Industrywide Exposure Assessment Study of Workers Exposed to Graphene and other Two-Dimensional Nanomaterials

在过去的十年中，超薄二维（2-D）纳米材料的研究进展和创新取得了惊人的进展。这些二维纳米材料包括工业规模的材料，如石墨烯，以及新兴材料，如六方氮化硼、硅烯、二硫化钼，以及许多其他材料，因为它们展示了大量独特的物理性质而引起了相当大的兴趣。二维纳米材料在电子、能源存储、水修复、油漆和涂料、传感器、照明、复合材料和生物医学等领域具有巨大的应用潜力。随着二维纳米材料的应用不断增加，并进一步扩展到工业应用中，这些材料在整个生命周期中的工作场所和环境暴露的可能性也将不断增加。迄今为止，在已发表的文献中发现的评估这些材料毒性的研究相对较少，关于工作场所接触和接触评估方法发展的数据更少。在2020财年，NIOSH确定了另外21家可能处理石墨烯或其他二维纳米材料的公司。这个项目的公司数据库现在由88家美国二维纳米材料公司组成。NIOSH已经通过电子邮件和电话联系了另外31家公司，讨论参与这项研究。五家公司已经同意参与这项研究。五家公司中的三家公司在实施COVID-19旅行限制之前完成了工业卫生现场评估的预定日期。NIOSH一直与这些公司保持联系，一旦旅行限制取消，他们仍然有兴趣参与。另有四家公司表示有兴趣参与这项研究。在2020财年，NIOSH在一家二级制造商完成了一个工业卫生现场评估，招募了研究参与者并收集了空气样本，用于评估可吸入元素碳、可吸入元素碳和透射电子显微镜。NIOSH获得了4种具有商业意义的不同类型的石墨烯材料和不同的表面积，以确定气溶胶特性（粉尘和质量中值气动直径）。在各种石墨烯材料上进行气溶胶特性实验的实验设计和标准操作程序正在开发中，这些研究将于2021财年开始。

The past decade has witnessed an extraordinary increase in research progress and innovation on ultrathin two-dimensional (2-D) nanomaterials. These 2-D nanomaterials include industrial scale materials, such as graphene, as well as emerging materials such as hexagonal boron nitride, silicene, molybdenum disulfide, and many others that have generated considerable interest as they demonstrate a vast array of unique physical properties. Two-dimensional nanomaterials offer great potential in numerous applications such as in electronics, energy storage, water remediation, paints and coatings, sensors, lighting, composites, and biomedicine. As the utilization of 2-D nanomaterials continues to rise, with greater expansion into industrial applications, the potential for workplace and environmental exposures throughout the life cycle of these materials will successively increase as well. To date, there have been relatively few studies found in the published literature evaluating the toxicity of these materials, and even fewer data are available regarding workplace exposures and the development of exposure assessment methodologies. In FY20 NIOSH identified an additional 21 companies potentially handling graphene or other 2-D nanomaterials. The company database for this project now consists of 88 US based 2-D nanomaterial companies. NIOSH has contacted an additional 31 companies by email and a phone call to discuss participation in this study. Five companies have agreed to participate in the study. Three companies (of the five) had a scheduled date to complete the industrial hygiene site assessment prior to the COVID-19 travel restrictions being put in place. NIOSH has remained in contact with these companies and they are still interested in participating once travel restrictions are lifted. An additional four companies have expressed initial interest in participating in the study. In FY20, NIOSH completed one industrial hygiene site assessment at a secondary manufacturer, enrolled study participants and collected air samples for evaluation of inhalable elemental carbon, respirable elemental carbon, and transmission electron microscopy. NIOSH has obtained 4 different types of graphene materials of commercial relevance and varying surface areas to determine aerosol characteristics (dustiness and mass median aerodynamic diameter). The experimental design and standard operating procedures to conduct the aerosol characterization experiments on the various graphene materials is being developed and those studies will begin in FY21.