AUTHOR=Huang Yuhan , Ropkins Karl , Yuan Bin , Yao Lei , Huang Liubin TITLE=Editorial: Urban air pollution: sources, characterization and mitigation JOURNAL=Frontiers in Environmental Science VOLUME=11 YEAR=2023 URL=https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2023.1349491 DOI=10.3389/fenvs.2023.1349491 ISSN=2296-665X