不同空气质量下河南主要城市冬季PM_(2.5)中重金属污染特征、来源解析及健康风险评价

Pollution characterization,source identification and health risk assessment of PM_(2.5)-bound metals in main cities of henan province in winter under different air quality levels

为研究不同大气污染水平条件下河南区域PM_(2.5)及其载带金属的浓度特征、来源和健康风险,于2020年12月在河南7个主要城市(郑州市、洛阳市、信阳市、安阳市、新乡市、商丘市、许昌市)采集PM_(2.5)样品,测定并分析了元素Cu、Zn、Pb、Se、Mn、Fe、As、Mo、Ni、Cd、Al.结果表明,PM_(2.5)中的重金属浓度峰值集中在轻度和中度污染空气质量条件,平均浓度顺序Zn>Fe>Al>Mn>Pb>Cu>As>Se>Mo>Cd>Ni.Zn和Fe平均质量浓度分别为118.92 ng·m^(-3)和52.88 ng·m^(-3),两者之和占重金属总浓度的65.88%.重金属富集因子变化趋势与浓度变化趋势相同,Cd元素的富集因子最高(>10),表明主要受人为活动影响.重金属元素的主要污染源为燃烧源和交通源.健康风险评估显示,所有空气质量条件下均为成年男性的致癌风险最大,儿童的非致癌风险最大.空气质量条件为优时,Mo对暴露于环境中1 h的成年男性和成年女性具有潜在致癌风险.

In order to study the concentration characteristics,source and risk assessment of PM_(2.5) and its carrying metals under different air pollution levels,PM_(2.5) samples were collected from 7 major cities of Henan province(Zhengzhou,Luoyang,Xinyang,Anyang,Xinxiang,Shangqiu,Xuchang)in December 2020.The elements of Cu,Zn,Pb,Se,Mn,Fe,As,Mo,Ni,Cd,Al in the samples were determined and analyzed.The results showed that the peak concentrations of heavy metals in PM_(2.5) were principally appeared under middle and moderate polluted air quality conditions.The average of mean mass concentration of metals was Zn>Fe>Al>Mn>Pb>Cu>As>Se>Mo>Cd>Ni.The average concentrations of Zn and Fe were 118.92 ng·m^(-3) and 52.88 ng·m^(-3) respectively,accounting for 65.88%of the total concentration of heavy metals.The variation trend of enrichment factors was identical with that of heavy metals concentrations.The enrichment factor value of Cd was the highest(>10),indicating Cd was primarily affected by human activities.The main sources of heavy metal elements were combustion sources and traffic sources,respectively.According to the health risk assessment,under all air quality conditions,adult males had the highest risk of cancer,while children had the highest risk of non-cancer.Under good air quality level,Mo had potential carcinogenic risk for adult male and female when exposing to the environment for 1 h.