Lead Pollution Remanence in an Urban River System: A multi-scale temporal and spatial study

¹ Laboratoire des Sciences du Climat et de l’Environnement (LSCE/IPSL), UMR 1572 (CEA/CNRS/UVSQ), Domaine du CNRS, Avenue de la Terrasse, bat 12, 91198 Gif-sur-Yvette, FRANCE
² Interactions et Dynamique des environnements de Surface (IDES), UMR 8148 (UPS - CNRS), Bâtiment 504, Campus universitaire d’Orsay, 91405 Orsay Cedex, France
³ Civil Engineering Department, Engineering Faculty, Universitas Indonesia, UI Depok Campus, Depok 16424 – INDONESIA

^a sophie.ayrault@lsce.ipsl.fr
^b pierre.le-pape@u-psud.fr
^c cindy.priadi@eng.ui.ac.id

Abstract

This work aims at studying the fate of sediments contaminated with tetraethyl Pb from leaded gasoline using a two-dimension upscaling approach, from a small urban subcatchment, the Orge River (900 km²) to the whole Seine River basin (64700 km²), in France. In France, the leaded gasoline reduction started in 1986 and leaded gasoline was completely banned after 2000. This work aims at assessing whether the ban of leaded gasoline is related to changes in Pb contamination sources of these river suspended sediment particles (SPM) and bed sediment. Sediment cores and samples collected in the course of previous research projects of the Seine River contamination were used as temporal archives. The study of the isotopic lead ratio showed the fast decrease of the contamination of urban river suspended particulate matter due to the “gasoline” lead source from 2000 to 2011. This source mostly disappeared in the SPM from the Seine River basin that includes urban areas but also agricultural and industrial activities. Nevertheless, it is still present in the small urban catchment of the Orge River. The results on bed sediments showed a different pattern, where the “gasoline” source is still active in densely populated areas, either in the Seine River in the 20 km downstream Paris, or along the Orge River.