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Highlights • PFOS and PFOA levels are suggestive of levels of industrialization and poor environmental awareness. • Concentrations of PFOS and PFOA in porewater were greater than those in surface water. • Results of this study provided additional understanding of PFOS and PFOA partitioning between sediment and porewater. • Field – based fate and partitioning of PFOS and PFOA were highly dependent on salinity gradients. • Adsorption of PFOS and PFOA can be greater than expected due salinity changes in aquatic environment. Abstract Global concern on emerging pollutants such as perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) are well documented. Unfortunately, information is either scarce or non-existing on the presence of these chemicals in most developing nations like Nigeria. The current study examined the distribution pattern and trend of PFOS and PFOA in surface water, porewater (PW) and sediments collected from three geopolitical zones with different levels of industrialization in Nigeria. PFOS and PFOA were concentrated using solid-phase extraction, identified and quantified by high performance liquid chromatography interfaced to a triple quadruple mass spectrometer. Detection of both PFOS and PFOA in all samples suggested wide distribution across Nigeria. Generally, PFOS dominated aqueous concentrations ranging from 3.9 to 10.1 ng L−1 in surface water, 10.9 to 20.4 ng L−1 in PW and 5.1 to 10.4 ng g−1 in bottom sediment. Field-based partition coefficients (K d) for both PFOS and PFOA were significantly correlated with salinity (r 2 = 0.84 and 0.78 respectively, p < 0.01); The K d values increased exponentially as a function of salinity. The enrichment of both PFOS and PFOA on sediment increased with increasing organic matter while in water with increasing salinity. The detection of these chemicals across all samples suggested urgent attention in their risk assessment. [ABSTRACT FROM AUTHOR]