Source-oriented probabilistic risk assessment of polycyclic aromatic hydrocarbons in coal-mining streams: Coupling Monte Carlo simulation, positive matrix factorization, and risk models

in the dry and wet seasons, respectively. PAHs in Kuye River were primarily influenced by coking/petroleum, coal combustion, traffic emissions, and fuel-wood burning, contributing 37.39%, 34.78%, 14.40%, and 13.44%, respectively, to total concentrations. Ecological risks associated with these source-specific PAHs were classified as moderate, mainly attributed to BaA derived from coal combustion sources. Non-carcinogenic risks for all population groups were within safe limits based on the USEPA hazard quotient threshold. In contrast, under conservative exposure assumptions, the average total carcinogenic risks for all six population groups associated with source-specific PAHs exceeded the USEPA acceptable risk level, with a relatively high probability of risk exceedance. Females aged 2 -15 years showed the highest estimated risks, and dermal exposure was estimated as the primary pathway. In addition, traffic emission sources and BaP were inferred as potential priorities for controlling carcinogenic risks. These results are screening-level estimates based on default parameters and require validation using local data. The findings highlight the importance of probabilistic risk assessment methods based on specific pollution sources and provide a scientific basis for comprehensive PAH risk assessment and prevention strategies in coal mining areas.