Mapping PFAS behavior via meta-analysis of soil dynamics, predictive modeling and policy integration

Per- and polyfluoroalkyl substances (PFAS) are persistent organic pollutants with increasing prevalence in agricultural soils, primarily introduced through biosolid application, wastewater irrigation, and atmospheric deposition. This review provides a meta-analysis of terminologies across 145 peer-reviewed studies, identifying inconsistency in the classification of PFAS subgroups-such as "long-chain vs. short-chain," "precursors," and "emerging PFAS"-which hinders regulatory harmonization and model calibration. Empirical data reveal PFAS leaching depths ranging from 3 cm in sandy soils under low irrigation (1500 ng/L) to 10 cm in clay under high irrigation (200 ng/L). Analytical advances, including LC-MS/MS and hyperspectral drone imaging, enable detection limits below 0.05 μg/kg and hotspot identification at 1 m spatial resolution. Modeling tools like HYDRUS, MODFLOW-MT3DMS, and CalTOX simulate PFAS transport, bioaccumulation, and degradation with increasing fidelity. Biochar application reduced PFOS leaching by >80 %, and plasma treatment achieved 95 % PFAS degradation within 2 h. A global policy comparison reveals fragmented regulatory frameworks: the U.S. EPA promotes voluntary monitoring and advisory levels (e.g., 4 ng/L for PFOA+PFOS in water), while the EU progresses toward enforceable soil thresholds and PFAS phase-outs under REACH. Austria's ÖNORM S 2088-2 integrates human, plant, and ecological endpoints, contrasting with the USDA's BMP (Best Management Practices)-driven mitigation. The review advocates for terminology standardization, integration of multi-model transport and fate simulations, and hybrid remediation strategies. Policy convergence, driven by data transparency and international scientific cooperation, is imperative to safeguard soil health, food safety, and ecological resilience in PFAS-impacted agroecosystems.