Objective: To investigate the effect of PM2. 5on the respiratory tract flora in the SHR / NCrl rats.
Methods: Through the simulation of real air pollution and mixed gas exposure, the establishment of acute exposure to air pollution in low, medium and high concentration of animal models, to detect the distribution of bacterial flora before and after the dust exposure in the throat and respiratory mucosa of SHR rats. Analysis on the trend of micro ecology of respiratory tract was studied dynamically.
Results: The detection rate of anaerobic bacteria in SHR rats was 71. 8% and 20. 7% respectively, compared with the previous exposure to dust was high than 0. 6%, there were significant differences( P <0. 05). In the detection rate of anaerobic bacteria, the Tetanus bacillus and Clostridium in the respiratory tract of the exposed to dust rats was not detected. After the dust exposure, two kinds of bacteria respectively in 28 and 5 SHR rats were detected. The detection rate ofVeillonella in anaerobic bacteria was 53. 1%, there were significant differences( P <0. 05). The number of pathogenic bacteria in the aerobic bacteria after the dust exposure was increased, the detection rate also increased. The results showed that in the body the number and species of bacteria after the exposure to dust were changed.
Conclusion: PM_(2. 5) as the carrier of harmful substance, when with breathing enter the human respiratory tract, will cause the normal flora in the body 's respiratory tract disorder. The pathogen bacteria is easy to be colonized and the detection rate is increased, which affecting the body healthy.
Keywords: PM2. 5; SHR rat model; dust exposure; micro ecology; respiratory tract bacteria.