Abstract

Few-Layers Graphene (FLG) are able to improve the performance of materials, due to their chemical-physical properties. Engineered amorphous silica nanoparticles (SiO₂NPs) are among the most widespread nanomaterials (NMs) in the world. Such nanomaterials are two case studies of the research project ‘NanoKey’ that integrated the exposure assessment through personal measurements and sampling in the workplace, as described in the present work (part I), with the biomonitoring of exposed workers (reported in part II). Measurement campaigns were conducted according to OECD and WHO harmonized approach in two production sites. The set of instruments included real-time devices for high-resolution measurements at the nanoscale and time-integrated samplers for the off-line gravimetric analysis and chemical and morphological (SEM-EDS) characterization of exposure in order to identify the contribution of production compared to the background. Values of particle number concentration (PNC) and lung deposited surface area (LDSA) within the FLG production resulted higher than the background far field (FF), even if they are always similar to the near field (NF) ones: the average diameter (D_avg) during the production was higher than the NF background but always lower than the FF values. SEM-EDS analysis highlighted the presence of structures comparable to those produced. During the SiO₂NPs production, the PBZ values showed PNC and LDSA levels higher than the background, with a decrease in the D_avg probably due to NPs emission. SEM-EDS confirms the presence of rare silica nanoparticles. Since the exposure to airborne NMs cannot be excluded in both production sites, a prevention-through-design approach to mitigate the potential risk for workers has been recommended.

摘要

很少层石墨烯（FLG）由于其化学物理特性而能够改善材料的性能。工程无定形二氧化硅纳米粒子（SiO ₂NPs）是世界上最广泛的纳米材料（NMs）之一。此类纳米材料是研究项目“ NanoKey”的两个案例研究，该研究将个人评估和工作场所采样（如本工作（第一部分）中所述）与暴露工人的生物监控（在第二部分中报告）相结合，将暴露评估结合在一起。 。根据经合组织和世卫组织的统一方法，在两个生产地点开展了测量运动。这套仪器包括用于纳米级高分辨率测量的实时设备和用于离线重量分析以及曝光化学和形态学（SEM-EDS）表征的时间集成采样器，以便确定所比较的生产贡献到背景。生产期间的_平均值）高于NF背景，但始终低于FF值。SEM-EDS分析突出显示了与所产生结构可比的结构。在SiO ₂ NPs的生产过程中，PBZ值显示PNC和LDSA的水平高于背景水平，D _avg的降低可能是由于NPs的排放。SEM-EDS证实了稀有二氧化硅纳米粒子的存在。由于不能在两个生产地点都排除空气中的NMs暴露，因此建议采用通过设计预防的方法来减轻工人的潜在风险。