If you are a gardener, you are familiar with the term “Vermiculite”, Health Canada recently concluded national testing of horticultural (gardening) vermiculite products. These tests revealed mostly non-detected amounts of asbestos, with a few samples showing trace amounts of asbestos fibres. Based on these low levels, Health Canada has determined that the use of horticultural vermiculite, when used as directed by consumers, poses no additional risk of cancer. The United States’ Environmental Protection Agency has conducted similar testing and come to the same conclusion – that horticultural vermiculite is considered safe and does not pose an elevated risk of cancer to the user.
Vermiculite is a silver-gold to gray-brown mineral that is flat and shiny in its natural state. When heated to around 1000 degrees C, it pops (or puffs up) which creates pockets of air. This expanded form, and the fact that vermiculite does not burn, made the material suitable for use as insulation. Vermiculite can be poured in between joists and more commonly in the attics of homes after construction. It may appear as small pieces of “pop-corn.” The federal government estimates that it is in as many as 35 million homes in North America, 300,000 of in Canada, have Vermiculite insulation.
If you happen live in a house that was built before the 1970s, there’s a good chance that asbestos was used in its construction. Even if your house was built since then, asbestos may still be found in some areas. In fact, only houses built within the last 10 years or so should be free of insulating asbestos, although it could very easily have been used in other forms.
This knowledge may instill fear in many homeowners, but, a little knowledge can reduce anxiety. Once the background and use of asbestos is known, the homeowner should be able to recognize potentially dangerous situations. After being informed about the ways in which asbestos must be safely handled, the homeowner can be assured that proper safeguards are being taken. With widely prevalent asbestos use in construction during the early part of the 1900’s, and in hundreds of products since then, it’s been the subject of much research. Much has been learned about it and the threats it can pose. Inhalation of asbestos is the only known cause of pleural mesothelioma, a rare cancer that affects the lining of the lungs.
Is all vermiculite a health concern?
Vermiculite itself has not been shown to be a health problem. However, some vermiculite insulation contained asbestos fibres, which can cause problems if inhaled. As long as this kind of vermiculite-based insulation remains undisturbed behind intact walls or in attic spaces and does not become airborne, it should not be a concern.
Of concern is Zonolite® Attic Insulation; this insulation was sold in Canada under the name of Zonolite® and was extracted from the Libby Mine in Montana, USA. This mine had a natural deposit of asbestos which resulted in the vermiculite being contaminated with asbestos.
Vermiculite produced by the Libby Mine has not been on the market in Canada for more than 10 years. Not all vermiculite sold in Canada before 1990 contains asbestos fibres. However, if you believe that your home may contain vermiculite insulation, it is possible that it may have been contaminated with asbestos.
The best way to minimize asbestos exposure from vermiculite is to NOT remove or disturb the insulation. Moving the vermiculite will cause fibres to become airborne. The following precautions will prevent releasing asbestos fibres into the air:
•Do not use the attic for storage.
•Nobody should go into the attic.
•If you plan to renovate, hire a professional who is trained and certified to handle asbestos.
•Never remove the insulation yourself.
•Seal all cracks and holes in the ceilings to prevent insulation from sifting through.
As a realtor in Kitchener-Waterloo, it is mandatory to disclose that Vermiculite exists in a home. Over the years it has been disclosed as “UFFI” on a property listing, which is completely different from Vermiculite. Your agent will advise you of its existence and suggest an air quality test, (if not already done by the owner, prior to listing).
Should you run from the possible purchase of a home with Vermiculite?….NO! A precautionary measure for peace of mind is to have an air quality test done. This will determine if asbestos is airborne in the home. Your real estate agent will guide you through this process.