[Pathomorphological picture of various internal organs of rats after long-term exposure to toxic substances in raw coke gas].

The authors carried out morphological evaluation of a long-term action of toxic substances at low concentrations (about 1 NDS), contained in raw coke oven gas, i.e. gases: CO, H2S, SO2, NH3 and benzene, as well as dusts containing: C, SiO2, Pb and Cd on the liver and kidneys of three-month old male rats of the Wistar strain. The animals were exposed to the above toxic substances in an experimental chamber for 24 hr, and for 8 hr every day during 12 and 18 months. It was found that pathogenic action of the substances contained in raw coke oven gas was not the total action of all chemical components, but their complicated resultant. Significant differences in the intensity of morphological changes in lungs were observed between rats exposed for 8 hr ans 24 hr/day, in favour of the former. Such a relationship was not observed between 12 and 18 month exposition. Besides the catarrh of the air passages and cellular-fibrous changes in pulmonary alveoli, focal metaplasia of cells of bronchial epithelium was observed, which suggested the possibility of carcinogenic action of coke oven gases and dusts. No distinct morphological differences were found in the liver and kidneys between 8 and 24 hr exposition, whereas great differences were found between 12 and 18 months exposition. Chronic interstitial pyelitis was observed in kidneys after 18 month exposition.