Search

International audience; Global warming - through the increase in frequency and intensity of meteorological extremes (heat waves, floods, etc.) - has a considerable short and long term influence on our living environment and our health. This process of global change exacerbates existing health risks and modifies the environment more generally, thus promoting air and water pollution, food insecurity, the occurrence of vector-borne diseases and the deterioration of mental health (Reports of the Lancet Countdown 2019 and 2020). The health care system itself, through its health care production activities, contributes to the global warming. The article describes the need to train health professionals on health and environment issues in order to enable them to actively participate in the ecological transition of health.; Le réchauffement climatique – de par l’augmentation en fréquence et en intensité des extrêmes (vagues de chaleur, inondations…) météorologiques – a une influence considérable à court et à long terme sur notre environnement de vie et notre santé. Ce processus de changement global aggrave les risques sanitaires existants et modifie plus généralement l’environnement, favorisant ainsi la pollution de l’air et des eaux, l’insécurité alimentaire, la survenue de maladies vectorielles et la dégradation de la santé mentale (Rapports du Lancet Countdown 2019 et 2020). Les populations les plus vulnérables sont à ce jour les plus exposées à ces risques sanitaires, mais c’est déjà l’ensemble de la planète qui ressent aujourd’hui les effets de ces phénomènes.

L’acide aminométhylphosphonique (AMPA) est le sous-produit de dégradation très répandu du glyphosate et des aminopolyphosphonates (phosphonates). L’utilisation massive de ces molécules conduit à l’omniprésence de l’AMPA dans l’environnement, et en particulier dans les eaux. L’objectif de cette revue de littérature est de résumer et de discuter les connaissances actuelles sur la formation, le transport, la persistance et la toxicité de l’AMPA dans l’environnement. Dans les sols agricoles, l’AMPA est concentré dans la couche arable et se dégrade lentement dans la plupart des sols. Il peut atteindre les eaux souterraines peu profondes, mais il est rarement retrouvé dans les eaux souterraines profondes. L’AMPA fortement adsorbé sur les particules des sols se retrouve dans les cours d’eau et les eaux de surface par ruissellement lors des événements pluvieux. Dans les zones urbaines, l’AMPA provient des aminophosphonates et du glyphosate présents dans les eaux usées et/ou les eaux pluviales selon la configuration du réseau (unitaire ou séparatif). Il est fréquemment quantifié dans le milieu récepteur en aval des stations d’épuration. Il peut être biologiquement dégradé dans les sols et les sédiments dans lesquels il a tendance à s’accumuler tandis que sa photodégradation est très limitée dans les eaux. L’AMPA aussi présent en suspension dans l’air et en quantité non négligeable peut être emporté par de fortes précipitations. Ainsi, l’AMPA provient prin - cipalement des lixiviats agricoles et des rejets d’eaux usées urbaines. La contribution domestique de l’AMPA via le glyphosate est négligeable alors que la contribution via les phosphonates reste peu renseignée. Enfin, il y a un manque critique de données épidémiologiques – en particulier sur l’exposition via l’eau – pour comprendre les effets toxicologiques de l’AMPA sur la santé humaine. Notons cependant que les stations de traitement d’eau potable permettent un abattement significatif de l’AMPA et cela même s’il n’existe pas de limite réglementaire spécifique pour les métabolites en général.

International audience; The aim of this study is to understand the spatial and seasonal variations of persistent herbicides metabolites and to determine their origins in the Vilaine River watershed, Britany-France. Improving knowledge on herbicides metabolites sources and seasonality is important for drinking water resource management. Data were collected at 13 sampling stations during five sampling campaigns in 2016 and 2017. Relations between water quality parameters, herbicides and metabolites were analyzed using statistical methods. The influence of land use and wastewater treatment plants (WWTP) on streams water quality has been identified. Cluster Analysis revealed that two groups of sampling stations can be described as “urban” with stations downstream the urban area and as “agricultural” with stations located downstream of the watershed. Chloroacetamids metabolites have been associated together with nitrates and agricultural areas as could be expected. Thus, the drinking water treatment plant located in the estuary of the Vilaine River is exposed to high metolachlor ESA and nitrate loads all year long. Aminomethylphosphonic acid (AMPA) is associated to anthropogenic urban contamination and nutrient loads. AMPA has its major sources in both glyphosate and phosphonate detergents issued from WWTP. This can help to adapt surface water treatment process and water management policies concerning herbicides metabolites.

