Trace, technology-critical, and rare earth element data from six boreal lakes near Rouyn-Noranda [Québec, Canada, 2019–2023]

Data were collected from six boreal lakes near Rouyn-Noranda, Québec, Canada, between 2019 and 2023. Lakes were selected along a gradient of contamination associated with historical mining and smelting activities, including the Horne Smelter (nearby, intermediate, and distant lakes). Water, sediments, and fish tissues (muscle and liver) were sampled to measure trace elements (TEs), technology-critical elements (TCEs), and rare earth elements (REEs). Water samples were collected from the epilimnion at multiple locations per lake, while sediment samples were taken from the top 2–3 cm of the lakebed. Fish (walleye and yellow perch) were captured using gillnets, and morphometric data were recorded before sampling liver and muscle tissues. Trace element concentrations were measured using triple quadrupole ICP-MS, and data were compared with Canadian environmental quality guidelines for water and sediment, as well as FAO/WHO guidelines for fish consumption. The purpose of the dataset is to evaluate how historical mining and e-waste recycling influence the spatial distribution of TEs, TCEs, and REEs across multiple environmental matrices, and to assess potential ecological and human health risks. A manuscript has been published in Science of the Total Environment (https://doi.org/10.1016/j.scitotenv.2025.180916 ).