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Asbestos, a naturally occurring fi brous mineral, is widespread in nature. Asbestos is noncombustible, resistant to heat, and features a low conductivity and is insoluble in water. Asbestos is classifi ed 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 fi bers can be very small—up to 700 times smaller than a human hair. Because it is fi re resistant, resists many chemicals, and is an excellent insulator, asbestos was added to a variety of building materials and other products. The most important deposits are to be found in the former Soviet Union, Canada, and South Africa. Natural emissions are produced, for example, by the weathering of serpentine rocks.
Asbestos is not a chemical element, but rather an umbrella term for two groups of minerals, namely, serpentine and amphibole asbestos. Asbestos is a fi brous, impure mineral and its color varies between pure white and green, brown or gray, depending on the iron-oxide content. Crocidolite is blue or blue asbestos with fi bers between 20 and 25 nm long that are smooth and greasy to the touch. Asbestos, because of its heat resistance, suppleness, and its capacity for being incorporated into inorganic and organic binders, is used in industry for thermal insulation, fi reproofi ng, and sealing, in addition to acting as a fi ller in the production of countless composites (more than 3000). Economic exploitation is centered on chrysotile asbestos from the serpentine group (95%). Five percent of amphibole asbestos is used for asbestos fi ber production.
Spun asbestos is used for fi reproof, chemical-resistant clothing. When mixed with cement, asbestos is cast to form panels and pipes (70%–90% of the world’s production is used in the construction industry in Western Europe; acc. WHO, 1987). Asbestos has also been used as a fi lter material in the drinks and pharmaceutical industry and for the manufacture of brake and clutch linings for motor vehicles.

white, cream, brown or blue fibrous material;

Any of a group of impure magnesium silicate minerals that occur as slender, strong, flexible fibers. Colors range from white to gray, green, brown. Resistant to fire and most solvents. Breathing of ASBESTOS dust causes ASBESTOSis and lung cancer. Used as a heat resistant material, in cement, furnace bricks, and in brake linings.

Insoluble in water.

ASBESTOS minerals are generally unreactive.

Some may burn but none ignite readily. Containers may explode when heated. Some may be transported hot.

Various asbestos-induced illnesses are known from the industrial-medicine sector in which the size of the fi bers plays a crucial role. Generally speaking, fi bers with a diameter of <2 m and a length of >5 μm are considered to be hazardous to health (diameter:length = 1:3). Such a fi ber size is capable of entering the lungs, accumulating and becoming encapsulated. Fibers have also been found to have a certain migration capability in the organism and the cell metabolism. Accumulation in the lungs causes sclerosis of the pulmonary alveoli, thereby impairing oxygen exchange. The inhalation of large quantities of fi ber can cause asbestosis, which increases the risk of bronchial cancer. In particular, dusts <200 μm are highly toxic and are suspected of being a direct cause of tumors. Exposure to asbestos irritates the eyes and the respiratory tract. Direct penetration into damaged skin produces excessive hornifi cation. Fibers in the lungs cause chronic bronchitis, irritation of the pleura and pleurisy. Distension of the lungs can result in lung cancer. Workplace exposure may produce periods of latency in the gastrointestinal tract lasting up to 40 years. To date, there are no known characteristic toxicology data (DVGW, 1988).
Asbestos fi bers are released into the environment by natural and anthropogenic processes. The liberation of asbestos during the manufacture and processing of materials containing asbestos must be signifi cantly reduced, especially in confi ned areas and at workplaces because of the great hazard to the respiratory organs, in particular the lungs. There is increasing speculation that the oral intake of asbestos can cause tumors. Therefore, there is no justifi cation for the further use of asbestos cement in drinking water pipes. Numerous products containing substitute materials are now making it possible to dispense with the use of substances containing asbestos.

