郑州市空气中细菌含量及其变化规律研究

The concentration and variation of airborne bacteria in Zhengzhou city

目的探究郑州市城区空气细菌含量、变化规律及其与空气中PM10浓度的关系,为户外活动人群提供指导。方法用六级筛孔撞击式空气微生物采样器分别于郑州市5个采样点处采集空气中细菌,采样后平皿在37℃下培养48 h后计数。结果郑州市城区3、4、5、6、7、8月份空气细菌含量变化范围在148~2 045 cfu/m3(cfu:菌落形成单位),月平均含量为686 cfu/m3。各个采样点空气细菌月平均含量(cfu/m3)分别为:河医大(974)、烟厂(832)、供水公司(647)、银行学校(520)、四十七中(457);同时,空气细菌含量呈现月份变化趋势。细菌含量与PM10浓度相关系数为0.40(P=0.028<0.05),呈现中等相关性。结论郑州市城区空气细菌含量呈现区域差异和月份变化趋势,与PM10呈现具有统计学差异的正相关。易感人群应注意防范,同时公众应注意预防大规模空气微生物感染的风险。

Objective To investigate the concentration, variation of airborne bacteria and the relationship between the concentration of airborne and PM10 in Zhengzhou city and provide guidance for the activity of outdoor people.Methods We collected the airborne bacteria in five places in Zhengzhou city with a 6-mesh impact type air microorganism sampler, and then the Petri-dishes were cultured at 37 degrees Celsius for 48 hours.Results The concentration of airborne bacteria in Zhengzhou city from March to August ranged from 148 to 2 045 cfu （colony-forming unit） per cubic meters, and the average concentration was 686 cfu per cubic meters.The monthly average concentration of outdoor airborne bacteria at the Henan Medical University, the cigarette factory, water supply company, banking school and the 47th middle school were 974, 832, 647, 520 and 457 cfu per cubic meters respectively;furthermore, the concentration of airborne bacteria from March to August had a monthly change.The correlation coefficient of concentration of airborne and PM10 was 0.40 （P=0.028〈0.05）, which indicated a moderate correlation.Conclusion The concentration of airborne bacteria in Zhengzhou city has a regional difference, a variation trend of month, and a significant positive correlation with the concentration of PM10.The susceptible population should pay attention.Furthermore, the public should anticipate the risk of airborne infection in large scale.