01. Where Asbestos Is Found
Where Does Asbestos Come From?
Asbestos is found in naturally occurring deposits around the world. Asbestos deposits are located across the United States, mainly in the western U.S. and eastern coastal states.
Although asbestos mining was prominent throughout the mid to late 1900s, the last asbestos mine closed in 2002. Currently, imports from Russia are the main source of asbestos for the United States.
Did You Know?
- Asbestos deposits can be found around natural talc and vermiculite deposits. As a result, talc and vermiculite can become contaminated with asbestos fibers.
- The vermiculite mines in Libby, Montana were contaminated with asbestos, affecting thousands of residents.
Asbestos Mining in the United States
Asbestos mining in the United States reached its height in the late 1960s and early 1970s. There were more than 100 operating mines.
Open-pit mining was originally the main practice for removing asbestos from the ground in the United States. Once removed, asbestos manufacturers processed the mineral to create asbestos-containing materials (ACMs).
Asbestos Mining and Milling Process
- Asbestos is located near the earth’s surface, allowing miners to work above ground.
- Miners remove the first layer of earth, typically by blasting or drilling.
- Asbestos miners then remove the ore from the earth.
- Millers crush, fiberize, screen, aspirate and grade the ore. This process removes asbestos fibers for use.
- Asbestos manufacturers can then incorporate asbestos fibers into a wide range of products.
The process of removing the earth’s top layer to mine ore at the surface is referred to as open-pit mining. The drilling and blasting during open-pit mining often released dangerous fibers and toxins into the air. As a result, miners, workers and residents near the mines were at risk of asbestos exposure. Those exposed risk illnesses such as mesothelioma and other asbestos cancers.
By the late 1970s, miners practiced a new method for removing ore. Miners incorporated wetting agents into the process. Wetting the ore helped prevent the release of fibers. Workers then crushed, sized, screened and dewatered the ore prior to shipment. Public health officials tasked with monitoring emissions noted the wetting technique as a safer alternative.
Is Asbestos Still Mined Today?
Asbestos mines are no longer in operation in the United States. Asbestos mining reached a peak in the late 1960s and early 1970s. Once the dangers of exposure became widely recognized, production gradually decreased.
|Timeline of Asbestos Mining in the United States|
|Year(s) of Production||Amount of Asbestos Mined*|
|Late 1960s – early 1970s||More than 299 million pounds|
|1987||112 million pounds|
|1989||37 million pounds|
|1993||28 million pounds|
|1997||15.4 million pounds|
|1998||13.2 million pounds|
|2002||Last asbestos mine closed|
*Data from the Agency for Toxic Substances and Disease Registry
Although the last asbestos mine closed in 2002, other countries continue to mine the mineral. Asbestos is not fully banned in the United States and can be imported under certain restrictions.
02. Types of Asbestos
Types of Asbestos
There are six main types of asbestos: chrysotile, actinolite, amosite, anthophyllite, crocidolite and tremolite. Each type belongs to the serpentine or amphibole asbestos mineral family. Chrysotile asbestos is the only serpentine type. All others are classified as amphibole asbestos.
All asbestos is fibrous. The main difference between serpentine and amphibole asbestos is fiber appearance. Serpentine fibers are long, curly and pliable. Amphibole fibers are short, straight, needle-like and stiff.
What Does Asbestos Look Like?
- Individual fibers are microscopic and not visible to the naked eye.
- Color differs based on asbestos type.
- Fiber shape differs based on mineral type.
- Most fibers are sharp and needle-like.
Actinolite asbestos is typically dark brown with sharp needle-like fibers. Actinolite is also made up of other minerals, including calcium, magnesium, iron and silicon.
Though this type of asbestos is rare, the following products have contained actinolite asbestos:
Amosite asbestos, or “brown asbestos,” has sharp, brittle and needle-like fibers. Amosite is particularly resistant to heat and flame. As a result, amosite is common in construction materials for fireproofing.
Amosite makes up around 5% of asbestos use in buildings throughout the United States. Amosite asbestos was also prevalent throughout the shipyard industry.
In a study of 144 shipyard workers and insulators, amosite was present in the lungs of each worker. Researchers noted tremolite and chrysotile fibers in most individuals. However, amosite asbestos was the most prominent fiber type.
According to the Environmental Protection Agency (EPA), amosite is the second most commonly used asbestos type in the United States.
The following products have contained amosite asbestos:
- Cement sheets
- Thermal insulation
- Fireproof products
- Chemical insulation
- Electrical insulation
- Pipe insulation
- Insulation boards
Anthophyllite asbestos is brown or yellow with long, needle-like fibers. Anthophyllite commonly contains magnesium and iron.
Anthophyllite is one of the rarest types of asbestos and not commonly used in commercial goods. The fibers have been found in cement and insulation materials on rare occasions.
