Apportionment of particulate matter and assessment of elemental particle exposure by spatiotemporal variations in Dhaka’s microenvironments

Description

Particulate matter (PM) pollution in Dhaka exhibits pronounced temporal variability, reflects a complex mixture of emission sources, and contributes substantially to exposure across both outdoor and indoor environments. However, measurements that simultaneously resolve PM2.5, PM10, black carbon (BC), elemental composition, reconstructed mass components, and exposure-related risk indicators across contrasting institutional settings remain limited; therefore, this study was conducted from February to May 2024 in two study areas (i.e., University of Dhaka and Atomic Energy Centre, Dhaka) using gravimetric methods. The findings revealed extremely elevated PM2.5 concentrations, with peak values of 143.19, 106.67, 178.19, 143.19, and 96.94 µg/m3. Elevated PM10 concentrations were also detected, reaching maximum levels of 310.89, 222.92, 231.39, 190.14, and 183.33 µg/m3. Furthermore, BC concentrations ranged from 3.52 to 30.79 µg/m3. The heavy metals, including Pb, Fe, and Zn, were detected at maximum concentrations of 7.46 µg/m3, 1.67 µg/m3, and 9.77 µg/m3, respectively. Reconstructed PM analysis indicated that smoke mass accounted for the dominant fraction of the measured mass, ranging from 26.72 to 233.97 µg/m3, followed by soil-derived particles (0.93-22.39 µg/m3) and sea salt aerosols (0.22-7.50 µg/m3). Relative humidity was the principal meteorological predictor, explaining up to 48% of PM10 variability. Health-risk assessment indicated substantially greater exposure in the academic environment, with PM2.5 yielding an HQ of 22.29 under the WHO-based assessment, whereas estimated ILTCR values were 6.50×10-7 for PM2.5 and 1.31×10-6 for PM10. This study highlights the urgent need for stricter air quality management in Dhaka through stronger emission regulations, better traffic and dust control, cleaner resources and environment, sustainable urban planning, and targeted public health.

Institutions

• Bangladesh Atomic Energy Commission

  Dhaka Division, Dhaka
• University of Dhaka

  Dhaka Division, Dhaka

Categories

Licence