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1.
Am J Ind Med ; 32(6): 592-4, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9358914

RESUMO

Major and trace element compositions for chrysotile (2 samples), amosite, crocidolite, and anthophyllite UICC standard asbestos samples have been determined using UV-visible spectrophotometry, atomic absorption spectometry, flame photometry, volumetric analysis, and gravimetric analysis for major elements and x-ray and optical spectrometry for trace elements. The trace element data are for Li, S, Cl, Sc, V, Cr, Co, Ni, Cu, Zn, Ga, Rb, Sr, Zr, Nb, Ba, La, Ce, Pb, and Th and distribution in the various mineral phases is discussed.


Assuntos
Amianto/química , Oligoelementos/análise , Amianto Amosita/química , Asbesto Crocidolita/química , Asbestos Serpentinas/química , Humanos , Espectrofotometria Ultravioleta
2.
J Toxicol Environ Health ; 2(2): 255-84, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1011287

RESUMO

Representative consumer talcums and powders, including 20 body powders, baby powders, facial talcums, and also one pharmaceutical talc, were analyzed to determine their mineralogical and chemical composition. Where known, all were formulated prior to 1973. Of the 20 products 10 contained detectable amounts of tremolite and anthophyllite, principally asbestiform, while some also contained fragmented forms of these minerals. The amounts ranged from tenths of a percent to over 14% by weight; two contained detectable amounts of chrysotile asbestos fiber. Eight contained quartz, seven ranging from 2 to 5%, with one as high as 35%. The analyses showed that the consumer products examined were rarely the pure mineral talc, but rather were mixtures of various minerals; some samples consisted of three to five minerals, only one of which was talc. Other common mineral phases included chlorite, platy serpentine, pyrophyllitem mica, and carbonate minerals. Kaolin additive was identified in two products. The single pharmaceutical talc examined contained only a trace amount of quartz. The chemical composition of these products, including both major oxide and trace element content, correlated with their mineral components. Four samples contained substantial concentrations of nickel, cobalt, and chromium, suggesting latice substitution or the presence of trace mineral phases. Geological provenance of the talcs may be ascertained on the basis of chemistry. Possible adverse health effects from intermittent use of these products, especially those that contain asbestiform and fragmented anthophyllite and tremolite, chrysotile, quartz, and trace metals, are presently unknown and warrnat evaluation.


Assuntos
Minerais/análise , Talco/análise , Amianto/análise , Cosméticos/análise , Indústrias , Microscopia , Microscopia Eletrônica , Óxidos/análise , Quartzo/análise , Difração de Raios X
3.
Environ Health Perspect ; 9: 125-7, 1974 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4470923

RESUMO

Variation in the precise conditions of geological formation may produce variations in the exact composition of asbestos minerals of a particular class, and thus in their biological interactions. Examples are given of differences in O(18)/O(16) ratios, TiO(2) content, lattice substitutions, substitution of Al (III) for Si (IV) and attachments to spare hydrostatic charges.


Assuntos
Amianto/análise , Alumínio/análise , Modelos Químicos , Tamanho da Partícula , Silício/análise , Propriedades de Superfície
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