Conduct of method development and feasibility studies to support inhalation studies of cellulose nanomaterials

该项目的目标是评估四种不同的纤维素纳米材料的物理性质（大小、结晶度和吸湿性）和吸入暴露的可行性，这些材料似乎在肺部具有生物持久性。这些研究包括确定在美国有超过11000块人造草坪，每年大约增加1200块。草皮中最受关注的成分是由回收的汽车轮胎制成的橡胶屑填充物。橡胶屑含有许多潜在的致癌和有毒物质，但人们在安装的场地上玩耍时暴露于这些有害成分的情况尚不清楚。从国家毒理学规划毒理学研究中获得的信息将为公共卫生机构提供信息，以便为接触和健康评估提供信息。由于橡胶屑材料的物理性质，对进行毒理学研究存在重大挑战。除了为今后开展国家毒理学控制项目毒性研究的可行性提供信息并提供各种途径的系统性暴露信息外，这些数据还将帮助其他研究人员设计毒性研究并解释结果数据。

The goal of this project is to evaluate physical properties (size, degree of crystallinity and hygroscopicity) and feasibility of inhalation exposure of four different cellulose nanomaterials, which appear to be bio-persistent in the lung. These studies include determination of Over 11,000 synthetic turf fields exist in the U.S., with approximately 1,200 being added annually. The component of turf that is of most concern is crumb rubber infill, made from recycled automotive tires. Crumb rubber contains numerous potential carcinogenic and toxic substances, yet the exposure of people playing on installed fields to these hazardous components is not well understood. Information gained from NTP toxicology studies will provide public health agencies with information to inform exposure and health assessments. There are significant challenges to the conduct of toxicology studies due to the physical nature of the crumb rubber material. In addition to informing feasibility of conduct of future NTP toxicity studies and provide information on systemic exposure by various routes, these data will aid other researchers design toxicity studies and interpret the resulting data. Keywords: toxicity, nanocrystalline cellulose, nanomaterials, inhalation, lung