Zonolite

Zonolite was the brand name for a vermiculite-based attic insulation sold in millions of American homes from the 1940s through the 1980s. The vermiculite was mined in Libby, Montana, and was contaminated with tremolite and other amphibole asbestos fibers. Although marketed as a safe, fire-resistant insulation, Zonolite is now recognized as a major source of residential and occupational asbestos exposure.

Origin

The name Zonolite was coined in the 1920s by the Zonolite Company of Montana, derived from the "zoned" expansion the mineral undergoes when heated. W.R. Grace & Co. acquired the Zonolite Company and the Libby mine in 1963 and continued marketing the product until the mine closed in 1990.

Significance in Asbestos Context

For patients with mesothelioma or other asbestos diseases, Zonolite is one of the most important consumer products to investigate during exposure history because it brought amphibole asbestos directly into homes (into attics, walls, and around chimneys) where homeowners, renters, contractors, and children were exposed during installation, renovation, or routine attic access. The Libby vermiculite was contaminated with particularly toxic Libby amphibole (a mix of tremolite, winchite, and richterite), which has been linked to mesothelioma at relatively low exposure levels. W.R. Grace filed for bankruptcy in 2001 largely because of Zonolite liabilities, and a dedicated Zonolite Attic Insulation Trust was established to compensate property owners and exposure victims. If you, a parent, or a spouse ever worked in an attic containing loose, pebbly, gold-brown or grayish insulation, that exposure may be a compensable source in your claim.

Example Sentence

When the lawyer asked about home renovations, the patient recalled helping his father pull Zonolite out of the attic in the 1970s, an exposure that became a key part of his mesothelioma case.

Related Terms

Libby Amphibole, Vermiculite, W.R. Grace & Co., Tremolite Asbestos, Asbestos Trust Fund, Take-Home Exposure

Notes

• If you suspect Zonolite is in a home where you lived or worked, do not disturb it. Contact a licensed asbestos abatement contractor; sampling and removal should not be done yourself.
• Photograph any remaining insulation, save purchase records or home inspection reports, and document the years you lived in or worked on the property; these support both a personal injury claim and a Zonolite Attic Insulation Trust property claim.
• Ask family members for memories of attic work, blown-in insulation, or renovations in homes built or insulated between roughly 1940 and 1990. Zonolite exposures often happened decades before diagnosis and are easily forgotten.
• The W.R. Grace Asbestos Personal Injury Trust accepts claims for mesothelioma, lung cancer, asbestosis, and other asbestos diseases tied to Zonolite or other Grace products; your attorney can file alongside any tort claims.
• The EPA maintains guidance on Zonolite and Libby vermiculite identification; a contractor can confirm whether attic insulation is vermiculite versus fiberglass or cellulose.