Asbestos refers to six naturally occurring fibrous minerals that have the ability to resist heat, fire and electricity. These properties of asbestos supported its use for many years in a number of different commercial and industrial settings, as well as in a wide range of consumer products.
Although its use has diminished in recent decades, there are still many products that contain asbestos, especially in older homes, schools and public buildings. The mineral has not yet been banned in the United States, although the U.S. Environmental Protection Agency (EPA) and other federal agencies have strict laws in place to help limit its use and prevent exposure. Asbestos is extremely hazardous when it becomes disrupted and airborne, as it is easily inhaled or ingested and can lead to many health concerns, including mesothelioma.
- Asbestos Products
- Find out what products in your home, vehicle, school or workplace could contain asbestos.
- Asbestos Companies
- Learn which companies used asbestos in their products and manufacturing processes.
Types of Asbestos
The word “asbestos” is a general term referring to a group of silicate minerals that have the same properties, including:
- Thin, fibrous crystals that can be easily broken and manipulated
- Resistance to fire, heat and electricity
- Sound absorption
All types of asbestos share these properties, though each individual type may vary in other facets, such as color and tensile strength. In general, asbestos is classified into two main families, serpentine and amphibole asbestos. Serpentine asbestos is noted for its “curly” fibers and accounts for 95% of all asbestos used. Amphibole asbestos consists of needle-like fibers that researchers consider to be more dangerous because it can take less exposure to lead to mesothelioma or other diseases. However, whether amphibole or serpentine, all types of asbestos are considered dangerous.
Actinolite asbestos is a variety of the subclassification of amphibole asbestos and, as such, its makeup and consistency is similar to other forms of this subset. Made predominantly of magnesium, actinolite asbestos is extremely rare and ranges in color from white to dark brown. Actinolite was not known to be used in asbestos products because of its rarity, but is known to be found in metamorphic rock. As with all forms of asbestos, actinolite is a known carcinogen that can cause mesothelioma cancer.
The commercial production of amosite, or “brown” asbestos, ended within the last decade and this type of asbestos is no longer mined. At one time, however, it was the second-most commonly used form of asbestos and, as a result, many individuals were exposed to it during its peak use. Amosite was employed as insulation in factories and buildings, as well as both an acoustical and anti-condensation material. Its use has been banned in most countries for approximately the last 30 years.
Anthophyllite asbestos, also known as “brown” asbestos, is composed predominantly of iron and magnesium. Its fibers are known to be long and flexible. Of the amphibole subclass, brown asbestos can be found in many talc mines and has been associated with some respiratory disorders. It is not conclusively associated with mesothelioma as other varieties of asbestos are. Because of its rarity, anthophyllite was not often used in consumer products, but could be found in some cement products and insulating materials.
Chrysotile, the most common type of asbestos and only kind that is still mined, was the most widely used in the world’s developed countries. Estimates show about 90 – 95% of all asbestos that remains in buildings in the U.S. and Canada is of this variety. Because it was so widely used, it accounts for the most health problems, though the companies that mine it continue to attest to its safety. Chrysotile is most often used in fireproofing and insulation products and was widely used aboard U.S. Navy ships during World War II and the Korean War.
Crocidolite asbestos was rarely used, and accounted for only 1.3% of all asbestos ever used in the United States. Crocidolite occurs in naturally-formed bundles that are long, sharp and straight. This "blue" asbestos is harder and more brittle than other types of the mineral and can break easily, releasing dangerous needle-like fibers that are easily inhaled. Crocidolite was only used in very limited, specialized applications, including acidic or corrosive environments.
As a form of amphibole asbestos, tremolite asbestos is associated with the development of malignant mesothelioma and other asbestos-related cancers. Like other varieties of asbestos, tremolite asbestos is composed predominantly of magnesium and can range from off-white to a dark green in color. Tremolite is particularly common in vermiculite deposits. Tremolite-contaminated vermiculite was responsible for the death of hundreds of miners in Libby, Montana who worked at the W.R. Grace vermiculite mine.
Why Is Asbestos Hazardous?
Asbestos is made up of microscopic fibers that can easily become airborne and inhaled. Because of their shape, the asbestos particles cling to tissues of the lungs and other areas of the respiratory system. The fibers are too durable for the immune system to break them down and remove them, and they cause scarring and inflammation over time that can eventually develop into tumors.
Asbestos can cause many health risks, including cancer and chronic respiratory illnesses. It can take 10 – 50 years from the time of exposure for conditions to develop, making them difficult to diagnose in early stages and often resulting in a poor prognosis.
- Mesothelioma: This aggressive cancer forms in the thin membrane (mesothelium) that protects vital organs in the chest and abdomen. Exposure to asbestos is the only medically-verified cause of the disease.
- Lung Cancer: Most commonly associated with factors like smoking and radon, lung cancer is also known to be exacerbated by exposure to asbestos. Researchers have found that about 3 – 4% of lung cancer diagnoses are asbestos related.
- Asbestosis: This degenerative respiratory condition results from the formation of scar tissue plaques on the surface of the pleura lung tissue (lung linings). It can be a precursor to the onset of mesothelioma.
