9 This study investigates the occurrence of all priority substances (n = 41) listed in the 10 Water Framework Directive and additional substances (n = 47) in raw sewage, as well as the 11 removal performance of lamella clarification and biofiltration techniques. Once the efficiency 12 of both types of techniques has been assessed for typical wastewater parameters, the

This paper investigates the occurrence of alkylphenols (APs) and polybromodiphenylethers (PBDEs) in raw wastewater during dry and wet-weather periods, and their removal by physico-chemical lamellar settling and biofiltration techniques. Due to in-sewer deposit erosion and, to a lesser extent, to external inputs, raw effluents exhibit from 1.5 to 5 times higher AP and PBDE concentrations during wet periods compared with dry ones. The lamellar settler obtains high removal of APs and PBDEs under both dry and wet-weather flows (>53% for Σ(6)AP and >89% for Σ(4)PBDE), confirming the insensitivity of this technique to varying influent conditions. Indeed, despite the higher pollutant concentrations observed in raw effluents under wet-weather flows, adjusting the addition of coagulant-flocculent allows for efficient removal. By combining physical and biological processes, the biofiltration unit treats nutrient pollution, as well as Σ(6)AP and Σ(4)PBDE contamination (58 ± 5% and 75 ± 6% respectively). Although the operating conditions of the biofiltration unit are modified during wet periods, the performance in nutrient pollution, APs and light PBDE congeners remains high. Nevertheless, lower efficiency has been noted in nitrogen pollution, i.e. no denitrification occurs, and BDE-209 (not removed during wet-weather periods). In conclusion, this study demonstrates that the combination of both techniques treats AP and PBDE pollution efficiently during dry periods, but that they are also suitable for stormwater treatment.

This work focused on alkylphenol ethoxylates (APEOs) and bisphenol A (BPA) in surface water at the scale of the upper part of the Seine basin. Although this basin is vulnerable, since it undergoes a combination of strong human pressures (Paris conurbation) with very limited dilution via the Seine River, no comprehensive data was available for these compounds. In this context, the evolution of the pollutant concentrations and loads was assessed during two sampling campaigns (April and July 2009) along a 300 km-transect. Hence, 18 stations (10 sites on the Seine River, four tributaries and four wastewater treatment plants -WWTPs) were considered. Additional campaigns were also conducted over 2009 on four sites on the Seine River. The BPA concentrations range from 7.2 to 127 ng.l -1 in surface water, while higher concentrations of APEOs (324 ± 153 ng.l -1 ) were observed. Based on our first results, no spatial variability of concentrations between up-and downstream sites, or any seasonal variability, were highlighted. During the longitudinal campaigns, an increase of the pollutant loads between up-and downstream sites was clearly noticed. Contrary to BPA, for which a limited seasonal variation of loads was observed at the basin outlet (1,400 and 1,500 g.d -1 ), the APEO loads significantly vary (10,000 and 5,500 g.d -1 ). Mass balances between the inputs (tributaries + WWTPs) and the exported loads reveal that the BPA inputs are lower than the exported loads, suggesting that other inputs have to be considered along the transect studied. For APEOs, the inputs appear higher than the exported loads, underscoring the in-stream removal of APEOs. Globally, the results reveal that the removal of APEOs and the number of ethoxylate units are correlated -the longer the ethoxylate chain, the higher the removal.