Toxic Metals in Hens' Eggs in India: A Preliminary Report

Lung function, biochemistry, and histology were examined in 34 silicotic and 29 control rats. Silicosis was produced by intratracheal injection of 50 mg of quartz dust. Pulmonary function tests four months after dusting showed the following changes in the silicotic rats: increases in frequency of breathing, functional residual lung capacity, lung resistance, work of breathing, oxygen consumption, and carbon dioxide tension of aortic blood; and decreased lung compliance and oxygen tension of aortic blood. Biochemical studies revealed a more than fivefold increase in wet weight of silicotic lungs and an eightfold increase in total amount of hydroxy-proline. Histologically, there were many fibrotic nodules present with emphysema in the remaining portions of the silicotic lungs. Correlation of morphological, biochemical, and functional changes and the importance of the animal-model experiments to functional examination are discussed.