrométrie de masse de GMB en polyethylène haute densité (PEHD) et polypropylène (PP) ont mis en évidence la présence d'antioxydants phénoliques et phosphites. Après 11 jours d'immersion dans des milieux aqueux à pH 6,8 et à pH 4,1 (pH moyens des sols français) à 80°C une extraction des anti oxydants est mise en évidence. De plus, des tests d'écotoxicité sur les solutions d'immersion après 96 jours à pH 6,8 montrent une inhibition de l'activité biologique plus importante pour la GMB en PP que pour celle en PEHD

Biodégradation du Penta- et 2,4,6-tri-chlorophenol durant la digestion anaérobie des déchets non dangereux

International audienceIn this study isotopic tracing using C-13 labelled pentachlorophenol (PCP) and 2,4,6-trichlorophenol (2,4,6-TCP) is proposed as a tool to distinguish the loss of PCP and 2,4,6-TCP due to biodegradation from other physical processes. This isotopic approach was applied to accurately assess in situ PCP and 2,4,6-TCP degradation under methanogenic conditions in several microcosms made up of household waste. These microcosms were incubated in anaerobic conditions at 35 degrees C (mesophilic) and 55 degrees C (thermophilic) without agitation. The volume of biogas produced (CH4 and CO2), was followed for a period of 130 days. At this stage of stable methanogenesis, C-13(6)-PCP and C-13(6)-2,4,6-TCP were introduced anaerobically in microcosms and its monitoring at mesophilic and thermophilic conditions was performed in parallel by gas chromatography mass spectrometry (GC-MS) and gas chromatography isotope-ratio mass spectrometry (GC-IRMS). This study proved the almost total dechlorination of bioavailable PCP and 2,4,6-TCP into 4-CP at 35 degrees C. Nevertheless, high rate adsorption in particular materials of the two compounds was observed. Furthermore, Carbon-13 Nuclear Magnetic Resonance (C-13-NMR) Spectroscopy analysis of C-13 labelled 2,4,6-TCP mesophilic incubations showed the partial mineralization of 4-CP at 35 degrees C to acetate and then to HCO3-. Consequently, NMR results confirm the biogas isotopic results indicating the mineralization of C-13 labelled 2,4,6-TCP into C-13 (CH4 and CO2). Concerning C-13 labelled PCP mesophilic incubations, the isotopic composition of the biogas still natural until the day 262. In contrast, no de chlorination was observed at 55 degrees C. Thus PCP and 2,4,6-TCP were persistent in thermophilic conditions

Impact potentiel des additifs des géomembranes sur les écosystèmes - IMAGES

International audienceA variety of geomembranes is widely used in hydraulic applications. Some of the additives included in the manufacturing process will be extracted from the geomembrane after contact with water or a soil. Depending on their chemical nature, additives or their degradation products represent a possible source of impact on natural ecosystems. The paper present the objectives of the research program IMAGES (IMpact of ADditives in GEomembraneS) aiming at quantifying the potential impact of additives extracted from geomembranes installed in hydraulic applications. The methodology consists in identifying the additives contained in HDPE and PP Geomembranes, the additives that can be extracted following various environmental conditions, the additives degradation products, developing a model for additives extraction/diffusion from/through geomembranes and evaluating the potential toxicity of the additives extracted through ecotoxicity tests. Details on the selected protocol are given. The UV spectrometry analyses of the immersion solutions at 82°C evidence an acceleration of hindered phenol AO type degradation products extraction with the acidity of the medium. The small decrease in the OIT value after 96 days at 82°C of the HDPE GM shows that, depending on the ecotoxicity threshold determined, the alert value of AO nocivity will have to be determined with an accurate technique like UV spectrometry

Impact des molécules extraites de géomembranes sur l'activité des micro-organismes en milieux aqueux

National audienceSome additives contained in GMs used for hydraulic applications are extracted to water or soil. To evaluate the ecotoxicological impacts of these chemical compounds on the environment, polypropylene ( PP ) and high density polyethylene (H P D E ) GMs are immersed in aqueous solutions (pH 4 and 7) at 80, 55 and 25°C. At various times intervals, effects of the extracted solutions on microorganisms are evaluated. Ecotoxicological tests highlight negative effects of the first 11 days extracted molecules on micro algae growth and microcrustacean behavior. However, after prolonged exposure, microalgae growth is stimulated. These results may be related to the change of the chemical nature of the molecules detected by UV spectroscopy.Certains additifs ajoutés aux GMB (Géomembranes) utilisées pour l'étanchéité des ouvrages hydrauliques sont extraits vers le milieu environnant (eau et sol). Afin d'évaluer l'impact écotoxicologique de ces composés chimiques sur le milieu, des GMB en polypropylène (PP) et polyéthylène haute densité (PEHD) sont immergées dans des solutions aqueuses à pH 4,3 et 6,7, et à 80, 55 et 25°C. À différentes échéances, les effets des solutions d'extraction sur le comportement des micro-organismes sont évalués. Les tests d'écotoxicité montrent que les molécules extraites les 11 premiers jours nuisent à la croissance des micro-algues et au comportement des micro-crustacés, alors qu'une exposition prolongée stimule la croissance des micro-algues. Ces résultats sont reliés à un changement de la nature chimique des molécules extraites observé par spectrométrie UV

Stable isotope probing of acetate fed anaerobic batch incubations shows a partial resistance of acetoclastic methanogenesis catalyzed by Methanosarcina to sudden increase of ammonia level

ISI Document Delivery No.: CB3BQHao, Liping Lue, Fan Mazeas, Laurent Quemener, Elie Desmond-Le Madigou, Celine Guenne, Angeline Shao, Liming Bouchez, Theodore He, PinjingAmmonia inhibition represents a major operational issue for anaerobic digestion. In order to refine our understanding of the terminal catabolic steps in thermophilic anaerobic digestion under ammonia stress, we studied batch thermophilic acetate fed experiments at low (0.26 g L-1) and high (7.00 g L-1) Total Ammonia Nitrogen concentrations (TAN). Although methane production started immediately for all incubations and resulted in methane yields close to stoichiometric expectations, a 62-72% decrease of methanogenic rate was observed throughout the incubation at 7.00 g L-1 of TAN compared to 0.26 g L-1. Stable Isotope Probing analysis of active microbial communities in C-13-acetate fed experiments coupled to automated ribosomal intergenic spacer analysis and 16S rDNA pyrotag sequencing confirmed that microbial communities were similar for both TAN conditions. At both TAN levels, the C-13-labeled bacterial community was mainly affiliated to Clostridia-relatives, with OPB54 bacteria being the most abundant sequence in the heavy DNA 16S rDNA pyrotag library. Sequences closely related to Methanosarcina thermophila were also abundantly retrieved in the heavy DNA fractions, showing that this methanogen was still actively assimilating labeled carbon from acetate at free ammonia nitrogen concentrations up to 916 mg L-1. Stable isotopic signature analysis of biogas, measured in unlabele