In this paper, we present the first results on the geochemical cycle of PolyBrominated Diphenyl Ethers (or PBDE) in the Paris Region (France). In order to provide information about the distribution and mobility of eight PBDE congeners, we first determined the level of contamination of different environmental compartments: i.e. atmosphere, soils and waters. Atmospheric PBDE deposition was estimated from a site located in the centre of Paris. Surface soils (0–10 cm) were collected from multiple wooded, rural and urban locations through the Paris Region (12,000 km2). To complete our investigation, we measured PBDE concentrations/contents in the runoff from an urban catchment and settleable particles from the Seine River. Hence, gained results showed that in the superficial soils, the highest concentrations of highly brominated congeners were measured in the vicinity of the most urbanized areas whereas less brominated congeners were widespread in the whole Paris Region. This could be explained by the higher affinity of highly brominated congeners for the solid phase substrata coupled with the fact that the atmospheric deposition occurred mainly through particle deposition (close to 90% of the total atmospheric deposition). To the opposite, the less brominated congeners from the superficial soils were readily transferred to the dissolved phase of runoff and could reach more distant terrestrial and aquatic systems. Finally, a mass transfer was established at the scale of the Paris metropolitan city (105 km2). It showed that the cycle of PBDE in this particular urban area is highly dynamic with multiple sources and sinks, and rapid transfers between the ecosystem compartments.
Keywords: atmospheric deposition, Paris Region, PBDE, soil contamination, surface waters, transfer