Per-andpoly-fluoroalkylsubstancesinaquaticecosystemsandwastewater treatmentworksinAfrica:Occurrence,ecologicalimplications,and futureperspectives

Abstract

The increasing levels of industrialization and urbanization have led to the generation of significant amounts of wastewater and waste products, often containing chemicals like per- and poly-fluoroalkyl substances (PFASs) commonly found in consumer products. PFAS sare known for their persistence, ubiquity, and ecotoxicological impacts, raising concerns about potential harm to ecosystems. This paper reports the occurrence and evaluates the ecological risks of PFASs in aquatic ecosystems and wastewater treatment works (WWTWs) across Africa. We reviewed 32papers published in the period 2009–2024 and identified a total of 35 PFAS compounds in surface waters, wastewater,s ediments, fish, crocodiles, and invertebrates. Much of the reported studies came from South Africa, followed by Kenya and Nigeria. PFAS concentrations in Africa were<0.7–390.0ngL− 1 in surface waters, 0.05–772 ng g− 1 dw in sediments, and <0.2–832 ng L− 1 in wastewater, while the highest levels in fish and invertebrateswere460.7and35.5ngg− 1 ww, respectively. The PFAS levels were in the same range of data as those reported globally. However, the high concentrations of PFAS s in sediments and wastewater suggest are as of point contamination and a growing risk to aquatic ecosystems from effluent discharges. Calculated risk quotients suggested that, in Africa, organisms in river systems face greater risks due to exposure to PFASs compared to those in lakes, while marine organisms might facehig herrisk compared to freshwater organisms. Future studies should focus on PFAS contamination sources, especially WWTWs, as emerging sources of PFASs in aquatic systems.