Libby Amphibole Asbestos – Not Just a Libby Risk

Occupational vs. Environmental Exposure

Many communities with vermiculite processing plants had exposure similar to Libby. The EPA estimates that Zonolite insulation is present in up to 30 million homes across the nation. Libby Amphibole asbestos was transported across the nation to nearly 300 processing facilities. Vermiculite products were used in many public places such as parks, schools, sports fields, tracks, lawns and gardens.

Occupational Exposure

  • Cleaning locations insulated with vermiculite
  • Working at power plants, oil refineries, or steel mills
  • Construction and maintenance occupations
  • Furnace workers and Boilermakers
  • Automotive repair
  • The World Trade Centers were insulated with a spray on insulation product called “Monokote” that was contaminated with Libby Amphibole asbestos

Environmental Exposure

  • Frequenting areas of disintegrating building materials
  • Living in New York City during WTC destruction
  • Children playing in piles of vermiculite
  • Living or playing near the rail road on transportation routes
  • Living in a community with a former processing plant
  • Living in a home with vermiculite insulation
  • Landscaping in soil known to contain vermiculite

At peak output, the WR Grace vermiculite mine located in Libby was producing 80% of the world’s vermiculite. Vermiculite contaminated with Libby Amphibole asbestos was shipped to nearly 300 processing plants around the country. Upon delivery, the ore was exfoliated. Exfoliation is a process in which vermiculite ore is heated at high temperatures to expand or “pop” it.

These facilities are of particular concern because exfoliation released countless tons of asbestos-laden dust into the surrounding communities, at levels much greater than other processing methods. Members of these communities may have been exposed to asbestos-contaminated vermiculite ore through multiple pathways during operation, and residual fiber contamination continues to present a potential for hazardous exposure. The Agency for Toxic Substance and Disease Registry (ATSDR) is currently evaluating 28 of these processing sites.