Global Prevalence of Legacy and Emerging Per- and Polyfluoroalkyl Substances in Estuarine Waters: Spatiotemporal Distribution, Trends, Drivers, and Risks

Per- and polyfluoroalkyl substances (PFAS), as persistent organic pollutants, accumulate in estuarine environments and pose serious threats to ecosystems and human health. This study compiled global data on PFAS contamination in estuarine waters and systematically analyzed their spatiotemporal distribution, temporal trends, socioeconomic drivers, and ecological risks. Results indicated that PFAS were ubiquitously detected in estuaries worldwide, with contamination hotspots identified in North America, Western Europe, and East Asia. Dominant compounds included perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorohexanesulfonic acid (PFHxS), and perfluorobutanesulfonic acid (PFBS). Those PFAS, predominantly composed of traditional groups such as perfluorocarboxylic acids (PFCAs) and perfluoroalkyl sulfonate acids (PFSAs), exhibited an inverted U-shaped temporal trend in concentrations with a fitted peak around 2015–2017. Partial least-squares path modeling (PLS–PM) revealed that industrial activity was the primary driver of PFAS contamination, whereas effective environmental governance directly mitigated pollution and positively influenced public health outcomes and demographic structure. Additionally, PFOA and PFOS remained the major contributors to ecological risks, while emerging concerns were identified for short-chain alternatives, such as perfluorobutanoic acid (PFBA) and PFBS. These findings highlight the urgent need for coordinated global governance and targeted interventions to mitigate ongoing PFAS pollution and address the potential risks posed by both legacy and alternative PFAS.