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Bangladesh is one of the most populated countries in the world. Rapid industrialization and urbanization in the last decades have caused emission of pollutants in the environment. The aim of the study was to assess atmospheric 16 polycyclic aromatic hydrocarbons (Σ 16 PAH) in Bangladesh using PUF-PASs deployed in 5 metropolitan cities and one large non-metropolitan city from December 2017 to September 2018. Spatial distribution of Σ 16 PAH ranged from 3.6 ± 1.1 to 22.4 ± 6.9 ng/m3. The maximum concentration of 22.4 ± 6.69 ng/m3 was found on the site-23 (urban), a newly established metropolitan city. Reasonably, the lowest concentration (3.6 ± 1.1 ng/m3) was recorded at the rural site (site-7). Seasonal variation of ∑ 16 PAH was found to be 4.8–28.4, 2.2–12.0 and 2.7–30.5 ng/m3 in the winter, pre-monsoon and monsoon, respectively. Among the PAH isomers, phenanthrene, fluoranthene and pyrene significantly contributed to the total concentrations of PAHs with 30.4, 27.8 and 20.1% in the winter, 18.9, 29.4 and 21.9% in pre-monsoon and 14.2, 29.9 and 21.9% in monsoon, respectively. Seasonal variation of PAHs followed the decreasing order: winter > monsoon > pre-monsoon. Molecular weight-based results revealed that 4- and 3-rings PAHs (4-rings: 53–60%; 3-rings: 23–37%) mostly contributed to the total concentration of PAHs. Diagnostic ratios, PMF model and PCA results suggested that combustion of coal, petroleum, and incineration of biomass/plastics and municipal solid waste are the primary sources of PAHs in Bangladesh. Calculated BaP TEQ and BaP MEQ and ICR values were higher for the children than that of the adults. The higher values of the BaP TEQ and BaP MEQ and ICR compared to those suggested by the WHO and USEPA, imply that population of Bangladesh, particularly children, may be at high risk for health problems from PAHs. [Display omitted] • Monitoring of atmospheric PAHs using PUF-PASs in 6 metropolitan cities in Bangladesh. • High-way, urban, biomass-based combustion, dumping sites were highly contaminated. • Seasonal variation of PAHs follows decreasing order: winter > monsoon > pre-monsoon. • Combustion of coal, petroleum, biomass and municipal waste possible sources of PAHs. • Risk assessment shows high potential health risk caused by PAHs. [ABSTRACT FROM AUTHOR]