[Dust and occupational diseases in brickyards]

Air dustiness and mineralogical composition of dust in 9 building ceramics plants producing red brick were tested. Also analysed were occupational diseases diagnosed in Poland during 1979-1980 in workers of this industry. Concentrations of total dust and respirable fraction at all workstations exceeded the present mandatory allowable values for dusts containing free crystalline silica. By X-ray diffraction, alpha-quartz and illite were found in raw materials (clays) and intermediate products (green brick). In burnt brick alpha-quartz and mullite were found. The content of free crystalline silica was: in clay--over 30%, in total dust--5.8-18.4%, in respirable fraction 3.7-6.1%. Analysis of occupational diseases diagnosed in Poland during 1979-1980 revealed not a single case of pneumoconiosis or any dust--induced respiratory tract disease in those producing red brick. Instead, two pneumoconiosis cases were found among workers of the plant producing thermallite firebrick of biologically aggressive siliceous earth from Piotrowice--as one of its component. Most frequently, workers of the building ceramics plant were afflicted with occupational dermatoses, mostly this relates to bricklayers exposed to cement mortar. Two cases of occupational dermatosis were those of workers exposed to ash.