Pulmonary response to agate dust in vivo and cytotoxic and haemolytic effects in vitro

The pulmonary response to agate dust in vivo was investigated and also its cytotoxic action on peritoneal macrophages and sheep erythrocytes in vitro. The results were compared with quartz dust as the known fibrogenic dust and emery dust (Corundum) was used as a control dust. Agate increased the wet and dry weight of lungs and induced increased collagen formation and a non-reversible fibrotic reaction in the lungs. The tissue response and lung changes were of milder intensity than seen in rats exposed to quartz. In vitro, the extent of dye-uptake and haemolysis yielded results similar to those of the in vivo studies. Release of lactic dehydrogenase into the culture medium was similar in both the agate and emery exposed cells but significantly less when compared with quartz treated cells.