Persistent organic pollutants versus their alternatives in the eastern Pearl River Estuary, South China: Distribution, ongoing transition, and risk prioritization

作者：Qi Wang, Yetong Shao, Linjie Jin, Shengchao Yao, Yutong Zhang, Naiyu Xie, Kendric A. Tee, Shaopeng Xu, Kmy Leung, Yuefei Ruan · 发表于：Environment International · 年份：2026 · DOI：10.1016/j.envint.2026.110447 · 研究领域：Toxic Organic Pollutants Impact、Marine and coastal ecosystems、Coastal wetland ecosystem dynamics

With the global restriction and phase-out of Persistent Organic Pollutants (POPs), environmental occurrence, fate, and risks of the widespread-use alternatives to POPs are gaining increasing global concern. This study provides a systematic assessment of three major groups of POPs and their alternatives, including 45 per- and polyfluoroalkyl substances (PFAS), 29 halogenated flame retardants (HFRs), and three classes of chlorinated paraffins (CPs, including short-chain CPs, medium-chain CPs, and long-chain CPs), in seawater and sediment from the coastal environment of the Hong Kong Special Administrative Region of China, a densely populated metropolis in the eastern Pearl River Estuary receiving substantial anthropogenic inputs. Concentrations of PFAS, HFRs, and CPs in seawater ranged 2.56-174, 1.29-81.4, and 39.2-361 ng/L, respectively, while those in sediment ranged 0.248-1.86, below the method quantification limit (<MQL)-107, and < MQL-120 ng/g dry weight (dw), respectively. Notably, three POP alternatives including perfluorobutanoate, medium-chain CPs, and 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine (TTBP-TAZ) predominated over legacy POPs in water, suggesting a potential ongoing transition. On the other hand, certain POPs like perfluorooctane sulfonate and polybrominated diphenyl ethers persisted in sediments at relatively low levels (<0.405 and <2.74 ng/g dw, respectively), reflecting their high environmental recalcitrance. While hazard quotients suggest POPs and th...