Calibration and field application of an innovative passive sampler for monitoring groundwater quality

International audienc

Ecotoxicological risk assessment linked to infilling quarries with treated dredged seaport sediments

International audienceThe dredged sediments of polluted seaports now raise complex management problems since it is no longer possible to discharge them into the sea. This results in the need to manage them on land, raising other types of technical, economic and environmental problems. Regarding the technical and economic dimensions, traditional waste treatment methods have proved to be poorly adapted, due to very high costs and low absorbable volumes. In this context, filling quarries in coastal areas with treated sediments could represent an interesting alternative for these materials. Nevertheless, for the environmental dimension, it is necessary to demonstrate that this possibility is harmless to inland ecosystems. Consequently, a specific ecotoxicological risk assessment methodology has been formulated and tested on three sediments taken from seaboards of France, in view to providing an operational and usable tool for the prior validation of any operation to fill quarries with treated seaport sediments. This method incorporates the formulation of a global conceptual model of the scenario studied and the definition of protocols for each of its steps: the characterisation of exposures (based on a simulation of sediment deposit), the characterisation of effects (via the study of sediments ecotoxicity), and the final ecotoxicological risk assessment performed as a calculation of a risk quotient. It includes the implementation in parallel of two types of complementary approach: the "substances" approach derived from the European methodology for assessing new substances placed on the market, and the "matrix" approach which is similar to methods developed in France to assess ecological risks in other domains (waste management, polluted site management, ...). The application of this dual approach to the three sediments tested led to conclude with reliability that the project to deposit sediments "1" and "2" presented a low risk for the peripheral aquatic ecosystems while sediment "3" presented a high risk

L'infiltration des eaux pluviales en milieu urbain : conséquences sur l'écosystème aquatique souterrain

International audienceL'urbanisation induit une imperméabilisation des sols et une augmentation du ruissellement, réduisant ainsi la recharge de la nappe souterraine. La gestion des eaux de pluie consiste à les collecter et les infiltrer vers la nappe qui est protégée de la pollution par des processus auto-épurateurs localisés dans le sol et la zone insaturée. Les dynamiques de la matière organique et des micro-organismes ont été suivies dans les eaux de surface et les eaux souterraines en amont et en aval des trois systèmes d'infiltration (SI). Les teneurs en Carbone Organique dissous (COD) biodégradable et réfractaire ont été mesurées sur l'eau et la croissance des biofilms a été suivie à l'aide des substrats artificiels incubés dans le milieu. Le COD diminue fortement au cours de l'infiltration, mais sa fraction biodégradable demeure plus forte en aval de SI, tout comme les biofilms qui sont stimulés par les infiltrations en biomasse et en diversité. ABSTRACT Urbanization increases impervious surfaces and stormwater runoff reducing groundwater recharge. Stormwater management mainly consists in the collection of rain water and its infiltration to the aquifer, which is protected by the self-purification capacity of the soil and the unsaturated zone. The dynamics of organic matter and microorganisms were studied in surface water and in groundwater upstream and downstream of three stormwater infiltration systems (SIS). Dissolved Organic Carbon (DOC) concentrations were measured in surface and in ground waters, while biofilm dynamics were studied using artificial substrates incubated in the waters. DOC sharply decrease from surface water to the groundwater, but the biodegradable fraction of DOC was higher downstream than upstream of the SIS and the biofilms were stimulated by the infiltration for both biomass and bacterial diversity

Maternal fish and shellfish intake and pregnancy outcomes: A prospective cohort study in Brittany, France

