SBIR Phase I: Paragenetic Chemical Limits on Asbestiform Material

这个小企业创新研究第一阶段项目是开发一种方法来识别石棉，使用偏振光显微镜，然后对至少100毫克灰化样品进行主-次元素分析。目前鉴定石棉的方法的可靠性取决于显微镜工作者的原始技能和经验，取决于显微镜下检查的几微克材料的样品异质性所引起的变化，或取决于需要极其昂贵且通常缓慢的设备来克服显微镜工作者的可变技能所引起的可变人为错误。 主-次元素分析可以用廉价、低维护、非专业设备如原子吸收光谱仪快速完成。 一个试点研究与几个样本表明，这种组合系统很容易消除最常见的错误来源，单独显微镜在分析建筑材料的石棉。 许多建筑材料都含有矿物填料，这些矿物填料来自于基于当地来源的有限共生。 因此，矿物学、主要、次要和微量元素应能表明岩石来源是否可能含有石棉矿物。 该项目旨在将元素分析与显微镜相结合，以基于最合理的几种计算机模型来反算可能存在的矿物百分比，这些计算机模型被编写用于根据特定共生套组的假设从分析中计算矿物。 这将有助于消除许多假阳性，特别是在含有低水平石棉的困难样品中。 提高石棉矿物分析可靠性的廉价、省时的方法具有直接的商业应用价值。从事石棉分析的实体，如政府机构、工业化学家、咨询实验室和教育机构是一个潜在的市场。

This Small Business Innovation Research Phase I project is to develop an approach for identification of asbestos which uses polarized light microscopy preceded by a major-minor elemental analysis of at least 100 mg of ashed sample. The reliability of current methods of identification of asbestos depend upon the raw skill and experience of microscopists, the variations caused by sample heterogeneity based upon a few micrograms of materials examined under a microscope, or the need for extremely expensive and often slow equipment to overcome the variable human error that arises from variable skills of microscopists. The major-minor elemental analyses can be done rapidly with inexpensive, low maintenance, nonspecialized equipment such as atomic absorption spectrophotometers. A pilot study with a few samples has shown that this combined system easily eliminates the most common sources of error that microscopy alone produces in analyses of building materials for asbestos. Many individual building materials have mineral fillers that come from a restricted paragenesis based upon local sources. Thus mineralogy, major, minor and trace elements should be indicative of a rock source that is or is not likely to contain asbestos minerals. This project seeks to extend the elemental analysis in conjunction with the microscopy to back-calculate likely mineral percentages present based upon the most reasonable of several computer models that are written to calculate minerals from analyses based on assumptions of particular paragenetic suites. This would tend to eliminate many false positives, especially in the difficult samples that contain asbestos at low levels. Inexpensive, time-saving procedures which improve the reliability of asbestiform mineral analysis have immediate commercial application. Entities performing asbestos analysis such as government agencies, industrial hygienists, consulting laboratories, and educational institutions are a potential market.