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

International audienc

Development and use of passive sampling for mass spectrometric analysis of emerging organic pollutants in aquatic subsurface systems

Au cours de la dernière décennie, un grand nombre de contaminants tels que des pesticides et pharmaceutiques ont été détectés dans les eaux souterraines. Par conséquent, la surveillance de la qualité des eaux souterraines est devenue une nécessité dans de nombreuses régions du monde. Cependant, l'analyse des contaminants organiques dans les eaux souterraines est un défi car ils sont généralement présents à des concentrations faibles (ng L-1 à pg L-1) et variables. Les échantillonneurs passifs, tels que ceux basés sur les disques Empore™ (ED), sont des outils prometteurs puisqu’ils intègrent les évènements de pollution qui peuvent avoir lieu entre deux périodes d’échantillonnage et que l'accumulation des micropolluants sur l’échantillonneur engendre une diminution des limites de détection. Cependant, leur déploiement dans les eaux souterraines est difficile car le diamètre interne des puits de forage est généralement inférieur à celui des dispositifs. L'objectif principal de cette thèse est de développer un nouveau type d'échantillonneur par ED spécialement conçu pour un déploiement dans les eaux souterraines, et d'étudier l'applicabilité de l'échantillonnage passif à des fins qualitatives et (semi-)quantitatives pour des pesticides et pharmaceutiques polaires et semi-polaires. Ainsi, un nouvel échantillonneur par ED au design simple, peu coûteux et robuste a été conçu. Des expériences en laboratoire (étapes de conditionnement et d'élution des disques d'extraction, développement et optimisation de la méthode globale d'analyse, étude cinétique d'adsorption) et sur le terrain (déploiement dans les eaux souterraines au cours de trois campagnes) ont été entreprises et les résultats ont montré que notre échantillonneur est un outil prometteur pour des études qualitatives et (semi-)quantitatives. Notre dispositif peut être facilement inséré dans des puits de forage de taille standard et il permet une évaluation précise de la contamination des eaux souterraines en rendant possible la détection de contaminants habituellement trouvés à de très faibles concentrations. Il a également permis d'obtenir de nouvelles données (semi-)quantitatives sur des contaminants récents et peu étudiés. L'intérêt de notre échantillonneur par ED a été mis en avant dans une deuxième partie de ce travail de recherche portant sur l'impact des pratiques d'infiltration des eaux de ruissellement sur la contamination des eaux souterraines par les pesticides et pharmaceutiques polaires et semi-polaires en zone urbaineOver the last decade, a wide range of contaminants such as pesticides and pharmaceuticals have been detected in various groundwater sources. Therefore, monitoring the quality of groundwater has become a necessity in many parts of the world. Nevertheless, the measurement of organic contaminants in groundwater is challenging as they occur at low (ng L-1 to pg L-1) and variable concentrations. Passive samplers such as Empore™ disk (ED)-based passive samplers are a promising tool as they can yield time-weighted average concentrations over their deployment period and the degree of analyte pre-concentration allows for an increase overall analytical sensitivity of the procedure. However, a deployment in groundwater is not easy as the internal diameter of the well bore-holes is often smaller than passive sampler devices. The main aim of this thesis is to developed a novel type of ED-based sampler specially designed to be used in standard sized groundwater wells, and to study the applicability of passive sampling for both qualitative and (semi-)quantitative purposes for polar and semi-polar pesticides and pharmaceuticals. As a result, a simple, low cost and robust novel ED-based sampler was designed. Laboratory (conditionment and elution steps of extraction disks, overall analytical method development and optimization, uptake kinetic study) and field (deployment in groundwater during three field campaigns) experiments were undertaken and the results showed that the device is an efficient tool for both qualitative and (semi-)quantitative purposes. Our device can be easily inserted into standard sized groundwater wells, allows an accurate assessment of groundwater contamination by enabling the detection of contaminants usually found at very low concentrations, and provides new (semi-)quantitative data on recent and understudied contaminants. The usefulness of our ED-based sampler has been higlighted in a second part of this research work focusing on the impact of stormwater runoff infiltration practices on groundwater contamination by polar and semi-polar pesticides and pharmaceuticals in urban are

A Fast and Robust UHPLC-MRM-MS Method to Characterize and Quantify Grape Skin Tannins after Chemical Depolymerization

