GENERATION OF FIBROUS AEROSOLS IN NARROW SIZE RANGES

产生窄尺寸范围的纤维气溶胶

• 批准号: 3069055
• 负责人: CHING-PING FANG
• 金额: $ 5.38万
• 依托单位: NEW YORK UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-08-01 至 1996-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3069055
• 关键词: aerosols; air filtration; air sampling /monitoring; asbestos; computer program /software; environmental air flow; glass; molecular size

This SERCA proposal is the first stage of a program focussed on the relationships between fiber size and toxicity for asbestos and other durable mineral fibers. So far, the difficulties of interpreting results from experimental animal and in vitro studies of responses to fiber exposures have been due, in part, to the wide spread ranges of diameter and length of the administered fibers. The first objective of this study is to develop techniques for generating relatively monodisperse fibrous aerosols for laboratory use. Fibrous aerosols, with diameter in a range of 0.1 to 3.0 microm and length in a range of 2.5 to 20 microm, will be generated. A fluidized bed fibrous generator will generate fibrous aerosols with number concentrations of 10(2)-10(3)/ml at an output flowrate of 10 lpm. The polydisperse fibrous aerosols will then be classified by an inertial impactor-virtial impactor-membrane filter system. We expect that the geometric standard deviations for both fiber diameter and length of a variety of specific fractions will be within 1.50. The diameter ranges of interest for subsequent biological effects testing will be 0.15, 0.3-0.5 and 2.0-3.0 microm, and the selected length ranges will be <2.5, 2.5-5.0, 5.0-10,0 and >20.0 microm. The collected fibers could be used directly in vitro, in vivo instillation, or in vivo implantation studies, or could be resuspended (with some losses) for inhalation studies. Alternatively, the aerosols passing a given length cut could be fed directly into inhalation exposure chambers for studies of differential toxicity, e.g., the differences n response from cell culture or animal population to another could be attributed to the additional presence of a longer length fraction. Such studies, made feasible by may research in the next three years, will be performed at this Institute in collaboration with colleagues having appropriate expertise in inhalation toxicology, molecular biology, and pulmonary pathology. The second current objective is to use numerical computation to explore the aerodynamic properties and filtration characteristics of fibrous particles. The theoretical results will be compared with the plentiful data from the experimental part of this project. The increased understanding of the fiber deposition behavior due to the elongated geometry will help to establish improved predictive models for lung deposition of fibers, as well as a basis for optimizing the performance of the generation system.

该SERCA提议是针对该计划的第一阶段 纤维大小和石棉毒性之间的关系 耐用的矿物纤维。 到目前为止，解释结果的困难 从实验动物和对纤维反应的体外研究 暴露是由于直径范围较大的范围 和管理纤维的长度。 这项研究的第一个目标 是开发生成相对单分散纤维的技术 用于实验室使用的气溶胶。 纤维气溶胶，直径为范围 0.1至3.0 microm的长度为2.5至20 microm的长度，将为 生成。 流化的床纤维发电机将产生纤维 数量浓度为10（2）-10（3）/ml的气溶胶在输出处 流量为10 lpm。 然后，多分散的纤维气溶胶将是 由惯性撞击器撞击器膜过滤器分类 系统。 我们期望两种光纤的几何标准偏差 直径和各种特定分数的长度将在 1.50。 随后的生物学作用的感兴趣的直径范围 测试将为0.15、0.3-0.5和2.0-3.0 microm，并且所选长度 范围为<2.5、2.5-5.0、5.0-10,0和> 20.0 microm。 收集的 纤维可以直接在体外，体内滴注或体内使用 植入研究，或可以重悬于（有些损失） 吸入研究。 或者，气雾剂通过给定的长度 切割可以直接送入吸入暴露室进行研究 差异毒性，例如，差异的差异n反应 培养或动物种群可以归因于 长度分数的额外存在。 这样的研究 在未来三年的5月研究中可行，将在 该研究所与合适的同事合作 吸入毒理学，分子生物学和肺部方面的专业知识 病理。 第二个目的是使用数值计算 探索空气动力学特性和过滤特性 纤维颗粒。 理论结果将与 该项目实验部分的大量数据。 增加 理解由于拉长而引起的纤维沉积行为 几何形状将有助于建立改进的肺预测模型 纤维的沉积以及优化性能的基础 生成系统。