Nationwide monitoring of freely dissolved polycyclic aromatic hydrocarbons (PAHs) using high speed rotation-type passive sampling device in Korean coastal waters

Measuring the concentration of PAHs in the freely dissolved phase is crucial for assessing ecological impacts in the marine environment. However, various environmental conditions make short-term monitoring challenging. This study used an optimized High Speed Rotation-Type Passive Sampling Device (HSR-PSD) equipped with linear low-density polyethylene (LLDPE) to conduct the first nationwide monitoring of freely dissolved PAHs in Korean coastal waters. The HSR-PSD enabled faster short-term monitoring by measuring C_free of PAHs within 12 h and was less affected by environmental conditions compared to conventional PSDs. Σ₁₅PAH concentrations ranged from 2.8 to 9.4 ng/L, with significantly higher levels on the western coast. Anthropogenic activities and oceanic conditions affected C_free distribution in coastal areas. Based on C_free, the estimated PAH levels in bivalves and fish were aligned with reported tissue concentrations, exhibiting low ecological risk to aquatic organisms. Therefore, the HSR-PSD with LLDPE is a suitable tool for nationwide short-term monitoring.