<p>Abstract</p> <p>Background</p> <p>Recommendations about risks and benefits of seafood intake during pregnancy have been published in the last decade, but the specific health effects of the different categories of seafood remain unknown. Fish and shellfish may differ according to their fatty acid content and their concentration of chemical pollutants and toxins. Not taking these particularities into account may result in underestimating of both the positive and negative effects of seafood on birth outcomes and partly explains inconsistent results on the subject.</p> <p>Methods</p> <p>In the PELAGIE cohort study, including 2398 pregnant women from Brittany, we fit multiple linear and logistic regression models to examine associations of fish (salt-water fish only) and shellfish intake before pregnancy with length of gestation, birthweight, and risks of preterm births, low birthweight or small-for-gestational-age (SGA) babies.</p> <p>Results</p> <p>When fish and shellfish consumptions were considered simultaneously, we observed a decrease in the risk of SGA birth with increasing frequency of fish intake: OR = 0.57 (95%CI: 0.31 to 1.05) for women eating fish twice a week or more compared with those eating it less than once a month. The risk of SGA birth was significantly higher among women eating shellfish twice a week or more than among those eating it less than once a month: OR = 2.14 (95%CI: 1.13 to 4.07). Each additional monthly meal including fish was significantly related to an increase in gestational length of 0.02 week (95%CI: 0.002 to 0.035). No association was observed with birthweight or preterm birth.</p> <p>Conclusion</p> <p>These results suggest that different categories of seafood may be differently associated with birth outcomes, fish consumption with increased length of gestation and shellfish consumption with decreased fetal growth.</p

Réponse d\u27une communauté périphytique à un effluent complexe : études en bio-essais et en canaux artificiels

Des bio-essais et des essais en canaux artificiels ont été développés pour évaluer les effets d\u27un effluent industriel riche en chlorures sur les communautés périphytiques lotiques. Les effets biologiques sont suivis à l\u27échelle de la communauté périphytique globale (biomasse), de la communauté algale (biomasse, activité photosynthètique) et de la communauté bactérienne (composition, activités enzymatiques). Cette étude montre l\u27intérêt du périphyton comme marqueur biologique et met en évidence l\u27influence du facteur saisonnier sur la sensibilité de cette communauté. Les résultats montrent que les variables aux activités enzymatiques et à la composition de la communauté bactérienne sont plus favorables à la distinction des différents traitements (variation de la concentration en effluent) que les variables de structure globale. Enfin, il apparaît que l\u27utilisation de la DGGE (Denaturating Gradient Gel Electrophoresis) pour déterminer la composition bactérienne est une technique tout à fait intéressante dans le cadre de l\u27évaluation des risques

Réponses d'une communauté périphytique à un effluent complexe (étude en bio-essais et en canaux artificiels)

Des bio-essais et des essais en canaux artificiels ont été développés pour évaluer les effets d un effluent industriel riche en chlorures sur les communautés périphytiques lotiques. Les effets biologiques sont suivis à l échelle de la communauté périphytique globale (biomasse), de la communauté algale (biomasse, activité photosynthètique) et de la communauté bactérienne (composition, activités enzymatiques). Cette étude montre l intérêt du périphyton comme marqueur biologique et met en évidence l influence du facteur saisonnier sur la sensibilité de cette communauté. Les résultats montrent que les variables aux activités enzymatiques et à la composition de la communauté bactérienne sont plus favorables à la distinction des différents traitements (variation de la concentration en effluent) que les variables de structure globale. Enfin, il apparaît que l utilisation de la DGGE (Denaturating Gradient Gel Electrophoresis) pour déterminer la composition bactérienne est une technique tout à fait intéressante dans le cadre de l évaluation des risques.Biological changes of periphytic assemblages exposed to an industrial effluent were investigated in bio-essays and artificial channels. The studied biological changes refer to the whole community (biomass), the algal community (biomass, photosynthesis) and the bacterial community (composition, enzymatic activities)? The study clearly shows the relevance of the periphytic assemblages as biological markers of a chloride-rich pollution. It also demonstrates differences in the periphytic responses depending on the seasonal factor. Moreover we observed that the more abrupt changes were related to the enzymatic activities and the bacterial composition. These biological parameters appear to be more appropriate than the other ones to the detection of various level of pollution (effluent concentrations). This work also highlights that DGGE (Denaturating Gradient Gel Electrophoresis) technique is a very powerful tool to examine the progressive changes in bacterial communities composition from peripheric assemblages under various environmental stresses.VILLEURBANNE-DOC'INSA LYON (692662301) / SudocSudocFranceF

Molecular approaches to the assessment of biodiversity in aquatic microbial communities

International audienc

Unicellular algae used as biosensors for chemical detection in Mediterranean lagoon and coastal waters

