Comparative Evaluation of Post-Monsoon Crossroads Air Quality Variations in Major Cities of the Greater Dhaka Region

Abstract

This study investigates the escalating issue of urban air pollution in Dhaka and its surrounding areas, focusing on the post-monsoon period. Utilizing Aeroqual Series 500 air quality monitors, this research measured concentrations of NO2, SO2, CO2, CH4, PM2.5, and PM10 at 24 strategically selected sites in Dhaka, Narayanganj, and Gazipur. The findings reveal elevated levels of NO2 across multiple regions, notably exceeding the standard threshold of 0.053 ppm, with Gulistan, Mirpur10, Gabtuli Darus-salam, Farmgate, and Savar exhibiting the highest concentrations. Additionally, Gulistan displayed a significant peak in SO2 levels at 0.3 ppm. Areas adjacent to the Buriganga River, specifically Lalbagh and Kadamtuli, were identified as heavily polluted as they have been characterized by strong odour and poor air quality. High concentrations of CH4 and CO2 were detected in the New Market, Zinda Park, and Jirani Bazar, surpassing established safe levels. The study highlights Dhaka's alarming average Air Quality Index (AQI) of 186.8, with a peak of 395 at Joydebpur Rail Station and a low of 110 at Panam City. This research underscores the critical need for enhanced air quality monitoring and control strategies in Dhaka, highlighting the severe health risks posed by industrial and vehicular emissions in rapidly urbanizing regions.