Direct Domestic Exposures

From the early 1920s, the Zonolite Company began vermiculite ore mining operations in Libby. In late November 1999, the U.S. Environmental Protection Agency sent an Emergency Response Team to the Libby Asbestos site located in Montana.Vermiculite from the Libby mine, bought by W.R. Grace in 1963, was contaminated with a toxic and highly friable form of asbestos called tremolite-actinolite series asbestos, often called Libby amphibole asbestos (LA). LA has been observed in air (indoor and outdoor ambient), vermiculite insulation and bulk materials, indoor dust, soil, water, animal and fish tissue and various other media in Libby. Investigation and cleanup of the site is ongoing and cleanup at portions of the site is complete.

Some Libby vermiculite home attic insulation produced before 1990 and many other home and building materials produced before asbestos was banned for fireproofing in 1975 still contain asbestos.

• People who live in homes with these materials are at risk of exposure if the materials are loose, crumbling, and disturbed by household activities or renovations.
• In such cases, the asbestos materials should be removed or encapsulated by a trained and certified asbestos contractor.
• For information on where to find certified asbestos contractors in your state, homeowners should contact their local health department.

On the other hand, asbestos contained in intact solid material poses a negligible risk of exposure. Air levels of asbestos in a building with asbestos embedded in building materials and undisturbed average 0.0002 f/cc, nearly 3 orders of magnitude below OSHA's permissible exposure limit for occupational exposures.

There are many ways that people can also be exposed to asbestos through hobbies and recreational activities that entail contact with materials containing asbestos; some examples are such activities as home renovation, auto repair, and urban spelunking. In places where naturally occurring asbestos is close to the earth's surface, activities such as gardening and dirt biking can cause exposures if asbestos-bearing rock is disturbed.

• Content source: Agency for Toxic Substances and Disease Registry
• Content source: US Environmental Protection Agency