Vermiculite is an insulating and fire-resistant mineral found in many homes built between 1930 and 1990. Vermiculite is still sold today, mainly for agricultural and horticultural use. It comes in small pellets, such as those used for wood stoves.
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Is there still asbestos in vermiculite?
Vermiculite and gardening use Not all vermiculite products contain asbestos, but some do. An EPA study showed some vermiculite products contain low levels of asbestos. Asbestos is found primarily in the unmixed vermiculite product although some was found in pre-mixed potting soils.
What percentage of vermiculite has asbestos?
The asbestos present in vermiculite is not bound up like it typically is in a building material and therefore the risk is potentially greater, even at percentages well below 1%. Unfortunately the 1% rule still predominates and often times a Qualitative result will not suffice no matter how much sense it makes.
Is vermiculite still mined?
Large commercial vermiculite mines currently exist in the United States, Russia, South Africa, China, and Brazil.
When did they stop putting asbestos in vermiculite?
Vermiculite, a naturally occurring mineral was, until 1990, mined from the same ore deposits as the deadly mineral fiber asbestos. Asbestos ore is made up of long, thin fibers that can only be seen through a microscope.
Is it safe to live in a house with vermiculite?
The EPA recommends that vermiculite insulation be left undisturbed. Airborne asbestos fibers present a health risk through inhalation, so the first step is to not disturb the material, which could release fibers into the air.
How do I know if my vermiculite has asbestos?
How can I tell if my vermiculite insulation contains asbestos? The majority of all vermiculite insulation pro- duced before 1990 used contaminated vermicu- lite from Libby. Asbestos fibers in vermiculite are too small to be seen by the naked eye. Only a trained technician using a microscope can see asbestos fibers.
When was vermiculite stopped being used?
1990Vermiculite is a mineral that was used for insulation. If your home was built before 1990, you might have vermiculite insulation in your walls or attic.
What is vermiculite used for today?
It's used in the building industry, the car industry and in packaging. For use in horticulture, it's sold as lightweight, absorbent brown-gold flakes. Vermiculite can absorb three or four times its weight in water and also attracts various plant nutrients such as potassium, magnesium and calcium.
What can I use instead of vermiculite?
Finely ground pine bark, also called “pine fines,” is a principal ingredient of most potting mixes. As an alternative to vermiculite, pine fines also offer water-retentive qualities, especially with smaller particle sizes. Cotton gin waste includes gin leavings, such as stems, leaves and hulls.
What happens if you breathe in asbestos once?
Is One-Time Exposure Harmful? It is possible to develop an illness such as asbestosis, mesothelioma, pleural effusions or lung cancer after a one-time exposure to asbestos if the exposure was significant enough to lead to asbestos particles lodging in the body's tissues.
Can you touch vermiculite?
Vermiculite is a naturally occurring mineral that is perfectly safe when pure.
What are the dangers of vermiculite?
If vermiculite is disturbed, it could cause tiny, needle-like asbestos fibers to become airborne. Asbestos in the air can be inhaled and cause lung damage. If asbestos is not in the air, it is not dangerous to your lungs.
What is an acceptable percentage of asbestos?
No amount of asbestos is considered safe. Products that contain greater than 1 percent of asbestos minerals are considered to be asbestos-containing. The more asbestos you are exposed to, the more likely you are to get an asbestos disease.
Can vermiculite be tested for asbestos?
Currently, there are specific technical issues involving vermiculite sampling that can complicate testing for the presence of asbestos fibers and interpreting the risk from exposure. EPA and ATSDR are not recommending at this time that homeowners have vermiculite attic insulation tested for asbestos.
What percentage of asbestos is in cement?
(see MDHS 100). As the cement, contains approximately 10 – 13% of asbestos by weight, the larger asbestos bundles are usually readily visible by eye especially at newly fractured edges.
How much exposure to asbestos will cause mesothelioma?
There is no safe amount of asbestos exposure. Even one-time asbestos exposure can lead to asbestos-related diseases such as pleural thickening, lung cancer or mesothelioma.
What is exfoliated vermiculite used for?
The mixture helps retain air, plant food, and moisture, releasing them as the plant requires them. These mixes were pioneered by Boodley and Sheldrake. Exfoliated vermiculite is also used as a growing medium for hydroponics.
Where is vermiculite found?
Large commercial vermiculite mines currently exist in the United States of America, Russia, South Africa, China, and Brazil .
What is vermiculite dispersions?
As a constituent of a coating: vermiculite dispersions are typically either chemically or physically very finely delaminated vermiculite in a fluid medium. These dispersions can be used to make vermiculite 'paper' sheets by pouring them onto a piece of smooth, low surface-energy plastic, and allowing to dry.
How long does it take for calcium silicate to cure?
