Comparison of the Efficiency of Polycarbonate and Mixed Cellulose Ester Filtersfor Use in the Filtration of Water Samples

摘要

The federal standard for the presence of asbestos in drinking water mandates theuse of transmission electron microscopy (TEM) as the only acceptable testing method. The July 17, 1992 Federal Register specifies that the analysis for asbestos shall be conducted by the EPA Protocol entitled 'Analytical Method for Determination of Asbestos Fibers in Water' (EPA-600/4-83) developed by Chatfield and Dillon (1), using polycarbonate (PC) membrane filters. A separate document (1993) providing guidance and clarification of the Chatfield method has been peer reviewed, which allows some slight changes to what was originally a research method, but still requires the use of PC filters. A draft of an alternative method using mixed cellulose ester (MCE) membrane filters was recently published in The Microscope (2). The experiment was designed to determine the quantitative differences between the two methods for all fiber lengths as well as for the regulated fibers > or = 10 micrometers in length.