Persistent toxic substance inputs to the river Seine basin (France) via atmospheric deposition and urban sludge application.

Paris constitutes a major direct and indirect source of persistent toxic substances (PTS) to the river Seine, its tributaries and its basin, by atmospheric depositions and sewage sludge land-filling. The contaminant cycle and transfer pathways were investigated from 1999 to 2003 at local and inter regional scales in order to determine the respective importance of the main input and diffusion processes (wastewater, rainwater and runoff) from urban to rural areas. Paris constitutes an atmospheric emission hot spot for PAHs and PCBs. For example, for 2002, atmospheric concentrations ranged from 0.5 to 3 ng m(-3) for PAHs (Sigma 6 WHO) and from 0.06 to 0.69 ng m(-3) for PCBs (Sigma 7, EEC) and concentrations in bulk deposition ranged from 6.6 to 647 ng L(-1) for PAHs (Sigma 14) and from 0.6 to 8.1 ng L(-1) for PCBs. At Paris, annual atmospheric deposition inputs of PAHs (Sigma 6) and PCBs (Sigma 7) reached 104 g km(-2) and 35 g km(-2), respectively. PAHs followed a marked seasonal cycle in relation with winter domestic heating and bulk deposition concentrations were 5 to 15 times lower in remote areas. No seasonal cycle was observed for PCBs which varied little according to the area considered. PCB deposition fluxes were ruled by the rainfall amount, while for PAHs, the fluxes depended on local anthropogenic characteristics. At the scale of the Seine-Aval treatment plant comparison of annual inputs of PTS in wet period indicated that PCBs essentially come from atmospheric sources whereas PAHs are derived from both atmospheric and urban runoff sources. At the scale of the sub-basin, atmospheric inputs to the soil (Sigma 3 PAHs: 14-25 g km(-2), Sigma 7 PCBs: 5.6-25 g km(-2)) represent the prevailing source for PAHs and PCBs, as compared to that from the disposal of urban sludge on agricultural plots (Sigma 3 PAHs: 3-8 g km(-2), Sigma 7 PCBs: 0.5-2 g km(-2)).

Mass balance for polycyclic aromatic hydrocarbons in the urban watershed of Le Havre (France): transport and fate of PAHs from the atmosphere to the outlet.

Polycyclic aromatic hydrocarbon (PAH) concentrations have been monitored simultaneously in ambient air, bulk atmospheric deposition and runoff waters during one year in a small urban watershed of the Seine river basin (France). PAH fluxes from the atmosphere to the outlet of the urban watershed have been calculated to establish a mass balance for PAHs. PAH flux in runoff waters was 5.2 kg km(-2) yr(-1) while PAH atmospheric deposition was 0.21 kg km(-2) yr(-1). The comparison between atmospheric input and output by runoff has shown the importance of street deposits that appeared to be the most important source of PAHs for surface waters in urban areas. PAH profiles in the various compartments showed the fate of PAHs in the air-water system: proportion of carcinogenic PAHs was more important in runoff waters (35%) than in bulk atmospheric deposition (22%) and air (6%).

Distribution and spatial trends of PAHs and PCBs in soils in the Seine River basin, France.

Persistent organic pollutants (PAHs and PCBs) in soil samples from seven sites across the Seine basin were analysed. Samples were taken from industrialized, urban, suburban and remote sites. Results showed spatial differences, in terms of concentrations and congener profiles. PAH (Sigma14 PAHs) and PCB (Sigma 7 PCBs) concentrations ranged from 450 to 5650 microg kg(-1) and 0.09 to 150 microg kg(-1), respectively. A clear gradient from industrial to remote sites was highlighted, with a ratio of up to one order of magnitude for PAHs and two orders of magnitude for PCBs. Fluoranthene and pyrene were predominant, while the carcinogenic PAHs represented 15-46% of the total PAH content. Using hierarchical cluster analysis, soil samples profiles were compared and the influence of site location and potential sources were identified: automobile traffic, domestic heating, and industrial emissions were the prevalent PAHs sources in the Seine basin. PCB profiles suggested different transport patterns among congeners. For remote sites, the congener fingerprint showed a relatively higher proportion of the most volatile congeners, which were attributed to increased atmospheric residence times. Thus, PAH and PCB distributions in soils provided information on sources and evidence for short-range transport, and profiles of compounds reflected differences between regional and local emissions. This study demonstrates that soil sampling can be used to investigate spatial differences in atmospheric inputs of persistent organic pollutants based on differences in the mixtures of compounds, reflecting differences in regional and local atmospheric emissions.

Origin and distribution of polyaromatic hydrocarbons and polychlorobiphenyls in urban effluents to wastewater treatment plants of the Paris area (France).

Polyaromatic hydrocarbons (PAHs) and polychlorobiphenyls (PCBs), were investigated in urban effluents to wastewater treatment plants in the Paris area (France), under different meteorological conditions. The Achères plant was considered with special attention because of its particular features. Wastewater PAH concentration level was 6 fold higher than that of PCBs. In March, PCB concentrations did not vary whatever the meteorological conditions whereas, for PAHs, they were markedly higher during rainy episodes. In September, concentrations of both pollutants increased due to rainy weather. The rise was 30 fold stronger for PAHs. Daily fluxes displayed the same trends. This suggests that the contribution of atmospheric wet deposition to wastewater contamination prevails for PCBs. In contrast, PAHs appeared to originate mainly from urban runoff processes.

PCB and PAH impacts on cytochrome P-450-dependent oxidases in roach (Rutilus rutilus) from the Seine River (France).

Roach were sampled in the Seine River along a gradient of polyaromatic hydrocarbon (PAH) concentrations at three stations: Marnay upstream of Paris and Epinay and Poses downstream of Paris. Two hepatic monooxygenase activities: EROD (ethoxyresorufine-O-deethylase) and AE (aldrin epoxydase) and muscle residues of PCBs and PAHs were investigated during three periods of the year (before spawning, during spawning, and postspawning). Before spawning, EROD and AE activities were significantly correlated with muscle PCB levels (p