Agency for Toxic Substances and Disease Registry (ATSDR) Vermiculite Consumer Products
Background
Vermiculite is a naturally occurring mineral compound composed of shiny flakes, resembling mica. When heated to a high temperature, flakes of vermiculite expand as much as 8-30 times their original size.
Historically, much of the world's supply of vermiculite came from a mine near Libby, Montana.
The Libby mine also had a natural deposit of asbestos, and the vermiculite from Libby is contaminated with asbestos. The information below describes possible health hazards posed by products made from asbestos-contaminated vermiculite.
Courtesy of The ATSDR
Olite attic insulation in Washington - An asbestos vermiculite problem