Per- and polyfluoroalkyl substances in China's wastewater, surface water, and groundwater: occurrence
Qinru Wang1, Rui Qiu2, Yang Chen1
1State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering, College of Architecture and Environment, Sichuan University, Chengdu, 610065, China.
Abstract:
Per- and polyfluoroalkyl substances (PFAS) have aroused increasing concern in diverse environmental media owing to their ubiquitous occurrence. Understanding the relationships between various PFAS and relevant geographical areas necessitates an analysis of their spatiotemporal distribution and potential risk across different water systems. This study systematically analyzed the monitoring data of twelve PFAS in wastewater, surface water, and groundwater over the past two decades. The results indicated that wastewater treatment plants were a critical node for PFAS entering the environment, and their effluents led to similar PFAS distributions in surface and groundwater. Among the three water environments, perfluorobutyric acid, perfluorobutane sulfonate, and perfluorooctanoic acid (PFOA) exhibited consistently higher average concentrations. Of these, PFBA displayed the highest cross-media mean concentration, reaching 4666.92 ng/L. Linear mixed effects models revealed that concentrations of most PFAS have exhibited an increasing trend over time in wastewater, surface water, and groundwater. However, perfluoroundecanoic acid and perfluorododecanoic acid in wastewater treatment plant influent, and PFOS in surface water, trended downward. PFAS concentrations exhibited spatial heterogeneity, with higher levels in coastal areas, particularly in Jiangsu and Shandong Provinces. PFAS profiles varied by city, dominated by PFOA and short-chain PFAS, and related to fluorine chemical plant distribution. PFOS and PFOA had the lowest predicted no-effect concentrations (1330 and 3730 ng/L), indicating "medium" to "high" ecological risks in cities like Fuxin and Zibo. Under high drinking water exposure, these two compounds may pose adverse effects on human health. This study provided a basis for the control and management of regional PFAS pollution. It was suggested to develop a cross-media, multi-level monitoring and assessment system targeting key PFAS compounds.