Chrysotile asbestos, or “white asbestos,” has long, curly fibers that wrap around themselves. The fibers weave easily together into fabric.
Chrysotile is the most common type of asbestos used in the United States. An estimated 90 – 95% of asbestos in buildings in the U.S. and Canada contain chrysotile.
Chrysotile asbestos was frequently incorporated into construction materials and automotive parts.
Chrysotile was also common on Navy vessels. Navy ships often contained insulation made with chrysotile asbestos. The mineral was ideal because it was lightweight and incombustible.
The following products have contained chrysotile asbestos:
- Roofing materials
- Brake linings
- Brake pads
- Disk pads
Crocidolite, or “blue asbestos,” has very fine, sharp fibers. Due to the small size and brittle nature of crocidolite fibers, they are particularly easy to inhale. Some studies show crocidolite may be responsible for more asbestos-related illnesses and deaths than the other types.
Crocidolite asbestos is not as heat resistant as other asbestos types. As a result, it was rarely incorporated into commercial goods. In rare instances, crocidolite is in cement, tiles and asbestos insulation.
Tremolite asbestos ranges from a milky white to dark green color. Tremolite has straight, sharp fibers and is predominantly composed of magnesium. This type was not frequently used in product manufacturing. However, tremolite fibers have contaminated vermiculite and talc deposits. Research shows tremolite likely led to contamination of the W.R. Grace vermiculite mine.
Tremolite talc contamination was recently an issue in children’s makeup. Samples of children’s cosmetic kits tested positive for tremolite asbestos.
The following products have contained tremolite asbestos:
- Plumbing materials
- Talc-based cosmetics
03. Most Dangerous Type
What Type of Asbestos Is the Most Dangerous?
Some studies suggest amphibole asbestos is more dangerous than chrysotile. The Centers for Disease Control and Prevention (CDC) notes amphibole fibers can stay in the lungs for longer periods of time. However, research regarding the most dangerous type of asbestos is inconclusive.
Is All Asbestos Dangerous?
Despite studies finding varying risks associated with asbestos types, all asbestos is dangerous. Exposure to any type of asbestos can lead to cancers and other illnesses.
The Occupational Safety and Health Administration (OSHA) does not regulate asbestos types differently based on perceived danger. Evidence was submitted to OSHA in an attempt to prove chrysotile is less dangerous than other amphibole types. OSHA emphasized the decision to treat the fibers similarly with the following reasons:
- The evidence shows a similar correlation between chrysotile and amphibole potency in relation to lung cancer and asbestosis.
- Evidence supporting chrysotile as less toxic than other types was primarily associated with mesothelioma cases.
- This evidence was unpersuasive and did not justify regulating chrysotile less strictly.
Studies continue to research the level of risk associated with each asbestos type.
Friable vs. Non-Friable Asbestos
Asbestos materials are either friable or non-friable. Friability depends on how easily the material can be broken down by hand. Friable products typically pose more of a health risk than non-friable asbestos.
- Can crumble or break by hand
- Fibers release easily and pose a greater health risk than non-friable asbestos
- Example products: Spray-on insulation, thermal insulation and other spray-on coatings
- Cannot crumble or break by hand but may be disturbed by sawing, sanding or cutting
- Poses less of a health risk than friable asbestos if undisturbed or securely contained within other materials
- Example products: Vinyl floor tiles, roofing felt, transite paneling and window glazing
Non-friable asbestos may not pose a risk if properly contained. However, individuals should treat any asbestos product as a potential health risk. Home renovations, natural disasters and other incidents can easily present asbestos exposure risks.
04. Asbestos Uses
What Is Asbestos Used For?
Asbestos was used in a variety of products mainly for heat resistance and fireproofing. Asbestos use peaked towards the late 1900s. The mineral was used in insulation, cement, flooring, roofing and fireproof products. This practice was popular from the 1930s to the 1970s. In 1979, asbestos regulations forced manufacturers to use safer asbestos alternatives.
Is Asbestos Still Used in the United States Today?
Asbestos is not yet fully banned in the United States. Asbestos mining is no longer allowed, but the mineral can be imported. Asbestos-containing products are still in use throughout the U.S. Some products may also legally be manufactured with small amounts of the mineral.
Two major concerns about asbestos in the United States include:
- Older asbestos-containing products can become exposed from damage, wear-and-tear or other disturbances. For example, buildings and homes built before 1979 likely contain asbestos materials that haven’t been replaced or removed.
- Small amounts of asbestos may be allowed in some consumer products.
Asbestos was once used in thousands of products. Regulations prevent many new products from containing the mineral, but some may legally contain low levels of asbestos. Manufacturers are also not required to disclose asbestos in the ingredients list if there is less than 1% asbestos.
Common asbestos products include:
- Floor tiles
- Ceiling tiles
Historically, there are many occupations that have put workers at risk of asbestos exposure. The term “asbestos occupation” refers to any job potentially exposing workers to asbestos fibers.