A rapid, sensitive, and selective analysis method using ultra high performance liquid chromatography coupled with triple-quadrupole mass spectrometry (UHPLC-QqQ-MS) has been developed for the characterization and quantification of grape skin flavan-3-ols after acid-catalysed depolymerization in the presence of phloroglucinol (phloroglucinolysis). The compound detection being based on specific MS transitions in Multiple Reaction Monitoring (MRM) mode, this fast gradient robust method allows analysis of constitutive units of grape skin proanthocyanidins, including some present in trace amounts, in a single injection, with a throughput of 6 samples per hour. This method was applied to a set of 214 grape skin samples from 107 different red and white grape cultivars grown under two conditions in the vineyard, irrigated or non-irrigated. The results of triplicate analyses confirmed the robustness of the method, which was thus proven to be suitable for high-throughput and large-scale metabolomics studies. Moreover, these preliminary results suggest that analysis of tannin composition is relevant to investigate the genetic bases of grape response to drought

Développement et déploiement d’échantillonnage passif pour l’analyse par spectrométrie de masse de polluants organiques émergents dans les systèmes aquatiques souterrains

Over the last decade, a wide range of contaminants such as pesticides and pharmaceuticals have been detected in various groundwater sources. Therefore, monitoring the quality of groundwater has become a necessity in many parts of the world. Nevertheless, the measurement of organic contaminants in groundwater is challenging as they occur at low (ng L-1 to pg L-1) and variable concentrations. Passive samplers such as Empore™ disk (ED)-based passive samplers are a promising tool as they can yield time-weighted average concentrations over their deployment period and the degree of analyte pre-concentration allows for an increase overall analytical sensitivity of the procedure. However, a deployment in groundwater is not easy as the internal diameter of the well bore-holes is often smaller than passive sampler devices. The main aim of this thesis is to developed a novel type of ED-based sampler specially designed to be used in standard sized groundwater wells, and to study the applicability of passive sampling for both qualitative and (semi-)quantitative purposes for polar and semi-polar pesticides and pharmaceuticals. As a result, a simple, low cost and robust novel ED-based sampler was designed. Laboratory (conditionment and elution steps of extraction disks, overall analytical method development and optimization, uptake kinetic study) and field (deployment in groundwater during three field campaigns) experiments were undertaken and the results showed that the device is an efficient tool for both qualitative and (semi-)quantitative purposes. Our device can be easily inserted into standard sized groundwater wells, allows an accurate assessment of groundwater contamination by enabling the detection of contaminants usually found at very low concentrations, and provides new (semi-)quantitative data on recent and understudied contaminants. The usefulness of our ED-based sampler has been higlighted in a second part of this research work focusing on the impact of stormwater runoff infiltration practices on groundwater contamination by polar and semi-polar pesticides and pharmaceuticals in urban areaAu cours de la dernière décennie, un grand nombre de contaminants tels que des pesticides et pharmaceutiques ont été détectés dans les eaux souterraines. Par conséquent, la surveillance de la qualité des eaux souterraines est devenue une nécessité dans de nombreuses régions du monde. Cependant, l'analyse des contaminants organiques dans les eaux souterraines est un défi car ils sont généralement présents à des concentrations faibles (ng L-1 à pg L-1) et variables. Les échantillonneurs passifs, tels que ceux basés sur les disques Empore™ (ED), sont des outils prometteurs puisqu’ils intègrent les évènements de pollution qui peuvent avoir lieu entre deux périodes d’échantillonnage et que l'accumulation des micropolluants sur l’échantillonneur engendre une diminution des limites de détection. Cependant, leur déploiement dans les eaux souterraines est difficile car le diamètre interne des puits de forage est généralement inférieur à celui des dispositifs. L'objectif principal de cette thèse est de développer un nouveau type d'échantillonneur par ED spécialement conçu pour un déploiement dans les eaux souterraines, et d'étudier l'applicabilité de l'échantillonnage passif à des fins qualitatives et (semi-)quantitatives pour des pesticides et pharmaceutiques polaires et semi-polaires. Ainsi, un nouvel échantillonneur par ED au design simple, peu coûteux et robuste a été conçu. Des expériences en laboratoire (étapes de conditionnement et d'élution des disques d'extraction, développement et optimisation de la méthode globale d'analyse, étude cinétique d'adsorption) et sur le terrain (déploiement dans les eaux souterraines au cours de trois campagnes) ont été entreprises et les résultats ont montré que notre échantillonneur est un outil prometteur pour des études qualitatives et (semi-)quantitatives. Notre dispositif peut être facilement inséré dans des puits de forage de taille standard et il permet une évaluation précise de la contamination des eaux souterraines en rendant possible la détection de contaminants habituellement trouvés à de très faibles concentrations. Il a également permis d'obtenir de nouvelles données (semi-)quantitatives sur des contaminants récents et peu étudiés. L'intérêt de notre échantillonneur par ED a été mis en avant dans une deuxième partie de ce travail de recherche portant sur l'impact des pratiques d'infiltration des eaux de ruissellement sur la contamination des eaux souterraines par les pesticides et pharmaceutiques polaires et semi-polaires en zone urbain

