THE CHAMBER EXPOSURE OF LABORATORY RATS TO METAL-OXIDES ORIGINATING FROM METAL PRODUCING INDUSTRY

Laboratory rats were exposed to the inhalation of dust from an agglome ration unit which is the greatest contributor to dust pollution in the vicinity of a mercury producing plant. The exposure lasted for 6 mont hs (4 hours daily, 5 days per week), the concentration of aerosol in t he chamber was 10 mg.m(-3). After finishing the exposure, the animals were examined and compared with the controls which were held under sta ndard laboratory conditions. The number of alveolar macrophages was hi ghly elevated (P < 0.001) in the exposed animals, Mg2+ ATPase activity in the heart muscle was decreased. The alanine aminotransferase activ ity in the serum was not changed, the aspartate aminotransferase was s lightly enhanced. No differences in the frequency of abnormal sperm an d in the frequency of polychromatic erythrocytes in bone marrow were d etected.