Objective   To explore the patheologic changes in trachea of rats exposed to air pollutants.

  Methods   80 Wistar rats(180~200 g weight)were rando mly divided into 4 groups, i.e.a control group and 3 treated groups(low, middle and high dose groups).Treated rats were respectively exposed to total suspended particulate(TSP)of 7 5, 15 or 30 mg in 0.85% NaCl 1 ml by intratracheal instillation, and then respectively inhaled mixed air of SO ₂, NO₂(8, 5mg/m³; 16, 10 mg/m³; 32, 20 mg/m³)by statically 2 h per day for 7 days.0.85% NaCl 1 ml was instilled and general air was inhaled in rats of contr ol group.The changes of ultramicroscopic structure in trachea were observed underelectron microscope.

  Results   The adhesion, distur bance, lodge, and squamous metaplasia of cilia in tracheal epithelium; and vacuolar degeneration in epithelium cells were observed.And the neonate ciliate epithelium was also observed.

  Conclusion   Air pollutants may induce the decrease and loss of swing function, and the obstruction of discharg ing function of cilia in tracheal of rats.