大学校园室内PM_(2.5)重金属污染特征及其健康风险评价

Characteristics and health risk assessment of indoor PM_(2.5)-bound heavy metals in university campus

对2016年6—8月在南京市市区某大学校园宿舍和学生办公室采集的2种典型室内环境PM_(2.5)样品,利用电感耦合等离子体发射光谱仪分析PM_(2.5)中As,Cd,Cr,Ni,Cu,Fe,Mn,Pb和Zn等重金属元素浓度.采用富集因子法、地累积指数法和潜在生态风险指数法分别对重金属的污染程度进行评价,并评估大学生群体室内PM_(2.5)暴露健康风险.结果表明,室内PM_(2.5)平均质量浓度为(38. 50±15. 93)μg/m^3,元素Fe的质量浓度最高; Fe,Zn,Pb,Mn和Cu这5种元素为室内PM_(2.5)的主要元素,占总金属元素质量的96. 35%.利用3种污染评价方法得出的重金属元素污染程度排序和污染等级基本一致:Cd为极强污染,Pb和As为强到极强污染,Cr,Ni,Mn和Fe属于无和轻微污染.健康风险评价结果表明,室内PM_(2.5)中重金属致癌和非致癌风险均处于可接受范围内.

PM 2.5 samples in students dormitories and offices were collected in an urban university campus during June to August,2016 in Nanjing.Nine heavy metals bound to PM 2.5(As,Cd,Cr,Ni,Cu,Fe,Mn,Pb,and Zn)were analyzed by an inductively coupled plasma optical emission spectrometer(ICP-OES).The pollution assessment of heavy metals was conducted by enrichment factor,geoaccumulation index and potential ecological risk index,respectively.Then,the health risk assessment of the indoor PM 2.5 exposure of students was evaluated.The results showed that the average mass concentration of indoor PM 2.5 was(38.50±15.93)μg/m 3.The mass concentration of Fe was the highest among the tested nine heavy metals bound to indoor PM 2.5.Fe,Zn,Pb,Mn,and Cu are the main constituents of metal elements and accounted for 96.35%of the total elements.The pollution level and the sequence of heavy metals evaluated by the mentioned three pollution assessment models are generally consistent:Cd is extremely contaminated;Pb and As are heavily to extremely contaminated;Cr,Ni,Mn and Fe are lightly contaminated.The health risk assessment indicates that carcinogenic and non-carcinogenic risks of tested heavy metals bound to indoor PM 2.5 are within safe limits.