HAL-INERIS
Not a member yet
8807 research outputs found
Sort by
Assessment of Inflammation in 3D Reconstructed Human Skin Exposed to Combined Exposure to Ultraviolet and Wi-Fi Radiation
No full textInternational audienceIn the human environment, the increasing exposure to radiofrequency (RF) radiation, especially that emitted by wireless devices, could be absorbed in the body. Recently, mobile and emerging wireless technologies (UMTS, DECT, LTE, and Wi-Fi) have been using higher frequencies than 2G GSM systems (900/1800 MHz), which means that most of the circulating RF currents are absorbed into the skin and the superficial soft tissue. The harmful genotoxic, cytotoxic, and mutagenic effects of solar ultraviolet (UV) radiation on the skin are well-known. This study aimed at investigating whether 2422 MHz (Wi-Fi) RF exposure combined with UV radiation in different sequences has any effect on the inflammation process in the skin. In vitro experiments examined the inflammation process by cytokines (IL-1α, IL-6, IL-8) and MMP-1 enzyme secretion in a 3D full-thickness human skin model. In the first study, UV exposure was immediately followed by RF exposure to measure the potential additive effects, while in the second study, the possible protective phenomenon (i.e., adaptive response) was investigated when adaptive RF exposure was challenged by UV radiation. Our results suggest that 2422 MHz Wi-Fi exposure slightly, not significantly increased cytokine concentrations of the prior UV exposure. We could not detect the adaptive response phenomenon
The Heterogeneous Effects of Lockdown Policies on Air Pollution
No full textWhile a sharp decline in air pollution has been documented during early Covid-19 lockdown periods, the stability and homogeneity of this effect are still under debate. Building on pollution data with a very high level of resolution, this paper estimates the impact of lockdown policies on P M 2.5 exposure in France over the whole year 2020. Our analyses highlight a surprising and undocumented increase in exposure to particulate pollution during lockdown periods. This result is observed during both lockdown periods, in early spring and late fall, and is robust to several identification strategies and model specifications. Combining administrative datasets with machine learning techniques, this paper also highlights strong spatial heterogeneity in lockdown effects, especially according to long-term pollution exposure
Differential toxicological potential of the main sources contributing to the particle pollution events observed in France
No full textInternational audienceThe negative impact on health of atmospheric particles (aerosols or particulate matter, PM) at the pulmonary, cardiovascular, and neurological levels is widely recognized. However, the understanding of the PM toxicity emitted from different emission sources and the links with their chemical composition are still poorly known. This is especially the case for sources mainly involved in PM pollution episodes (ie. > 50 µg m-3 of PM10 for several consecutive days). In France, and also in Europe, secondary formation of ammonium nitrate and sulfate (late winter -early spring), biomass burning (in winter, mainly due to residential wood heating), and desert dust (e.g. Saharan dust impacting the French West Indies), account for the main contributors during such episodes (Favez et al., 2021). In such context, the main objective of the SOTOX project is to make a comparison of the toxic potential induced by the predominant sources involved in the episodes of particulate pollution observed in France. Biomass combustion sources (primary emissions) and Saharan dust are therefore targeted in the first place. The originality of the work is to propose a differentiated assessment of the toxic potential of various PM sources based on acellular, biological (cellular in vitro) tests, together with an extensive chemical characterization, using PM samples collected during experiments performed in simulated real-world conditions or in ambient air.A set of PM samples collected on filters (n = 80), through different research projects allowed covering the following PM emissions sources:(a) Primary emissions from residential heating: open fireplace, old (5*) logwood stove, modern (7*) logwood/pellet stoves/boilers, oil boiler; tested under different output conditions (nominal and reduced) and using different wood species (hard and softwood),(b) Garden green waste burning (falling leaves, hedge trimming),(c) Desert dust (Saharan episodes in Martinique).The intrinsic PM toxicological potential (/ µg of PM) has been assessed by measuring different toxicity indicators from filter extracts (organic solvent or artificial pulmonary fluid). The acellular oxidative potential (OP) of the PM was determined using different specific probes (ascorbic acid (AA) and dithiothreitol (DTT)). Oxidative/nitrosative stress induction was investigated on human lung cells (A549) using the H2DCFDA (2′,7′-Dichlorodihydrofluorescein diacetate) probe. A bio-analytical approach based on the measurement of the activation of the AhR receptor (aryl hydrocarbon receptor) in human liver cells (HepG2) exposed to PM extracts permitted to evaluate the content of the particles in dioxin- and HAP-like pollutants. In addition, the analysis of key particulate toxic species (metals, polycyclic aromatic hydrocarbons (PAHs)) and their nitrated and oxygenated derivatives), as well as the PM carbonaceous content (elemental and organic carbon, EC-OC), has been performed to study the links between toxicity indicators and PM chemical composition. Results obtained will be compared in terms of intrinsic PM toxicological potential according to the sources, toxicity indicators and PM chemical composition.This work has been performed within the framework of the SOTOX project funded by the French air quality penalt
