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Numerous ecological risk assessment methodologies have been developed over the last twenty years around the world for evaluating urban and industrial systems and installations, by both the organisations responsible for implementing regulations and the scientific community. Although these methodologies share the general principle underlying their use, they differ widely with respect to the approaches chosen and the resources employed to apply them. Also, they may even have different objectives: prior assessment as part of an impact study before building a new installation, or retrospective assessment, for example, in view to explaining the reasons for an impact recorded or for forecasting additional expected impacts. This article provides a synthesis of the different approaches used around the world for carrying out each of the major steps common to all ecological risk assessment methodologies. The advantages and limitations of these different options are discussed in order to provide elements for formulating any new methodology adapted to a given scenario. To conclude, perspectives for improving the tools required for these methodologies are proposed, and the research works to which priority should be given are identified.

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Hospital effluents cause environmental problems since they are 5-15 more toxic than urban effluents and they are not subjected to any pre-treatment before being discharged into urban sewage networks. The hypothesis used to explain this toxicity is the presence of disinfectants and detergents. This study is aimed at highlighting the ecotoxicity of a peracetic acid-based disinfectant to Daphnia magna, as well as the combined effects of this disinfectant in binary mixtures with three types of detergent. The detergents used here are: cetyltrimethylammonium bromide (CTAB, cationic), sodium dodecylsulfate (SDS, anionic) and Triton X-100 (TX, non-ionic). The toxicity of the mixtures is studied as a function of five predefined ratios. At the end of the study, we conclude that peracetic acid seems to be slightly toxic to Daphnia magna. Indeed, the efficient concentration inhibiting the mobility of 50% of the population of Daphnia at 24 h (EC50) is 116.6 mg/l. Globally, additive effects are observed for all the binary peracetic acid-detergent mixtures. However, for the peracetic acid-TX mixture, its effects have antagonistic tendencies whereas the peracetic acid-CTAB mixture has slight synergic tendencies. The mixture containing peracetic acid and SDS is slightly antagonistic for ratios containing more than 50% peracetic acid.

Environmental field studies have shown that carbamazepine (Cbz) is one of the most frequently detected human pharmaceuticals in different aquatic compartments. However, little data is available on the detection of this substance and its transformation products in aquatic organisms. This study was thus mainly carried out to optimize and validate a simple and sensitive analytical methodology for the detection, characterization and quantification of Cbz and oxcarbazepine (Ox), two anticonvulsants, and six of their main transformation products in marine mussels (Mytilus galloprovincialis). A modified QuEChERS extraction method followed by analysis with liquid chromatography coupled to high resolution mass spectrometry (HRMS) was used. The analyses were performed using two-stage fragmentation to reveal the different fragmentation pathways that are highly useful for the identification of isomeric compounds, a common problem when several transformation products are analyzed. The developed analytical method allowed determination of the target analytes in the lower ng/g concentration levels. The mean recovery ranged from 67 to 110%. The relative standard deviation was under 11% in the intra-day and 18% in the inter-day analyses, respectively. Finally, the method was applied to marine mussel samples collected from Mediterranean Sea cultures in southeastern France. Residues of the psychiatric drug Cbz were occasionally found at levels up to 3.5ng/g dw. Lastly, in this study, other non-target compounds, such as caffeine, metoprolol, cotinine and ketoprofen, were identified in the real samples analyzed.

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Increasing phosphorus (P) content and decreasing water quality of Saint-Augustin Lake, Quebec City, Canada, has led to implementation of an Integrated Watershed Management Plan to restore the lake. As a part of the plan, the effects of different restoration techniques on lake water quality and biological community (i.e., biological compatibility) were assessed during an isolated water enclosure study and laboratory microcosm assay, respectively. The restoration techniques include: (i) coagulation of P by alum only (20 mg L(-1)), (ii) active capping of sediments using a calcite layer of 10 cm, and (iii) a complete method involving both alum coagulation and calcite capping. The results showed that the total P (TP) was greatly decreased (76-95 %) by alum + calcite, followed by calcite only (59-84 %). Secchi depth was 106 % greater and chlorophyll a concentrations were declined by 19-78 % in the enclosure which received both alum and calcite. Results of the biological compatibility test showed that total phytoplankton biomass declined by 31 % in microcosms composed of alum + calcite. No significant (P> 0.05) toxic effect was found on the survival of Daphnia magna and Hyalella azteca in both alum only and alum + calcite microcosms. Although the alum + calcite technique impaired the survival of Chironomus riparius, the midge emergence was much higher compared to alum only and control. Overall, the alum + calcite application was effective in controlling P release from sediment and lowering water column P concentrations, and thus improving the water quality and aquatic life of Saint-Augustin Lake. However, the TP concentrations are still higher than the critical limit (20 μg L(-1)) for aquatic life and the water column remained in the eutrophic state even after treatment. Increased TP concentrations, to higher than ambient levels of the lake, in the water column of all four enclosures, due to bioturbation artefact triggered by the platform installation, likely cause insufficient dosages of alum and/or calcite applied and reduced their effectiveness.