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鉴定石棉的方法，该方法使用偏振光显微镜，在对至少100毫克的灰化样品进行主要-次要元素分析之前。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术和经验，取决于在显微镜下检查的几微克材料的样品不均匀性引起的变化，或者需要极其昂贵且通常速度缓慢的设备来克服由显微镜工作者的不同技术引起的可变人为误差。主-次要元素分析可以用廉价、低维护、非专业设备如原子吸收分光光度计快速完成。一些样品的初步研究表明，这种组合系统很容易消除显微镜单独产生的最常见的误差来源，用于分析建筑材料中的石棉。许多单独的建筑材料都有矿物填充物，这些填充物来自基于当地资源的有限共生。因此，矿物学、主要、次要和微量元素应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，根据最合理的几个计算机模型来反向计算可能存在的矿物百分比，这些模型是根据特定共生组合的假设编写的，用于从分析中计算矿物。这将倾向于消除许多误报，特别是在含有低水平石棉的困难样品中。廉价、省时的方法提高了石棉矿物分析的可靠性，具有直接的商业应用。进行石棉分析的实体，如政府机构、工业卫生学家、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.