Toxic effects of trichloroethylene on the lung

ABSTRACT

This study aimed to investigate the effect of trichloroethylene on the lung ofalbino rats histopathologically and ultrastructurally. The experimentalanimals were divided into three treated groups. One group was administeredtrichloroethylene as a single dose [2000 mg/kg] intraperitoneally. The secondand third treated groups received trichloroethylene as repeated doses [1000mg/kg] intraperitoneally every other day for two and four weeks, respectively. Light microscopy of lungs of the first group exhibited variable degenerativechanges including lining epithelium of bronchioles. Electron microscopicexamination revealed a dilatation of endoplasmic reticulum, distension ofperinuclear cisternae and disorientation of mitochondria. Lung of the secondand third groups exhibited variable necrotic changes including bronchiolarepithelium and diffuse interstitial fibrosis in the alveolar zone resulting ina thickening of alveolar septa and distortion of lung structure. Electronmicroscopy revealed cellular changes similar to those in the first group, butof varying degrees. Additionally, there were parenchymal changes includingtype II alveolar cells, which had reduced the numbers of lamellar bodies anddistortion of the microvilli. These results demonstrated thattrichloroethylene is pneumotoxic and affects bronchiolar epithelial andalveolar type II cells