Man-made vitreous fibers

Manila maguey, 11 296 Manmade composites, 11 302 Man-made vitreous fibers (MMVF),... 

The possibility of lung problems due to inhalation of fine particles or flakes or fibers of fiberglass has often been raised. The extensive medical research so far reported has shown no consistent evidence of chronic health effects in workers who are exposed to man-made vitreous fibers. In some studies where massive doses of fine-diameter fibers were implanted into mice, cancer development in the pleura was noted. Also some animal studies involving injection of fibers into the trachae resulted in a minimal fibrosis. 

Bellmann B, Muhle H, Kamstrup 0, et al. 1994. Investigation on the durability of man-made vitreous fibers in rat lungs. Environ Health Perspect Suppl 102 185-189. 

Hesterberg TW, Miller WC, Musselman RP, et al. 1996. Biopersistence of man-made vitreous fibers and crocidolite asbestos in the rat lung following inhalation. Fundam Appl Toxicol 29 267-279. 

Johnson NF, Jaramillo RJ. 1997. p53, Cipl, and Gaddl53 expression following treatment of A549 cells with natural and man-made vitreous fibers. Environ Health Perspect Suppl 105 1143-1145. 

Musselman R, Miiller W, Bastes W, et al. 1994a. Biopersistence of crocidolite versus man-made vitreous fibers in rat lungs after brief exposures. In Mohr U, Dungworth DL, Mauderly JL, et al, ed. Toxic and carcinogenic effects of solid particles in the respiratory tract. Washington,DC ILSI Press, 451-454. 

Musselman RP, Miiller WC, Bastes W, et al. 1994b. Biopersistences of man-made vitreous fibers and crocidolite fibers in rat lungs following short-term exposures. Bnviron Health Perspect Suppl 102 139-143. 

Pelin K, Kivipensas P, Linnainmaa K. 1995b. Effects of asbestos and man-made vitreous fibers on cell division in cultured human mesothelial cells in comparison to rodent cells. Environ Mol Mutagen 25 118-125. 

Stam-Westerveld EB (1996) Man-made vitreous fiber glass fiber and rockwool dermatitis. In van der Valk GM, Maibach HI (eds) The irritant contact dermatitis syndrome. CRC Press, Boca Raton, pp 121-126... 

FIGURE 6.36 Fiber-blowing process used to make refractory ceramic fibers. [Man-Made Vitreous Fibers Nomenclature, Chemical and Physical Properties, Nomenclature Committee of TIMA Inc., p. 16 (NAIMA—North American Insulation Manufacturers Assoc.).]... 

Mineralogical analysis only provides a reflection of the particle burden retained in the sample at the time of sampling, and the effect of clearance should not be neglected. This may be especially relevant in cases with very old exposures or exposures to particles or elements having low biopersistence in the lung, such as chrysotile asbestos, cobalt or some man-made vitreous fibers. 

Man-made fibers ean be amorphous, polycrystalline, or ciystalline. The amorphous fibers inelude the man-made vitreous fibers typified by the insulation wools, which form the bulk of man-made inorganic fibers. Polycrystalline fibers include continuous carbon fibers used in composite material and specialty fibers such as Saffil. Crystalline man-made fibers include ceramic whiskers, such as silicon carbide and silicon nitride, which are used in reinforce metals and other composite materials. 

Table 4 Chemical Composition of Man-Made Vitreous Fibers in Weight Pereent...

Lees PSJ, Breysse PN, McArthur BR, Miller ME, Rooney BC, Robbins CA, Corn M. End user exposures to man-made vitreous fibers 1. Installation of residential insulation products. AppI Occup Environ Hyg 8 1993 1022 1030. 

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