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[Effects of air pollution exposure on olfaction of rats in Beijing].

Objective: To evaluate the effects of exposure of fine particle matter (PM2.5) and ozone (O3) in Beijing as the main pollutants on olfaction of SD rats. Methods: In October 16, 2018, twenty 8-week-old SD rats were randomly divided into two groups, 10 rats in the exposure group and 10 rats in the control group. They were fed in air pollutant exposure system and clean experimental environment respectively, and the concentrations of PM2.5 and O3 in each system were measured. The degree of olfaction damage of SD rats at different feeding time was assessed by using the buried food test (BFT). The difference of BFT time between the two groups was analyzed by performing the repeated measures analysis of variance. Results: The results showed that the concentrations of PM2.5 and O3 in the exposure group were (22.65±11.47) μg/m3 and (12.36±5.87) μg/m3, respectively, while those in the control group were both 0 μg/m3. The repeated measures analysis of variance showed that the time of BFT in the exposure group was longer than that in the control group (F=6.49, P=0.031). With the increase of feeding time, the time of BFT was prolonged (F=61.69, P<0.001). Conclusion: Exposure to PM2.5 and O3 in the atmosphere might lead to olfaction damage in rats.