HAL-INERIS
Not a member yet
8807 research outputs found
Sort by
Hazardous properties of brominated, phosphorus, chlorinated, nitrogen and mineral flame retardants in plastics which may hinder their recycling
No full textInternational audienceFlame retardants are numerous and some of them are (re)classified with time as hazardous for the man and the environment. A list of 69 flame retardants used in EU was set from three sources and their chemical properties were searched in their registration dossier at ECHA. Substance self-classifications (hazard statement assignment by the registrant) frequently indicate no hazard or data not available, while for the same substances a re-evaluation by ECHA is underway as persistent, bioaccumulative, toxic or endocrine disruptor. When the substance has hazard statement(s), the concentration that triggers the classification of a plastic as hazardous when it is a waste can be compared to the functional concentration, when available. Registration dossiers should be completed for the many “non-available” information. Of these 69 substances, 12 (= 17%) are used at concentrations greater than those making plastic waste hazardous and 13 (= 19%) are under re-evaluation by ECHA. These 12 or 13 substances should not become “legacy” substances which hinder the recycling of plastics. The sorting (mainly by density) and management options of these flame-retarded plastics are discussed. The technical concentration limit of 2000 mg total Br/kg for sorting should not be modified as it includes all organobromine substances currently reassessed by ECHA. A two-step sorting process is necessary to avoid the loss of non-hazardous dense plastics
Can we compare the excess risk due to carcinogenic substances and the detriment due to ionizing radiation exposure ?
No full textInternational audienc
Acute toxicity, teratogenic and estrogenic activity of test chemicals using a combination of two zebrafish embryosbased assays using the cyp19a1b-GFP line
No full textInternational audienc
Development of a Physiologically-Based Toxicokinetic Model of BPA in Fish Including Its Two Main Metabolites, Bpa-Glucuronide and Bpa-Sulfate
No full textInternational audiencePhysiologically-based toxicokinetic models (PBTK) are useful tools to improve understanding of the fate of a chemical inside an organism. Recently, Grech et al. (2019) proposed a generic PBTK model for four different fish, including zebrafish (Danio rerio), threespine stickleback (Gasterosteus aculeatus), rainbow trout (Oncorhynchus mykiss) and fathead minnow (Pimephales promelas). Meanwhile, bisphenol A (BPA) is considered as very high concern substance due to its endocrine disruptor function, its high production volume and its persistence in the aquatic environment. In this work, the PBTK will be adapted to accurately model the ADME processes (absorption, distribution, metabolization and excretion) of BPA. A particular effort will be carried out to predict internal concentration of its two main metabolites, BPA-monoglucuronide (BPA-g) and BPA-monosulfate (BPA-s), in various organs. In vitro data from zebrafish, rat (Sprague-Dawley) and mouse (CD-1) hepatocytes will be used to calculate Michaelis-Menten parameters related to metabolism. Moreover, TK data in zebrafish and rainbow trout for BPA, BPA-G and BPA-S in different organs will be retrieved from literature to calibrate the model. The objective will be to accurately predict TK data measured in vivo in external datasets. Further development will later add TD sub-models to predict the dynamic of biomarkers measured in organs
Per- and Polyfluoroalkyl Substances (PFAS) in Surface Sediments: Occurrence, Patterns, Non-Physical Drivers and Contribution of Unidentified Precursors in French Aquatic Environments
No full textInternational audienceSediment acts as a sink for per- and polyfluoroalkyl substances (PFAS), especially for perfluoroalkyl sulfonic acids (PFSAs) and perfluoroalkyl carboxylic acids (PFCAs). Recently, non-targeted methods have shown the presence of numerous unknown PFAS in environmental samples. The contribution of these PFAS can be estimated by the Total Oxidisable Precursor assay (TOP), an oxidative method used to convert polyfluoroalkyl precursors (pre-PFAAs) into perfluoroalkyl acids (PFAAs). While sediment properties (grain size and organic carbon fraction, foc) were reported as controlling factors for some PFAS, the influence of non-physico-chemical drivers (e.g. population density) still needs to be investigated. Thus, this work focused on sediments from France and used optimized analytical methods and geographical information system (GIS) to fill these knowledge gaps. Extraction solvent was modified from methanol (MeOH) + ammonium hydroxide to MeOH + ammonium acetate for the analysis of 16 PFAAs, 6 alternative PFAAs and 14 pre-PFAAs covering anionic, neutral and zwitterionic species (n:2 fluorotelomer sulfonamidoalkyl betaines, n:2 FTABs). The optimized method exhibited suitable performances for its application on sediments (n=50) collected in 2018. The TOP assay was adapted to this specific method extraction. Perfluorododecanic acid,perfluorooctane sulfonic acid (PFOS) as well as perfluorooctanoic acid (PFOA) were often detected (76, 74 and 68 % respectively). 