Histopathological changes in the respiratory tract of mice exposed to ten families of airborne chemicals.

The objective of this experimental work was to identify and compare the histopathological changes induced in the respiratory tract of Swiss mice exposed to repeated inhalation (4, 9 or 14 days) at typical concentrations of RD50, 0.3 x RD50 and 3 x RD50 of airborne chemicals. These substances were selected from ten chemical families: aldehydes, organic acids, alcohols, ketones, ethers, aromatic hydrocarbons, halogenated aromatic hydrocarbons, inorganic bases, amines and isocyanates. These experiments showed that the lesion intensity observed in the nasal passages varied with exposure duration and type of airborne chemical, but did not depend on the concentration of the substance. Results did not allow us to establish a relationship between the histopathological changes and the type of chemical family. No injuries were observed in trachea and lungs.