Post-Mining Risk Management in France and multi-hazard approaches for coal mines
No full textInternational audienceAfter centuries of intensive exploitation of its mineral resources, French mining sites have gradually closed. However, after mine-closure and during the “post-mining” phase, numerous residual hazards can occur — sometimes as soon as mining works stop, or later, such as: ground movement phenomena (subsidence, collapses), rising gas, irreversible disruptions in underground water circulation induced by mining can potentially cause disturbances, both in terms of water circulation (flooding in low areas, disruption of waterway flows) and water quality (pollution). To manage hazards and risks associated with these undesirable events, the French State has several technical and regulatory tools at its disposal. These tools make it possible to compile the available knowledge on residual mining risks related to former mining sites for a given territory, to delimit the affected areas and to define the conditions of construction, occupation, and use of land as well as measures relating to the organization, use or exploitation of existing assets in a context of a sustainable land planning management. This paper presents the methodology to assess the post-mining hazards assessment. The paper also focuses on the development of new methodology for multi-hazards analysis regarding post-mining, natural and technologic hazards. The methodology analyses the hazards interactions and consequences on the environment. The multi-hazards assessment methodology consists of three steps: the identification of the singles hazards, the identification of the hazard interactions and finally the identification of the level and the consequences of the interactions. The matrix tool and interaction organigrams are used to identify the potential interactions. Three levels of interaction are considered: simple interaction, double interaction and dominos or cascading interactions. The natural and mining flooding hazard seems as the main hazard that can trigger several mining hazards: such as ground movement (subsidence, landslide, gas production, etc.)
Implementation of a parallel reduction algorithm in the GENerator of reduced Organic Aerosol mechanisms (GENOA v2.0): Application to multiple monoterpene aerosol precursors
No full textInternational audienceExplicit gas-phase chemical mechanisms represent the state of knowledge regarding the chemistry of volatile organic compounds (VOCs), which are crucial in the formation of secondary organic aerosols (SOAs). However, these chemical mechanisms are computationally expensive, which limits their practical use in large-scale air quality modeling. Mechanism reduction is therefore required for computational efficiency while preserving the accuracy of the detailed gas-phase chemical mechanisms.This paper presents a new version of the Generator of Reduced Organic Aerosol Mechanisms (GENOA v2.0), which reduces mechanisms at a size suitable for three-dimensional (3-D) modeling while preserving the accuracy of detailed chemical mechanisms for simulating aerosol concentrations. GENOA v2.0 adopts a parallel reduction framework to identify the most optimal reductions from competitive candidates, and can reduce chemical mechanisms from multiple aerosol precursors. To demonstrate the reduction efficiency, GENOA v2.0 is applied to the reduction of monoterpene chemistry from the Master Chemical Mechanism (MCM) combined with the Peroxy Radical Autoxidation Mechanism (PRAM) mechanism. The original mechanism, consisting of 3 001 reactions and 1 227 species (including 738 condensable species), is reduced by 93% to 197 reactions and 110 species (including 23 condensable species), inducing an average error of only 3% in aerosol concentrations. Sensitivity tests showed that this reduced mechanism behaved similarly to the original mechanism in response to changes in environmental conditions such as temperature, relative humidity, and SOA mass loading. Moreover, if the error tolerance is increased to 20% — which can still be acceptable for 3-D air quality modeling — the mechanism can be further simplified to 40 reactions and 24 species (including 5 condensable species). Consequently, the GENOA-generated aerosol mechanism preserves the complexity of the detailed gas-phase chemical mechanisms on SOA formation while increasing computational efficiency, which makes it suitable for most environmental conditions encountered in the atmosphere
Development of a lung-liver in vitro coculture model for inhalation-like toxicity assessment
No full textInternational audienceAnimal models are considered prime study models for inhalation-like toxicity assessment. However, in light of animal experimentation reduction (3Rs), we developed and investigated an alternative in vitro method to study systemic-like responses to inhalation-like exposures. A coculture platform was established to emulate inter-organ crosstalks between a pulmonary barrier, which constitutes the route of entry of inhaled compounds, and the liver, which plays a major role in xenobiotic metabolism. Both compartments (Calu-3 insert and HepG2/C3A biochip) were jointly cultured in a dynamically-stimulated environment for 72 h. The present model was characterized using acetaminophen (APAP), a well-documented hepatotoxicant, to visibly assess the passage and circulation of a xenobiotic through the device. Based on viability and functionality parameters the coculture model showed that the bronchial barrier and the liver biochip can successfully be maintained viable and function in a dynamic coculture setting for 3 days. In a stress-induced environment, present results reported that the coculture model emulated active and functional in vitro crosstalk that seemingly was responsive to xenobiotic exposure doses. The hepatic and bronchial cellular responses to xenobiotic exposure were modified in the coculture setting as they displayed earlier and stronger detoxification processes, highlighting active and functional organ crosstalk between both compartments
