That TED talk was a huge disappointment for me. Early on, the speaker made erroneous claims, which for me, negated the legitimacy of the entire talk. Vermiculite is
not a toxic form of asbestos. It is not asbestos at all.
That mine was shut down around 1990, because it was known to be contaminated. Some of the contaminated vermiculite
may have been used as late as 1995 as insulation.
Concerns about Asbestos-contaminated Vermiculite Insulation
A mine near Libby, Montana, was the source of over 70 percent of all vermiculite sold in the United States from 1919 to 1990. There was also a deposit of asbestos at that mine, so the vermiculite from Libby was contaminated with asbestos. Vermiculite from Libby was used in the majority of vermiculite insulation in the United States and was often sold under the brand name Zonolite. If you have vermiculite insulation in your home, you should assume this material may be contaminated with asbestos and be aware of steps you can take to protect yourself and your family from exposure to asbestos.
It
should be noted that the EPA, while stating that homes from that era might be contaminated, does
not recommend that you remove it. Perhaps they feel that it is less of a danger
behind your walls than it would be if exposed for removal.
There was also a mine in Virginia shut down for the same reason. Since vermiculite and asbestos are often found together, it is now required that all vermiculite mines be inspected periodically for contamination.
It is not a pretty picture, but it is not as the speaker described it.
TED gets a thumb's down from me on this one.