Chemical characteristics of asbestos and associated trace elements.
Authors
Morgan-A; Cralley-LJ
Source
Biological effects of asbestos. Bogovski P, Gilson JC, Timbrell V, Wagner JC, eds. Lyon, France: International Agency for Research on Cancer, IARC Scientific Publication No. 8 1973; :113-118
Abstract
Chemical characteristics of asbestos (1332214) and its associated trace elements are reviewed. Asbestiform minerals can be classified as serpentine or amphibole according to their crystal structure. Chrysotile (12001295) is the sole commercial representative of the serpentine class and accounts for over 90 percent of asbestos produced. The five amphibole varieties used commercially are amosite (12172735), anthophyllite (16829439), crocidolite (12001284), actinolite (12172677), and tremolite (14567738). The minerals most commonly found in association with chrysotile include actinolite, antigorite (12135863), awaruite (12413819), chlorite (1318598), chromite (1308312), magnesite (13717005), nemalite (1317437), and talc (14807966). Neutron activation analysis (NAA) can be used to measure concentrations of chromium (7440473), cobalt (7440484), iron (7439896), manganese (7439965), and scandium (7440202) in asbestos samples; nickel (7440020) can also be determined by atomic absorption spectrophotometry (AAS). NAA is more sensitive than AAS for evaluating the concentrations of the majority of elements. Emission spectrography may also be used for the analysis of the same range of chemicals; the accuracy of this method is inferior to that achieved with either AAS or NAA. Acids attack chrysotile by reacting with the hydroxyl groups on the surface of the fibrils. Intrinsic differences in solubility are attributed mainly to variations in the porosity of fiber bundles. Evidence suggests that chrysotile magnesium dissolves readily in- vivo. The concentrations of chromium, nickel, and cobalt in amosite and crocidolite is about 1 or 2 orders of magnitude lower than in chrysotile. The amphiboles are much more resistant to attack by acids than is chrysotile. The authors conclude that magnesium removal may have an effect on the cytotoxicity and carcinogenicity of chrysotile.
Keywords
Air-contamination; Physiological-function; Asbestos-workers; Asbestos-fibers; Physiological-disorders; Air-sampling; Asbestosis; Biological-factors; Asbestos-dusts
CAS No.
1332-21-4; 12001-29-5; 12172-73-5; 16829-43-9; 12001-28-4; 12172-67-7; 14567-73-8; 12135-86-3; 12413-81-9; 1318-59-8; 1308-31-2; 13717-00-5; 1317-43-7; 14807-96-6; 7440-47-3; 7440-48-4; 7439-89-6; 7439-96-5; 7440-20-2; 7440-02-0
Editors
Bogovski-P; Gilson-JC; Timbrell-V; Wagner-JC
Source Name
Biological effects of asbestos, IARC Scientific Publication No. 8
