Asbestos fibrous anthophyllite

In the 1987 Regulations, asbestos is defined as any of the following minerals crocidolite, amosite, chrysotile, fibrous anthophyllite, fibrous actinolite, fibrous tremolite and any mixture containing any of these. Before carrying out work on any substance suspected of being asbestos, a competent person must be called to advise on its possible... 

Results of a survey of asbestos fibers in consumer cosmetic talc powders from Italian and international markets using electron microscopy, electron diffraction, and energy dispersive x-ray analysis showed that asbestos was detected in 6 of 14 talc samples from the European Pharmacopeia (Paoletti et al. 1984). Chrysotile was identified in 3 samples, 2 samples contained tremolite asbestos and anthophyllite asbestos, and 1 sample contained chrysotile and tremolite asbestos. The authors noted that, in all talc powders analyzed, fibrous talc particles frequently were present that were morphologically similar to amphibole asbestos fibers. Counting fibers as particles with aspect ratio >3 1 and width < 3 m, the percentages of particles that were asbestos fibers ranged from <0.03% to 0.13% for 4 samples, and were 18% to 22% for the other 2 samples. Paoletti et al. (1984) noted that the European Pharmacopeia, at that time, had not established analytical quality control of asbestos contamination. 

Asbestos A term for naturally occurring fibrous miner-ais. Asbestos inciudes chrysotile, cummingtonite-gruner-ite asbestos (amosite), anthophyllite asbestos, tremolite asbestos, crocidoiite, actinolite asbestos and any of these minerals which have been chemically treated or altered. The precise chemicai formulation of each species varies with the location from which it was mined. Nominal compositions are listed ... 

Less common substances which fall within the legal definition of asbestos are fibrous actinolite, fibrous anthophyllite and fibrous tremolite (and any mixture containing any of the above). 

Over the past several decades six different silicate minerals have been mined as asbestos and processed for industrial and commercial applications. The most commonly encountered asbestos mineral today is chrysotile. The five other minerals are tremolite, actinolite, anthophyllite, grunerite, and rie-beckite. All five are members of the amphibole group of minerals, and each can occur as chunky, acicular, or equant crystals, as well as in fibrous form. When found as fine fibrous aggregates, in quantities appropriate for mining, they are usually distinguished as a special variety—for example, tremolite-asbestos. 

ASBESTOS. The tenn asbestos is a generic designation referring usually to six types of naturally occurring mineral fibers which are or have been commercially exploited, These fibers are extracted from certain varieties of hydrated alkaline silicate minerals comprising two families seipe.ntin.es and amphiboles. The serpentine group contains a single fibrous variety chrysotile five fibrous forms of amphiboles are known anthophyllite, amosite, crocidolite. tremolite, and actinolite... 

Asbestos is the name given to a group of six different fibrous minerals (amosite, chrysotile, crocidolite, and the fibrous varieties of tremolite, actinolite, and anthophyllite) that occur naturally in the environment. One of these, namely chrysotile, belongs to the serpentine family of minerals, while all of the others belong to the amphibole family. All forms of asbestos are hazardous, and all can cause cancer, but amphibole forms of asbestos are considered to be somewhat more... 

It is important to recognize that asbestos is not a single substance, but is the generic name for a family of six related poly silicate fibrous minerals of which one (chrysotile) belongs to the serpentine family and five (actinolite, amosite, anthophyllite, crocidolite, and tremolite) belong to the amphibole family. These minerals differ from each other in physical and chemical properties, and each mineral can exist in a wide range of fiber sizes. These differences between fiber type and, more importantly, fiber size (length and diameter) are believed to be important determinants of the health risks posed by asbestos. 

Asbestos is the term for the fibrous form of a number of naturally occurring crystalline silicate minerals, which have been exploited commercially and are still mined and processed in various countries such as South Africa, Canada, the Former Soviet Union and China. The three main types of asbestos that have been commercially produced are Chrysotile, Amosite and Crocidolite, which are commonly referred to as White, Brown and Blue asbestos respectively. Other rarer forms of asbestos include Tremolite, Anthophyllite and Actinolite, which may be found either individually or as contamination within the three main types. 

Mineralogy Asbestos is a name for a set of naturally fibrous silicate minerals. Asbestos minerals have been used because of their high tensile strength, high heat resistance, resistance to chemical attack, and ability to be woven into cloth (Dupres et al. 1984). These properties vary by asbestos fiber type. There are six accepted types of asbestos fibers namely, chrysotile, amosite, crocidolite, antho-phyllite, tremolite, and actinolite. These fibers can be separated into two broad mineralogical groups chrysotile or amphiboles, the latter including amosite, crocidolite, tremolite, actinolite, and anthophyllite. Table 2.1.6 lists the diseases caused by asbestos. While Table 2.1.6 is correct in broad outline, there are considerable discrepancies in the abil-... 

The asbestos minerals are crystalline fibrous silicates, some of which have been exploited commercially, especially as an insulating material. These minerals comprise sheets, or chains of silicate tetrahedra in which oxygen is either bound to two silicon atoms or to one silicon atom, and possesses a negative charge. There are two major groups of asbestos mineral serpentines and amphiboles. White asbestos or chrysotile is a serpentine mineral, whereas the other forms of asbestos, crocidolite (blue asbestos), amosite (brown asbestos), anthophyllite, tremolite, and aetinolite, are amphiboles. Tremolite can also be found as a contaminant in other minerals, such as chrysotile, talc, and vermiculite. 

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