Types of Asbestos

Understanding the Different Types of Asbestos Matters

Asbestos is a commercial and legal term encompassing several minerals with unique properties and risks. The Asbestos Hazard Emergency Response Act of 1986 classifies 6 minerals as commercial types of asbestos. These types of asbestos were once commonly used in manufacturing. Knowing the differences is key to spotting asbestos. It can prevent serious diseases like cancer.

While all types of asbestos are dangerous, some are more hazardous than others. Their fibrous structure and mechanisms keep them stuck in the body. Knowing these differences can assist in identifying the severity of exposure risks.

A recent U.K. study used mass spectrometry on mesothelioma samples. It identified different types of asbestos. Mass spectrometry measures the molecular weight of compounds to identify them. Researchers said the discovery can help diagnose mesothelioma. It can also prove asbestos exposure caused it.

Two Main Categories of Asbestos

Asbestos is classified into two types: Serpentine and amphibole. The types differ in the shape and makeup of the asbestos fibers. These factors are key in determining their danger to human health.

Serpentine Asbestos

Serpentine asbestos has curly fibers made up of sheets of crystals. Chrysotile is the only type of asbestos in the serpentine family. It has historically accounted for more than 95% of all asbestos used worldwide.

Deposits of serpentine asbestos occur in many countries, including Canada, Russia, Brazil and Kazakhstan. Repeated exposure to chrysotile asbestos causes respiratory diseases and cancer. These diseases include asbestosis, lung cancer and mesothelioma.

Amphibole Asbestos

Amphibole asbestos has straight, needle-shaped fibers. This group has 5 types of asbestos: amosite, crocidolite, tremolite, anthophyllite and actinolite. Studies show lower exposure to amphibole asbestos causes cancer more than serpentine asbestos. Recent research indicates that exposure to amphibole asbestos causes severe autoimmune conditions in addition to cancer and respiratory conditions.

Amosite and crocidolite are the most commercially valuable forms of amphibole asbestos. Anthophyllite, tremolite and actinolite are noncommercial forms. Companies have mined amphibole asbestos in Australia, Canada, Finland, Italy, South Africa and the U.S.

Chrysotile Asbestos (White Asbestos)

Chrysotile asbestos, the most common type of asbestos, is linked to diseases like mesothelioma and lung cancer. Also known as “white asbestos,” it was used in most U.S. asbestos products made in the 20th century. The U.S. and Canada were once significant producers of the toxic mineral.

Construction materials are the most common source of chrysotile asbestos. Small amounts of amphibole asbestos are often found in chrysotile deposits. These trace amounts increase its toxicity. But exposure to only chrysotile asbestos is still medically risky.

NIOSH says people should treat chrysotile asbestos like other dangerous asbestos. In March 2024, the EPA announced a ban on chrysotile asbestos. It will roll out in phases over 12 years, giving companies time to establish replacements.

Amosite Asbestos

The U.S. Environmental Protection Agency says amosite, or brown asbestos, is the second most commonly used type in the country. Its fibers are long, straight and brittle, with a distinctive rod-like shape. According to the American Cancer Society, amosite asbestos creates a higher risk of cancer than common chrysotile asbestos.

In its natural state, amosite is known as grunerite. It was mainly mined in South Africa. The name “amosite” comes from the acronym for the Asbestos Mines of South Africa.

Crocidolite Asbestos (Blue Asbestos)

Crocidolite is the most dangerous asbestos. It may cause more mesothelioma deaths than any other type. Its fibers are extremely thin, allowing them to lodge more easily in lung tissue.

The mineral is blue, from light to deep blue or blue-gray. It has fine, fibrous crystals. The most common mining sites for this type of asbestos were in Bolivia, Australia and South Africa.

Tremolite Asbestos

Tremolite asbestos can be white, gray, green, or translucent. Impurities in its composition change its color.

Tremolite asbestos is often extracted when mining other minerals like vermiculite and talc. Mining nephrite jade, used for gemstones, poses a risk. Nephrite is made of tremolite and actinolite.  

