“…; to study the trend and characteristics of PM 2.5 ( Chen et al, 2020 ; Fontes et al, 2017 ; Sreekanth et al, 2018 ; Liang et al, 2016 ; Batterman et al, 2016 ; San Martini et al, 2015 ), to compare with other data and model evaluation ( Jiang et al, 2015 ; Li, 2020 ; Matthias et al, 2017 ; Mukherjee and Toohey, 2016 ; Shimadera et al, 2016 ; Uno et al, 2014 ; Wang et al, 2018 ), and to estimate the health impacts ( Han et al, 2020 ; Lowsen and Conway, 2016 ; Luong et al, 2020 ; Nhung et al, 2020 ; Tian et al, 2020 ; Wang et al, 2020 ; You et al, 2016 ; Zhang et al, 2020 ). While most of the studies are carried out in China, few studies have been carried out for other countries including Vietnam ( Hien et al, 2019 ; Luong et al, 2020 ), Japan ( Shimadera et al, 2016 ) Indonesia ( Kusuma et al, 2019 ), Mongolia ( Hill et al, 2017 ), Bangladesh ( Auvee and Bashar, 2019 ), and Singapore ( Liu and Salvo, 2018 ).…”