Between 2012 and 2013, 91 surface sediment samples were taken in the Loire River and tributaries. The aim of this extensive spatial survey was to characterize distinct geochemical signatures associated with specific anthropogenic activities and/or geogenic backgrounds in monolithological headwaters. Analyses focused on major and trace elements compositions (heavy metals and metalloids), all conducted using the same analytical procedures at the French National Centre for Scientific Research (CNRS) SARM-CRPG facilities (Nancy, France; https://sarm.cnrs.fr). In addition, total and organic carbon, grain-size and 137Cs measurements were carried out at the GéHCO research unit (University of Tours) and at the LSCSE research unit (CEA-CNRS-UNSQ) respectively.

Values with #0.00 are below detection limit, empty values are not measured