Environmental exposure to Libby Asbestos and mesotheliomas.

BACKGROUND: Thirty-one cases of mesothelioma resulting from exposure to Libby Asbestos have been identified from Libby, Montana. Eleven cases not previously reported are the subject of this report. METHODS: These cases are in non-occupationally exposed people, appearing to have resulted from exposure to contamination of the community, the surrounding forested area, and areas in proximity to the Kootenai river and railroad tracks used to haul vermiculite. RESULTS: These exposures are considered to be of a low degree of magnitude, but are similar to those in Western Australia's crocidolite mine at Wittenoom Gorge. An epidemic of mesothelioma can likely be expected from this type of asbestos contamination over the next 20 plus years.