| 摘要: |
| 为了解山西省运城市大气细颗粒物（PM2.5）中重金属的污染特征和来源及其健康风险，于2020年10月15日—2021年2月14日对运城市大气PM2.5样品进行连续采集，使用微波消解-电感耦合等离子质谱法（ICP-MS）分析了样品中的铬（Cr）、锰（Mn）、镍（Ni）、铜（Cu）、锌（Zn）、砷（As）、镉（Cd）和铅（Pb）等8种重金属元素的质量浓度。结果表明，采样期间，ρ（PM2.5）平均值为78.96μg/m3，采暖季ρ（PM2.5）为（79.84±43.79）μg/m3，高于非采暖季（76.54±23.97）μg/m3，采暖季和非采暖季ρ（PM2.5）均值均超过《环境空气质量标准》（GB 3095—2012）中的二级标准。富集因子法分析表明，Ni、Cu、Zn、As、Cd和Pb的富集因子均高于10，其中Cd元素的富集因子平均值达到1.089，表明受人为污染影响严重。主成分分析结果表明，运城市区秋冬季大气中重金属主要有3个来源，分别为混合燃烧源、机动车尾气源、工业排放源。健康风险评价结果显示，经手口摄入暴露强度最大，呼吸吸入暴露强度最小，皮肤接触暴露强度居中；儿童在3种暴露途径的总暴露剂量高于成人，儿童重金属暴露风险高于成人。各途径的非致癌风险强度叠加值＜1，表明非致癌风险较小；但As、Pb的非致癌风险相对较高。4种重金属的呼吸吸入途径致癌风险程度排序为：As＞Cr＞Cd＞Ni，单种重金属的致癌风险（TR）值以及重金属的总致癌风险（R）值均＜10-6，表明本研究中重金属不具有致癌风险。 |
| 关键词: 细颗粒物 重金属；污染特征；富集因子；主成分分析；健康风险评价；运城市 |
| DOI：10.3969/j.issn.1674-6732.2023.05.024 |
| 分类号:X828 |
| 基金项目:大气重污染成因与治理攻关项目（DQGG202110） |
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| Pollution Characteristics and Health Risk Assessment of Heavy Metals in PM2.5 in Autumn and Winter in Yuncheng City |
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LI yuxia1， ZHAO Zhengyu2， GU Xin2， LI Xingru2*
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1.College of Resource Environment and Tourism， Capital Normal University， Beijing 100048, China； 2. Department of Chemistry， Analytical and Testing Center， Capital Normal University， Beijing 100048， China
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| Abstract: |
| In order to understand the pollution characteristics， sources and health risks of heavy metals in atmospheric PM2.5 in Yuncheng City， the atmospheric PM2.5 samples of Yuncheng City were continuously collected from October 15，2020 to February 14，2021. The mass concentrations of chromium（Cr），manganese（Mn）， nickel（Ni）， copper（Cu）， zinc（Zn）， arsenic（As）， cadmium（Cd） and lead（Pb） in the samples were analyzed by microwave digestion and inductively coupled plasma mass spectrometry（ICP-MS）. The results showed that during the sampling period， the average mass concentration of PM2.5 was 78.96 μg/m3， and the mass concentration of PM2.5 in heating season（79.84±43.79）μg/m3 was higher than that in non-heating season（76.54±23.97）μg/m3. The average mass concentration of PM2.5 in both heating season and non-heating season exceeded the secondary standard（75 μg/m3） set by Ambient Air Quality Standard（GB 3095—2012）. The enrichment factor analysis showed that the enrichment factors of Ni， Cu， Zn， As， Cd and Pb were all higher than 10， and the average enrichment factor of Cd was 1.089， indicating that it was seriously affected by anthropogenic pollution. The results of principal component analysis show that there are three main sources of heavy metals in the atmosphere of Yuncheng City in autumn and winter， which are mixed combustion source， motor vehicle exhaust source and industrial emission source. The results of health risk assessment showed that the exposure intensity was the highest through hand oral ingestion， the lowest through respiratory inhalation， and the medium through skin contact. The total exposure dose of children in the three exposure routes was higher than that of adults， and the risk of heavy metal exposure in children was higher than that of adults. The superposition value of the non carcinogenic risk intensity of each pathway is less than 1， indicating that the non-carcinogenic risk is small， but the non-carcinogenic risk of As and Pb is relatively high. The carcinogenic risk degree of the four heavy metals in respiratory inhalation pathway ranks as follows：As＞Cr＞Cd＞Ni， and the carcinogenic risk（TR） value of a single heavy metal and the total carcinogenic risk（R） value of heavy metals are less than 10-6， indicating that heavy metals in this study do not have carcinogenic risk. |
| Key words: PM2.5 Heavy metal Pollution characteristics Enrichment factor Principal component analysis Health risk assessment Yuncheng |
