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International audience; Research on graphene-related two-dimensional (2D) materials (GR2Ms) in recent years is strongly moving from academia to industrial sectors with many new developed products and devices on the market. Characterization and quality control of the GR2Ms and their properties are critical for growing industrial translation, which requires the development of appropriate and reliable analytical methods. These challenges are recognized by International Organization for Standardization (ISO 229) and International Electrotechnical Commission (IEC 113) committees to facilitate the development of these methods and standards which are currently in progress. Toward these efforts, the aim of this study was to perform an international interlaboratory comparison (ILC), conducted under Versailles Project on Advanced Materials and Standards (VAMAS) Technical Working Area (TWA) 41 “Graphene and Related 2D Materials” to evaluate the performance (reproducibility and confidence) of the thermogravimetric analysis (TGA) method as a potential new method for chemical characterization of GR2Ms. Three different types of representative and industrially manufactured GR2Ms samples, namely, pristine few-layer graphene (FLG), graphene oxide (GO), and reduced graphene oxide (rGO), were used and supplied to ILC participants to complete the study. The TGA method performance was evaluated by a series of measurements of selected parameters of the chemical and physical properties of these GR2Ms including the number of mass loss steps, thermal stability, temperature of maximum mass change rate (Tp) for each decomposition step, and the mass contents (%) of moisture, oxygen groups, carbon, and impurities (organic and non-combustible residue). TGA measurements determining these parameters were performed using the provided optimized TGA protocol on the same GR2Ms by 12 participants across academia, industry stakeholders, and national metrology institutes. This paper presents these results with corresponding statistical analysis showing low standard deviation and statistical conformity across all participants that confirm that the TGA method can be satisfactorily used for characterization of these parameters and the chemical characterization and quality control of GR2Ms. The common measurement uncertainty for each parameter, key contribution factors were identified with explanations and recommendations for their elimination and improvements toward their implementation for the development of the ISO/IEC standard for chemical characterization of GR2Ms.

The fate of sunscreen residues released during bathing activities around recreational areas is an emerging concern regarding the potential ecotoxicity of some of their ingredients, including nanoparticulate TiO

Investigating the transport of engineered nanoparticles through representative soils is an important issue in assessing their mobility and fate in the environment. In this study, successive injections of gold nanoparticles (AuNPs) were performed in a quartz sand column with an eluent composed of 10-2 M NaCl at a pH of 7.5. After this series of injections, remobilization of the AuNPs was examined by raising the eluent pH to 10. 197Au and the conservative ionic tracer 79Br were monitored simultaneously by online inductively coupled plasma mass spectrometry (ICP-MS), and the particulate nature of gold eluting from the column was confirmed by setting the ICP-MS in the "single particle" mode. The extent of AuNP attachment was greater than predicted by DLVO theory considering quartz as the sole collector, decreased with the number of injections and with particle size. In contrast with the repulsive interaction energy between the particles and the quartz surface, kaolinite, a secondary mineral of the sand, provided favorable conditions for particle attachment. The superimposed signals of 197Au and 27Al in the column effluent after pH increase suggest that gold nanoparticles were essentially remobilized as heteroaggregates with the kaolinite colloids they were attached to when favorable conditions for clay detachment from the sand grains were encountered.

International audience; The implementation in many products of manufactured nanoparticles is growing fast and raises new questions. For this purpose, the CEA - NanoSafety Platform is developing various research topics for health and safety, environment and nanoparticles exposure in professional activities. The containment optimisation for the exposition lowering, then the exposure assessment to nanoparticles is a strategy for safety improvement at workplace and workspace. The lowering step consists in an optimisation of dynamic and static containment at workplace and/or workspace. Generally, the exposure risk due to the presence of nanoparticles substances does not allow modifying the parameters of containment at workplace and/or workspace. Therefore, gaseous or nanoparticulate tracers are used to evaluate performances of containment. Using a tracer allows to modify safely the parameters of the dynamic containment (ventilation, flow, speed) and to study several configurations of static containment. Moreover, a tracer allows simulating accidental or incidental situation. As a result, a safety procedure can be written more easily in order to manage this type of situation. The step of measurement and characterization of aerosols can therefore be used to assess the exposition at workplace and workspace. The case of study, aim of this paper, concerns the potential emission of Lead nanoparticles at the exhaust of a furnace in an epitaxy laboratory. The use of Helium tracer to evaluate the performance of containment is firstly studied. Secondly, the exposure assessment is characterised in accordance with the French guide "recommendations for characterizing potential emissions and exposure to aerosols released from nanomaterials in workplace operations". Thirdly the aerosols are sampled, on several places, using collection membranes to try to detect traces of Lead in air

The treatment of waste containing nanoparticles (NP) will become a matter of first importance being given the increasing production and use of engineered NP. At present no specific end of life treatment is planned for such waste and most of the time it follows the path of conventional waste in incineration plants. The study of the behavior of NP at high temperature may help to define dedicated procedures and eventually lead to new regulations. This work deals with the set up of an incineration mounting at a laboratory scale. This assembly tested on NP samples shows significant results and interesting trends.

The implementation in many products of manufactured nanoparticles is in strong growth and raises new questions. For this purpose, the CEA – NanoSafety Platform is developing various research topics for health and safety, environment and nanoparticles exposure in professional activities. The working group Nano-CERT/MTD, driven by INERIS, federates actors of the sector: experts, research organizations, industrial users and manufacturers of collective protection. The main activity of this group is to establish specific guidelines or a voluntary certification of collective protection, at a national scale, but with the possibility of a further extension at an European level. The group aims to establish an experimental protocol of certification to characterize collective protections for workers faced with nanomaterials potential exposure. The NanoSafety Platform provides in this presentation a method of collective protection characterization based on the developments in nanoparticles metrology and on the study of existing standards and practices in related areas (chemicals, dust, microbiological and nuclear). This study presents the results obtained during the experimental characterization of a potential nanoparticles transfer in a prototype laboratory fume hood by the use of a particulate tracer of sodium-fluorescein. The efficiency of the equipment and more specifically the efficiency of dynamical air barrier is evaluated, with the experimental results, by calculating the backward diffusion coefficient.