6:2 FTAB, 8:2 FTAB and perfluoropentyl propanoic acid (FPePA) were also detected (38, 26 and 36 %, respectively). Median ∑PFAS was 1.3 ng.g-1 dry weight (dw) (range < LOD–23 ng.g-1 dw). 6:2 FTAB and 8:2 FTAB levels ranged from < 0.36 to 6.4 ng.g-1 dw and < 0.50 to 7.4 ng.g-1 dw, which is in the same order of magnitude than L-PFOS (< 0.08–5.1 ng.g-1 dw) advocating for the necessity to include these PFAS in targeted analysis. At nationwide scale, PFOS and ∑PFCAs accounted for 37 ± 25% and 31 ± 21% of ∑PFAS, respectively, while targeted pre-PFAAs accounted for 29 ± 27%, thereby supporting the importance of the latter in sediment and the potential contribution of untargeted pre-PFAAs monitored by the TOP assay (data under acquisition). Correlations between PFAS levels normalized by foc, unidentified pre-PFAAs and non-physico-chemical drivers with GIS are being investigated. Preliminary results showed that PFAS levels were not correlated with sample site position in the hydrographic system (proxy: Strahler number)
Mise en évidence de marqueurs moléculaires de sources primaires et secondaires de particules atmosphériques : intérêt de l'approche analytique non ciblée par spectrométrie de masse haute résolution
No full textThe impact of particulate matter (PM, aerosols) on air quality is widely recognized and the implementation of measures to reduce their concentrations in ambient air requires knowledge of their origins. The study of the PM sources can be achieved by monitoring molecular markers or chemical signatures used in statistical source-receptor models. However, some sources remain unresolved due to the lack of specific molecular markers. High resolution mass spectrometry (HRMS) provides a means to obtain a more complete characterization of environmental matrices. Non-target screening (NTS) approaches combined with multivariate statistical analysis allow a comparison of sample chemical fingerprints to highlight substances of interest. The objective of this thesis was to evaluate the potential of the chemical fingerprinting approach to identify specific molecular markers of currently unresolved PM sources. Two sources of PM were studied because of their important contributions to the observed ambient air concentrations: biomass combustion and vehicular emissions. The objective was to distinguish between residential wood burning and green waste burning (garden fires) and to discriminate between primary and secondary sources of PM from light-duty diesel and gasoline vehicle emissions. Different tests under controlled real conditions were performed to collect PM samples from the two targeted sources. Biomass combustion tests, residential wood heating (fireplace, log stove) and green waste burning (hedge trimmings, fallen leaves), were performed in a large combustion chamber to simulate real ambient air dilution conditions. Vehicular samples were obtained from chassis dynamometer tests with two current-in-use (EURO 5 standard) gasoline and diesel vehicles. Their emissions were also aged in an oxidation reactor to simulate photochemical processes (with OH radical) taking place in the atmosphere. The work was based on chemical characterization using targeted and non-targeted analytical methods using HRMS coupled with liquid- and gas- chromatography (LC and GC). In addition to evaluate emission factors of particulate species of interest emitted from green waste burning, results obtained from targeted analyses highlighted indicators of both biomass combustion sources (carbon preference index, levoglucosan/mannosan ratio, sinapylaldehyde, erythritol and sorbitol abundances) which was ultimately not specific enough to allow their clear discrimination in ambient air. From multivariate statistical analyses (e.g. partial least squares discriminant analysis (PLS-DA) and clustering analysis) of NTS data obtained by LC- and GC-HRMS, about thirty entities specific to green waste burning and four to residential wood heating, were highlighted and some of them could be identified. Similarly, about ten chemical entities of each the primary and secondary emissions of gasoline and diesel vehicles could be determined. This work has shown the potential of the NTS approach and the chemical fingerprinting to highlight chemical entities of atmospheric interest and in particular markers of PM sources. In the long term, they could be used in studies of PM sources in ambient air.L'impact délétère des particules (PM, aérosols) sur la qualité de l'air est largement reconnu et la mise en place de mesures de réduction de leurs concentrations dans l'air ambiant requiert de connaitre leurs origines. L'étude des sources des PM peut être réalisée à partir du suivi de composés marqueurs ou de signatures chimiques utilisés dans des modèles statistiques sources-récepteurs. Cependant, certaines sources demeurent non résolues actuellement par manque de marqueurs moléculaires spécifiques. La spectrométrie de masse haute résolution (HRMS) apporte un moyen d'obtenir une caractérisation plus complète des matrices environnementales. Par ce biais, les approches d'analyses non-ciblées (non-target screening, NTS) combinées à des analyses statistiques multivariées, permettent de réaliser une comparaison d'empreintes chimiques d'échantillons