How dangerous is vermiculite plus asbestos insulation?

Vermiculite insulation containing asbestos is about as dangerous as any other type of insulation that contains asbestos. If it becomes airborne and people breath in the fibers, their risk of contracting an asbestos related disease increases. The amount of increased risk depends on how much asbestos is in the insulation, how much becomes airborne, how long the people are exposed to the airborne fibers, and whether they smoke tobacco products.