This is then dewatered by pressing or by using one of the Fourdriner/Magnani/Hatschek processes to form a flat board which is then heat cured under pressure (typically 10–15 bar) for periods of up to 24 hours.
Where was the first vermiculite mine?
Controversy over health risks. The largest and oldest vermiculite mine in the United States was started in the 1920s, at Libby, Montana , and the vermiculite was sold under the commercial name Zonolite. The Zonolite brand and the mine were acquired by the W. R. Grace and Company in 1963.
What is the color of vermiculite?
From Wikipedia, the free encyclopedia. White or yellowish, translucent, shiny, light-brown or greenish in color, in some cases. For example, palabora vermuculite. Vermiculite is a hydrous phyllosilicate mineral which undergoes significant expansion when heated. Exfoliation occurs when the mineral is heated sufficiently, ...
Is vermiculite insulation safe?
The United States government estimates that vermiculite was used in more than 35 million homes, but does not recommend its removal. Nevertheless, homes or structures containing vermiculite or vermiculite insulation dating from before the mid-1990s—and especially those known to contain the "Zonolite" brand—may contain asbestos, and therefore may be a health concern.
What Is Vermiculite Used For?
Vermiculite is a lesser-known product that was typically used as attic insulation in homes built between the 1940s-1980s. It is a naturally occurring compound, with light-weight and fire-resistant characteristics. Although it can be considered a dangerous material to have in your home, not all of it is problematic. However, the majority of it was mined in Libby, Montana (under the brand name Zonolite) and found to contain asbestos — a very serious health hazard that also devalues a home’s overall worth. Vermiculite mined in other locations is generally considered safe, although the stigma around it can still impact opinions of a home’s value.
Is vermiculite a hazard?
On its own, pure vermiculite generally isn’t a health hazard, but if it contains asbestos it can present serious health risks. When disturbed, asbestos becomes airborne (also known as “friable”) and can easily be inhaled. Then the fine fibers attach to the lungs creating a few different problems – some more serious than others.
Why is vermiculite bad?
Nearly all vermiculite contains asbestos, which can cause lung cancer when inhaled. While it’s true that undisturbed, encapsulated asbestos doesn’t pose a health risk, the asbestos in vermiculite insulation isn’t encapsulated and can easily become airborne during cleaning, maintenance or remodeling. And, the type of asbestos found in vermiculite—called amphibole—is even more hazardous than the chrysotile asbestos that was more commonly used in the U.S.
Where does vermiculite come from?
Up to 85 percent of all vermiculite insulation in the U.S. came from a mine in Libby, Montana, sold under the name Zonolite.
Can you leave vermiculite alone?
Federal guidelines are weak. The EPA (Environmental Protection Agency) recommends that if you have vermiculite, it’s best to assume it contains asbestos and leave it alone. You can have it tested for asbestos, but here’s the rub. The EPA defines an asbestos-containing material (ACM) as having greater than 1 percent asbestos.
What Is Vermiculite?
Vermiculite is a naturally occurring mineral that takes the form of glossy flakes, varying in color from dark gray to sandy brown. These flakes, which are more specifically a hydrated magnesium iron aluminum silicate mineral, get heated up in a purpose-built a commercial furnace, where they then expand and take on a concertina shape, almost like a tiny accordion.
Why is vermiculite important?
Moisture control is especially important for young plants, who have weaker root systems, which more easily succumb to rot. Vermiculite helps to prevent this problem as it retains moisture, which is released when the roots need it, meaning you won’t have to keep such a close eye on watering the seedlings or cuttings.
How Does Vermiculite Compare to Some Other Mineral Additives?
Perlite is known to be more effective at aerating soil than vermiculite, while vermiculite is better at retaining moisture. It has a more expansion potential and is, therefore, able to hold on to greater amounts of moisture.
How to use vermiculite in soil?
You will often hear the phrase ‘improve your soil before planting,’ but how do you actually do this in practice? Vermiculite is your answer. Use around half the volume of the soil in vermiculite, and work it deep into the soil. The vermiculite will drastically improve the soil’s aeration, allowing plants to grow much better. It will also retain the necessary moisture and nutrients to help feed the plant.
How many sizes of vermiculite are there?
Once the exfoliation is complete, the finished product will vary in looks, depending on its size. There are four sizes of vermiculite available, with the largest size having an obvious concertina shape. The smallest sizes to the human eye just look like large grains of sand.
What is the process of exfoliating vermiculite?
This process is called ‘exfoliation.’. Exfoliated vermiculite transforms into small strands that look like worms, and this is how vermiculite got its name, from the Latin word ‘vernacular,’ which translates roughly to ‘to breed worms.’. Once the exfoliation is complete, the finished product will vary in looks, depending on its size.
Can you use vermiculite to propagate cuttings?
