Toxizität von Methyl-tert-butylether auf innere Organe von Versuchstieren unter Kältebedingungen

Abstract

Background. The use of methyl tert-butyl ether (MTBE) is frequent. It can produce pollution of the environment and is a stress factor with potential health risks in workplaces. The simultaneous combined influence of a chemical and a physical stressor (MTBE and cold) can amplify the effects of MTBE. Workplaces with cold conditions are used in factories (e.g. chemical or construction industry). The aim of the work was the histological examination of the internal organs of rats under conditions of thermal comfort and in the cold. Material and methods. This toxicological study was carried out on 4 groups of 6 male rats. The 2 test groups were given 30 times MTBE in the stomach at a dose of 1/10 LD50 (500mg/kg of animal weight). The two control groups received distilled water. The groups were exposed to thermal comfort temperatures (25± 2 °C) or cold (4± 2 °C) for 4 h. Tissue samples were taken and histological examinations were made on day 30. Results. The pathological changes were significantly increased under exposure to cold conditions. Inflammatory reactions (e.g. glomerulonephritis), pulmonary emphysema and cytolytic signs of hepatocytes were found in the organs. The thyroid gland was hypothyroid. Reactive hyperplasia was detectable in the spleen. The adrenal border zones were barely definable and indicated a decreased functional activity of the nuclei of endocrine cells. Discussion. The histological studies showed a pronounced toxic potential of MTBE, which was significantly enhanced by cold conditions. Transferability to humans seems possible because MTBE in humans undergoes a similar degradation process as in rats. Therefore, special attention should be paid to protective measures at the workplace.