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Erionite as an occupational and environmental hazard in the Western U.S.

Harpe M
AIHce 2015: American Industrial Hygiene Conference and Exposition, May 30 - June 4, 2015, Salt Lake City, Utah. Falls Church, VA: American Industrial Hygiene Association, 2015 May; :63
Objective: The objective of this study is to evaluate the presence and hazard potential of the fibrous zeolite mineral erionite in the western states. Methods: Samples containing erionite have been collected from several areas. Cliffs in north-west Oregon were sampled at various horizons and examined under an optical microscope in the field. Approximately 10 kg of rock with the greatest concentration of erionite fibers (about 80%) were collected and transferred to RTI International to be made available as a research material. Cliffs in the Custer National Forest of South Dakota and Montana were also sampled. The Arikaree Formation (Palaeogene) contained up to 20% erionite. Finally, "woolly" erionite was collected near Austin, Nevada. These materials have been examined by phase-contrast and polarized light microscopy, scanning and transmission electron microscopy (with energy-dispersive spectroscopy) and x-ray diffraction. Preliminary toxicological experiments have been carried out to provide data on which to base a more comprehensive study. Results: Rome, OR erionite is now available in 10 gm vials from RTI International. Erionite is seen to be a highly diverse mineral, with a range of morphologies, and a considerable range of cation chemistry between sources, and also between individual particles from a single source. A cation content methodology for identifying erionite could not be supported and a method based on polarized-light microscopy and x-ray diffraction appears necessary. Finally, preliminary studies point to possible differences in toxicity between materials from different locations. Conclusions: Exposures to erionite have already been documented in aggregate mineral extraction and road construction and maintenance. However, the hazard posed by erionite may vary from location to location.
Minerals; Hazards; Exposure-levels; Risk-factors; Fibrous-bodies; Sampling; Microscopy; Toxicology; Morphology; Chemical-composition; Chemical-reactions; Particulates
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Agriculture, Forestry and Fishing
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AIHce 2015: American Industrial Hygiene Conference and Exposition, May 30 - June 4, 2015, Salt Lake City, Utah
Page last reviewed: May 11, 2023
Content source: National Institute for Occupational Safety and Health Education and Information Division