National audience; La maîtrise de la qualité de l’air est un enjeu primordial dans les environnements sensibles comme le milieu hospitalier. La surveillance et le contrôle de la qualité biologique de l’air des hôpitaux sont essentiels et intégrés dans la démarche de prévention des maladies no-socomiales. L’objectif du projet Qaihosp est de disposer de données qualitatives et quan-titatives sur la contamination de l’air intérieur hospitalier par des substances chimiques et des agents microbiens. L’étude s’est déroulée dans deux établissements de santé français (Rennes et Nancy). Lors de ces campagnes, une pollution plutôt faible de l’air intérieur a été observée dans les deux hôpitaux. Ceci est principalement dû à une ventilation consé-quente des bâtiments qui induit un renouvel-lement d’air important. Une variabilité spatiale des concentrations a été observée principa-lement en lien avec les activités de soins et usages. Cette étude a permis aussi de faire des recommandations spécifiques en lien avec la qualité de l’air intérieur au sein des établisse-ments de santé.

National audience; Dans les structures médico-sociales et libérales, l’utilisation fréquente de produits de nettoyage et de désinfection induit une forte exposition du personnel soignant aux tensioactifs, susbtances susceptibles d’induire des dermites irritatives et/ou allergiques. L’objectif principal du projet de recherche MEDIQAI est de disposer de données qualitatives et quantitatives concernant la contamination de l’air intérieur par des substances chimiques et des agents microbiens dans différentes structures médico-sociales comme les établissements d’hébergement pour personnes âgées dépendantes, les foyers d’accueil médicalisés /maisons d’accueil spécialisées ou les maisons de retraite, et différentes structures libérales comme les cabinets de médecine en ville, les cliniques dentaires ou les pharmacies, en vue de l’évaluation de l’exposition des personnels, des résidents ou du public.

International audience; In addition to being influenced by the environment, the indoor air pollution in hospitals may be associated with specific compounds emitted from various products used, health care activities and building materials. This study has enabled assessment of the chemical and microbiological concentrations of indoor air in two French hospitals. Based on an integrated approach, the methodology defined aims to measure concentrations of a wide range of chemical compounds (>50 volatile and semi-volatile organic compounds), particle concentrations (PM and PM), microorganisms (fungi, bacteria and viruses) and ambient parameters (temperature, relative humidity, pressure and carbon dioxide). Chemical and microbiological air concentrations were measured during two campaigns (winter and summer) and across seven rooms (for spatial variability). The results have shown that indoor air contains a complex mixture of chemical, physical and microbiological compounds. Concentrations in the same order of magnitude were found in both hospitals. Compared to dwelling indoor air, our study shows low, at least equivalent, contamination for non-hospital specific parameters (aldehydes, limonene, phthalates, aromatic hydrocarbons), which is related to ventilation efficiency. Chemical compounds retrieved at the highest concentration and frequencies are due to healthcare activities, for example alcohol - most commonly ethanol - and hand rubbing (median concentration: ethanol 245.7 μg/m and isopropanol 13.6 μg/m); toluene and staining in parasitology (highest median concentration in Nancy laboratory: 2.1 μg/m)).

International audience; During the treatment process of drinking water, disinfectants (chlorine, ozone, chlorine dioxide) react on water containing organic matter and bromide to produce disinfection by-products at trace levels. Among them, five of the nine existing halo-acetic acids (HAAs) are commonly found in drinking water (monochloroacetic acid (MCAA), dichloroacetic acid (DCAA), monobromoacetic acid (MBAA), dibromoacetic acid (DBAA), and Trichloroacetic acid (TCAA)), including four classified in the 2B IARC group of potential carcinogens (BCAA, DBAA, DCAA, TCAA). With respect to drinking water quality, guidelines are proposed by WHO (2006) and water quality standards are imposed in many countries such as less than 100 μg/L for the sum of the five HAAs by US EPA (1998) and Canadian Health Department (2008). For this purpose, two analytical methods are commonly used, GC/MS with derivatization and LC/MS, UV or conductivity. A new method, based on two-dimensional ion chromatography (IC 2D) with suppressed conductivity is proposed. This method presents the main advantage of offering a quick implementation compared to GC or LC methods: direct injection, slight maintenance, lower cost of investment, by leading to good performances (specificity and sensitivity). The use of two different selectivity columns, and the fractionation on the first dimension canceling interferences, improves the specificity. The sensitivity is enabled by interfacing a preconcentration column between the two different internal diameter columns. The analytical conditions are optimized for the analysis of nine HAAs. The performances of the method are evaluated. The optimized method applied to natural water samples demonstrates its ability to quantify HAAs at trace levels in drinking water.

