Physico-chemical properties of sediment deposits of the March 2024 flooding of the Seine River, along with contamination in metals, pesticides, pharmaceuticals, drugs and lifestyle products

Sediment was collected on the quays along the Seine River across Paris City following the flood of March 2024. The objective was to measure a panel of potential contaminants in sediment deposited by the Seine River before the Paris 2024 Olympics. Fallout radionuclide (137Cs, 7Be, 210Pb) activities were analysed by gamma spectrometry using hyperpure germanium detectors at the Laboratoire des Sciences du Climat et de l’Environnement (LSCE, Paris-Saclay, France). Major, minor and trace elemental concentrations were analysed at the same laboratory with an Inductively Coupled Plasma – Mass Spectrometer equipped with 3 quadrupoles (TQ-ICP-MS, Thermo ScientificTM iCAPTM). Stable radiogenic lead isotope (206Pb, 207Pb, 208Pb) ratios were also determined (Briard et al., 2023). Particle size distribution was analysed with a laser diffraction particle size analyser (Mastersizer 3000 with Hydro LV, Malvern Panalytical) and Total Organic Carbon (TOC) was quantified using a Rock-Eval 6 equipment. Pharmaceutical products and pesticides were analysed following the protocol described by Thiebault et al. (2021), and lifestyle products following the methodology described by Bernier-Turpin et al. (2025). This dataset is described and interpreted in a manuscript submitted for publication in an international journal. References Bernier-Turpin, G., Moilleron, R., Cenik, C., Alliot, F., Guerin-Rechdaoui, S., Thiebault, T., 2025. Do suspended particles matter for wastewater-based epidemiology? Water Research, 280: 123543. Briard, J., Ayrault, S., Roy-Barman, M., Bordier, L., L'Heritier, M., Azema, A., Syvilay, D. and Baron, S., 2023. Determining the geochemical fingerprint of the lead fallout from the Notre-Dame de Paris fire: Lessons for a better discrimination of chemical signatures. Science of Total Environment, 864: 160676. Thiebault, T., Alliot, F., Berthe, T., Blanchoud, H., Petit, F., Guigon, E., 2021. Record of trace organic contaminants in a river sediment core: From historical wastewater management to historical use. Science of Total Environment, 773: 145694.