The federal government’s Agency for Toxic Substances and Disease Registry conducted a review of vermiculite from the now notorious Libby Montana mine. This review, which they called the National Asbestos Exposure Review, is available on the web here: http://www.atsdr.cdc.gov/asbestos/sites/national_map/
Vermiculite is a mineral which was used for many things, and most vermiculite does not pose a significant health hazard. The vermiculite from Libby had asbestos in it. It’s a tragic story how the asbestos almost destroyed that town – so many health problems. When the vermiculite was shipped out, the asbestos hazard went with it. The NAER investigated major places where this vermiculite was processed from the early 1920s through 1990.