Abstract: OBJECTIVE:To investigate changes of serum oxidative stress index in rats after their exposure to fire drill prop smoke. METHODS:40 rats were divided randomly into five groups:1 unexposed and 4 exposure groups with each group investigated at 1,6,24 and 168 h after the exposure. Exposures were carried out in a smoke producing device according to the GB/T 20285-2006 Classification of Smoke Toxicity Risk of Material. Blood samples were collected from femoral arteries to detect changes of GSH,MDA and SOD. Trachea and lung tissues were collected and stained by HE staining for histopathological examinations. RESULTS:After exposure,rats showed obvious injury symptoms in the nervous and respiratory systems. In addition,their weights were reduced,to a significant level for the 168 h group. Histopathological examination revealed significant inflammatory damage to the tracheas and lungs. Serum GSH concentrations of rats in the 6,24 and 168 h groups at 1.177,1.109 and 1.076 ng/mL,respectively,were significantly lower than those in the blank control group (P < 0.05 or P < 0.01). The serum MDA concentration in the 168 h group was 1.008 nmol/mL,which was significantly higher than that of the blank control group (P < 0.01). The serum SOD concentrations in the 24 and 168 h groups were 1.294 and 1.260 ng/mL,respectively,which were significantly lower than those in the blank control group (P < 0.05). CONCLUSION:Acute exposure to fire drill prop smoke can cause significant damage to the body. In addition,the oxidative stress index in serum changed obviously. Thus,oxidative stress reactions may be an important injury mechanism for excessive fire drill prop smoke exposure.

Key words: fire drill prop, smoke, oxidative stress, inhalation injury