秦皇岛冬季典型污染时段PM2.5中重金属和PAHs的污染特征

为了探究近年来秦皇岛市大气中PM_2.5污染特征和影响因素，通过采集冬季重污染时段城区和开发区PM_2.5样品，使用等离子体发射光谱仪和气相色谱-质谱仪，分别测定城区样品中6种元素(Cu，Pb，Zn，Cr，Ni，Cd)和PAHs.结果表明，秦皇岛城区PM_2.5日平均质量浓度186μg/m³，开发区平均质量浓度为118.88μg/m³，城区PM_2.5中各重金属元素的浓度水平排序为Zn＞Pb＞Ni＞Cr＞Cu＞Cd，其中Cd为强-极强污染，Pb为中-强污染，Zn属于中等污染，Ni，Cu，Cr等其他元素基本无污染.PM_2.5中定性的检测到奈(Nap)、菲(Phe)、荧蒽(Fla)、芘(Pyr)、苯并(k)荧蒽(BkF)等单体.PM_2.5日浓度与风速具有显著的负相关性，与相对湿度呈正相关性.

Characteristics of Heavy Metal and PAHs in PM2.5 During Winter Pollution in Qinhuangdao

In order to explore the pollution characteristics and influencing factors of PM_2.5 in Qinhuangdao in recent years， the PM_2.5 samples from urban and development zones of Qinhuangdao during heavy pollution in winter were collected and analyzed. The quantities of 6 heavy metal elements(Cu， Pb， Zn， Cr， Ni， Cd)and polycyclic aromatic hydrocarbons(PAHs)in urban samples were determined by plasma emission spectrometer and gas chromatography-mass spectrometry. The results show that the average daily mass concentration of PM_2.5 in Qinhuangdao urban is 186μg/m³， and the average concentration in the development area is 118.88μg/m³. The sequence of concentrations of heavy metals in urban PM_2.5 are Zn > Pb > Ni > Cr > Cu > Cd. Among them， Cd is strong to strong pollution， Pb is medium to strong pollution， and Zn is medium pollution， other elements such as Ni， Cu， Cr are basically pollution-free. The monomers of PAHs， such as Naphthalene(Nap)， phenanthrene(Phe)， fluoranthene(Fla)， pyrene(Pyr)， benzo(k)fluoranthene(BkF)and so on， are qualitatively detected in these samples of PM_2.5. The daily concentration of PM_2.5 is negatively correlated with wind speed and positively correlated with relative humidity.