International audience; The adsorption of some major pharmaceutical products (sulfamethoxazole, caffeine, iopromide and carbamazepine) in water was evaluated using four types of activated carbon, three powdered activated carbon (PAC) and one fluidized, coagulated and flocculated activated carbon (FAC) extracted from a Carboplus®P pilot. These substances were the most frequently quantified (in 50% of samples at least) in surface waters of the Vilaine's basin (Brittany, France) during three sampling campaigns. Jar test experiments were carried out in order to assess the removal efficiency of the four activated carbons. Carbamazepine and caffeine were well removed with PAC with a maximum removal rate of 80% whereas it was more difficult for sulfamethoxazole and iopromide with a maximum of 39%. For each molecule, removal rates are clearly dependent on PAC nature. The overall results with FAC are clearly distinguishable from PAC tests with gains of performance on all target molecules (from 80 to >95%).

International audience; The widely occurring degradation product aminomethylphosphonic acid (AMPA) is a result of glyphosate and amino-polyphosphonate degradation. Massive use of the parent compounds leads to the ubiquity of AMPA in the environment, and particularly in water. The purpose of this review is to summarize and discuss current insights into AMPA formation, transport, persistence and toxicity. In agricultural soils, AMPA is concentrated in the topsoil, and degrades slowly in most soils. It can reach shallow groundwater, but rarely managed to enter deep groundwater. AMPA is strongly adsorbed to soil particles and moves with the particles towards the stream in rainfall runoff. In urban areas, AMPA comes from phosphonates and glyphosate in wastewater. It is commonly found at the outlets of Wastewater Treatment Plants (WWTP). Sediments tend to accumulate AMPA, where it may be biodegraded. Airborne AMPA is not negligible, but does wash-out with heavy rainfall. AMPA is reported to be persistent and can be biologically degraded in soils and sediments. Limited photodegradation in waters exists. AMPA mainly has its sources in agricultural leachates, and urban wastewater effluents. The domestic contribution to urban loads is negligible. There is a critical lack of epidemiological data - especially on water exposure - to understand the toxicological effects, if any, of AMPA on humans. Fortunately, well operated water treatment plants remove a significant proportion of the AMPA from water, even though there are not sufficient regulatory limits for metabolites.

Introduction L’objectif de cette etude est de disposer de donnees qualitatives et quantitatives sur la contamination de l’environnement interieur hospitalier, microbiologique et chimique, afin d’evaluer l’exposition du personnel, des visiteurs et des patients et la variabilite spatio-temporelle de la contamination. Methodes L’etude s’est deroulee dans differents lieux des CHU de Rennes et de Nancy : hall d’accueil, salle de soins infirmiers, salle de reveil post-operatoire, chambre d’un patient, unite de desinfection des endoscopes, laboratoire de parasitologie et salle de decoupe de plâtres. Deux campagnes de prelevement ont eu lieu en ete 2014 et en hiver 2015. Les methodes de prelevement etaient nombreuses et complementaires ( Fig. 1 ). L’analyse des donnees a ete realisee sous IBM SPSS grâce au test de Mann-Whitney et le coefficient de correlation de Pearson. Resultats Les concentrations d’aldehydes, de composes organiques volatils (COV) et semi-volatils etaient faibles a tres faibles dans les 2 etablissements. Etaient detectables, mais sans differences globales entre les 2 etablissements : la contamination fongique (m = 226 UFC/m3 ; p = 0,97) ou bacterienne (m = 352 UFC/m3 ; p = 0,14), les particules PM2,5 (m = 2,1 μg/m3 ; p = 0,97) et PM10 (m = 6,6 μg/m3 ; p = 0,84). Sur le plan saisonnier, la contamination fongique etait plus importante en ete pour les 2 etablissements (p = 0,002). La contamination bacterienne ne varie pas significativement entre les locaux (p = 0,14) contrairement a la contamination fongique (p = 0,02) et particulaires PM2,5 (p = 0,01) ou PM10 (p = 0,01). Cette derniere est plus importante dans le hall (m = 879 UFC/m3), le laboratoire de parasitologie (m = 333 UFC/m3) et la salle de plâtre (m = 310 UFC/m3). Nous ne retrouvons pas de correlation significative entre le nombre de personnes, le taux de CO2, l’humidite relative et le denombrement bacterien ou fongique. Neanmoins nous retrouvons une relation forte entre la temperature du local et la contamination bacterienne (r = 0,7, p = 0,008) ou la contamination fongique (r = 0,56, p = 0,045) d’une part, et entre la contamination fongique et les PM10 (r = 0,52, p = 0,022) d’autre part. Conclusion Notre etude montre une tres faible contamination par les aldehydes, COV et sCOV comparativement a d’autres lieux publics. La forte variabilite spatio-temporelle de la contamination fongique et particulaire est liee a la saison, a l’activite et a la ventilation.

