Status of Air Quality and Associated Health Risks in Dhaka Metropolitan City, Bangladesh: A Cold Wave Period Analysis

One of the most serious environmental problems in Dhaka Metropolitan City is air pollution due to uncontrolled vehicle, construction work, emission from surrounding industries and brick kilns and disappearing green space and water bodies. This study was performed to observe the levels of PM_2.5 and PM₁₀ in various areas of Dhaka Metropolitan City. hand-held Air quality monitor (Model: Aeroqual S500) used to collect data from 77 major road junctions during cold-wave of winter 2025.

The results show that the average levels of PM_2.5 and PM₁₀ concentration over the 77 sites were 211.16 µg/m³ and 277.82 µg/m³, respectively much higher than the Bangladesh National Ambient Air Quality Standards (65 µg/m³ for PM_2.5 and 150 µg/m³ for PM₁₀) increased by 3.25 and 1.81 times respectively. By zones, particulate concentration was highest in Zone-6 (Gulshan), followed by Zone-3 (Uttara), Zone-5 (Mirpur), Zone-7 (Tejgaon), Zone-2 (Motijheel), zone 1(Ramna) and next higher in category of particulate concentration was found in zone 4 (Lalbagh). The PM_2.5/PM₁₀ ratio suggested a predominance of combustion sources in total particulate mass (75.97 %). The dispersion analysis and box-whisker plots exhibit that the higher deviation was observed in Zone-2, whereas statistical tests to assess the difference among zones revealed no significant differences between the four zones for PM₁₀ (p > 0.05), with exception of PM_2.5. Cluster analysis also revealed the presence of four main clusters that converged at 25.

This elevated particulate level is a serious health hazard. PM_2.5 which can travel deep into the lungs and bloodstream is associated with respiratory infections, asthma, COPD, heart disease and premature death. PM₁₀ leads to decreased lung function, respiratory discomfort, and cardiovascular burden. The study suggests that Improved vehicle regulation, better construction management, cleaner industrial strategies along with more public transportation and public knowledge are require to minimize the health detriment in DHK as well as air quality enhancement.

Keyword: Air Pollution, Particulate Matter (PM_2.5 and PM₁₀), Dhaka City, Spatial Variation, Health Impacts