Quantification of proliferative lesions in hamster lungs after chronic exposure to cadmium aerosols

The development of proliferative areas in the lungs of Syrian golden hamsters was studied after chronic inhalation of cadmium oxide, cadmium sulfide, cadmium chloride or cadmium sulfate. Lung tissue from randomly selected animals in each group was evaluated by morphometric histopathologic techniques. Estimation of the volumetric ratio of proliferative areas within the lungs of exposed animals showed significantly different extents of these lesions in dependence on the respective cadmium compound administered. The most severe changes were observed after inhalation of cadmium oxide and cadmium sulfide. Lesions were mainly found in the peribronchial region of the lung. Electron microscopic analysis of these proliferative areas revealed that they were composed of ciliated and Clara cells. From its histophatologic appearance this of lesion was qualitatively comparable in all hamsters which had been treated with the different cadmium compounds.