Qualitative and Semiquantitative Assessment of Exposure to Engineered Nanomaterials within the French EpiNano Program: Inter- and Intramethod Reliability Study

The relatively recent development of industries working with nanomaterials has created challenges for exposure assessment. In this article, we propose a relatively simple approach to assessing nanomaterial exposures for the purposes of epidemiological studies of workers in these industries. This method consists of an onsite industrial hygiene visit of facilities carried out individually and a description of workstations where nano-objects and their agglomerates and aggregates (NOAA) are present using a standardized tool, the Onsite technical logbook. To assess its reliability, we implemented this approach for assessing exposure to NOAA in workplaces at seven workstations which synthesize and functionalize carbon nanotubes. The prediction of exposure to NOAA using this method exhibited substantial agreement with that of the reference method, the latter being based on an onsite group visit, an expert’s report and exposure measurements (Cohen kappa = 0.70, sensitivity = 0.88, specificity = 0.92). Intramethod comparison of results for exposure prediction showed moderate agreement between the three evaluators (two program team evaluators and one external evaluator) (weighted Fleiss kappa = 0.60, P = 0.003). Interevaluator reliability of the semiquantitative exposure characterization results was excellent between the two evaluators from the program team (Spearman rho = 0.93, P = 0.03) and fair when these two evaluators’ results were compared with the external evaluator’s results. The project was undertaken within the framework of the French epidemiological surveillance program EpiNano. This study allowed a first reliability assessment of the EpiNano method. However, to further validate this method a comparison with robust quantitative exposure measurement data is necessary

Proposition d’une méthode de repérage des postes de travail potentiellement exposant aux nano-objets, leurs agrégats ou agglomérats dans les entreprises mettant en oeuvre des nanomatériaux manufacturés

Purpose of the study. To develop an operational method for identifying workers potentially exposed to manufactured nano-objects and their aggregates and agglomerates (NOAA) and assessing their potential exposure in frame of epidemiological surveillance program EpiNano. Method. The method was developed by a multidisciplinary working group. It consists of a company visit guided by a standardized tool "Field technical logbook". This tool enables assessing a set of parameters necessary for identification and characterization of workstations concerned with NOAA exposure, namely a detailed description of tasks and processes, personal and collective protection equipment, NOAA characteristics before and after transformation and other exposure surrounding conditions. The method was tested in ten companies. After each visit, all information collected in the logbook was computerized via a friendly-using application. A pdf copy of data was sent to the company along with proceedings of the visit listing workstations classified as concerned with NOAA exposure, for verification and validation. Results. All proceedings were validated. Among 53 workstations. observed during all the visits, 30 (57 %) were classified as concerned with NOAA exposure, namely workstations dealing with NOAA synthesis, sampling, transfer and functionalization. In private companies, there were 60 % of workstations classified as concerned with NOAA exposure versus 54 % in public companies. Numerous parameters were likely to determine the exposure classification, particularly humidity and dustiness of the NOAA powders. The assessment of these parameters might be useful for all companies since it also serves in implementing exposure control banding. Conclusion. This simple and non-instrumental method (without aerosol sampling and measurements) was developed for epidemiologists but could be useful to all occupational health actors in the field of nanotechnology.Objectif : Proposer une méthode opérationnelle pour identifier les travailleurs potentiellement exposés aux nano-objets manufacturés, leurs agrégats et agglomérats (NOAA) et caractériser leur exposition potentielle dans le dispositif de surveillance épidémiologique EpiNano. Méthode : La méthode a été conçue par un groupe de travail pluridisciplinaire. Elle repose sur une visite d’entreprise, guidée par un outil intitulé carnet d’observation technique (COT). Il permet de relever, dans un ordre logique, des éléments nécessaires au repérage et à la caractérisation des postes exposants, notamment les procédés mis en œuvre, l’aéraulique des ateliers, les équipements de protection, les caractéristiques des NOAA à l’entrée et à la sortie du poste, les conditions de leur manipulation, de la tenue du poste et de sa maintenance. La méthode a été testée au sein de dix entreprises. À l’issue de chaque visite, un compte rendu de mission listant les postes potentiellement exposant aux NOAA était envoyé à l’entreprise visitée. La copie des informations informatisées du COT était jointe au compte rendu pour vérification et validation. Résultats : L’ensemble des comptes rendus des missions a été validé. Parmi les 53 postes observés, 30 (57 %) ont été classés potentiellement exposant, notamment les postes de synthèse, d’échantillonnage, de transfert et de fonctionnalisation des NOAA. La proportion de postes de travail potentiellement exposant aux NOAA était de 54 % dans les entreprises privées et de 60 % dans les entreprises publiques. De nombreux paramètres semblent déterminants dans le classement d’un poste de travail, notamment la pulvérulence et la teneur en humidité des NOAA. La connaissance de ces paramètres peut également servir dans l’application de l’approche de gestion graduée du risque, et par conséquent être utile à l’entreprise. Conclusion : Cette méthode simple et non instrumentale (sans prélèvement et sans mesure de l’aérosol) conçue pour des épidémiologistes pourrait servir à l’ensemble des acteurs en santé et prévention au travail impliqués dans la gestion des risques liés aux nanomatériaux

