Pulmonary Fibrosis from Amorphous Silica Dust, A Product of Silica Vapor

Abstract

After prolonged occupation exposure to amorphous silica dust-a product of vaporized crystalline silica (quartz)-eleven out of forty workers showed reticular and/or nodular abnormalities in roentgenograms of the chest. From this group, we present three illustrative cases. These had widespread pulmonary disease with granulomatous nodules and fibrosis (documented histologically in two cases), but there was no demonstrable restrictive impairment of pulmonary function. We discuss the possible importance of this previously underestimated toxicity, especially in an industrial setting.

Diffuse Interstitial Fibrosis in Nonasbestos Pneumoconiosis – A Pathological Study

“…Considering that the right lung is more frequently involved by pneumoconiosis [9], it is likely that DIF represents a dust-related disorder. There are reports in the literature, documenting cases of DIF associated with a burden of various metals [10][11][12][13][14], nonasbestos particulate matters [15,16] or amorphous sil ica [17,18], On the other hand, a possible pathogenetic link with idiopathic pulmonary fibrosis or cryptogenic fibros ing alveolitis may also be suggested [19][20][21]. 124 H onma/Chiyotani Pneum oconiotic Diffuse Interstitial Fibrosis Our data demonstrate that DIF tends to develop more frequently in elderly subjects with longer occupational his tories.…”

Mortality from nonmalignant respiratory diseases among male workers in Norwegian ferroalloy plants

“…According to available exposure information, amorphous silica seems to be the quantitatively dominating type of dust in furnace smoke, and, with respect to results from both human (11)(12)(13)(14)(15)(16)28) and aniinal (31) studies, amorphous silica exposure may be associated with the increased mortality from bronchitis, emphysema and asthma observed for the FeSiISi-met furnace workers. However, this exposure factor may be cosselated with other unknown exposure factors in furnace smoke.…”

“…There is however little evidence that silicosis can be caused by exposure to alnorphous silica in these plants (10). But a few case reports exist of ferroalloy workers with a pulmonary disease referred to as ferroalloy workers' disease (1 [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. In most of these reports an association with exposure to amorphous silica has been suspected.…”

Was there sufficient justification for the 10-fold increase in the TLV for silica fume? A critical review

“…However, a number of publications have presented X-ray diffraction analysis of the silica fume emission, thus providing a relatively clear indication of the innate toxicity of the particular amorphous silica fume [Brambilla et al, 1980;Broch, 1949;Cherniack and Boiano, 1983;Corsi and Piazza, 1970;Klosterkötter, 1966;Perdrix et al, 1984;Pollicard and Collet, 1954;Pozzani et al, 1966;Princi et al, 1962;Prochazka, 1971;Renovanz, 1984;Robalo-Cordiero et al, 1983;Robock, 1968;Swensson, 1967;Taddei et al, 1979;Vitums et al, 1977]. Perhaps some concentration of crystalline silica should be considered to be an integral part of silica fume, emerging as it does from conversion of the fume itself, the proportion depending on the arbitrary temperature of the furnace.…”