The impact of ethanol and tobacco smoke on intranasal epithelium in the rat

Background: Investigations have shown the influence of ethanol and tobacco smoke on olfaction, epithelial metaplasia, and cancer formation in the head and neck. Analysis of ethanol and tobacco smoke-induced histopathological mucosal changes in the upper respiratory tract may provide important insight into the pathophysiology of secondary olfactory dysfunction. Methods: Three groups of laboratory rats were experimentally exposed to either ethanol, tobacco smoke, or both, with a control group having no such exposure. Results: Compared with controls, histopathological analysis of nasal mucosa in exposed rats revealed a decrease in the length of olfactory epithelium, especially in the rats exposed to both ethanol and tobacco smoke. Structural changes included loss of cilia and metaplasia. Conclusion: The histological changes noted in rats after ethanol and tobacco smoke exposure, if relevant to human physiology, could explain the decreased olfactory ability seen in patients who use these products.