Proposition de méthode pour identifier et observer des postes de travail potentiellement exposants aux nanomatériaux

Cet article présente la méthode ayant été testée et optimisée dans le cadre du dispositif de surveillance épidémiologique des travailleurs potentiellement exposés aux nanomateriaux en France, EpiNano. Cette méthode intègre les préconisations de l'INRS, de l'INERIS et du CEA dans l'étude dite de situation préalable à une campagne de mesurage. Elle se matérialise par un outil pragmatique : le Carnet d'observation technique (COT). Il s'agit d'un outil de collecte d'informations, conçu pour des épidémiologistes, qui pourrait servir à l'ensemble des acteurs de la santé et prévention au travail impliqués dans la gestion des risques liés aux nanomatériaux

A standardized non-instrumental tool for characterizing workstations concerned with exposure to engineered nanomaterials

International audienceThe French national epidemiological surveillance program EpiNano aims at surveying mid- and long-term health effects possibly related with occupational exposure to either carbon nanotubes or titanium dioxide nanoparticles (TiO2). EpiNano is limited to workers potentially exposed to these nanomaterials including their aggregates and agglomerates. In order to identify those workers during the in-field industrial hygiene visits, a standardized non-instrumental method is necessary especially for epidemiologists and occupational physicians unfamiliar with nanoparticle and nanomaterial exposure metrology. A working group, Quintet ExpoNano, including national experts in nanomaterial metrology and occupational hygiene reviewed available methods, resources and their practice in order to develop a standardized tool for conducting company industrial hygiene visits and collecting necessary information. This tool, entitled "Onsite technical logbook", includes 3 parts: company, workplace, and workstation allowing a detailed description of each task, process and exposure surrounding conditions. This logbook is intended to be completed during the company industrial hygiene visit. Each visit is conducted jointly by an industrial hygienist and an epidemiologist of the program and lasts one or two days depending on the company size. When all collected information is computerized using friendly-using software, it is possible to classify workstations with respect to their potential direct and/or indirect exposure. Workers appointed to workstations classified as concerned with exposure are considered as eligible for EpiNano program and invited to participate. Since January 2014, the Onsite technical logbook has been used in ten company visits. The companies visited were mostly involved in research and development. A total of 53 workstations with potential exposure to nanomaterials were pre-selected and observed: 5 with TiO2, 16 with single-walled carbon nanotubes, 27 multiwalled carbon nanotubes. Among the tasks observed there were: nanomaterial characterisation analysis (8), weighing (7), synthesis (6), functionalization (5), and transfer (5). The manipulated quantities were usually very small. After analysis of the data gathered in logbooks, 30 workstations have been classified as concerned with exposure to carbon nanotubes or TiO2. Additional tool validity as well as inter-and intra-evaluator reproducibility studies are ongoing. The first results are promising

A standardized non-instrumental method for tracking workstations concerned with exposure to nano-objects and their aggregates and agglomerates in companies dealing with engineering nanomaterials

The French national epidemiological surveillance program EpiNano aims at surveying mid- and long-term health effects possibly related with occupational exposure to either carbon nanotubes (NTC) or titanium dioxide nanoparticles (TiO2). EpiNano is limited to workers potentially exposed to these nanomaterials (NM) including their aggregates and agglomerates. In order to identify those workers during the in-field industrial hygiene (IH) visits, a standardized non-instrumental method is necessary especially for epidemiologists and occupational physicians unfamiliar with ENM exposure metrology. A working group, Quintet ExpoNano, including national experts in NM metrology and occupational hygiene reviewed available methods, resources and their practice in order to develop a standardized tool for conducting company IH visits and collecting necessary information. This tool, entitled “Field technical logbook”, includes 3 parts: company activity, workplace, and workstation allowing a detailed description of each task, process and exposure surrounding conditions. This logbook is intended to be completed during the company IH visit. Each visit is conducted jointly by an occupational hygienist and an epidemiologist of the program and lasts one or two days depending on the company size. When all collected information is computerized in a friendly-using database it is easy to classify workstations with respect to their potential direct and/or indirect exposure. Workers appointed to workstations classified as concerned with exposure are considered as eligible for EpiNano program and invited to participate. Since January 2014, the Field technical logbook has been used in ten company visits. The companies visited were mostly involved in research and development. A total of 53 workstations with potential exposure were pre-selected and observed: 5 with TiO2, 16 with single-walled NTC, 27 multiwalled NTC. Among the tasks observed there were: ENM analysis (8), weighing (7), synthesis (6), functionalization (5), and transfer (5). The manipulated quantities were usually very small. After analysis of the data gathered in logbooks, 30 workstations have been classified as concerned with exposure to NTC or TiO2. Additional tool validity as well as inter-and intra-evaluator reproducibility studies are ongoing. These first results are promising