[Biological testing of fibrogenic effect of dust from the "Gliwice" mine on the lung tissue].

Animal study was carried out to determine biological aggressiveness of mining dust by means of pulmonary tests. Dust samples, 50 mg settled dust, a mixture from 3 different mine layers (sample A) and 50 mg dust collected by the gravimetric method from different mine layers (sample B) were administered in two respective test groups by a single intratracheal injection. Silica content, determined according to Polezhayev, was found to range from 4.6% (sample A) to 12.7% (sample B). In months 3 and 6 of the experiment lung content of hydroxyproline was determined following Stegemann. Biochemical tests for hydroxyproline content revealed highest increase in the lungs of Group 2 animals 6 months after the onset of the experiment (10.312 mg). Very similar result was obtained in Group 1, with injected settled dust mixture: hydroxyproline level amounted to 10.214 mg. Both sample A and sample B induced elevated level of lung hydroxyproline although silica content in dust sample differed considerably. The study revealed that the biological aggressiveness of settled dust was not proportionate to the content of pure silica. It is thought that increased fibrogenic potentials of the settled dust may have resulted from defected crystalline structure of silica due to the grinding of the mineral in a hand-mill.