Particulate matter exposure to street vendors in Dhaka city and associated health risk study

Air pollution is a serious environmental health issue, particularly in heavily polluted urban areas such as Dhaka, Bangladesh. Street vendors, who often work in outdoor environments with high traffic emissions, are among the most vulnerable populations to particulate matter (PM) exposure. This study aims to evaluate the exposure of high-level PM_2.5 to twenty street vendors across various locations in Dhaka and to assess the consequent health impacts. AS-LUNG air sensors were utilized to continually measure PM exposure for each vendor for about 48 h, covering both work and rest periods. The data obtained demonstrated that the exposure levels of PM were significantly different among the vendors in various locations. The High Court corner exhibited the highest working period exposure (PM_1.0 143.3 ± 64.9 µgm⁻³, PM_2.5 247.4 ± 126.5 µgm⁻³), while the Chankharpol area had the lowest (PM_1.0 20.8 ± 1.9 µgm⁻³, PM_2.5 31.9 ± 3.1 µgm⁻³). The highest exposure was observed in vendor-10 during rest periods (PM_1.0 59.7 ± 4.8 µgm⁻³, PM_2.5 191.4 ± 9.7 µgm⁻³), while the lowest was observed in vendor-12 (PM_1.0 23.7 ± 5.7 µgm⁻³, PM_2.5 37.7 ± 9.9 µgm⁻³). In comparison to vendors exposed to lower levels (< 100 µgm⁻³), health assessments revealed that peak flow rates were considerably lower (p < 0.05) in those exposed to higher PM levels (> 100 µgm⁻³). PM exposure was consistently higher during work periods than during rest periods, despite significant indoor exposure was also observed. The findings emphasize the urgent need for guidelines and policies to mitigate PM exposure among street vendors, thereby minimizing associated health risks.