Asbestos is the generic term for a group of naturally occurring highly toxic fibrous silicate minerals with high tensile strength, flexibility, and resistance to thermal, chemical, and electrical conditions.
Chemically, asbestos minerals contain silicon and oxygen atoms in their molecular structure. Asbestos is also resistant to heat and corrosion.
Asbestos fibers are 5 micrometers or longer with a length-to-diameter ratio of at least 3 to 1.
Asbestos includes the mineral fibers chrysotile, amosite, crocidolite, tremolite, anthophyllite, actinolite and any asbestos-containing material (ACM) or presumed asbestos-containing material (PACM) that have been chemically treated or altered.
Asbestos may also be “friable” or “non-friable”:
According to the Environmental Protection Agency (EPA), there are two major categories of asbestos:
When handled, asbestos can separate into microscopic-size particles that remain in the air and are easily inhaled. Persons occupationally exposed to asbestos have developed several types of life-threatening diseases, including asbestosis, lung cancer and mesothelioma. Although the use of asbestos and asbestos products has dramatically decreased in recent years, they are still found in many residential and commercial settings and continue to pose a health risk to workers and others.
Asbestos has been used since the late 1800s in commercial applications and the use increased greatly throughout World War II. Asbestos was used in military ships, vehicles and aircraft until the 1970s and many thousands of those who served in the military were exposed.
Before experts knew that the inhalation of asbestos fibers caused several deadly diseases- including asbestosis, a progressive and often fatal lung disease, and lung and other cancers- asbestos was used in a large number of building materials and other products because of its strength, flame resistance, and insulating properties. Asbestos was used in asbestos-cement pipe and sheeting, floor and roofing felts, dry wall, floor tiles, spray on ceiling coatings, and packing materials.
Always presume building materials may contain asbestos. The U.S. has not banned asbestos entirely in all its forms, so employers must take caution when buildings, especially those built before 1980, are renovated or torn down. A commercial building or residence may still contain asbestos. Remember, when the asbestos-containing materials themselves are disturbed, fibers may be released into the air. The fibers are so small that workers cannot see it with the naked eye. The fact you can inhale these fibers without knowing it makes asbestos an even more dangerous hazard.
Because asbestos is strong and resistant to heat, it has been used in many different types of products. In the construction industry, asbestos is used in more than 3,000 building products.
Some materials are presumed to contain asbestos if installed before 1981. For example, vinyl asbestos floor tiles may be as much as 15% to 20% asbestos, which is released when old flooring is removed.
Examples of products that may contain asbestos-containing materials (ACM) or presumed asbestos-containing materials (PACM) include:
Check out this comprehensive list of asbestos-containing-products.
Asbestos is not a serious health problem unless the fibers are disturbed and released into the air. The fibers are so small that workers cannot see it with the naked eye. The fact you can inhale these fibers without knowing it makes asbestos an even more dangerous hazard. Significant exposure to asbestos can cause breathing problems, lung cancer, and cancer of the lung lining many years after exposure. Therefore, only specially trained asbestos workers may remove asbestos.
Here’s some interesting information and highlights why asbestos in the U.S. is considered the Silent Killer:
Exposure to asbestos increases your risk of developing lung disease as fibers become embedded and accumulate in lung tissue over time. There is no known safe level of exposure to asbestos, so contact with any amount of asbestos should be avoided. Disease symptoms may take several years to develop following exposure.
Asbestosis is a serious, progressive, long-term non-cancer disease of the lungs. It is caused by inhaling asbestos fibers that lodge in the alveoli and cause the tissues to scar. The scarring makes it hard for oxygen to get into the blood.
Symptoms of asbestosis include shortness of breath and a dry, crackling sound in the lungs while inhaling. There is no effective treatment for asbestosis.
Lung cancer causes the largest number of deaths in the U.S. related to asbestos exposure. People who work in the mining, milling, manufacturing of asbestos, and those who use asbestos and its products are more likely to develop lung cancer than the general population.
The most common symptoms of lung cancer are coughing and a change in breathing. Other symptoms include shortness of breath, persistent chest pains, hoarseness, and anemia.
Epidemiologic evidence has increasingly shown that all asbestos fiber types, including the most commonly used form of asbestos, chrysotile, causes mesothelioma in humans.
Mesothelioma is a rare form of cancer due to asbestos fibers lodging in the thin lining of the lungs causing tumors to grow in the lung, chest, abdomen, and heart. This disease may not show up until many years after asbestos exposure.
It is important to know the following things about exposure to asbestos:
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