Influence of haze on air microbial concentrations in the student activity areas

Objective To understand the effect of haze on the distribution of microorganisms in the campus environments,and to provide basic information for environment improvement,disease prevention and control,as well as personal protections against haze.Methods Six core students activity areas were selected from a university in Baoding city,China,including a main road,a plaza,the only playground,a cafeteria,a classrooms and a dormitory.The total number of bacterial and fungal in the air were measured through sampling respectively in those places with the natural sedimentation method.The weather conditions have been divided into 4 degrees,including no haze pollution,mild haze pollution,moderate haze pollution and severe haze pollution.Results The concentrations of bacteria and fungus increased with the degrees of haze pollution in outdoor sampling areas,among which the main road had the highest impact.The concentrations of bacteria and fungus in the indoor sampling sites were not increased obviously with the increasing haze levels,but that in the dormitory was increased significantly(P<0.05).The bacterial concentrations outdoor were significantly higher than those of the indoor in moderate haze and severe haze days(P<0.05);the fungal concentrations outdoor were significantly higher than that of the indoor in severe haze days(P>0.05).Conclusion When the haze degree is more serious,the concentrations of bacteria and fungus in the outdoor environment of the campus were increased,but those of the indoor didn't change obviously.