Evaluation of Mass Concentration and Size Distribution of Fine Particles (PM2.5) in Bien Hoa City, Dong Nai Province

Air pollution is one of the most concerning environmental issues, in which fine inhalable particles (PM2.5, with diameters that are generally 2.5 micrometers and smaller) concentration plays a key part. Bien Hoa city contains and locates close to several large industrial zones that might create sources of PM2.5 polluting the local air quality. This study monitors and evaluates PM2.5 concentration trends in Bien Hoa airport of Dong Nai province. PM samples are analyzed by Scanning Electron Microscopy (SEM) to recognize the surface pattern and size distributions are analyzed by ImageJ software. Ten samples of PM2.5 were obtained from sampling collected in October 2021. The results show that 24-h PM2.5 mass concentrations were from 15.2 µg/m3 - 50.4 µg/m3 with an average of 28.2 µg/m3; median of 24.1 µg/m3; and standard deviation of 12.2 µg/m3. The values are lower than the Vietnam National Technical Regulation on Ambient Air Quality (QCVN 05:2013/BTNMT) but far higher than the recommended values of the World Health Organization (WHO). SEM and image results indicate the distributions of the particles of 2.0 - 2.5 µm are minor, where the majority are particles with aerodynamic diameter ≤ 1.0 µm. Keywords: Air pollution; Fine particulate matters; PM2.5; Size distribution, Bien Hoa, Dong Nai.