Study on pulmonary cell toxicity and pathology in rats exposed to air pollutants

  Objective   To explore pulmonary cell toxicity and patho logical change in rats exposed to air pollutants.

  Methods   80 Wistar rats(180-220g weight)were randomly divided into 4 groups, which were control group and treat ed groups (low, middle and high dose groups).Treated rats were respectively exposed to TSP of 7.5, 15 or 30 mg in 0.85% NaCl of 1ml by intratracheal instillation, and then were exposed to SO₂, NO₂ of 8, 5;16, 10 or 32, 20 mg/m³ by stat ically for 7 days.0.85% NaCl of 1ml was instilled and general air was inhaled by rats of control group.The counts of WBC and Eos as well as the sorts of WBC in BALF were measured.The changes of ultramicroscopic structure in lungs were observed under electron microscope.

  Results   The count of WBC in high dose group was significantly higher than that in control group(P < 0.05).The thickness of alveoli wall was increased with increased dose.There was hyperplasia of connective tissue in pulmonary interstitial.Non-smooth in alveoli wall and combined alveoli were observed.

  Conclusion   Air pollutants could induce acute inflammation in lungs and decrease respiratory area.And early fibrosis may occur.