Most asbestos is used in the construction industry. Much of it is firmly bonded, i.e., the asbestos is “locked in” in such products as floor tiles, asbestos cements, and roofing felts, and shingles; while the remaining 8% is friable or in powder forms present in insulation materials, asbestos cement powders, and acoustical products. As expected, these latter materials generate more airborne fibers than the firmly bonded products. The asbestos used in nonconstruction industries is utilized in such products as textiles; friction material including brake linings and clutch facings; paper, paints, plastics, roof coatings; floor tiles, and miscellaneous other products. Significant quantities of asbestos fibers appear in rivers and streams draining from areas where asbestos-rock outcroppings are found. Some of these outcroppings are being mined. Asbestos fibers have been found in a number of drinking water supplies, but the health implications of ingesting asbestos are not fully documented. Emissions of asbestos fibers into water and air are known to result from mining and processing of some minerals. Exposure to asbestos fibers may occur throughout urban environments perhaps resulting from asbestos from brake linings and the flaking of sprayed asbestos insulation material. In recent years, much effort has been put into removal of asbestos insulation, particularly from schools and other public buildings where worn or exposed asbestos causes public exposure. Incompatibilities: None

If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 15 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water.

UN2212 Blue asbestos (Crocidolite) or Brown asbestos (amosite, mysorite), Hazard class: 9; Labels: 9-Miscellaneous hazardous material. UN2590 White asbestos (chrysotile, actinolite, anthophyllite, tremolite), Hazard class: 9; Labels: 9-Miscellaneous hazardous material.

Asbestos is a fibrous silicate of magnesium and calcium. However, the “extender”, known as “asbestine”, that has come to the forefront in paint making, is really a ring silicate of magnesia and slightly alkaline, but without the fibrous texture of asbestos or amianth. Asbestine pulp (as a certain variety of the material mined at the foot of the Adirondack mountains is known to the trade), although it is sold in the dry powdered form, belongs really to the soapstone or talc variety. But it is not as unctuous as either of those, has a harder texture, and is of whiter color than either soapstone or talc.

Asbestos may be recovered from waste asbestos slurries as an alternative to disposal. Landfilling is an option for disposal if carefully controlled.

White or greenish (chrysotile), Blue (crocidolite), or gray-green (amosite) fibrous, odorless solids; freezing/ melting point5600 C (Decomposes). Hazard identification (based on NFPA-704 M Rating System): Health 2; flammability 0; reactivity 0. Insoluble in water. Asbestos is a generic term that applies to a number of naturally occurring, hydrated mineral silicates incombustible in air and separable into filaments. The most widely used in industry in the United States is chrysotile, a fibrous form of serpentine. Other types include amosite, crocidolite, tremolite, anthophyllite, and actinolite.

Inhalation of dust or fine particles is dangerous. Carcinogenic.

Any of six naturally occurring minerals characterizedby being extremely fibrous (asbestiform),strong, and incombustible. They areutilized in commerce for fire protection; asreinforcing material for tiles, plastics, andcements; for friction materials; and for thousandsof other uses. Because of a great concernover the health effects of asbestos, many countries have promulgated strict regulationsfor its use. The six minerals designated asasbestos also occur in a nonfibrous form. Inaddition, there are many other minerals thatmorphologically mimic asbestos because oftheir fibrous nature.
The important characteristics of the asbestosminerals that make them unique are theirfibrous form; high strength and surface area;resistance to heat, acids, moisture, and weathering;and good bonding characteristics withmost binders such as resins and cement.
Asbestos is used for many types of products because of its chemical and thermal stability, high tensile strength, flexibility, low electrical conductivity, and large surface area. Past uses of asbestos, such as sprayed-on insulation, where the fibers may become easily airborne, have been generally abandoned. Asbestos is used predominantly for the construction industry in the form of cement sheets, coatings, pipes, and roofing products. Additional important uses are for reinforcing plastics and tiles, for friction materials, and packings and gaskets.

Asbestos and all commercial forms of asbestos are known to be human carcinogens based on sufficient evidence of carcinogenicity from studies in humans.

Color Code—Blue: Health Hazard/Poison: Store ina secure poison location. Prior to working with asbestosworkers must be, by law, trained in its proper handling andstorage. Asbestos should be stored wet with special surfactants and water. Keep asbestos in closed, impermeable,sealed containers. Protect against physical damage. A regulated, marked area should be established where this chemicalis handled, used, or stored in compliance with OSHAStandard 1910.1045.

None.