PM2.5, PM10 air pollution and associated heavy metals in traffic congested and construction areas of Bangkok

Abstract

The capital city of Thailand, Bangkok, is facing a serious problem caused by overpopulation and traffic congestion. In the this work, particulate matter, both PM2.5 (diameter < 2.5 μm) and PM10 (diameter < 10 μm) were quantified at the road nears construction areas and road with high traffic; compared with a control area. The sampling area comprised of Pattanakarn Road and Srinagarindra Road located on the eastern route, located between the inbound and outbound junction. Mini-volume air sampler was used to collect PM2.5, while cyclone air samplers were used to collect PM10. The samples were collected from November to December 2018, for 12 hours per day for 5 days at each sites. The collected samples were then digested by using microwave digestion for heavy metal components like Fe, Cu, Zn, Cd and Pb. Then, they were analyzed by Graphite Furnace Atomic Absorption Spectrometry (GFAAS) to quantify the heavy metal concentrations. Video recorders were installed at each sampling areas to monitor the traffic flow and it was found that construction areas were the most crowded. The average PM2.5 and PM10 concentrations in the construction areas were higher than those in traffic areas with no construction and the background site (a park), which had no impacts from construction and traffic. Heavy metals associated with particulate matter emitted during construction activities is an emerging environmental issue; however, construction activities are required for convenience and development. This study provides important data required to monitor the future trends of air pollution sources.