International audience; Cyanobacteria and their toxins are known as a health hazard in recreative and distributed waters. Monitoring data from 2004 to 2011 were collected at regional scale to characterize exposition parameters to microcystins in Brittany (Western France). The data show that cyanobacteria populations are experiencing a composition shift leading to a longer duration of cell densities higher than WHO alert levels 2 and 3. Microcystins however appear to be more frequently detected with subacute concentrations in low cell density samples than in high cell density samples or during bloom episodes. Positive relations are described between microcystin concentrations, detection frequencies and cyanobacteria biovolumes, allowing for a novel definition of alert levels and decision framework following WHO recommendations

International audience; Heavy rainfall events, increasing in frequency and intensity with climate change, impact on the quality of the water resource used for drinking-water production. Small-scale water suppliers are particularly sensitive because of their management and the related difficulties of adapting treatment to variations. Decision-support systems, based on monitoring and analytical tools, need to be developed to improve crisis-management procedures related to such events. After presenting the issues related to heavy rainfall events, the article summarizes the tools currently used for quality control of drinking water within this framework, the need for developments and other requirements.

International audience; The water quality monitoring program implemented by the sanitary authorities defines the sampling frequency and parameters to be measured regarding the facilities characteristics climatic events (heavy rains, floods, droughts). For example the water quality produced by small systems is monitored between once a year and every five years depending of the population supplied without consideration of weather.However, these climatic events constitute a big public health issue because chemical and microbiological contaminants may enter surface waters or aquifers leading to potentially short or medium term risks for human health.Complementary to the sanitary water quality monitoring of resources and drinking waters, the self monitoring of water carried out by the water supply system manager, could be modified in order to integrate at risk situations in the frame of the water safety plans approach proposed by WHO. The early detection of simple, rapid and relevent parameters indicators of water qualty safety with respect to the financial frame of small and medium water supply systems could improve the management of sanitary risks.For risks assessment the measurement of turbidity, correlated with the presence of pathogens, of conductivity for minerals dilution or concentration, and spectrophotometry UV giving parameters estimation and substances detection, must be considered. This monitoring approach could be very useful for adaptation to rapid changes in water quality linked to climatic events and to maximize the efficiency of treatment processes and of the general functioning of the treatment plant.; En France, les petites et moyennes unités de distribution d’eau destinée à la consommation humaine sont majoritaires en nombre bien que n’alimentant qu’environ 10 % de la population. Comme les autres unités de distribution, elles sont sujettes à un programme de contrôle de la qualité de l’eau, fait par les autorités sanitaires, qui définit les fréquences de prélèvements et les paramètres à analyser selon les caractéristiques des installations et les populations desservies. Ce programme ne tient pas compte des événements climatiques (fortes pluies, inondations, sécheresses), qui pourtant constituent un enjeu de santé publique important puisqu’ils favorisent l’introduction de contaminants chimiques et microbiologiques dans les eaux de surface et les nappes phréatiques, induisant des risques à court et à long terme pour la santé des populations. En complément du contrôle sanitaire, l’autocontrôle proposé pour les exploitants, pourrait intégrer les situations à risques, conformément à la démarche d’évaluation et de gestion des risques tout au long du cycle de production d’eau jusqu’au robinet du consommateur prévue dans la mise en œuvre des Water Safety Plans. La détection précoce de paramètres susceptibles d’altérer la qualité de l’eau par des techniques simples et rapides qui prennent en compte les contraintes financières et techniques de ces unités de distribution, permettrait d’améliorer la maîtrise des risques sanitaires. L’estimation du risque microbiologique et chimique par des méthodes telles que la mesure de turbidité, la spectrophotométrie, la mesure de conductivité permettre de s’adapter aux changements rapides de la qualité de l’eau induits par les événements climatiques et de maximiser ainsi l’efficacité des procédés de traitement et les activités d’exploitation de la station de traitement

Besides climate change impacts on water availability and hydrological risks, the consequences on water quality is just beginning to be studied. This review aims at proposing a synthesis of the most recent existing interdisciplinary literature on the topic. After a short presentation about the role of the main factors (warming and consequences of extreme events) explaining climate change effects on water quality, the focus will be on two main points. First, the impacts on water quality of resources (rivers and lakes) modifying parameters values (physico-chemical parameters, micropollutants and biological parameters) are considered. Then, the expected impacts on drinking water production and quality of supplied water are discussed. The main conclusion which can be drawn is that a degradation trend of drinking water quality in the context of climate change leads to an increase of at risk situations related to potential health impact. Keywords: Climate change, Water quality, Warming, Extreme events, Floods, Droughts, Organic carbon, Nutrients, Micropollutants, Cyanotoxins

The composition of water and wastewater, varying temporally and spatially, depends on factors such as environmental context, types of pollution sources, weather conditions leading to dilution or solids transportation, length of sewer network, etc. Because quantitative parameters are often not adapted for the characterization of wastewater quality variability, a non-parametric measurement is proposed, based on comparison of the UV absorption spectra of samples. The presence of isosbestic points, occurring in the set of spectra either directly or indirectly after normalization, allows quantification of the variability of a given water or effluent. A normalization step is used when dilution exists in the case of a mixture of water types (discharge or rain). Several examples show how to calculate the variability or to estimate the dilution factor from UV spectra data, even without results of physicochemical parameters.

