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Implementation of the European Water Framework Directive 2000/60/EC (WFD) requires Member States to expand their collective knowledge of priority pollutants (PPs) within receiving waters. To achieve this objective, information on the occurrence of PPs in surface waters and, more specifically, within densely urbanized areas needs to be collected. This study has therefore been designed to provide information on both PP occurrence and concentration build-up along a heavily urbanized transect of the Seine River in the Paris region (France). A large range of PPs were observed in settleable particles and, to a lesser extent, in the waters surveyed. In surface waters, a total of 18 PPs, including 15 priority hazardous substances, were indeed detected, yet concentrations rarely exceeded the limit of quantification. In fact, only diuron, DEHP, fluoranthene and para-tert-octylphenol are observed on a frequent basis, with concentrations ranging from <0.01 to 1.0 microg l(-1). As regards the Environmental Quality Standards (EQS), 10 substances or groups of substances were found in surface waters to exhibit concentrations above the annual average value, while only the benzo(a)pyrene concentration exceed the maximum allowable level. As for the Canadian Sediment Quality Guidelines, settleable particles collected in the Seine River appear to be heavily contaminated since most samples contain PP levels above the guideline values (18 PPs) and, in many cases, above the probable effect levels (15 PPs), which underscores that the levels of metals, PAHs and PCBs in settleable particles constitute a potential risk to freshwater organisms.

Objective: The objective of this study was to evaluate our practices concerning difficult lesions sent for second opinion to an expert., Material and Methods: We analyzed retrospectively all the requests for second opinion carried out over one year in our laboratory. The following data were indexed: organ, pathology (tumoral or not), type of sampling, the time, additional techniques carried out by the expert and comparison of the initial diagnosis with that of the expert. A provisional report was systematically performed before sending the observation to the expert., Results: Among the 54 cases, 40 lesions were tumoral and 31 malignant. The type of pathology which were more often sent for opinion were lymphomas (18.5%) and soft tissue tumors (11%). The average time between reception of the sampling in our laboratory and the answer of the expert was 32.8 days. In 40.7% of the cases, additional techniques like immunohistochemistry (19 cases) or molecular biology (7 cases) were carried out by the expert and concerned especially lymphomas or soft tissue pathology. The comparison of the initial diagnosis with that of the expert showed no change in 53.7% of cases, 13% of divergence from benign-malignant (6 cases) or malignant-benign (1 case) type, 16.7% of changes of classification without modification of the benignity or the malignity, and 16.7% of difficult interpretation., Conclusion: This study seems to be a good means of evaluating our professional practices related to difficult lesions and confirms the importance of deep-freezing tumors, holding multidisciplinary meetings and participating in specialized working groups.

Total atmospheric deposition, i.e. both wet and dry ones, was sampled during three different sampling periods between 1994 and 2002. The aim of this study is to determine the temporal variation of the atmospheric deposition fluxes of four heavy metals (Cd, Cu, Pb and Zn) in an urban area (Paris region, France). The global pattern shows a decrease of the fluxes for most of elements during this period. Indeed, the atmospheric deposition fluxes measured in 2001-2002 were lower than those measured during the 1994-1997 period by factors reaching 16, 2.5, 4 and 7.5 at Créteil and 7, 1, 6 and 4.5 at Chatou for Cd, Cu, Pb and Zn, respectively. At the Paris site, the decreasing factors were 2.5 and 3 for Cd and Pb, respectively while Cu and Zn fluxes were nearly similar during the whole studied period.

Over a period of two years (2000-2001), sediment samples were extracted from 40 silt traps (STs) spread through the combined sewer system of Paris. All sediment samples were analysed for physico-chemical parameters (pH, organic matter content, grain size distribution), with total hydrocarbons (THs) and 16 polycyclic aromatic hydrocarbons (PAHs) selected from the priority list of the US-EPA. The two main objectives of the study were (1) to determine the hydrocarbon contamination levels in the sediments of the Paris combined sewer system and (2) to investigate the PAH fingerprints in order to assess their spatial variability and to elucidate the PAH origins. The results show that there is some important inter-site and intra-site variations in hydrocarbon contents. Despite this variability, TH and PAH contamination levels (50th percentile) in the Parisian sewer sediment are estimated at 530 and 18 microg g(-1), respectively. The investigation of the aromatic compound distributions in all of the 40 STs has underlined that there is, at the Paris sewer system scale, a homogeneous PAH background pollution. Moreover, the study of the PAH fingerprints, using specific ratios, suggests the predominance of a pyrolytic origin for those PAHs fixed to the sewer sediment.

Urban surface contamination, by atmospheric deposits as well as human activities, is a major concern for urban pollution management. Besides coarse street deposits which are clearly perceived and easily removed, suspended solid (SS) surface loads and contamination by heavy metals and hydrocarbons are rarely assessed although they could be of major importance with regards to combined or separate server overflow (CSO and SSO) impacts. Both dry and wet vacuum sampling procedures have been first compared, in the laboratory, using dry and sieved clay or street deposits. Then the wet vacuum sampling procedure has been refined, coupling the injection of water and the hand-brushing of the surface prior to its vacuum cleaning, and evaluated on a car parking area close to the University. Finally this procedure has been assessed in Béarn Street within the 'Le Marais' district in Paris centre, and 34 samples have been analysed for metal and eight for aromatic hydrocarbon contamination. Heavy metal concentrations (0.1-1.7 g kg-1 dry wt. Cu, 0.9-6.1 g kg-1 dry wt. Pb and 1.5-4.6 g kg-1 dry wt. Zn) within street deposit samples collected in Paris centre, indicate a high contamination, especially for copper and zinc, as compared to reported data. Total polyaromatic hydrocarbons (PAHs) are in the 3-11 mg kg-1 dry wt. range, thus approximately 10 times less contaminated than dry atmospheric deposits. This paper presents data obtained and discusses the difficulties encountered when sampling street deposits in busy areas of a city like Paris. The water jet street cleaning procedure used by Paris city workers was tested for its efficiency, by comparison of surface loads before and after the cleaning procedure. Although solids cleaning efficiency is highly variable (20-65%) and somewhat higher for particles larger than 100 microns, particulate metal cleaning efficiency is even more variable (0-75%) and particulate PAHs appear not to be significantly removed.