I'll do a little cut and paste:
Minute quantities of asbestos were found in 4 of the existing vermiculite mines in North America. A subsequent random sampling of commercial vermiculite products found *trace* amounts of asbestos in approximately 15% of the products sampled.
The things to keep in mind: The amount of asbestos was so tiny that it was still considered perfectly safe and legal to sell. There is currently no reason to believe that even if you do happen to be using the small percentage of vermiculite with the nigh undetectable levels of asbestos that there's any vector for introducing it into your body in a dangerous manner. There's absolutely zero reason to assume that vermiculite produced outside of North America has even a possibilityof containing Asbestos.
I went out and bout a 28lb sack from the feed store just in case the public stupidity gets out of hand, though.