Mining Project: Developing a Roadmap and Reference Materials for Minerals and Materials Research
To characterize and make available for research, two sets of reference fibrous mineral materials—(1) anthophyllite asbestos and (2) actinolite-tremolite asbestos—using previously collected bulk naturally occurring elongate minerals, and to develop a roadmap for future mineral and material research specific to the mining industry.
According to a U.S. Geological Survey mineral commodity summary, in 2015, 1.32 billion metric tons of crushed stone valued at more than $13.8 billion was produced by 1,430 companies operating 3,700 quarries, 82 underground mines, and 187 sales/distribution yards in 50 states. During the extraction, processing, and use of these aggregates, asbestos and other elongate mineral particles (EMPs) that are natural constituents of rock can be aerosolized. EMPs have been identified in many mines, and the 1996 National Occupational Health Survey of Mining (NOHSM) recorded detectable asbestos in settled dust collected from mines involved in the extraction of 21 different non-asbestos commodities. Further, in samples collected during 2000-2003, the Mine Safety and Health Administration (MSHA) found that a significant percentage of personal samples had mineral fiber concentrations in excess of the concentration of 0.1 fibers/cc regulated by the Occupational Safety and Health Administration (OSHA). Finally, current health concerns also include exposures to particles of other elongate minerals (erionite, talc, attapulgite, etc.) as well as to non-asbestiform amphibole and serpentine mineral cleavage fragments.
To help address this problem, a knowledge gap must be filled, as identified in the NIOSH Current Intelligence Bulletin, “Asbestos Fibers and Other Elongated Mineral Particles: State of the Science and Roadmap for Research.” This bulletin calls for a national repository of samples of asbestos and related minerals that are well-characterized, research-grade materials to be made available to the research community so they can be used for testing and standardization.
To begin the process of creating such a repository, this pilot project had three aims:
- to further characterize and confirm the suitability of two reference fibrous mineral samples (anthophyllite asbestos and actinolite-tremolite asbestos) already collected through prior projects;
- to publish the characterization data, and
- to prepare aliquots of the material and make them available for public use.
Outputs from this project research include publication of research findings in the peer-reviewed literature, the addition of minerals to a repository of well-characterized reference minerals available as a public resource and a mining specific minerals and materials research white paper. It is expected that these outputs will be used to further knowledge associated with health effects resulting from exposure to fibrous airborne particles. This project fully characterized the reference materials and they are now available to the public.