A newspaper article has been making the rounds about the sad situation in Libby, Montana, a touchstone of anti-asbestos activism. Here are a few reasons why it is irrelevant to the situation in California, where lawmakers are trying to undeclare serpentinite as the state rock (see the previous post).
- Libby was not the site of an asbestos mine, but a vermiculite mine. Huge amounts of finely ground mining waste were what endangered the population.
- The harmful mineral at Libby was a fibrous variety of tremolite, which has no industrial use as asbestos. It was a contaminant. The only reason it can be called "asbestos" is because its fine, needlelike particles fall under the EPA regulations for asbestos.
- The rock in Libby was not serpentinite.
- The most common mineral used for asbestos that occurs in serpentinite is chrysotile. Careful medical studies have not shown any substantial harm from chrysotile dust.
- Asbestos regulations do not distinguish between chrysotile and genuinely harmful minerals such as crocidolite and tremolite.