北京市PM2.5污染特征、来源分析及其重金属健康风险评价

The pollution characteristics,sources of PM2.5 in Beijing and health risk assessment of its heavy metals

分析了2016年北京市的PM 2.5及其中的Zn、Pb、Mn、Cu、Cr、As、Ni、Cd、Sb、Co、V、Ba、Al、Fe、Mg、Ti、Ca、S 18种元素含量,并对重金属As、Cr、Pb、Cd、Ni、Mn、Cu和Zn进行了相应的健康风险评价。结果表明:PM 2.5质量浓度为14.63~206.35μg/m^3,年平均值为74.00μg/m^3,超过《环境空气质量标准》(GB 3095—2012)二级标准(35μg/m^3)1倍多;PM 2.5中S、Zn、Sb、Pb和Cd的富集程度较高,主要来源于机动车尾气排放、燃煤和工业活动;Mn、Pb、Cr、Zn、Cu、As、Cd、Ni 8种重金属对儿童、成人女性、成人男性的非致癌总风险均小于1,不存在非致癌风险;As、Cd、Cr和Ni 4种重金属的致癌风险为1.94×10^-7~6.04×10^-5,均小于10^-4,部分重金属可能存在潜在致癌风险,主要是As和Cr存在潜在致癌风险。

The concentration of PM 2.5 and its 18 elements(Zn,Pb,Mn,Cu,Cr,As,Ni,Cd,Sb,Co,V,Ba,Al,Fe,Mg,Ti,Ca and S)in Beijin of 2016 were analyzed,and the health risks of heavy metals(As,Cr,Pb,Cd,Ni,Mn,Cu and Zn)were assessed.Results showed that PM 2.5 mass concentrations was 14.63-206.35μg/m^3,with an annual average of 74.00μg/m^3,which exceeded second grade(35μg/m^3)of“Ambient air quality standards”(GB 3095-2012)for more than 1 time.S,Zn,Sb,Pb and Cd in PM2.5 were concentrated,which were mainly derived from vehicle exhaust emission,coal combustion and industrial activities.The non-carcinogenic risks of As,Cr,Pb,Cd,Ni,Mn,Cu and Zn for children,female adults and male adults were all below 1,indicating they had no non-carcinogenic risk.The carcinogenic risks of As,Cd,Cr and Ni were 1.94×10^-7-6.04×10^-5(below 10^-4),indicating that part of the heavy metals(mainly As and Cr)presented potential carcinogenic risk to human.