Unlike the commercial forms of asbestos, manufacturers rarely intended to include tremolite in their products. Even incidental amphibole contamination is still hazardous enough to cause asbestos-related illnesses.

Anthophyllite Asbestos

Anthophyllite asbestos typically appears in shades of gray, green or brown. It has long, thin fibers that are brittle and can easily break into microscopic pieces.

Anthophyllite is one of the rarest types of asbestos and doesn’t have a long history of commercial use. The mining of this mineral began in Finland. Various other countries around the world mined smaller deposits. This mineral is sometimes found in deposits of talc and vermiculite.

Actinolite Asbestos

Actinolite asbestos is a less common type of asbestos. Its fibrous, elongated crystals are green to gray. They can be silky or shiny. The long, needle-like amphibole asbestos fibers are more durable. They can penetrate deeper into lung tissue, raising their cancer risk.

Actinolite asbestos deposits have been found in the U.S., Canada, Finland and Australia. It was commonly used in insulation materials, particularly in high-temperature applications.

How to Identify the Types of Asbestos in Your Home or Workplace

Identifying asbestos types in homes or workplaces prevents mesothelioma and other asbestos-related diseases. Asbestos can be present in many building materials and pose severe health risks without proper identification. Only professionals can readily identify asbestos. It is often colorless, odorless, and too small to see with the naked eye.

Professionals use specialized tests to check for asbestos. These tests include air sampling, bulk material testing, and microscopic analysis. These tests can accurately identify asbestos and its type. This allows for safe removal or containment.

Asbestos abatement expert and industrial hygienist Tony Rich says that in his experience as a building inspector, “The presence of asbestos in residential settings is often dependent upon the age of the structure. The older the home, the more likely asbestos can be found.”

Asbestos Bans and Regulations by Type

Asbestos regulations vary globally and often depend on the type of asbestos. Most countries, including the U.S., ban asbestos use. This includes a ban on amphibole types, like crocidolite and amosite. Some exemptions remain for chrysotile asbestos. It is allowed in certain products under specific conditions in the U.S. and Canada.

Many countries ban all types of asbestos. The U.S. has partial bans on some products and uses under the Toxic Substances Control Act (TSCA). Globally, conventions like the Rotterdam Convention require labeling and control over chrysotile asbestos.

Despite its dangers, chrysotile asbestos is exempt from full bans in some regions. The exemptions allow limited use in industries like cement and automotive production. But these exemptions are continually scrutinized and have been reduced over time.

Common Questions About Asbestos Types

Is all asbestos dangerous?

While some types of asbestos may be more hazardous than others, all are dangerous. Leading health agencies, including the U.S. Department of Health and Human Services, the EPA and the International Agency for Research on Cancer, classify all types of asbestos as cancer-causing substances.

All the identified forms of asbestos can cause asbestosis, malignant mesothelioma, lung cancer, ovarian cancer, laryngeal cancer and other serious diseases.

Where else can asbestos be found?

Asbestos can be found in various minerals, including talc and vermiculite, which are commonly used in everyday products. Talc, used in products like baby powder, cosmetics, paint and ceramics, may naturally contain asbestos, posing a risk of exposure. This has led to numerous legal cases involving talc-containing products contaminated with asbestos.

Vermiculite, another mineral used in insulation and soil improvement, can also be contaminated with asbestos, especially when sourced from mines like the one in Libby, Montana, which contained tremolite asbestos. In addition to these minerals, asbestos has been mined intentionally for its properties and can still be found in older construction materials, such as insulation, roofing, and flooring.

Have all types of asbestos been banned?

The U.S. is banning chrysotile asbestos, but the law doesn’t ban all types of asbestos. More than 50 countries have banned the 6 types of asbestos completely.

Are there differences in the handling or removal procedures for different types of asbestos?

No, asbestos laws don’t differ based on the types of asbestos fibers. Laws instead vary depending on how dangerous the asbestos-containing material is to remove. The most dangerous categories of asbestos product removal require increased safety measures and training to perform.

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