afin de mettre en évidence des substances d'intérêt. Ainsi, l'objectif de ce travail de thèse était d'évaluer le potentiel de l'approche de comparaisons d'empreintes chimiques afin de mettre en évidence des marqueurs moléculaires spécifiques de sources de PM non résolues actuellement. Deux sources de PM ont été étudiées compte tenu de l'importance de leurs contributions sur les concentrations observées dans l'air ambiant : la combustion de biomasse et les émissions véhiculaires avec pour objectif d'une part, la distinction du chauffage résidentiel au bois et du brûlage à l'air libre de déchets vert (feux de jardin) et d'autre part, la discrimination des sources de PM primaires et secondaires provenant des émissions de véhicules routiers légers diesel et essence. Différents essais en conditions réelles contrôlées ont été réalisés afin de collecter des échantillons de PM des deux sources ciblées. Les essais de combustion de biomasse, chauffage résidentiel au bois (cheminée, poêle bûches) et brûlage à l'air libre de déchets verts de jardin (tailles de haies, feuilles mortes), ont été réalisés dans une large chambre de combustion permettant de simuler les conditions réelles de dilution de l'air ambiant. Les échantillons véhiculaires ont été obtenus à partir d'essais sur banc à rouleaux avec deux véhicules modernes (norme EURO 5) essence et diesel. Leurs émissions ont également été vieillies au moyen d'un réacteur d'oxydation permettant de simuler les processus photochimiques (réactivé avec le radical OH) ayant lieu dans l'atmosphère. Le travail était basé sur une caractérisation chimique au moyen de méthodes d'analyses ciblées et non ciblées utilisant la HRMS couplée à la chromatographie en phase liquide et gazeuse (LC et GC). Outre l'évaluation des facteurs d'émission d'espèces particulaires d'intérêt émises par le brûlage de déchets verts, les résultats obtenus à partir des analyses ciblées ont permis de mettre en avant des indicateurs des deux sources de combustion de biomasse (indice de parité des alcanes, rapport lévoglucosan/mannosan, abondance du sinapylaldéhyde, érythritol et sorbitol) mais finalement pas assez spécifiques pour permettre leur discrimination claire dans l'air ambiant. A partir d'analyses statistiques multivariées (e.g. analyse discriminante par les moindres carrés partiels (PLS-DA) et analyse de regroupement) des données NTS obtenues par LC- et GC-HRMS, une trentaine d'entités ou composés chimiques spécifiques du brûlage à l'air libre de déchets verts de jardin et quatre du chauffage résidentiel au bois, ont été mis en évidence et dont certains ont pu être identifiés. De façon similaire, une dizaine d'entités chimiques singulières de chacune des émissions primaires ou secondaires des véhicules essence et diesel ont pu être déterminées. Ce travail a permis de montrer le potentiel de l'approche NTS et de la comparaison d'empreintes chimiques afin de mettre en évidence des entités chimiques d'intérêt atmosphériques et notamment marqueurs de sources de PM. A terme, elles pourront être utilisées lors d'études de sources de PM dans l'air ambiant
Evaluation of new 4D-variational inverse modeling system, CIF-CHIMERE: Inversion of NOx emissions over China using NO2 OMI observations
No full textInternational audienc
Caractérisation du comportement mécanique de matériaux isolants sous choc
No full textRisk reduction on Seveso sites and their surroundings, especially for the protection of industrial buildings in the event of an explosion scenario, is a matter of concern. In the context where the insulation of industrial buildings is becoming more widespread, one solution would be to combine thermal insulation and building protection, by exploiting the absorption capacity of common thermal insulating materials. This solution would be interesting from an economic point of view.The aim of this PhD thesis is to characterise experimentally the mechanical behaviour of two insulating materials: a polyisocyanurate foam and a glass wool. The mechanical characterisation for dynamic loadings of these kinds of complex materials with very-low densities remains vastly incomplete to this day.Unconfined and confined compression experiments in static loading are carried out and a follow-up using high-resolution imaging associated with digital image correlation allows to identify the mechanical properties, to observe the heterogeneity of the strain field and to follow the propagation of compaction fronts in the material.Dynamic compression experiments using the Split Hopkinson Pressure Bars device (SHPB), completed with DMA experiments, allow to study the strain rate sensitivity of the response and to highlight a strain rate dependence of the plateau stress and an insensitivity to the strain rate at densification. A high-speed imaging follow-up associated with digital image correlation also allows to observe the heterogeneity of the strain field and to determine the speed of the compaction front in the material.The mechanical behaviour of the insulating materials is described using empirical laws or rheological solid models. A simplified model is proposed to analyse the potential effect of a protection device composed of a cladding and a thermal insulating material against a shockwave loading. It