Abstract
Abstract A provisional method has been developed for the quantitation of biogenic silica fibers. Particles were sampled onto track-etched filters prepared by the direct-clearing method for transmission electron microscopy analysis. Fibers were identified by their length/width ratio, X-ray spectrum, and electron diffraction pattern. Biogenic silica fibers were found to contain mainly silicon and no aluminum, and to have an amorphous crystal structure. Approximately 100 samples from rice farming operations were analyzed. Cyclones were used to exclude large, nonrespirable particles when sampling near farming operations. The optimum fiber loading was found to be 100 to 1000 fibers/mm2. To prevent overloading, in most cases the sampled volume was held to 30 L using 25-mm filters, giving a limit of detection of 0.1 fibers/cc. Higher volumes were practical when sampling away from farming operations, giving limits of detection ranging from 0.02 to 0.004 fibers/cc. For a given microscopist, the coefficient of vari...
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