According to the EPA, there is no safe level of asbestos exposure. Despite this fact, asbestos is not yet banned in the U.S., and may still be present in old buildings, homes and household items. Millions of people have been exposed to asbestos due to its extensive use, with researchers estimating that at least 20 million people are at risk of developing mesothelioma at some point in their lives.
Who Is at Risk of Exposure to Asbestos?
Though anyone can potentially face asbestos exposure because of the mineral’s heavy past use, there are numerous occupations that face a higher risk of exposure. Asbestos was used in thousands of commercial products and in industrial capacities, including shipbuilding, commercial product manufacturing, power plants and construction. Because of its extensive use, millions of workers face exposure every year.
Veterans in all five branches of the military face a high risk for asbestos exposure, as well. The mineral was used heavily in Navy ships, aircraft and military vehicles, sleeping barracks, training facilities and more. As a result, veterans are among the most at risk for developing mesothelioma, accounting for about one-third of diagnoses.
Workers’ and veterans’ families are also at risk of secondary exposure. Workers exposed to asbestos on the job may unknowingly transport fibers on their clothes or equipment, potentially exposing loved ones who come into contact with them. Though more rare than workplace exposure, researchers estimate about 20% of mesothelioma cases are a result of secondhand exposure.
Where Asbestos Can Be Found
There are many sites, both commercial and residential, where asbestos is still used in various ways or past uses of the mineral may remain and present risk of exposure. In addition to the mineral’s wide use in many industries, asbestos was also commonly used in building materials, insulation and electrical products in homes built before 1980. Although it can be difficult to tell whether a home has asbestos or not, older homes and buildings are more likely to contain asbestos products. There are several household items, such as hairdryers and crock pots, that may have used asbestos for its heat-resistant properties to prevent fires, as well. Though asbestos is no longer actively used in many of these products, any old goods lying around could be potentially dangerous.
Schools are also a high-risk environment for asbestos exposure, as most buildings built before 1980 contain asbestos. School buildings often contained asbestos in their vinyl ceiling tiles, sheetrock, panels, boilers and duct structures, which puts teachers, students and faculty at risk of exposure today.
Handling Asbestos and Safe Asbestos Removal
Asbestos that is contained and left undisturbed is normally considered safe. However, when it becomes agitated, broken or otherwise destroyed, asbestos fibers can become airborne and pose a danger to those who inhale or come in contact with it. Asbestos materials can become damaged from renovation or construction projects, storms or natural disasters and even just weathering due to old age. Because of this danger, individuals should not attempt to handle or remove asbestos on their own.
There are strict laws in place from the EPA, as well as the Occupational Safety and Health Administration (OSHA), that dictate how asbestos must be removed and disposed of to eliminate the risk of exposure for workers and the general public. Homeowners and building owners alike should always speak to an asbestos abatement professional prior to any construction or if they believe asbestos may be present somewhere. A licensed professional can take samples and recommend next steps, which can entail encapsulation of the mineral to prevent it from becoming airborne or removing it entirely.
Today, the dangers associated with asbestos are well-known and there are numerous alternatives to asbestos products currently on the market. Many of these alternative products are free of toxic substances and are “green,” providing a safe alternative for the environment and the individuals inside the building. Most are readily available and can be provided by a contractor.
- Amorphous Silica Fabrics: These fabrics are high-temperature materials used for a wide range of insulation and protection applications in industries such as aerospace, shipyards, molten metal and electric power generation. Generally not used for residential applications, the fabrics do contain fiberglass, which has come into question as a health hazard. However, in many industries these products have replaced similar products that once contained asbestos.
- Cellulose Fiber: One of the most popular alternatives to asbestos, cellulose insulation is made from finely shredded newsprint and is deemed safer than asbestos insulation. It is chemically treated to increase fire resistance and reduce mold in commercial and residential buildings. US GreenFiber, a company that manufactures cellulose insulation and other natural products, notes that about 15% of all new green buildings constructed in the U.S. choose this alternative.
- Flour Fillers: Some companies sell crack and crevice fillers and extenders made of natural materials that aid in insulation. These might include pecan shell flour, rice hull ash, rice flour and wheat flour. Because these are natural, they are a "green" option, presenting no hazards to those who are exposed to them.
- Polyurethane Foams: Spray polyurethane foams can be used in any type of structure and are extremely safe in that they emit no harmful gases. Manufacturers of these alternative products claim that their use reduces energy costs by about 30 – 35% annually.
- Thermoset Plastic Flour: Thermoset plastics can be filled with wood flour and other low-priced fillers to reduce cost and provide a balance of good insulation and strength. The building and construction industry is one of the largest users of plastics in the world and have called upon products such as this for heat, cold and sound insulation for both energy saving and noise reduction purposes.
Although there are many alternatives to asbestos that are being integrated into construction and insulating materials, asbestos is not yet banned in the United States and is still used in some instances. Many people are still at risk of asbestos exposure in homes, jobsites and other locations. Individuals should be mindful of where asbestos is found and understand their risk of developing mesothelioma and other related lung diseases as a result of exposure.
Author: Tara Strand
Senior Content WriterRead about Tara
Reviewer: Jennifer R. Lucarelli
Lawyer for Mesothelioma Victims and Their FamiliesRead about Jennifer