International audienceLagoons and coastal waters are contaminated by a large number of chemicals discharged directly or carried by rivers and runoff water that drain catchment areas in which agricultural activities take place. The inflow of these exogenous compounds constitutes a genuine risk for the health of ecosystems. It is therefore important to detect their presence in the natural environment before they cause irreversible damage. Here we present a study aimed at developing a tool for rapid detection of pesticides and other chemicals in environments liable to be contaminated, in order to propose an early warning system for decision-makers. The study carried out focuses on two herbicides commonly encountered in the environment, i.e. diuron and glyphosate, as well as several of their photodegradation products (DCPU, DCPMU, AMPA). The results presented contribute toward developing a biosensor based on measuring the metabolic activities of immobilized unicellular marine algae. The sensor's operation is based on measuring the esterase localized on the external membrane of the algae cells and chlorophyll fluorescence. The tests carried out show that the signal emitted by the sensor is disturbed by the presence of the two herbicides studied. The system proposed appears useful as a tool for controlling environments requiring monitoring. (C) 2011 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved

Réponse des communautés périphytiques à un rejet de déversoir d’orage simulé en canaux artificiels : influence de la durée d’exposition

L’urbanisation est source de nombreuses perturbations des milieux naturels. Lorsqu’il pleut, une partie des éléments polluants accumulés par temps sec est entraînée, puis transite dans les réseaux d’assainissement. Les surplus d’eaux pluviales sont évacués au niveau de déversoirs d’orage vers les cours d’eau récepteurs. Ces « Rejets Urbains par Temps de Pluie » se caractérisent par une grande variabilité en termes de composition, concentration, durée, fréquence. Ainsi, pour évaluer leurs effets, il est souvent nécessaire de simplifier et/ou de contrôler les systèmes d’étude. Dans des canaux artificiels en laboratoire, des communautés périphytiques naturelles ont été exposées à une eau pluviale urbaine. L’objectif était de montrer l’influence de la durée d’exposition, ainsi deux temps de contact ont été considérés (4 h et 8 h). Des descripteurs structurels (biomasses totale et algale, dénombrements bactériens), fonctionnels (activités enzymatiques leucine aminopeptidase et β-D-glucosidase) ont été suivis. Les réponses immédiates et différées (4 jours) de cette perturbation ont alors été étudiées. Le rejet augmente l’abondance et l’activité de la communauté bactérienne, mais n’a pas d’influence sur le peuplement algal. Le fait de doubler la durée d’exposition semble insuffisant pour avoir une action notable sur la réponse des biofilms

Emerging polar pollutants in groundwater: Potential impact of urban stormwater infiltration practices

International audienceThe quality of groundwater (GW) resources is decreasing partly due to chemical contaminations from a wide range of activities, such as industrial and agricultural enterprises and changes in land-use. In urban areas, one potential major pathway of GW contamination is associated with urban water management practices based on stormwater runoff infiltration systems (SIS). Data on the performance of the upper layer of soil and the unsaturated zone of infiltration basins to limit the contamination of GW by hy- drophilic compounds are lacking. With this aim, the impact of infiltration practices on GW contamination was assessed for 12 pesticides and 4 pharmaceuticals selected according to their ecotoxicological rele- vance and their likelihood of being present in urban stormwater and GW. For this purpose, 3 campaigns were conducted at 4 SIS during storm events. For each campaign, passive samplers based on the use of EmporeTM disk were deployed in GW wells upstream and downstream of SIS, as well as in the storm- water runoff entering the infiltration basins. Upstream and downstream GW contaminations were compared to evaluate the potential effect of SIS on GW contamination and possible relationships with stormwater runoff composition were examined. Our results showed two interesting opposite trends: (i) carbendazim, diuron, fluopyram, imidacloprid and lamotrigine had concentrations significantly increasing in GW impacted by infiltration, indicating a contribution of SIS to GW contamination, (ii) atrazine, simazine and 2 transformation products exhibited concentrations significantly decreasing with infiltration due to a probable dilution of historic GW contaminants with infiltrated stormwater runoff. The other 7 contaminants showed no general trend. This study demonstrates that passive samplers deployed in GW wells enabled the capture of emerging polar pollutants present at very low concen- trations and allowed the assessment of infiltration practices on GW quality. New data on GW and urban stormwater are provided for poorly studied hazardous compounds