SBIR Phase I: Paragenetic Chemical Limits on Asbestiform Material

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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.