If you own a home, there is a good chance it is contaminated with asbestos, a harmful carcinogen. Asbestos was once a widely used material in home construction. For example, it was used in floor coverings, insulation, cement, ceiling tiles, walls and pipes.
One product that many people might not realize could contain asbestos is vermiculite. Vermiculite is a naturally occurring fiber, like asbestos. Pure vermiculite is generally considered nontoxic, but it can be contaminated with tremolite asbestos. Vermiculite was commonly used in home insulation products and for gardening purposes.
What does vermiculite insulation look like?
Vermiculite insulation is often used in attics. It is a pour-in product, usually light-brown, gold or gray in color. It is pebble-like, often with shiny flakes like mica. It may also contain accordion-like pieces. Often times, you can find it poured into low areas and voids in your attic. If you retained the insulation’s packaging, you may be able to identify the substance as vermiculite. A common brand was Zonolite.
Should I remove vermiculite insulation in my home?
No, if you suspect your home contains vermiculite insulation you should contact a licensed asbestos abatement contractor to determine whether your home is safe or if removal is prudent. Asbestos is most dangerous when it is disturbed and becomes airborne. If the vermiculate insulation in your home is tainted by asbestos, disturbing it could cause microscopic asbestos fibers to enter the air, where it can be breathed in and damage the lungs.
There is no safe level of asbestos exposure. Any amount of exposure could later cause damage, disease and even cancer.
The Minnesota Department of Health strongly recommends hiring a licensed asbestos contractor to remove anything you suspect may contain asbestos. Licensed contractors have the personal protective equipment necessary to make removal safe. They have access to encapsulation and removal techniques that you do not. And, they are able to perform air monitoring during the project. Overall, hiring a professional is the safest way to rid your home of asbestos.
Is it in my garden?
According to an EPA study, asbestos can be found in vermiculite products used in gardening. The primary asbestos contamination occurs in unmixed vermiculite, although some pre-mixed potting soils contain asbestos, too. To limit the possibility of exposure to asbestos-laden vermiculite, use pre-mixed potting soil, which usually contains less vermiculite and more moisture. It is also best to keep soil products moist during use to reduce the amount of airborne dust.
The good news is that the Minnesota Department of Health considers the risk of asbestos exposure through occasional contact with vermiculite gardening products to be low. However, greenhouse workers who have daily contact with vermiculite products are at higher risk.
Despite the low risk of asbestos exposure, it is a good idea to limit your use of vermiculite in gardening. Consider alternatives like peat, perlite, bark or sawdust. If you do use vermiculite, only handle it outdoors or in a well-ventilated area. Try to avoid getting it on your clothing and shoes, and if you do, try to avoid bringing the vermiculite into the house.