Poly- and perfluoroalkyl substances (PFAS) pollution in South Korean water systems: A critical review of occurrence patterns and regulatory gaps

Per- and polyfluoroalkyl substances (PFAS) pollution in South Korean water systems is emerging environmental and public health concern, yet nationwide assessments remain limited. This review systematic evaluates PFAS occurrence across South Korea's primary water bodies and wastewater treatment plants (WWTPs), integrating historical and recent datasets from 49 facilities. Surface water monitoring (2004-2006) revealed widespread contamination, with 1.3-45.2 ng/L for PFOS and 2.9-19.7 ng/L for PFOA, particularly in the Hangang and Nakdonggang rivers, where downstream gradients reached ~40 ng/L (PFOA) and 38-59 ng/L (PFOS). Temporal analysis demonstrated a compositional shift from legacy long-chain PFAS (2006) to short-chain alternatives (2023-2024), reflecting regulatory-driven industrial transitions. WWTP analysis (2010) revealed industrial facilities consistently exceeded domestic counterparts, with PFOS reaching 829.44 ± 1837.41 ng/L in electronics manufacturing, of which data, collected in 2010, may not fully reflect the current situation. Conventional treatment proved ineffective, as effluent concentrations being 84-191% of influent levels. Current South Korean guidelines list only some PFAS as monitoring substances, with outdated values (70 ng/L for PFOA and PFOS) compared to stricter global standards. These findings highlight widespread PFAS detection and a critical regulatory gap, underscoring the urgent need for enforceable standards and advanced treatment technologies to support effective PFAS management.