摘要
目的了解重庆市某中心城区空气细颗粒物(PM_(2.5))中16种多环芳烃(PAHs)的分布状况,并分析其来源,为防治环境污染和保护人群呼吸健康提供参考依据。方法于2019年2月-2020年1月,在重庆市某中心城区市控环境空气质量监测站1 km覆盖范围内某小学设置采样点,每月10-16日采集PM_(2.5)样品,用GC-MS测定PM_(2.5)中的16种PAHs的含量,分析变化规律,并利用特征比值法、主成分分析法识别PAHs来源。结果共检出16种PAHs,全年PM_(2.5)中PAHs总浓度变化范围为1.09~11.83 ng/m~3,均值5.22 ng/m~3。冬季浓度高于其他季节,夏季浓度最低,呈明显的U型变化趋势。PM_(2.5)中以5环、6环PAHs为主,其质量浓度之和占总PAHs的61.3%,显示出明显的机动车尾气排放特征。特征比值法揭示重庆市某中心城区PAHs来源于机动车柴油和汽油尾气的排放,主成分分析法表明重庆市某中心城区机动车尾气排放与天然气燃烧(52.46%)、燃油挥发(19.97%)、生物质燃烧(7.72%)是PAHs的主要污染源。结论重庆市某中心城区空气PM_(2.5)中PAHs浓度冬季最高、夏季最低,PAHs污染主要来源为机动车尾气排放。
Objective To understand the distribution of 16 polycyclic aromatic hydrocarbons(PAHs)in air PM_(2.5)in a urban center of Chongqing city and analyze the sources,so as to provide a reference basis for preventing environmental pollution and protecting the respiratory health of the population.Methods From February 2019 to January 2020,a sampling point was set up at an elementary school within the 1 km coverage of a municipal controlled ambient air quality monitoring station in a central city of Chongqing city,and PM_(2.5)samples were collected from the 10th to the 16th of each month.GC-MS was used to determine the contents of 16 PAHs in PM_(2.5),the change pattern was analyzed,and the sources of PAHs were identified by using the characteristic ratio method and principal component analysis.Results A total of 16 PAHs were detected.The total concentration of PAHs in PM_(2.5)varied from 1.09-11.83 ng/m^(3) throughout the year,with an average value of 5.22 ng/m^(3).The concentration was higher in winter than in other seasons and lowest in summer,showing a clear U-shaped trend.PM_(2.5)was dominated by 5-ring and 6-ring PAHs,and the sum of their mass concentrations accounts for 61.3%of the total PAHs,showing obvious characteristics of motor vehicle exhaust emissions.The characteristic ratio method reveals that PAHs in the region originate from diesel and gasoline exhaust emissions from motor vehicles.The principal component analysis method showed that motor vehicle exhaust emissions with natural gas combustion(52.46%),fuel oil volatilization(19.97%),and biomass combustion(7.72%)were the main sources of PAHs in the region.Conclusion Concentrations of PAHs in PM_(2.5)in the region are highest in winter and lowest in summer in a urban center of Chongqing city.The main source of PAHs pollution is motor vehicle exhaust emissions.
作者
曾晓龙
周杰
胡雪郢
薛丰
邓雪
刘淼
曾云夏
ZENG Xiao-long;ZHOU Jie;HU Xue-ying;XUE Feng;DENG Xue;LIU Miao;ZENG Yun-xia(Yuzhong District Center for Disease Control and Prevention,Chongqing 400010,China)
出处
《预防医学论坛》
2023年第7期524-528,共5页
Preventive Medicine Tribune
关键词
PM_(2.5)
多环芳烃
主成分分析
污染特征
来源分析
PM_(2.5)
Polycyclic aromatic hydrocarbons(PAHs)
Principal component analysis(PCA)
Pollution characteris-tics
Analysis of sources
