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List of Chemical Substances
Published in T.S.S. Dikshith, and Safety, 2016
Asbestos, a naturally occurring fibrous mineral, is widespread in nature. Asbestos is non-combustible, resistant to heat, and features a low conductivity and is insoluble in water. Asbestos is classified into two groups: (i) serpentine and (ii) amphibole. The serpentine group includes: (i) chrysotile: molecular formula: Mg3Si2O5(OH)4; and (ii) crocidolite: molecular formula: Na2Fe2(Fe,Mg)3Si8O22(OH)2. The amphibole group includes (i) amosite: molecular formula: Na2Fe2(Fe,Mg)3Si8O22(OH)2; (ii) anthophyllite: molecular formula: Mg7Si8O22(OH)2; (iii) tremolite: molecular formula: Ca2Mg5Si8O22(OH)2; and (iv) actinolite: molecular formula: Ca2(Mg,Fe)5Si8O22(OH)2.
Asbestos Identification and Abatement
Published in Benjamin Alter, Environmental Consulting Fundamentals, 2019
There are six known asbestos minerals, as follows: Chrysotile, a white or greenish-colored mineral, was the most commonly used asbestiform in the United States and the only serpentine asbestiform (see Figure 15.1).Amosite, also known as “brown asbestos,” is an amphibole asbestiform that derives its name from the asbestos mines of South Africa.Crocidolite, also known as “blue asbestos,” is an amphibole asbestiform that was mainly mined in South Africa and Australia, and had limited usage in the United States.Anthophyllite is an amphibole asbestiform that has excellent resistance to chemicals and heat. It was primarily used in the United States in decorative and acoustical material.Tremolite is a white to yellow-colored amphibole asbestiform that has a major ingredient in industrial and commercial talc. There is also a non-asbestiform type of tremolite.Actinolite, an amphibole asbestiform that is greenish to white in color, has poor resistance to chemicals and had limited commercial usage. It may be found in commercial and industrial talcs.
Microporous and Mesoporous Solids
Published in Elaine A. Moore, Lesley E. Smart, Solid State Chemistry, 2020
Elaine A. Moore, Lesley E. Smart
In double chains alternate tetrahedra share two and three oxygen atoms, respectively, as in Figure 7.2d. This class of minerals are known as the amphiboles, usually containing magnesium and/or iron (Figure 7.3b), an example of which is tremolite (Ca2Mg5(OH)2(Si4O11)2). Most of the asbestos minerals fall into this class. The repeat unit is Si4O116−.
Analytical transmission electron microscopy of amosite asbestos from South Africa
Published in Archives of Environmental & Occupational Health, 2020
Amosite is a mineral name for grunerite asbestos derived from South African mines and is based on the acronym “Amosa” for the mining company “Asbestos Mines of South Africa.” The name “amosite” specifically refers to the South African grunerite asbestos, which is the only known commercial-grade grunerite asbestos in the world. Amosite is one of the five amphibole asbestos minerals regulated under occupational laws. The other four regulated amphibole minerals are tremolite, actinolite, crocidolite, and anthophyllite.1 The extreme hazard of exposure to amosite fibers has been established. A landmark study2 involved 230 men exposed to amosite dust during and prior to 1954, when the production was moved to Texas,3 in a group of former employees followed between 1960 and 1971.2 During this time, there were 105 deaths, while 46.4 were expected. Twenty-five lung cancers were diagnosed, while 2–3 were expected. Five deaths were from mesothelioma occurred during the period of observation, while virtually none would be expected; 14 deaths occurred due to asbestosis. There were no other known exposures to asbestos.2
Reducing the risk of particulate matter containing asbestos using a high-efficiency, low-differential pressure system
Published in Aerosol Science and Technology, 2018
Sung Ho Hwang, Jaehoon Roh, Chanjung Park, Jongcheol Kim, Byong Hyoek Lee, Wha Me Park
Asbestos are naturally occurring fibrous silicate minerals that include chrysotile (serpentine asbestos), actinolite, crocidolite, amosite, anthophyllite, and tremolite (amphibole asbestos). Asbestos used to be widely used in constructions for their various desirable physical properties, including low thermal conductivity, high electrical resistance, resistance to fire, chemicals, and microorganisms, and high sound absorption. However, asbestos cause severe health problems (Wagner et al. 1960; Hillerdal 1999). Although amosite and crocidolite are the most hazardous types of asbestos, all six types have been shown to be carcinogenic (Berman and Crump 2003). Mesothelioma, a rare form of cancer that develops from mesothelial cells, has been observed in people exposed to asbestos. Moreover, asbestosis, an inflammatory medical condition affecting parenchymal tissues of the lungs, is associated with asbestos inhalation.
Characterization of pulmonary responses in mice to asbestos/asbestiform fibers using gene expression profiles
Published in Journal of Toxicology and Environmental Health, Part A, 2018
Naveena Yanamala, Elena R. Kisin, Dmitriy W. Gutkin, Michael R. Shurin, Martin Harper, Anna A. Shvedova
Asbestos is a term for a set of commercially important naturally occurring fibrous silicate minerals. Crocidolite (asbestiform riebeckite), amosite (asbestiform cummingtonite-grunerite), actinolite-tremolite asbestos, and anthophyllite asbestos belong to the amphibole minerals, while chrysotile is a serpentine mineral (Wylie and Candela 2015). The term “asbestiform” corresponds to a mineralogical habit or form of a mineral in which single fibers (fibrils) occur in bundles that can be detached into finer fibers and display curvature (Lowers and Meeker 2002). Similar to main asbestos types described above, there are “other regulated asbestiform minerals” fibers such as durable asbestiform zeolite minerals (e.g., erionite). The term asbestos has been used in commerce and regulations, but is not recognized in geology as referring to species separate from non-asbestos analogs of these minerals (Lowers and Meeker 2002). These materials were widely used for textiles and in construction, as well as in industrial application, until the 1970’s in the USA (Williams, Phelka, and Paustenbach 2007). Although the use has declined, asbestos continues to be utilized for certain applications in the USA and elsewhere (Dodson 2016; LaDou et al. 2010). Known human diseases associated with exposure to asbestos/asbestiform fibers include asbestosis, bronchial adenocarcinoma, squamous cell carcinoma of the respiratory epithelium and large/small cell lung carcinoma and diffuse malignant mesothelioma (Andujar et al. 2016; Lemen 2016; Ndlovu et al. 2017).