人员密集型场所细菌真菌气溶胶冬季分布特征及健康影响分析

Distribution Characteristics and Health Impact Assessment of Bacterial and Fungal Aerosols in Densely Populated Places in Winter

地铁、超市、电子市场、医院挂号大厅等都属于人员数量多且活动多的密集型场所,其室内空气中的细菌真菌污染不容忽视。为了解这些人多场所内的细菌真菌气溶胶浓度及不同粒径段微生物的分布,于2019年冬季首先对四类场所内的细菌和真菌气溶胶进行了现场采样和实验分析,并测试了其它环境参数;然后分析了不同场所内细菌真菌气溶胶的浓度水平及分布特征;最后,评估了不同场所微生物气溶胶的浓度水平及可能产生的健康风险。结果表明:1)细菌气溶胶浓度均值为电子市场>超市>医院>地铁,其中电子城内细菌气溶胶浓度为838 cfu/m^(3),地铁内细菌为449 cfu/m^(3);真菌气溶胶浓度均值为超市>电子市场>医院>地铁,其中超市内真菌气溶胶浓度为558 cfu/m^(3),地铁内真菌为282 cfu/m^(3);2)细菌气溶胶中值直径为医院>地铁>电子市场>超市,真菌气溶胶中值直径为电子市场>医院>地铁>超市,且场所内细菌、真菌气溶胶中值直径均小于室外细菌真菌气溶胶中值直径;3)地铁、超市、电子市场内空气中的细菌主要集中在第Ⅰ级(>7μm)、第Ⅳ级(2.1~3.3μm)和第Ⅴ级(1.1~2.1μm)粒径段,医院空气中细菌主要集中在第Ⅰ级、第Ⅱ级(4.7~7μm)和第Ⅳ级粒径段;真菌气溶胶主要分布在第Ⅲ级(3.3~4.7μm)、第Ⅳ级和第Ⅴ级粒径段;4)测试区域内电子市场配件区细菌气溶胶浓度最高,地铁站台最低,分别为1 074 cfu/m^(3)、194 cfu/m^(3);真菌气溶胶浓度最高和最低的分别为超市蔬菜区和地铁站台,分别为614 cfu/m^(3)和113 cfu/m^(3);5)4类场所细菌气溶胶水平均为较清洁,真菌在超市中为较清洁,在地铁、医院大厅和电子市场内为清洁;6)所有场所微生物气溶胶的健康影响系数均显著小于1,健康风险较低。

Subway,supermarkets,electronic markets,hospital registration halls are all densely populated places with a large number of people and activities,and the fungi and bacteria pollution in the indoor air cannot be ignored.In order to study the concentrations of fungi and bacteria aerosols and the microbial distribution in different particle sizes in these densely populated places,this study collected and analyzed the fungi and bacteria aerosols in the indoor air of the above four types places in 2019 winter.And other indoor environmental parameters were measured onsite as well.Then,the concentrations and distributions of fungi and bacteria aerosols in dfferent places were analyzed and discussed.The concentrations of microbial aerosol and their possible health risks in different types of places were evaluated.The results showed that:1)The ranking of the average concentration of bacteria aerosol in four places was Electronic market>Supermarket>Hospital>Subway,with that in electronic markets and subway being 838 cfu/m'and 449 cfu/m^(3),respectively.The ranking of the average concentration of fungi aerosol in four places was Supermarket>Electronic market>Hospital>Subway.The concentrations of fungal aerosols in Supermarket and Subway were 558 cfu/m'and 282 cfu/m,respectively.2)The median diameter of the bacteria aerosol in four places was Hospital>Subway>Electronic market>Supermarket,while that of the fungal aerosol was Electronic market>Hospital>Subway>Supermarket.Additionally,the median diameters of bacteria and fungi aerosol indoors were smaller than those outdoors in four places.3)The bacterial particle sizes in the air of Subway,Supermarket,and Electronic market mainly fall into grade I(>7μm),grade IV(2.1~3.3μm),and grade V(1.1~2.1μm),while those in the air of Hospital are mainly concentrated in grade I(>7μm),grade II(4.7~7μm)and grade IV.The fungal particle sizes in the air of four places mainly fall into grade III(3.3~4.7μm),grade IV,and grade V.4)The accessory area of the electronic market had the highest concentration of bacteria aerosols in the air,with the value of 1,074 cfu/m,while the Subway had the lowest concentration of 194 cfu/m.The highest concentration of fungal aerosol was found in the vegetable area of Supermarkets,with a value of 614 cfu/m',while the lowest concentration of 113 cfu/m^(3) was observed in the Subway station.5)The pollution level of bacteria aerosols in the air of the four places was relatively low.The pollution level of fungi in Supermarkets was relatively low and that in Subway,Hospitals,and Electronic markets was low.6)The health impact coefficients of microbial aerosol in four places were all significantly smaller than 1,indicating low health risks.