Asbestos occupations involve:
- Manufacturing products with raw asbestos (Example: Using asbestos to create asbestos cement)
- Working with materials containing the mineral (Example: Repairing vehicles with asbestos-containing brakes)
- Working in buildings containing the mineral (Example: Teachers working in classrooms with aging asbestos ceiling tiles)
The main concern with asbestos in the workplace is if fibers become airborne. Individuals can then breathe in or swallow the fibers. Many jobs required workers to sand, cut or repair asbestos products. This often created asbestos dust. Asbestos building materials may also face wear and tear over the years, which can expose fibers in classrooms, public buildings and other structures.
Asbestos particles are not typically visible to the naked eye and are odorless. As a result, many workers are unaware of their exposure.
Secondary Asbestos Exposure
Individuals are at risk of secondhand exposure if they come into contact with asbestos fibers from someone else who was exposed. For example, women and family members were often exposed when men brought asbestos fibers home on their clothing. Men most frequently held high-risk asbestos occupations.
“When I was a little girl, my dad worked construction. He would come home from work, his jacket covered in dust. His jacket would be white, crusty from the drywall dust that he would be sanding off the walls. Anything that I had to do outside, I liked wearing my dad’s coat. It was just, you know, unbeknownst to us that it was chock full of asbestos.”
-Heather Von St. James, Mesothelioma Survivor
05. Exposure Health Risks
What Are the Health Risks of Asbestos?
Asbestos fibers are dangerous when they are inhaled or swallowed and become embedded in organ linings and tissues. Asbestos-related diseases include mesothelioma, lung cancer, asbestosis and other illnesses.
Asbestos cancers include mesothelioma, lung cancer, laryngeal cancer and ovarian cancer. Studies have found correlations between asbestos and several other cancers, such as breast cancer and colon cancer.
Due to their needle-like structure, fibers can easily embed in organ linings and tissues. This can then cause irritation, mutation and cancer. Long-term exposure to asbestos fibers increases the risk of asbestos cancer.
Asbestos diseases include asbestosis, pleural thickening, pleural plaques and other conditions. These illnesses are typically caused by prolonged exposure to asbestos fibers. However, no amount of exposure is safe, including short-term exposure.
Asbestos diseases can also be an indicator of asbestos cancer.
Resources for Mesothelioma Patients
06. Asbestos Safety Tips
How to Avoid the Dangers of Asbestos
People can avoid the dangers of asbestos by:
- Understanding what products are likely to contain asbestos
- Seeking professional help for asbestos handling and disposal
- Using asbestos alternatives when possible
1. Identifying Asbestos Products
Individuals cannot easily identify asbestos products on their own. However, there are professionals trained at identifying and confirming the presence of asbestos.
Most asbestos products were manufactured prior to 1979. Items facing high temperatures or friction are likely to contain the mineral. Homeowners with houses built prior to 1979 should be particularly careful.
Some products may be deemed “safe” if asbestos is properly contained. Health risks emerge when the fibers become exposed. Asbestos in the home could become a health risk when conducting repairs or renovations. Asbestos materials may also become exposed during a natural disaster or after wear and tear.
2. Safely Handling and Removing Asbestos
Individuals should never touch, move or dispose of asbestos-containing material on their own. Asbestos abatement professionals are trained and certified in identifying, handling and properly disposing of the material.
Asbestos materials cannot be disposed of in normal trash bins and waste sites. They require specific packaging and labeling before disposal at designated locations.
3. Finding Alternatives to Asbestos
There are many asbestos alternatives. These options have similar properties and less severe health effects. Asbestos alternatives may include:
- Form/Composition: Woven cloth typically sold in large sheets that can be cut to the desired size
- Qualities: Offers chemical, heat and abrasion resistance
- Products: Incorporated in products such as fireproof gear and thermal barriers
- Form/Composition: Made from plant-based materials, such as shredded newspaper, wood or leaves
- Qualities: Chemically treated to improve heat and fire resistance
- Products: Incorporated in products such as insulation
- Form/Composition: Often available in foam blocks, foam sheets or spray-on foam
- Qualities: Molds to fill cracks and gaps
- Products: Acts as insulation or filler for thermal products
- Form/Composition: All-natural combinations of products such as wheat flour, rice flour, cork flour or wood flour
- Qualities: Often mixed with a binding agent
- Products: Typically poured into cracks and crevices for sealing and insulating
Asbestos substitutes may present other health problems, such as lung disease. Before using an asbestos alternative, individuals should understand the associated benefits and risks.
07. Asbestos Claims
If individuals have been exposed to asbestos and developed a related illness, they may be able to file a claim. Asbestos claims can help with treatment costs and loss of income. Asbestos victims should discuss their exposure, diagnosis and financial needs with an experienced lawyer to understand their options.