SCANNING ELECTRON-MICROSCOPIC EVALUATION OF THE ALTERATIONS INDUCED BY POLLUTED AIR IN THE RABBIT BRONCHIAL EPITHELIUM

With the aim of evaluating the influence of polluted air on the respir atory epithelium, ten New Zealand white rabbits, from a group of fifte en kept in the country, were transported to a site located in a metrop olitan area. After 40 days, all the rabbits were killed, and the bronc hial mucosa studied by scanning electron microscopy (SEM). In the anim als exposed to polluted air, the ciliated cells, less numerous than in normal cases, show an evident decrease in the number and size of the cilia, exposing apical microvilli. It is therefore possible to hypothe size that a part of the non-ciliated cells is made up of cells that ha ve lost their cilia. The number of non-ciliated elements and the amoun t of mucous secretion appear to have noticeably increased. The conside rable response of the respiratory epithelium to inhaled agents appears to be confirmed, as is the irritant effect of polluted city air.