International audience; In spite of several studies on factors affecting nitrogen (N) export in water, the spatiotemporal variability of N export is rarely addressed. This review aims at discussing the different factors involved in N export in water and the intra-annual variability of N occurrences in rivers at a watershed scale. From the analysis of the existing works some recommendations on future research work are proposed regarding (i) other N forms than nitrate being systematically considered for routine analysis or experimental studies (at least Kjheldal nitrogen), (ii) hydrologists and biogeochemists working together to better understanding of N dynamics according to water pathways, especially during “situations at risk,” (iii) water quality monitoring being reinforced both spatially and temporally, especially thanks to high frequency instrumentation, and (iv) accurate data on watersheds needed to give better explanations of N variations. We argue that a better understanding of spatiotemporal variability could greatly enhance the remediation of N export impacts, which is crucial to anticipate the impacts of global changes.

International audience; There is emerging concern over the impact of extreme events such as heavy rainfall on the quality of water entering the drinking water supply from aboveground sources, as such events are expected to increase in magnitude and frequency in response to climate change. We compared the impact of rainfall events on streamwater quality in four contrasting upland (peatland and mineral soil) and lowland agricultural catchments used to supply drinking water in France (Brittany) and the United Kingdom (North Wales) by analyzing water samples collected before, during, and after specific events. At all four streams, heavy rainfall led to a considerable rise in organic matter concentration ranging from 48 to 158%. Dissolved organic carbon (DOC) quality, as determined using specific ultraviolet absorbance, changed consistently at all sites during rainfall events, with a greater proportion of aromatic and higher molecular weight compounds following the onset of rainfall. However, the change in DOC quality and quantity did not significantly alter the trihalomethane formation potential. We observed small increases in trihalomethane (THM) generation only at the Welsh peatland and agricultural sites and a small decrease at the Brittany agricultural site. The proportion of brominated THMs in chlorinated waters was positively correlated with bromide/DOC ratio in raw waters for all sites and hydrological conditions. These results provide a first indication of the potential implications for surface-based drinking water resources resulting from expected future increases in rainfall event intensity and extension of dry periods with climate changes.

International audience; Microbial pollution in aquatic environments is one of the crucial issues with regard to the sanitary state of water bodies used for drinking water supply, recreational activities and harvesting seafood due to a potential contamination by pathogenic bacteria, protozoa or viruses. To address this risk, microbial contamination monitoring is usually assessed by turbidity measurements performed at drinking water plants. Some recent studies have shown significant correlations of microbial contamination with the risk of endemic gastroenteresis. However the relevance of turbidimetry may be limited since the presence of colloids in water creates interferences with the nephelometric response. Thus there is a need for a more relevant, simple and fast indicator for microbial contamination detection in water, especially in the perspective of climate change with the increase of heavy rainfall events. This review focuses on the one hand on sources, fate and behavior of microorganisms in water and factors influencing pathogens' presence, transportation and mobilization, and on the second hand, on the existing optical methods used for monitoring microbiological risks. Finally, this paper proposes new ways of research.

International audience; Cyanobacteria are a component of public health hazards in freshwater environments because of their potential as toxin producers. Eutrophication has long been considered the main cause of cyanobacteria outbreak and proliferation, whereas many studies emphasized the effect of abiotic parameters (mainly temperature and light) on cell growth rate or toxin production. In view of the growing concerns of global change consequences on public health parameters, this study attempts to enlighten climate influence on cyanobacteria at regional scale in Brittany (NW France). The results show that homogeneous cyanobacteria groups are associated with climatic domains related to temperature, global radiation and pluviometry, whereas microcystins (MCs) occurrences are only correlated to local cyanobacteria species composition. As the regional climatic gradient amplitude is similar to the projected climate evolution on a 30-year timespan, a comparison between the present NW and SE situations was used to extrapolate the evolution of geographical cyanobacteria distribution in Brittany. Cyanobacteria composition should shift toward species associated with more frequent Microcystins occurrences along a NW/SE axis whereas lakes situated along a SW/NE axis should transition to species (mainly Nostocales) associated with lower MCs detection frequencies.

