Vermiculite is a mineral that can be found virtually everywhere. It is contained in fertilizers, pesticides, potting mixes, and many construction applications like insulation, paints, and fireproofing materials. Vermiculite is an inexpensive mineral that is easily available, which is why it has been used for decades to help insulate homes and other buildings. When vermiculite is pure, the mineral can be very useful. But it has been discovered that vermiculite compounds are often tainted with asbestos. Over the last 10 years, there have been innumerable cases of asbestos found in vermiculite.
The reason for this is that the two minerals are often naturally found in deposits together, and when the vermiculite is mined, workers inadvertently disturb the naturally-occurring asbestos around it. This was the case in Libby, Montana, site of a W.R. Grace vermiculite mine. Unfortunately, miners were not the only ones exposed to the asbestos. Mining refuse around the town, as well as fibers carried home on clothes or in hair, exposed most of the townspeople to the dangerous substance.
With the discovery of so much vermiculite containing toxic asbestos, the mines are being tested more and more frequently, but there are still reports of asbestos fibers in the mineral. These tainted mixtures continue to be sold and the residents of many communities like Libby where the processing of vermiculite occurs have developed asbestos-related diseases like mesothelioma.