Identification of safety critical scenarios of hydrogen refueling stations in a multifuel context
No full textInternational audienceThe MultHyFuel Project, funded by the Clean Hydrogen Partnership, aims to achieve the effective andsafe deployment of hydrogen as a carbon-neutral fuel, by developing a common strategy forimplementing Hydrogen Refueling Stations (HRS) in a multifuel context. The project hopes tocontribute to the harmonisation of existing regulations, codes and standards (RCS) by generatingpractical, theoretical and experimental data related to HRS.This paper presents how a set of safety critical scenarios have been identified from the initial preliminaryas well as detailed risk analysis of three different hydrogen refueling station configurations. To achievethis, a detailed examination of each potential hazardous phenomenon (DPh) or major accident event ator near the hydrogen dispenser was carried out. Particular attention is paid to the scenarios which couldaffect third parties external to the refueling station.The paper presents a methodology subdivided into the following steps: determination of the consequence level and likelihood of each hazardous phenomenon, the classification of major hazard scenarios for the 3 HRS configurations, specifically thosearising on the dispensing forecourt; proposal of example preventative, control and/or mitigation barriers that could potentiallyreduce the probability of occurrence and/ or consequences of safety critical scenarios, and hencereducing risks to a tolerable level or to as low as reasonably practicable
Safety challenges related to the use of hydrogen/natural gas blends in gas turbines
No full textInternational audienceIn a context of the decarbonization of the power sector, the gas turbine manufacturers are expected tohandle and burn hydrogen or hydrogen/natural gas mixtures. This evolution is conceptually simple inorder to displace CO2 emissions by H2O in the combustion exhaust but raises potential engineering andsafety related questions. Concerning the safety aspect, the flammability domain is wider and the laminarflame speed is higher for hydrogen than for natural gas. As a result, handling fuels with increasedhydrogen concentration should a priori lead to an increased the risk of flammable cloud formation withair and also increase the potential explosion violence.A central topic for the gas turbine manufacturer is the quantification of the hydrogen fuel content fromwhich the explosion risk increases significantly when compared with the use of natural gas.This work will be focused on a risk study of the fuel supply piping of a gas turbine in a scenario wheremixing between fuel and air would occur. The pipes are a few dozens of meters long and showsingularities: elbows, connections with other lines … They are operated at high temperature andatmospheric or high pressure.The paper will first highlight through CFD modelling the impact of increasing hydrogen content in thefuel on the explosion risk, based on a geometry representative of a realistic system. Second, thequantification of the explosion effects will be addressed. Some elements of the bibliography relative toflame propagation in pipes will be recalled and put in sight of the characteristics of the industrial case.Finally, a CFD model proposed recently for accounting for methane or hydrogen flames propagating inlong open steel tubes was used to assess a hydrogen fuel content from which the flame can stronglyaccelerate and generate significative pressure effects, for a flammable mixture initially at atmosphericconditions
Experimental Campaign of Massive CO2 Atmospheric Releases in an Urban Area
No full textInternational audienceOver recent decades, several campaigns have been carried out to collect data regarding the release and atmospheric dispersion of dense chemical products in an open field. All these experimental data are valuable information to challenge the predictions of numerical tools (Gaussian, integral-type, and CFD) and, if needed, to improve the code itself and the way we are using it. On the other hand, little attention has been paid to atmospheric dispersion releases with massive flow rates in a complex urban environment. To fill this gap, Ineris carried out an experimental campaign intended to study the atmospheric dispersion of massive CO2 releases on the CENZUB site (an action training center in an urban area located in Sissonne, France). Three CO2 releases were performed with mass flow rates of about 7 kg/s in three different configurations: one axial street release and two impacting releases (against a small and high-rise building). Several technologies of CO2 sensors were used to ensure better measurement accuracy. The main experimental campaign features and preliminary data analysis are presented. The results demonstrated the influence of the built environment on dispersion patterns
Fate and impact of iodinated contrast media in exposed aquatic organisms - a metallomic approach
No full textInternational audienceIodinated contrast media (ICM) used in X-ray imaging for diagnosis purpose are released into waste water and then encountered in natural water at usually several dozen of μg.L-1 and sometimes up to hundred μg.L-1. ICM are considered as emerging pollutants as the knowledge about their occurrence and impact on ecosystems and environment is extremely limited. Even so they are synthesized in order to be not toxic for human, aquatic organisms are continuously exposed and therefore their potential deleterious effect is questione