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

Suspect screening of emerging pollutants in groundwater and runoff water using passive sampling coupled with high resolution mass spectrometry

International audienc

Les polyphénols du raisin : Analyse MRM rapide pour explorer la réponse métabolique de résistance à la sècheresse

Les polyphénols du raisin : Analyse MRM rapide pour explorer la réponse métabolique de résistance à la sècheresse. Congrès français de Spectrométrie de Masse et d'Analyse Protéomique (SMAP 2015

Les tanins du raisin : MRM rapide pour explorer la réponse métabolique de résistance à la sécheresse

Les tanins du raisin : MRM rapide pour explorer la réponse métabolique de résistance à la sécheresse. Congrès français de Spectrométrie de Masse et d'Analyse Protéomique (SMAP 2015

Aquifer recharge by stormwater infiltration basins: Hydrological and vadose zone characteristics control the impacts of basins on groundwater chemistry and microbiology

International audienceStormwater infiltration systems (SIS) are designed to collect and infiltrate urban stormwater runoff into the ground for flood risk mitigation and artificial aquifer recharge. Many studies have demonstrated that infiltration practices can impact groundwater chemistry and microbiology. However, quantitative assessments of the hydrogeological factors responsible of these changes remain scarce. Thus, the present study aimed to quantitatively test whether changes of groundwater chemistry and microbiology induced by SIS were linked to two factors associated with vadose zone properties (vadose zone thickness, water transit time from surface to groundwater) and one factor associated with groundwater recharge rate (assessed by groundwater table elevation during rain events). To evaluate changes in chemistry (NO3−, PO43− and dissolved organic carbon concentrations), groundwater samples were collected in wells located in SIS-impacted and non-SIS-impacted zones during experimental periods of 10 days. During the same periods, clay beads were incubated in the same wells to measure changes of groundwater microbial biofilms (microbial biomass, dehydrogenase and hydrolytic activities) induced by SIS. Results showed that changes in PO43− supplied to groundwater during stormwater infiltration was negatively correlated with vadose zone thickness. A short water transit time from surface to groundwater increased dissolved organic carbon concentrations in the aquifer which, in turn, increased biofilm biomasses in groundwater. The groundwater recharge rate during rain events (assessed by groundwater table elevation) diluted NO3− concentrations in the aquifer but also influenced the changes of biofilm activities induced by SIS. Groundwater recharge rate during rain events probably increased the fluxes of water and dissolved organic carbon in groundwater, stimulating the activity of microbial biofilms. Overall, the present study is the first to quantify conjointly several factors and processes (water transfer, dilution, solute fluxes) that could explain the impact of stormwater infiltration on chemistry and/or microbiology in groundwater

Two shikimate dehydrogenases,VvSDH3andVvSDH4, are involved in gallic acid biosynthesis in grapevine

In plants, the shikimate pathway provides aromatic amino acids that are used to generate numerous secondary metabolites, including phenolic compounds. In this pathway, shikimate dehydrogenases (SDH) ‘classically’ catalyse the reversible dehydrogenation of 3-dehydroshikimate to shikimate. The capacity of SDH to produce gallic acid from shikimate pathway metabolites has not been studied in depth. In grapevine berries, gallic acid mainly accumulates as galloylated flavan-3-ols. The four grapevine SDH proteins have been produced in Escherichia coli. In vitro, VvSDH1 exhibited the highest ‘classical’ SDH activity. Two genes, VvSDH3 and VvSDH4, mainly expressed in immature berry tissues in which galloylated flavan-3-ols are accumulated, encoded enzymes with lower ‘classical’ activity but were able to produce gallic acid in vitro. The over-expression of VvSDH3 in hairy-roots increased the content of aromatic amino acids and hydroxycinnamates, but had little or no effect on molecules more distant from the shikimate pathway (stilbenoids and flavan-3-ols). In parallel, the contents of gallic acid, β-glucogallin, and galloylated flavan-3-ols were increased, attesting to the influence of this gene on gallic acid metabolism. Phylogenetic analysis from dicotyledon SDHs opens the way for the examination of genes from other plants which accumulate gallic acid-based metabolites