Anthropogenic Release of Per- and Polyfluoroalkyl Substances into Surface Water Systems: Distribution Characteristics and Environmental Persistence Analysis

In view of the issues including the incomplete identification of alternatives and difficulty in tracing pollution sources in PFAS pollution monitoring in surface water, this study took typical surface waters with intensive human activities as the object to perform PFAS screening. A nontarget analysis based on high-resolution mass spectrometry was developed, coupled with a modified solid phase extraction pretreatment method, to achieve the comprehensive screening of 12 legacy carboxylic acids and sulfonic acids, as well as 2 novel alternatives in water. Surface water samples were collected from typical functional areas of human activity to reveal the spatial differential distribution of PFAS concentrations. The long-chain PFASs showed a high detected concentration, among which PFOS, PFUnDA, and PFOA concentrations were especially high in urban complex pollution areas, while PFDA, PFOS, and PFOA were the main components in agricultural areas. The two exposure patterns showed a certain degree of differentiation, which may be related to different pollution sources. PFASs with a long carbon chain, especially chlorine-substituted sulfonic acid, are high-persistent-risk substances. This study provided the data basis for the prevention and control of PFAS pollution in surface water, and supported the treatment of emerging pollutants in the region.