International audience; A strong non linear relationship between nitrate and organic matter (assessed by dissolved organic carbon, DOC) has been recently demonstrated by Taylor and Townsend (2010), namely for freshwaters. In this context, our study explores this relation from the behavior of sets of normalized UV spectra (same area under each spectrum) of different water samples showing a hidden isosbestic point (HIP) around 225 nm. This HIP is linked to the existence of a simple relation between nitrate and DOC, the proportions of which vary according to the sampling location and environmental factors. In a second step, a simple linear model is proposed for nitrate-DOC relationship (α⋅NO3+β⋅DOC=1) and a validation is proposed for more than 150 samples of different Brittany rivers and lakes. For samples of the largest watershed, a complementary exploitation from data acquired during the different campaigns confirmed the seasonal evolution between spring (high nitrate/low DOC) and autumn (high DOC/low nitrate). Further investigation on other freshwater samples is needed in order to improve the limits of this linear model.

International audience; This paper proposes a new approach for the on-site detection of micropollutants in water in case of accidental or intentional contamination (characterized by high concentration). The technique is based on the use of an automatic multiple solid phase extraction step (MSPE) followed by direct or indirect UV spectrometry (MSPE/UV) for the detection of organic contaminants in water (such as regulated molecules (pesticides ...) as well as emerging pollutants (pharmaceutical products, endocrine disruptors ...)). The development of the system supposes firstly the choice of the most appropriate sorbent(s) and secondly conditions for the detection of targeted micropollutants, from several solid phase extraction cartridges and eluting solvents. Two different extraction sorbents were chosen. These sorbents and several eluting solvents allow the first separation of the compounds based on the physico-chemical properties of each substance (pKa, log Kow) and on the specific interactions with the sorbent. Finally, a UV analysis (either at the maximum of absorbance using a calibration curve or from the whole spectrum using a multicomponent (deconvolution) exploitation method) of each fraction allows a determination and a quantification of each compound. The method is rapid (less than 2 h), sensitive enough for an accidental/intentional contamination (between 5 and 40 μg*L− 1 according to the substances) and with a good precision (between 4 and 14%).

International audience; Over the last two decades, climate change has become a major environmental and public health concern due to the increase of the mean temperature on the Earth and its consequences on extreme meteorological events such as floods and droughts. These events induce very low or very high river flows that may impair surface water quality, and therefore result in potential health impacts when used for drinking water production. The present study aims at assessing the impact of hydrologic regime on surface water quality with a particular emphasis on total organic carbon (TOC) and nitrate. Water quality data from three French rivers acquired over a 27 years period, from January 1983 to December 2009, show the influence of extreme flows. Variation in TOC and nitrate concentrations showed opposite patterns for the whole range of flow rate (from less than 10% up to more than 100% of the mean flow). Regarding fluxes, TOC increased continuously with flow rate while nitrate was stable for very high discharges. The C/N ratio expressed from TOC and nitrate concentrations showed high values for extreme flows and particularly for very low flow rates, generally in summer, where nitrate is assimilated by biomass. Considering TOC and nitrate fluxes, it is confirmed that the worst situations were encountered for very high flow rates, namely for TOC exportation during surface runoff which was related to heavy rains or floods. These findings are of great importance with regard to the adaptation for drinking water treatment in facing extreme hydrological conditions, of which the frequency is increasing with climate change.

Drinking water (DW) is increasingly subject to environmental and human threats that alter the quality of the resource and potentially of the distributed water. These threats can be both biological and chemical in nature, and are often cumulated. The increase of technical frame of water quality monitoring following the evolution of water quality standards guarantee the regulation compliance in general but is not sufficient for the survey of small scale water system efficiency. The existing monitoring is not well suited to insure a good quality of distributed water, especially in the event of a sudden modification of quality. This article aims to propose alternative solutions, from the examination of monitoring practices, in a bid to limit the risk of deterioration of DW quality.

International audience; This study aims at understanding the presence of regulated and emerging micropollutants, particularly pesticides and pharmaceuticals, in surface water, regarding spatial and temporal influences at a watershed scale. The study of relations between micropollutants and other water quality and hydroclimatic parameters was carried out from a statistical analysis on historical and experimental data of different sampling sites from the main watershed of Brittany, western France. The outcomes point out the influence of urban and rural areas of the watershed as well as the impact of seasons on contamination variations. This work contributes to health risk assessment related to surface water contamination by micropollutants. This approach is particularly interesting in the case of agricultural watersheds such as the one studied, where more than 80% of surface water is used to produce drinking water.

