珠三角城乡大气有机气溶胶来源、生成机制及吸入沉积通量  

Source,formation mechanism and inhalation deposition flux of organic aerosols in urban and rural areas of the Pearl River Delta

作　　者：伍莉娜 黄山 刘袁 宋奇聪 胡伟伟 陈卫 旷烨 王小月 李伟 彭钰雯 陈多宏 岳玎利 宋伟 袁斌 王新明[3] 邵敏 WU Lina;HUANG Shan;LIU Yuan;SONG Qicong;HU Weiwei;CHEN Wei;KUANG Ye;WANG Xiaoyue;LI Wei;PENG Yuwen;CHEN Duohong;YUE Dingli;SONG Wei;YUAN Bin;WANG Xinming;SHAO Min(Institute for Environmental and Climate Research,Jinan University,Guangzhou 511443;Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality,Guangzhou 511443;State Key Laboratory of Organic Geochemistry,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640;Guangdong Ecological and Environmental Monitoring Center,State Environmental Protection Key Laboratory of Regional Air Quality Monitoring,Guangzhou 510308)

机构地区：[1]暨南大学环境与气候研究院,广州511443 [2]粤港澳环境质量协同创新联合实验室,广州511443 [3]中国科学院广州地球化学研究所,有机地球化学国家重点实验室,广州510640 [4]广东省生态环境监测中心,国家环境保护区域空气质量部检测重点实验室,广州510308

出　　处：《环境科学学报》2024年第1期15-28,共14页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金项目(No.41807302);国家重点研发计划项目(No.2017YFB0503901);广东省自然科学基金面上项目(No.2018A030313384);广东省科技创新战略专项(No.2019B121205004)。

摘　　要：为探究珠三角地区秋季亚微米有机气溶胶(OA)的污染特征、健康风险及其城乡差异,本研究对基于黑碳高分辨率飞行时间气溶胶质谱仪(SP-AMS)观测的广州(城市)及鹤山(乡村)气溶胶数据进行了分析.结果显示,在城乡的两次秋季观测期间,PM,平均质量浓度分别为(29.87±20.11)μg·m^(-3)和(40.08±16.05)μg·m^(-3),其中OA占比最高,分别为57.4%和52.1%.基于正交矩阵因子分析法(PMF)进行来源解析,发现在珠三角城乡两地二次有机气溶胶都是OA的首要组分,分别占64.0%和66.7%.城市地区OA受日间光氧化反应贡献明显,而乡村地区OA在夜间至清晨出现显著抬升,可能与夜间二次生成相关.相对湿度(RH)升高指示的液相反应及日间光氧化对城市低氧化态OA生成均有促进作用,光氧化也能促进乡村低氧化态OA的日间生成,而夜间SOA(Night-OA)则主要在高RH的条件下贡献更为显著.基于模型计算了亚微米级OA在人体呼吸系统中的分粒径沉积通量,发现其在肺泡区域沉积通量最大,两地沉积通量的粒径分布呈现双峰分布,但城区OA在小粒径(120 nm)的沉积峰值更加突出,因此可能具有更大的健康风险.To investigate the pollution characteristics,health risks of submicron organic aerosols(OA)and their urban/rural discrepancy in the Pearl River Delta(PRD),comprehensive analysis was performed based on data from soot particle aerosol mass spectrometer(SP-AMS)measurements at Guangzhou(urban)and Heshan(rural)sites of the PRD.Average PM1 mass concentrations were(29.87±20.11)μg∙m^(-3) and(40.08±16.05)μg∙m^(-3) in urban and rural PRD during two fall campaigns,respectively,both dominated by organics(57.4%and 52.1%,respectively).Based on OA source apportionment using positive matrix factorization(PMF),secondary organic aerosol(SOA)was the largest contributor to OA,accounting for 64.0%and 66.7%,respectively.In urban PRD,OA was significantly contributed by daytime photo-oxidation,while in the rural region,OA showed a significant elevation from nighttime to early morning,which may be related to secondary formation at night.Both aqueous-phase reactions indicated by increasing relative humidity(RH)and photo-oxidation may enhance formation of the less-oxygenated OA in the urban area.In the rural region,the less-oxygenated OA was mainly produced via photo-oxidation,while nighttime SOA(Night-OA)formation was enhanced by high RH.Size-resolved OA deposition flux in the human respiratory system was calculated by model and showed that the deposition flux had a bimodal distribution,and occurred mainly in the pulmonary alveoli.In the urban atmosphere,OA deposition flux exhibited a more prominent peak near 120 nm,which can cause more adverse health effects.

关 键 词：有机气溶胶(OA) 来源解析 污染特征 沉积通量 黑碳气溶胶质谱仪 珠三角地区 

分 类 号：X513[环境科学与工程—环境工程]