Air Pollution Study in Bangkok Metropolis and its Boundary

Abstract:

Airborne particulate matter (APM) is apparently the biggest air pollution problem found in capital and other big cities. APM, particularly PM10 has the adverse impact on human health, environment and also cause of visibility impairment. This work reports the study of air pollution in Bangkok and its boundary. Coarse and fine fractions of PM10 (PM2.2-10 and PM2.2, respectively) were collected from January 2003 to December 2006 at an urban Bangkok area (Chatuchak district) and a suburban area (Klongha district, Pathumthani). The filter samples were measured for mass and black carbon. Then, up to 29 elemental concentrations were determined using Instrumental Neutron Activation Analysis (INAA) and Particle-Induced X-ray Excitation (PIXE). A receptor model called Positive Matrix Factorization (PMF) was applied for the APM source apportionment. The long-term base of data shows that APM in the urban area had higher concentrations of mass, black carbon and most other elements than at the suburban area. Furthermore, it was found that the mass and elemental concentrations were generally elevated in the coarse fraction whereas black carbon was the major constituent in fine fraction. The PMF results indicate that major sources contributing to the coarse fraction samples were soil, construction while traffic and sulfate were the primary contributors to fine fraction samples. Biomass burning contributed to both PM size-fractions at both sites. Thus, biomass burning could be the most significant air pollution problem in both the urban and suburban areas. Using of meteorological information, particularly wind direction with the source contributions resulting from the PMF analysis enhanced the understanding of air pollution system being studied.

Keywords: airborne particulate matter, Bangkok, source apportionment