Vermiculite and Libby, Montana

The Libby mine operated for decades until it closed in 1990. Miners and mill workers breathed dust from contaminated ore, and dust spread through the town from processing, transportation and waste materials used in yards and playgrounds. Residents who never worked at the mine developed asbestos-related diseases. The EPA declared a public health emergency in Libby in 2009, the first such declaration under its Superfund authority. Cleanup work took place over many years, and a local clinic has provided screening and care for people exposed in the area. The story of Libby drew national attention to the dangers of contaminated minerals.

Ore from Libby was shipped to processing plants around the United States, where it was expanded and sold. One widely known product was Zonolite attic insulation, which was poured into many homes. Vermiculite also appeared in garden products, some fireproofing and other materials. Workers at processing plants and people living near them could be exposed. Homeowners and contractors who handled loose attic insulation might have disturbed contaminated material. Not all vermiculite came from Libby, but much of the U.S. supply did for many years. Former processing plant locations have been studied by federal health agencies. Some have been cleaned up.

Vermiculite attic insulation looks like small, lightweight pebbles that are gray-brown or silver-gold. The EPA advises homeowners to assume it may contain asbestos and avoid disturbing it. Do not store items in an attic with this insulation or let children play there. If renovation is planned, hire a trained professional to handle it. Keep in mind that testing loose vermiculite can be unreliable, so professional guidance matters. A trust was established to address claims related to Zonolite attic insulation, and it has had its own procedures for homeowners. Keep any paperwork about your home's insulation with your property records.

1. 1

   Leave any vermiculite attic insulation undisturbed until a professional has assessed it.

2. 2

   Note whether you lived or worked in Libby or near a vermiculite processing plant.

3. 3

   Record any attic work you did involving loose, pebble-like insulation.

4. 4

   Ask about screening programs if you have a history of Libby-related exposure.