Whether used alone, or in a mix, propagating a cutting with vermiculite will promote anchorage for new roots, and speed up root growth. If you want to encourage a more rapidly rooting cutting and a higher propagation success rate, vermiculite is the preferred material to use ( The Vermiculite Association ).
What is vermiculite made of?
What is Vermiculite. Vermiculite is a naturally-occurring mineral composed of shiny flakes, resembling mica. When heated to a high temperature, flakes of vermiculite expand as much as 8-30 times their original size.
What is expanded vermiculite?
The expanded vermiculite is a light-weight, fire-resistant, and odorless material and has been used in numerous products, including insulation for attics and walls. Sizes of vermiculite products range from very fine particles to large (coarse) pieces nearly an inch long.
What color is vermiculite insulation?
Vermiculite insulation is a pebble-like, pour-in product and is usually gray-brown or silver-gold in color.
Is vermiculite asbestos?
You should assume that vermiculite insulation is from Libby and treat the material as if it contained asbestos by not disturbing it or by using a trained professional if it needs to be removed. Since the Libby mine was estimated to be the source of over 70 percent of all vermiculite sold in the United States from 1919 to 1990 and vermiculite from Libby was contaminated with asbestos, further testing is not necessary to take the appropriate precautions. While you can hire a trained professional to test your attic for asbestos, this may be expensive and, depending on the methods used, might give you erroneous results. We do not recommend that you open your walls to check for vermiculite.
Is vermiculite asbestos contaminated?
Concerns about Asbestos-contaminated Vermiculite Insulation. A mine near Libby, Montana, was the source of over 70 percent of all vermiculite sold in the United States from 1919 to 1990. There was also a deposit of asbestos at that mine, so the vermiculite from Libby was contaminated with asbestos. Vermiculite from Libby was used in the majority ...
Can you leave vermiculite in the attic?
Leave vermiculite insulation undisturbed in your attic or in your walls. Do not store boxes or other items in your attic if it contains vermiculite insulation. Do not allow children to play in an attic with vermiculite insulation. Do not attempt to remove the insulation yourself. Hire a professional asbestos contractor if you plan to remodel ...
How to use vermiculite for plants?
Add the vermiculite to your soil for lightening and conditioning in conjunction with compost or peat, or alone. This strategy accelerates the growth and development of the plant’s root systems. Using vermiculite for your plants growing medium also helps the plant with absorbing minerals like potassium, ammonium, magnesium, and calcium from the soil.
Why do you need to water vermiculite?
Vermiculite suits growing hot climates, where gardeners need to water their flowerbeds frequently to ensure the soil is moist. Adding vermiculite to your land in these types of goring conditions ensures that the roots of your plants are always airy and moist.
How to transplant vermiculite?
Those gardeners wishing to transplant using vermiculite as the substrate of choice must dig a hole 6-inches wider than the plant’s root system. Mix the vermiculite into the excavated earth, and then return it to the hole.
Can vermiculite be used in garden?
If you’re dealing with these issues in your garden, adding vermiculite to your soil is an excellent option. However, while many gardeners may have seen the stuff lying around the garden center, many don’t know how to use it in the garden.
Can vermiculite be added to clay soil?
If you add vermiculite to clay soils, it may become waterlogged and soggy, reducing the airflow around the roots of the plant. Some soil mixtures feature airy components like coconut peat, might not get any benefit from the addition of vermiculite as a soil amendment.
Is perlite good for garden soil?
It’s common for garden centers and nurseries to include the use of perlite in soil mixes. Vermiculite offers the gardeners the same properties, but with better moisture retention. While vermiculite may not provide as much aeration to the roots of the plant, it’s the top-choice soil amendment where moisture retention is a concern.
Can you add vermiculite to potting soil?
You can add your vermiculite directly to flowerbeds in the garden, or use it as an amendment in potting soils. Adding vermiculite to the spoil mix improves moisture retention and aeration of the soil, allowing for the rapid growth of the plant’s roots.
What tool do home inspectors use to find vermiculite?
Their hand-held spectrometer can save serious time for inspectors while providing peace of mind for homeowners.
How to get rid of zonolite in a home?
Asbestos abatement professionals have the tools necessary to rid a home of Zonolite for good. If you spot Zonolite in a home, encourage the homeowner to schedule an appointment with an asbestos abatement company. In the meantime, minimize any exposure to the stuff when inspecting a property.
What is the Zonolite Attic Insulation Trust?
The Zonolite Attic Insulation Trust helps homeowners who have asbestos insulation get rid of it safely. They also help with re-insulation. The Trust will reimburse homeowners 55 percent of the cost of removal and new insulation.
Is zonolite safe for homes?
For years, Zonolite was used in the insulation of homes throughout the United States. While some believe the substance to be safe, a 2008 class-action lawsuit against W.R. Grace, owner of the Montana mine that produced Zonolite, came to a different conclusion. The court found that one percent wasn’t a strict enough standard.
