[Effect of sulfuric acid vapors on the respiratory system]

The influence of a mixture of sulphuric acid vapour and SO2 mist upon the respiratory tract of animals was investigated during on exposure lasting 8 and 12 hours. Marked inflammatory changes in the upper respiratory tract, bronchioli and lung parenchyma were found. These changes were manifested by inflammatory infiltrations and abundant production of mucous in the bronchial tree. A significant increase in the number of dust cells in the lumen of bronchioli was also observed. A decrease of mitotic index was found in the epithelium of oral cavity after inhalator intoxication with sulphuric acid. This may lead to disturbances in the repair of epithelium. The authors emphasize the intensity of changes in proportion to H2SO4 dosage.