Per- and polyfluoroalkyl substances (PFAS) are chemicals of emerging concern that potentially pose risks to human and environmental health. In May–Oct 2018, sediment and passively collected surface water samples were collected from 62 tributary sites of the Laurentian Great Lakes with site catchments spanning gradients in land cover. Discrete samples of sediment and time-integrated surface water samples collected with polar organic chemical integrative samplers (POCIS) were analyzed for 23 and 34 PFAS, respectively. Concentrations of individual PFAS in sediment and surface water varied substantially among sites from below detection to 20,800 ng kg-1 and 247 ng L-1, respectively. Elevated PFAS concentrations occurred in urban watersheds and downstream of airports and wastewater treatment plants (WWTP). Of all target compounds, PFOS was the most frequently detected in sediment (56 of 62 sites) and had the highest median concentration (132 ng kg-1). PFOA, PFHxS, PFOS, PFHpA, and PFNA were detected in all 60 surface water sites, with median concentrations of 5.9, 5.2, 4.6, 3.7, and 1.3 ng L-1, respectively. Compounds with 8–14 fluorocarbons comprised a larger proportion of sediment PFAS than compounds with 4–7 fluorocarbons, whereas compounds with 4–7 fluorocarbons were dominant in surface waters. Watershed attributes, including urban land cover and WWTP flow fraction were positively related with PFAS sum concentrations in sediment and surface water. Collectively, these results highlight the relation PFAS occurrence has with human activities and documents widespread low-level PFAS contamination across the Great Lakes basin. This dataset is associated with the following publication: Loken LC, Corsi SR, Alvarez DA, Pronschinske MA, Lenaker PL, Nott M, Zhang C, Mani E, Ankley GT. Per- and polyfluoroalkyl substances (PFAS) in surface water and sediment in Great Lakes tributaries and relations with watershed attributes. In Review. This dataset is not publicly accessible because: It is inconsistent with established Federal practices for EPA to be the repository of data generated by the USGS. It can be accessed through the following means: All data will be completely accessible through the USGS and detailed instructions for its access will be described in the peer-reviewed journal article. Format: The data were generated by the US Geological Survey (USGS) who, like EPA, are required to make all their data publicly available through their open access website concurrent with publication of a paper. When this occurs, the data will be in a standard format, e.g., as spreadsheets with accompanying metadata.

This dataset is associated with the following publication: Loken, L., S. Corsi, D. Alvarez, M. Pronschinske, P. Lenaker, M. Nott, C. Zhang, E. Mani, and G. Ankley. Per- and polyfluoroalkyl substances in surface water and sediment in Great Lakes tributaries and relations with watershed attributes. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 44(6): 1503-1524, (2025).