Model-based assessment of historical and future soil PAHs trends in China under divergent energy scenarios

China faces widespread soil contamination by polycyclic aromatic hydrocarbons (PAHs) due to rapid industrialization. However, the continuous spatiotemporal evolution of this contamination under shifting energy structures remains poorly quantified. To bridge this gap, we developed a machine learning framework to assess soil PAHs dynamics from 1980 to 2100, integrating 662 surveys with key environmental and socio-economic drivers. The assessment reveals that soil PAHs concentrations increased from 217.9 μg/kg in 1980 to 316.5 μg/kg in 2020, with fossil fuel combustion identified as the primary driver (62.0% contribution). Under divergent future scenarios, our model predicts that soil PAHs will continue to accumulate, reaching 427.2 μg/kg by 2100 under the baseline scenario. Notably, even under the ambitious 2 °C trajectory, the legacy effect leads to a prolonged accumulation phase, highlighting a significant "policy inertia" in soil environmental response. These findings provide a critical model-based foundation for long-term soil remediation and energy policy optimization in China.