Environmentally persistent free radicals in PM_(2.5)from a typical Chinese industrial city during COVID-19 lockdown:The unexpected contamination level variation  

作　　者：Lingyun Wang Wuduo Zhao Peiru Luo Qingyun He Wenfen Zhang Chuan Dong Yanhao Zhang 

机构地区：[1]College of Chemistry,Zhengzhou University,Zhengzhou 450001,China [2]Center of Advanced Analysis and Gene Sequencing,Key Laboratory of Molecular Sensing and Harmful Substances Detection Technology,Zhengzhou University,Zhengzhou 450001,China [3]State Key Laboratory of Environmental and Biological Analysis,Department of Chemistry,Hong Kong Baptist University,Hong Kong 999077,China [4]Institute of Environmental Science,Shanxi University,Taiyuan 030006,China

出　　处：《Journal of Environmental Sciences》2024年第1期424-432,共9页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos.22106129,22076174 and 91843301)。

摘　　要：The outbreak of COVID-19 has caused concerns globally.To reduce the rapid transmission of the virus,strict city lockdown measures were conducted in different regions.China is the country that takes the earliest home-based quarantine for people.Although normal industrial and social activities were suspended,the spread of virus was efficiently controlled.Simultaneously,another merit of the city lockdown measure was noticed,which is the improvement of the air quality.Contamination levels of multiple atmospheric pollutants were decreased.However,in this work,24 and 14 air fine particulate matter(PM_(2.5))samples were continuously collected before and during COVID-19 city lockdown in Linfen(a typical heavy industrial city in China),and intriguingly,the unreduced concentration was found for environmentally persistent free radicals(EPFRs)in PM_(2.5)after normal life suspension.The primary non-stopped coal combustion source and secondary Cu-related atmospheric reaction may have impacts on this phenomenon.The cigarette-based assessment model also indicated possible exposure risks of PM_(2.5)-bound EPFRs during lockdown of Linfen.This study revealed not all the contaminants in the atmosphere had an apparent concentration decrease during city lockdown,suggesting the pollutants with complicated sources and formation mechanisms,like EPFRs in PM_(2.5),still should not be ignored.

关 键 词：PM_(2.5) EPFRs COVID-19 City lockdown Health risks 

分 类 号：X513[环境科学与工程—环境工程]