Trace elemental composition and source identification of PM2.5 in the metropolitan area of Bangkok, ThailandSasikarn Nuchdang, Wilasinee Kingkam, Udomrat Tippawan, Piyanud Thongjerm, Sarinrat Wonglee, Weerawat Pornroongruengchok, Chantaraporn Phalakornkule, Unchalee Suwanmanee and Dussadee RattanaphraE3S Web Conf., 712 (2026) 02002DOI: https://doi.org/10.1051/e3sconf/202671202002