Effects of Dissolved Organic Matter (DOM) on Perfluorooctanoic Acid (PFOA) in a Seagoing River—A Case Study of the Wanggang River Flowing into the East China Sea

Perfluorooctanoic acid (PFOA) is an emerging environmental pollutant that has attracted widespread attention. In this study, water samples were collected from the Wanggang River in the eastern coastal area of China, and the PFOA and dissolved organic matter (DOM) levels were measured. The results show that the PFOA concentration in the water bodies ranges from 3.2 to 52.9 ng·L−1, and the average value is 27.1 ± 13.4 ng·L−1, indicating an intermediate level. Two protein-like (C2, C3) and two humus-like (C1, C4) DOM components in the Wanggang River are attributed to rainfall and human activities. Differences are observed in the DOM components before and after the flood season. The humus-like components are higher in the post-flood season, and are one of the factors affecting PFOA distribution and concentration in the Wanggang River. The results provide data support for monitoring and evaluating PFOA in rivers and help formulate PFOA pollution management strategies. In future research, it might be better to define the interaction between DOM and emerging organic pollutants by using 17 PFASs as subjects.