BIOLOGICAL EFFECTS OF CONTAMINATED SILICON-CARBIDE PARTICLES FROM A WORKSTATION IN A PLANT PRODUCING ABRASIVES

A sample of silicon carbide dust taken in the field from a plant produ cing abrasives was studied in vitro. The SiC particles (part unmilled and part milled) were able to disturb the structure of erythrocyte mem branes and to lead to blood red-cell lysis; they also either interfere d with complement and activated the alternate pathway, or interacted w ith biological media and polymorphonuclear leucocyte membranes, thus e liciting reactive oxygen species production. These in vitro properties were detected both in original large particles and unmilled particles , over 40% of which were of respirable size. The ability of these SiC particles to produce complement activation in vitro lends support to t he previous hypothesis, that the radiographic opacities found in two w orkers employed in the same area of the plant from which the dust test ed was taken are due to a reaction by pulmonary interstitial structure s to SiC particle inhalation. It is speculated that SiC particles coul d act like asbestos, the ability of which to activate complement throu gh the alternate pathway is considered to be one of the mechanisms by which the initial asbestotic lesions and subsequent fibrotic inflammat ory infiltrates are generated in the lung. (C) 1997 Elsevier Science L td.