|Feds Warn That Vermiculite Insulation
Poses Danger From Asbestos
|In a recent memo to the
National Institute of Occupational Safety and Health, assistant U.S.
surgeon general, Dr. Hugh Sloan of the U.S. Public Health Service, has
warned that Asbestos-contaminated vermiculite insulation in millions of
homes across the country poses a "substantial health risk'' to
anyone who works in the houses' attics. "Internal company
documentation and recent testing of residential insulation material
reveals that even minimal handling by workers or residents poses a
substantial health risk,'' says Sloan. He goes on to say that
while recent studies show that even casual handling of the insulation can
expose workers or homeowners to 150 times the asbestos level considered
safe under federal regulations, the risk to homeowners would be small if
they leave the insulation alone. "My sense is that homeowners
themselves, if the insulation remains undisturbed, shouldn't have any
According to Aubrey K. Miller, an official
in the health service's Denver region, The Public Health Service has asked
the National Institute of Occupational Safety and Health to "look
into the current worker exposures that may be dealing with these products
and issue an alert if need be."
|What Is Vermiculite
|It is an insulation product
that contains a mineral called vermiculite that comes from mines in Libby,
Montana and other mines across the United States and other countries.
For more than 60 years, W.R. Grace & Co. dug vermiculite ore out of
the Zonolite Mountain in Libby. Vermiculite is a volcanic mineral compound
that expands when wet. It is used in agricultural, construction,
horticultural and industrial applications, including pesticides,
insulation, potting mixes, brake pads, sound deadening materials, fire
protection, paints, sealants, insulating concrete and nuclear waste
Insulation made of vermiculite was sold
under the brand name Zonolite, and was sold as a product for attic
insulation and marketed until the mid 1980's. Vermiculite from
Grace's mine at Libby, Mont., was sold for use in garden products,
fireproofing, cement mixtures and more than a dozen other consumer
products. The bulk of the ore was heated until it expanded like popcorn.
Then marketed as Zonolite insulation, it was stuffed between rafters and
inside walls in millions of homes from coast to coast.
Nobody is sure how many homes contain Zonolite. Estimates range between
2.5 million and 16 million.
"It sold like mad,'' said Stephen
Sheeran, who was a salesman for Grace in Michigan and eventually a sales
manager for the company. "Millions of bags of that stuff from Libby
were sold as attic fill insulation,'' Sheeran said. "They couldn't
get it fast enough." Vermiculite (Zonolite)
products were widely marketed by various suppliers. Records indicate that an
estimated 80 % of the worlds' supply of vermiculite came from
Libby, Montana. Records further indicated that approximately 300,000
pounds of asbestos per day went through the primary ore-processing
|What Does Vermiculite
Insulation Look Like?
|Vermiculite insulation is
easily distinguished from the much more common types of loose fill
insulations - cellulose, fiberglass and rock wool. All of these common
insulation types are fibrous. In contrast vermiculite is in the form of
brownish-pink or brownish-silver accordion-shaped chips.
on the thumbnail image to view a photo of vermiculite
in a typical residential attic.
on the thumbnail image to view a photo of a
view of vermiculite.
| Should I Have It Removed
From My Home?
|Before taking that step,
homeowners should consider a number of factors. First, removing
asbestos-containing materials is typically very expensive. If a
significant amount of material is involved, it will probably cost
thousands of dollars. Secondly, if the insulation is not exposed to the home environment - for example,
it's sealed behind wallboards and floorboards or is isolated in the attic
which is vented outside - the best advice might be to leave it alone.
If you suspect you have vermiculite in your
home, the U.S. Environmental Protection Agency (EPA) recommends you do not
disturb it. You should consider contacting an asbestos specialist
for further advice.