History and Industrial Use of Asbestos
– Asbestos has been used for thousands of years to create fire-resistant objects.
– Large-scale mining and use of asbestos began in the late 19th century.
– Asbestos was commonly used as a building material until its health effects were widely acknowledged in the 1970s.
– Companies began producing consumer goods containing asbestos on an industrial scale.
– Asbestos mining continues in many developing countries, with Russia being the top producer.
– Asbestos production started in the Urals of the Russian Empire in the 1880s.
– The Italo-English Pure Asbestos Company was formed in Turin, Italy in 1876.
– South Africa began asbestos mining in 1893.
– The U.S. asbestos industry began in 1858 with fibrous anthophyllite mining.
– US production expanded in 1899 with the discovery of large deposits in Belvidere Mountain.
Health Effects of Asbestos
– Inhalation of asbestos fibers can lead to dangerous lung conditions, including mesothelioma, asbestosis, and lung cancer.
– The latency period for asbestos-related health effects is typically 20 years.
– At least 100,000 people are thought to die each year from diseases related to asbestos exposure.
– The most common diseases associated with chronic asbestos exposure are asbestosis and mesothelioma.
– Developing countries still support the use of asbestos as a building material despite its health risks.
Regulation and Awareness of Asbestos Dangers
– Asbestos use for construction and fireproofing is illegal in many countries, but mining continues.
– Asbestos use is completely banned in 66 countries and strictly regulated in many others.
– Asbestos is recognized as a health hazard.
– The use of asbestos for construction and fireproofing is strictly regulated.
– Australia phased out asbestos use from the 1970s and banned it entirely in 2003.
– The first asbestos industry regulations were published in 1931.
– Mesothelioma was first associated with asbestos in the 1940s.
– The US government and asbestos industry were criticized for concealing asbestos dangers.
Types and Applications of Asbestos
– Chrysotile (white asbestos) is the only asbestos mineral in the serpentine group.
– Chrysotile accounts for approximately 95% of asbestos found in buildings in the United States.
– Chrysotile is no longer used in the United States.
– Amphiboles including amosite (brown asbestos) and crocidolite (blue asbestos) were formerly used in many products.
– The use of all types of asbestos in the amphibole group was banned in much of the Western world by the mid-1980s.
– Asbestos was used in fire-retardant coatings, concrete, bricks, and pipes.
– It was used in heat-, fire-, and acid-resistant gaskets and pipe insulation.
– Asbestos was used in ceiling insulation, fireproof drywall, and flooring.
– It was used in roofing, lawn furniture, and drywall joint compound.
– Vermiculite is a hydrated laminar magnesium-aluminum-iron silicate that can be used for many industrial applications and as insulation.
– Some deposits of vermiculite are contaminated with small amounts of asbestos.
– Talc can sometimes be contaminated with asbestos due to the proximity of asbestos ore in talc deposits.
Asbestos Contamination and Cleanup
– Some older buildings may have asbestos-containing materials such as insulation, roofing, and flooring.
– Asbestos has been used in automotive parts, such as brake pads and clutch facings.
– Asbestos can be present in certain types of cement and pipes.
– Asbestos contamination can occur in soil and dust in areas where asbestos-containing products were used or disturbed.
– Inhalation of asbestos fibers can cause lung diseases, including asbestosis and lung cancer.
– The EPA has implemented regulations to control and minimize asbestos exposure.
– The EPA has designated certain areas as Superfund cleanup sites due to asbestos contamination.
– Cleanup efforts have been undertaken in locations such as Libby, Montana.
– Ongoing monitoring and enforcement of asbestos regulations are in place. Source: https://en.wikipedia.org/wiki/Asbestos
Asbestos (/æsˈbɛstəs, æzˈ-, -tɒs/ ass-BEST-əs, az-, -oss) is a naturally occurring fibrous silicate mineral. There are six types, all of which are composed of long and thin fibrous crystals, each fibre (particulate with length substantially greater than width) being composed of many microscopic "fibrils" that can be released into the atmosphere by abrasion and other processes. Inhalation of asbestos fibres can lead to various dangerous lung conditions, including mesothelioma, asbestosis, and lung cancer. As a result of these health effects, asbestos is considered a serious health and safety hazard.
| Asbestos | |
|---|---|
 | |
| General | |
| Category | Silicate minerals |
| Strunz classification | 09.ED.15 |
| Dana classification | 71.01.02d.03 |
| Crystal system | Orthorhombic, monoclinic |
| Identification | |
| Formula mass | 277.11 g |
| Color | Green, red, yellow, white, gray, blue |
| Crystal habit | Amorphous, granular, massive |
| Cleavage | Prismatic |
| Fracture | Fibrous |
| Mohs scalehardness | 2.5.6.0 |
| Luster | Silky |
| Streak | White |
| Specific gravity | 2.4–3.3 |
| Optical properties | Biaxial |
| Refractive index | 1.53–1.72 |
| Birefringence | 0.008 |
| 2V angle | 20° to 60° |
| Dispersion | Relatively weak |
| Extinction | Parallel or oblique |
| Ultraviolet fluorescence | Non-fluorescent |
| Melting point | 400 to 1,040 °C (752 to 1,904 °F) |
Archaeological studies have found evidence of asbestos being used as far back as the Stone Age to strengthen ceramic pots, but large-scale mining began at the end of the 19th century when manufacturers and builders began using asbestos for its desirable physical properties. Asbestos is an excellent thermal and electrical insulator, and is highly fire resistant, so for much of the 20th century, it was very commonly used across the world as a building material, until its adverse effects on human health were more widely acknowledged in the 1970s. Many buildings constructed before the 1980s contain asbestos.
The use of asbestos for construction and fireproofing has been made illegal in many countries. Despite this, at least 100,000 people are thought to die each year from diseases related to asbestos exposure. In part, this is because many older buildings still contain asbestos; in addition, the consequences of exposure can take decades to arise. The latency period (from exposure to the diagnosis of negative health effects) is typically 20 years. The most common diseases associated with chronic asbestos exposure are asbestosis (scarring of the lungs due to asbestos inhalation) and mesothelioma (a type of cancer).
Many developing countries still support the use of asbestos as a building material, and mining of asbestos is ongoing, with the top producer, Russia, having an estimated production of 790,000 tonnes in 2020.