Cyanobacteria are ubiquitous microorganisms considered as important contributors to the formation of Earth's atmosphere and nitrogen fixation. However, they are also frequently associated with toxic blooms. Indeed, the wide range of hepatotoxins, neurotoxins and dermatotoxins synthesized by these bacteria is a growing environmental and public health concern. This paper provides a state of the art on the occurrence and management of harmful cyanobacterial blooms in surface and drinking water, including economic impacts and research needs. Cyanobacterial blooms usually occur according to a combination of environmental factors e.g., nutrient concentration, water temperature, light intensity, salinity, water movement, stagnation and residence time, as well as several other variables. These environmental variables, in turn, have promoted the evolution and biosynthesis of strain-specific, gene-controlled metabolites (cyanotoxins) that are often harmful to aquatic and terrestrial life, including humans. Cyanotoxins are primarily produced intracellularly during the exponential growth phase. Release of toxins into water can occur during cell death or senescence but can also be due to evolutionary-derived or environmentally-mediated circumstances such as allelopathy or relatively sudden nutrient limitation. Consequently, when cyanobacterial blooms occur in drinking water resources, treatment has to remove both cyanobacteria (avoiding cell lysis and subsequent toxin release) and aqueous cyanotoxins previously released. Cells are usually removed with limited lysis by physical processes such as clarification or membrane filtration. However, aqueous toxins are usually removed by both physical retention, through adsorption on activated carbon or reverse osmosis, and chemical oxidation, through ozonation or chlorination. While the efficient oxidation of the more common cyanotoxins (microcystin, cylindrospermopsin, anatoxin and saxitoxin) has been extensively reported, the chemical and toxicological characterization of their by-products requires further investigation. In addition, future research should also investigate the removal of poorly considered cyanotoxins (β-methylamino-alanine, lyngbyatoxin or aplysiatoxin) as well as the economic impact of blooms. Keywords: Drinking water treatment, Microcystin, Anatoxin, Cylindrospermopsin, Saxitoxin, BMAA

International audience; This study proposes a new approach for improving resource quality management, monitoring and treatment plant management, whatever the environmental and climatic stressors. First trend analysis of water quality at a river basin scale, based on historical water quality data and multivariate exploitation (principal component analysis, PCA), led to a classification of the monitoring stations with regard to the main pressures (land use, urbanization and hydroclimatic impacts). This method was applied to the Vilaine's watershed, the largest river basin in Brittany, western France, and one which is under agricultural and urban pressure. A complementary research using a UV index was proposed for the evaluation of spatial and temporal variations of water quality. This approach may be considered as a useful and relevant tool to quickly assess the variation of water quality and the main explanatory factors. It also points out monitoring stations under specific stressors considered as outliers regarding UV parameters. Finally, PCA and UV index give complementary results. PCA allows factors influencing drinking water resource to be highlighted and the UV index allows global water quality under specific times and impacts to be reflected.

International audience; Since a rise in dissolved organic carbon (DOC) concentrations has been observed for surface waters at least over the last two decades, a change in weather conditions (temperature and precipitations) has been proposed to partly explain this increase. While the majority of DOC delivery from soils to stream occurs during rainfall events, a better understanding of the rainfall influence on DOC release is needed. This study has been conducted in Brittany, western France, on agricultural experimental plots receiving either cattle manure (CM) or pig slurry (PS) as fertilizers in accordance with local practices. Each plot was instrumented with a flow meter and an auto sampler for runoff measurements. The results show that export of DOC during high intensity events is higher than during lower intensity rainfalls. Fertilization has a noticeable impact on total organic carbon (TOC) fluxes with an increase of five to seven folds for PS and CM respectively. If TOC shock load occurs shortly after the rainfall peak, DOC maximum appears with the first flush of the event. Organic carbon (OC) is mainly under colloidal (41.2%) and soluble (23.9%) forms during the first stage of a rainfall event and a control of rainfall intensity on OC colloidal transport is suggested. These findings highlight the potential risk of receiving water quality degradation due to the increase of heavier rainfall events with climate change in temperate areas.

International audience; As climate change could impact water quantity and quality, important concerns are related to water quality degradation in small scale water services (SSWS). SSWS using surface waters resources (rivers and lakes) for drinking water production are particularly vulnerable to short term transient events due to their low adaptation capacity and their lack of support and technical knowledge compared to major centralized systems. Based on weather and water quality databases, a case study was conducted on a SSWS in Brittany (France) pumping from surface water. Results show an important vulnerability in treatment efficiency related to the lowest and highest river flows and provide first assumptions about the impacts of an increase in extreme weather events with climate change on drinking water quality.

