摘要：为了深入探究枣庄市大气PM2.5颗粒物浓度动态变化特征、重金属元素的健康风险和污染来源,通过2017年12月—2020年3月的连续采样监测,采用健康风险评价模型研究12种PM2.5重金属元素的暴露评价和危险度特征,使用正定矩阵因子分解模型(PMF)定量解析了近3a采暖季各源因子对PM2.5的贡献。结果表明:1)枣庄市大气PM2.5及重金属污染集中于采暖季,PM2.5重金属元素质量浓度为Al> Zn> Cu> Pb> Mn> As> Cd> Hg>Ni> Cr> Sb> Se,致癌性重金属元素As、Cd、Cr的年均值超过国家标准限值; 2) PM2.5中12种重金属元素的年均超额危险度均未超过人群可接受危险水平标准,但来自冶金和燃煤等工业排放的Cr和As潜在风险较大; 3)采暖季PM2.5重污染的各排放源贡献率为二次源(39.6%)>燃煤源(20.5%)>扬尘源(14.4%)>机动车源(10.4%)>其他源(7.7%)>工业源(7.4%);从PMF解析结果分析得出,PM2.5中重金属元素主要来源于扬尘(44.5%)、燃煤(20.4%)、工业(19.1%)和机动车(14.4%)排放。
关键词：健康风险评价；PM2.5；正定矩阵因子分解；重金属；枣庄市
Abstract: The dynamic characteristics of PM2．5 concentrations，health risks of heavy metal elements，and pollution sources was investigated in Zaozhuang city，through a continuous interval sampling monitoring analysis from December 2017 to March 2020． We used the USEPA health risk assessment model studied the exposure evaluation and hazard characteristics of 12 heavy metal elements． The contribution of each source factor to PM2．5 during the heating season in the last three years was quantified by PMF model． We conclude that: 1) Heavy PM2．5 periods are concentrated in the heating season，and the mass concentrations of heavy metal elements are Al ＞ Zn ＞ Cu ＞ Pb ＞ Mn ＞ As ＞ Cd ＞ Hg ＞ Ni ＞ Cr ＞ Sb ＞ Se． The annual average values of carcinogenic heavy metal As，Cd and Cr exceed the national standard limit values． 2) The annual average excess risk levels of 12 heavy metal elements in atmospheric PM2．5 are all below the acceptable risk level． The potential risk of Cr and as which are from metallurgy and coal-fired industry is alarming． 3) The contributions of sources in the heating season: secondary source ( 39．6% ) ＞ coal-fired source ( 20．5% ) ＞ dust source ( 14．4% ) ＞ motor vehicle source ( 10．4% ) ＞ other source ( 7．7% ) ＞ industrial source ( 7．4% ) ． Furthermore，the analysis of PMF showes that the heavy metals in PM2．5 are mainly from emissions of dust ( 44．5% ) ，coal combustion ( 20．4% ) ，industrial ( 19．1% ) ，and motor vehicle ( 14．4% ) ．
Keywords: health risk assessment; PM2．5 ; positive matrix factorization( PMF) ; heavy metal; Zaozhuang city
