重庆市地铁车厢空气微生物污染状况调查

Investigation of air microorganism pollution in metro carriages in Chongqing

目的了解重庆市地铁车厢内不同季节空气中主要微生物的污染状况,为疾病预防和卫生监督提供科学依据。方法分别于2014年4、7、11月及2015年1月对重庆市地铁1、3号线车厢各进行1次细菌总数、溶血性链球菌菌落总数、温度、相对湿度等检测,同时监测客流量。每月连续检测3 d,每日分上午、下午2个时段,对每列车的前、中、后3段各抽取1节车厢进行检测。结果地铁1号线和3号线春、夏、秋、冬四季的细菌总数合格率分别为100%(144/144),97.92%(141/144),100%(144/144),100%(144/144)。细菌总数在夏季最高,为(15.14±1.42)CFU/皿;冬季最低,为(10.92±1.57)CFU/皿。多重线性回归分析结果显示,车厢内的细菌总数与车厢内温度、客流量呈正相关(P<0.05),细菌总数随着温度、客流量的增加而升高;车厢内的细菌总数与时间呈负相关(P<0.05),下午时的细菌总数少于上午。结论本次调查的地铁车厢内的空气质量主要与季节、客流量、温度有关,建议加强空调系统日常卫生管理。

Objective To understand the status of major microorganisms pollution in air of metro carriages in Chongqing in different seasons so as to provide scientific basis and reasonable suggestions for disease prevention and health supervision.Methods In April, July and November of 2014 and January of 2015, air samples in the front, middle and rear carriages of Line 1 and Line 3 were collected, the total bacterial colony count and hemolytic streptococcus colony detected, temperature,relative humidity and passenger flow recorded, accordingly. Results The qualified rate of total bacterial colony count was 100%（144/144）,97.92%（141/144）,100%（144/144）,100%（144/144）, respectively for April, July and November of 2014 and January of 2015. The highest count of the total number of bacterial colonies was detected in July, reached（15.14 ±1.42） CFU/dish, the difference was statistical significance（P〈0.05） compared with other period. With the increase of temperature and passenger flow inside the carriages, the total number of bacterial colonies increased significantly（ P〈0.05）. Conclusion Air quality inside the metro carriages is mainly related to the seasons, the passenger flow as well as temperature, and daily hygienic management of air conditioning system should be strengthened.