<p>Polycyclic aromatic hydrocarbons (PAHs) can pose a severe threat to public health. This study intends to evaluate the characteristics of fine particles (FP) and FP-bound PAH, their seasonal fluctuations, origins and health risk implications of PAHs in the urban area of Greater Ciro (GC) The results showed significant variation over the year in FP and ∑PAHs concentration, 56.2µg/m³ and 2195ng/m³, respectively. FP and PAHs levels exhibited similar seasonal fluctuations, with the highest concentrations during winter and the lowest during summer. High molecular weight—PAHs were the predominant in FP, representing 89.6% (spring) to 94.7% (summer) of the ∑PAHs. This study revealed notable positive associations between ∑PAHs and FP, while negative correlations were observed between PAHs and FP with ambient temperature. Molecular diagnostic ratios revealed that PAHs were locally emitted and primarily influenced by traffic emissions from liquid fossil fuel combustion (pyrogenic sources). FP-bound PAHs pose a moderate-high ecological risk. Based on the annual concentration of benzo(a)pyrene, it is anticipated that there would be a rise in the lifetime cancer risk by approximately 1600 cases per 100,000 individuals, beyond the limit designated by the WHO. FP-bound PAHs exhibited higher carcinogenic potential values compared to their mutagenic potential values. In assessing the PAHs health risk, the surrogate compounds DBA, BaP and BbF were employed. The health risk related to PAHs was highest during winter and lowest during summer. The incremental lifetime cancer risks (ILCR_ing and ILCR_dermal) and total cancer risk (CR) associated with PAHs were found to be above the “safe limit” suggested by the USEPA (10^–4). This suggests a significant and elevated risk for the population of Dokki urban area. This study represents the first comprehensive assessment in GC area (which is one of the largest mega-cities in the world) that integrates molecular diagnostic techniques with both ecological and human health risk evaluations, providing essential insight for air quality management in urban environments.</p> Graphical Abstract <p><i>Health risk assessment (HRA) of FP-bound PAHs (top and bottom left)</i> These plots has been created using adopted the USEPA standard models and the measurement data to evaluate human health risks via three main exposure pathways: ingestion, inhalation and dermal contact, reflecting the concept and scope of the work. The incremental lifetime cancer risk (ILCR) for PAH compounds was calculated by the summation of the individual ILCR estimated from all three exposure routes. For total PAHs, cancer risk was calculated through summation of the individual PAH cancer risks, applying three exposure routes.<i> Characteristic of FP-PAHs (top and bottom middle)</i> These three plots illustrate the levels, profiles and distribution of FP-PAHs in the atmosphere of the study area over the duration of the study based on the concentrations of the individual PAH compounds, aromatic ring numbers and ƩPAHs, reflecting the concept and scope of the work.<i> Source apportionments of FP-bound PAHs (top and bottom right)</i> These two plots were created, using the molecular diagnostic ratios (MDRs) of the parent measured FP-PAHs over the study period, to identify PAH sources and distinguishing between petrogenic and pyrogenic sources of PAHs in the atmosphere, reflecting the concept and scope of the work</p> <p></p>