Fate and spatial variations of polybrominated diphenyl ethers in the deposition within a heavily urbanized area: case of Paris (France)

摘要

In this paper, we present the first results on the geochemical cycle of PolyBrominated DiphenylnEthers (or PBDE) in the Paris Region (France). In order to provide information about thendistribution and mobility of eight PBDE congeners, we first determined the level of contaminationnof different environmental compartments: i.e. atmosphere, soils and waters. Atmospheric PBDEndeposition was estimated from a site located in the centre of Paris. Surface soils (0–10 cm) werencollected from multiple wooded, rural and urban locations through the Paris Region (12,000 km2n).nTo complete our investigation, we measured PBDE concentrations/contents in the runoff from annurban catchment and settleable particles from the Seine River. Hence, gained results showed thatnin the superficial soils, the highest concentrations of highly brominated congeners werenmeasured in the vicinity of the most urbanized areas whereas less brominated congeners werenwidespread in the whole Paris Region. This could be explained by the higher affinity of highlynbrominated congeners for the solid phase substrata coupled with the fact that the atmosphericndeposition occurred mainly through particle deposition (close to 90% of the total atmosphericndeposition). To the opposite, the less brominated congeners from the superficial soils werenreadily transferred to the dissolved phase of runoff and could reach more distant terrestrial andnaquatic systems. Finally, a mass transfer was established at the scale of the Paris metropolitanncity (105 km2n). It showed that the cycle of PBDE in this particular urban area is highly dynamicnwith multiple sources and sinks, and rapid transfers between the ecosystem compartments.