International audience; Environmental context The safeguarding of water supplies and drinking water is a major issue when considering human health risk management. In this context, an automatic and on-site fractionation system for the detection of organic contaminants has been developed. The main goal of this system is to establish an initial diagnosis by identifying a class of substances involved in a case of pollution. Abstract This paper proposes a new approach for the preconcentration, fractionation, prediction and detection of organic micropollutants in water. The main aim of this study was to implement an innovative fractionation method and a prediction model based on the physicochemical properties of compounds and interactions with the sorbent of solid-phase extraction cartridges. Two sorbents (Strata-SAX and Oasis-HLB) and three specific eluting solvents (mixture of methanol and sodium chloride and mixtures of acetonitrile and ultrapure water) were used to separate organic compounds into five specific fractions according to their physicochemical properties (anionic and cationic or neutral compounds with various polarity). More than 75 molecules (43 molecules individually studied and a mixture with 43 molecules, including 11 molecules individually studied) including pesticides, pharmaceuticals, endocrine disruptors and polycyclic aromatic hydrocarbons, with various properties were studied, and the results showed that the elution fraction can be predicted for more than 85% of the compounds. This methodology could simplify the analytical chain by reducing detailed analysis on limited categories of compounds, and could be used for a rapid and on-site screening of organic compounds. © CSIRO 2016.

Urban wastewater treatment plant efficiency, as well as biosolid quality, depends on urban wastewater quality, which can be affected by non domestic discharges (industrial, commercial etc.). The characterization of wastewater quality and non domestic discharge is complex, expensive and time consuming. However, these discharges must be controlled and reduced if possible. The development of a simple and fast methodology, namely based on alternative methods such as UV spectrophotometry, has been carried out and applied to different areas of a medium sized town of Southern Quebec (Canada). Several autosamplers and on line/on site measurements have been used in critical control points of the network areas, for a dry weather campaign in four areas (industrial, commercial, hospital and university). The flow rate study, completed by the exploitation of conductivity measurements and the qualitative examination of UV spectra allows the discrimination of non domestic loads and their variability study from one point to another. The identification of critical discharges and organic shock loads has been possible with low investment, and mitigation actions have been proposed.

Publisher Summary This chapter examines the ultraviolet (UV) spectra of raw industrial effluents with respect to the industrial activity. Practical qualitative and quantitative applications, concerning petrochemistry, are proposed. Raw industrial effluents can be classified according to the dominant nature of pollution, organic or mineral. Raw industrial wastewater is generally produced continuously during the industrial process, but can include some other liquid wastes such as washing residues and process water, in case of an incident. One of the most important applications of UV spectrophotometry, particularly for industrial wastewater quality control, is the rapid estimation of the concentration of some substances or some parameter values, among which are aggregate organic parameters and N or P compounds. Physico-chemical treatments of urban wastewater include either separation techniques or processes based on a chemical reaction. A treatability study is often needed for designing an industrial treatment plant. As biological processes are often preferred, biodegradation tests are carried out.

A complementary approach of environmental analytical chemistry is presented in this paper. The non parametric measurement (NPM) concept is based on the direct exploitation of an analytical signal (absorbance, intensity, potential, …) without parameter calculation, leading to the simple characterisation of the studied sample. For example, the existence of a direct isosbestic point for a set of absorption spectra (point where spectra cross together) shows that the global quality of the medium is conserved and is in equilibrium between two given states (without considering non absorbing species). From the calculation of the ratio of (1) the number of spectra crossing at a given isosbestic point, on (2) the total number of spectra, the global quality variability can be simply estimated, without any knowledge of the medium composition. After the explanation of the NPM concept, the study of an industrial wastewater network in a refinery site is presented. Starting from the sampling of wastewater along a network branch, the calculation of variability is carried out with the study of isosbestic points after normalisation (in order to take the dilution effect into account). The examination of UV spectra shape brings complementary qualitative information. Moreover, the quantitative exploitation of spectra is obviously possible, namely by the use of a deconvolution method. Limiting the application to the results of NPM, the study shows that the global variability decreases from the process units to the outlet of the wastewater treatment plant (end of pipe)., L’exploitation directe de signaux analytiques peut, sans donner lieu à un résultat de mesure, conduire à l’obtention d’informations utiles concernant par exemple la caractérisation d’un milieu environnemental. Cette démarche est celle de la mesure non paramétrique qui permet rapidement et simplement de compléter les informations données par des méthodes analytiques classiques. Une application concernant l’étude du réseau d’assainissement industriel d’une raffinerie est présentée dans cet article. L’étude de la variabilité qualitative globale de l’effluent le long du réseau, réalisée par l’exploitation des faisceaux de spectre d’absorption UV, montre que celle-ci diminue de la sortie des unités vers le rejet des effluents traités.