Is vermiculite insulation dangerous?
The Fine Line of One Percent. The EPA says that vermiculite insulation, which is the pebbly stuff found in attics of many older homes, is only risky if it contains more than one percent asbestos. That’s good news, because most Zonolite, a type of vermiculite insulation, falls into that category. For years, Zonolite was used in the insulation ...
Can you use vermiculite insulation in the attic?
In the meantime, homeowners should avoid using vermiculite-insulated attics as storage space. Children should be kept away from the attic, too. Anything that can disrupt the insulation in any way presents a new risk, so closing off the attic entirely is best – at least until the professionals can come in to do their part.
Is vermiculite harmless?
It might look harmless, but some vermiculite have a nasty personality. Much has been made about the danger of asbestos over the years. It seems you can’t flip through the channels or scroll through a website without seeing an advertisement for legal services for asbestos victims. While our society has become more educated about ...
What is vermiculite good for?
Another good thing about vermiculite is that it creates an insulating layer. The top layer of soil is thus kept moist for a long period, at the same time as light is let through. Perfect for seeds planting that are not allowed to dry out under any circumstances, at the same time needing a larger amount of light to start germinating. The material is also sterile, which means that disease or vermin can not keep up with just the speed. An extremely good product for plants that want to stand with their roots soaked in other words!
Can you sprinkle vermiculite over caudex?
In addition to these plants, I personally like to sprinkle a little vermiculite over a new caudex, regardless of variety. During their first weeks/months of life, they never want to be dry out, a task that is difficult to fulfill when the sun is on and the days are hot. By covering the soil with vermiculite, you create a perfect environment that is both light and moist.
Overview
Vermiculite is a hydrous phyllosilicate mineral which undergoes significant expansion when heated. Exfoliation occurs when the mineral is heated sufficiently, and commercial furnaces can routinely produce this effect. Vermiculite forms by the weathering or hydrothermal alteration of biotite or phlogopite. Large commercial vermiculite mines currently exist in the United St…
Occurrence
Vermiculite was first described in 1824 for an occurrence in Millbury, Massachusetts. Its name is from Latin vermiculare, "to breed worms", for the manner in which it exfoliates when heated.
It typically occurs as an alteration product at the contact between felsic and mafic or ultramafic rocks such as pyroxenites and dunites. It also occurs in carbonatites and metamorphosed magnesium-rich limestone. Associated mineral phases include: corundum, apatite, serpentine, …
Structure
Vermiculite is a 2:1 clay, meaning it has two tetrahedral sheets for every one octahedral sheet. It is a limited-expansion clay with a medium shrink–swell capacity. Vermiculite has a high cation-exchange capacity (CEC) at 100–150 meq/100 g. Vermiculite clays are weathered micas in which the potassium ions between the molecular sheets are replaced by magnesium and iron ions.
Commercial uses
This process involves mixing exfoliated vermiculite with inorganic bonding agents such as sodium silicate, cement (specific quantities), and other compounds, such as those containing potassium, to produce an 'earth damp' mixture. This material is then hydraulically pressed into shape in a mold and then heat cured at temperatures up to 180 °C for up to 24 hours, depending up…
Commercial manufacture of exfoliated vermiculite
In 2014, South Africa, Brazil, the US, and China were the top producers of mined, concentrated and unexfoliated vermiculite, with about 90% world share. South Africa's production is decreasing, while Brazil's is significantly increasing.
While some end processors and exfoliators of vermiculite specialize, with proprietary products sold in a wide variety of industries, some have more varie…
Fireproofing
Today spray-applied fireproofing materials use vermiculite, other industrial minerals, and expanded polystyrene, depending upon the exact commercial product. The ingredients for these products all have to meet stringent regulatory requirements, particularly in the US and Europe. In the past, vermiculite from the W. R. Grace mines in Libby, Montana, has been associated with asbestos. Therefore, old spray-applied fireproofing, pre-1991, may contain small quantities of asbestos. In …
Asbestos contamination
Although not all vermiculite contains asbestos, some products were made with vermiculite that contained asbestos until the early 1990s. Vermiculite mines throughout the world are now regularly tested for it and are supposed to sell products that contain no asbestos. The former vermiculite mine in Libby, Montana, did have tremolite asbestos as well as winchite and richterite (both fibrous amphiboles)—in fact, it was formed underground through essentially the same geol…
Controversy over health risks
The largest and oldest vermiculite mine in the United States was started in the 1920s, at Libby, Montana, and the vermiculite was sold under the commercial name Zonolite. The Zonolite brand and the mine were acquired by the W. R. Grace and Company in 1963. Mining operations at the Libby site stopped in 1990 in response to asbestos contamination. While in operation, the Libby mine may have produced 80% of the world's supply of vermiculite.