shows that if a protection effect is possible, its effectiveness will depend on the signature of the shock loading and the physical and geometrical characteristics of the protection system.La réduction des risques, sur des sites Seveso et leurs alentours, face aux sollicitations accidentelles ou malveillantes, passe par la sécurisation des bâtiments aux sollicitations dynamiques de type surpression et impact. L’utilisation d’une isolation par l’extérieur, de type matériau isolant et bardage métallique par exemple, semble une piste intéressante techniquement et économiquement permettant d’allier protection face aux risques technologiques et rénovation énergétique.Dans ce travail, deux matériaux représentatifs des isolants thermiques plastiques et minéraux ont été retenus, une mousse polyisocyanurate et une laine de verre. La caractérisation mécanique de ce type de matériaux complexes et à très faible masse volumique demeure, dans le contexte de sollicitations dynamiques, largement incomplète à l’heure actuelle et les essais mal maîtrisés.Des essais de compression simple et œdométrique en régime statique sont réalisés et un suivi par imagerie à haute résolution associé à de la corrélation d’images numérique permet d’identifier les propriétés mécaniques, d’observer l’hétérogénéité des déformations et de suivre la propagation de fronts de compaction dans le matériau.Des essais dynamiques aux barres de Hopkinson, complétés d’essais DMA, permettent d’étudier la sensibilité à la vitesse de la réponse et de mettre notamment en évidence une dépendance à la vitesse de la contrainte plateau et une insensibilité à la vitesse de la déformation à la densification. Un suivi par imagerie à haute vitesse associé à de la corrélation d’images numérique permet également d’observer l’hétérogénéité des déformations et de déterminer la célérité du front de compaction dans le matériau.Le comportement mécanique des isolants est reproduit au moyen de lois empiriques ou par assemblage de modèles rhéologiques. Une modélisation simplifiée est proposée pour analyser l’effet potentiel d’un dispositif de protection constitué d’un ensemble bardage et isolant face à une sollicitation dynamique transitoire. Elle montre que si un effet atténuateur est possible, son efficacité va dépendre tout à la fois de la signature de la sollicitation et des caractéristiques physiques et géométriques du système de protection
Underground Rock Dissolution and Geomechanical Issues
No full textInternational audienceMany soluble rocks will dissolve when in contact with fluid such as water. This transformation of rock solid into flowing fluid may trigger the creation of cavities which may further lead to either smooth subsidence or sudden collapse of land surface. Dissolution phenomenon can be of natural or human origin. This paper deals with the problem of the dissolution of underground soluble rocks and the geomechanical consequences such as subsidence, sinkholes and underground collapse. In this paper, rock dissolution and the induced underground cavities are computed using a Diffuse Interface Model, which does not require to follow interfaces explicitly. We describe briefly the mathematical and physical framework for the dissolution model. We first explain the transition (upscaling) of a multiphysics problem formulated at the microscopic (pore-) scale level to the macroscopic (Darcy-) scale level. Rock material considered in this paper is gypsum, despite that the developed method is also suitable for over soluble rocks (e.g., limestone, Halite). The second part of this paper is devoted to a set of problems dealing with mechanical response of the rock mass in connection with the dissolution process. We discuss the subsidence induced by the dissolution of one or more gypsum lenses, the stability of the covering, and finally the failure of a gypsum pillar in an abandoned quarry. These examples, while they may involve rather theoretical hypotheses, have the virtue of showing the relevance of the method as well as the very diverse issues that it can treat
Towards a qAOP framework for predictive toxicology - Linking data to decisions
No full textInternational audienceThe adverse outcome pathway (AOP) is a conceptual construct that facilitates organisation and interpretation of mechanistic data representing multiple biological levels and deriving from a range of methodological approaches including in silico, in vitro and in vivo assays. AOPs are playing an increasingly important role in the chemical safety assessment paradigm and quantification of AOPs is an important step towards a more reliable prediction of chemically induced adverse effects. Modelling methodologies require the identification, extraction and use of reliable data and information to support the inclusion of quantitative considerations in AOP development. An extensive and growing range of digital resources are available to support the modelling of quantitative AOPs, providing a wide range of information, but also requiring guidance for their practical application. A framework for qAOP development is proposed based on feedback from a group of experts and three qAOP case studies. The proposed framework provides a harmonised approach for both regulators and scientists working in this area