Epithelium ammonia effects

Gaafar H.A., Tantawy A., Hamza M. and Shaaban M. (1998). The effect of ammonia on olfactory epithelium and vomeronasal organ neuroepithelium of rabbits a histological and histochemical study. J Otorhinolaryngol 60, 88-89. 

Repeated or continuous exposure over several days or weeks has been studied in several animal species. The details of those studies are also presented in Table 2-8. As in acute studies, the primary effects caused by exposure are irritation of the upper respiratory tract, eyes, and skin. The results of the study by Buckley et al. (1984) are supported by the work by Zissu (1995), who repeatedly exposed mice to various concentrations of ammonia 6 h/d for up to 14 d. The minimum concentration of ammonia causing histopathologic changes in respiratory epithelium was 711 ppm. No changes were seen in the olfactory epithelium, lung, or trachea at this concentration. 

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