Présence, origine et toxicité des sous-produits de désinfection dans les piscines chlorées : vue d'ensemble

International audienceDisinfection treatments are critical to conserve the microbiological quality of swimming pool water and to prevent water-borne infections. The formation of disinfection byproducts (DBPs) in swimming pools is an undesirable consequence resulting from reactions of disinfectants (e.g. chlorine) with organic and inorganic matter present in pool water, mainly brought by bathers. A considerable body of occurrence studies has identified several classes of DBPs in swimming pools with more than 100 compounds detected, mainly in chlorinated freshwater pools. Trihalomethanes (THMs), haloacetic acids (HAAs), haloacetaldehydes (HALs) are among the major DBPs in swimming pools. Other DBPs such as haloacetonitriles (HAN), haloamines, nitrosamines, and halobenzoquinones have also been detected. Researchers have been interested in identifying the precursors responsible for the formation of DBPs. In swimming pools, anthropogenic organic loads brought by swimmers increase the complexity of pool water chemistry. When human inputs (e.g. sweat, urine, hair, skin and personal care products) containing very diverse organic compounds are introduced to pools by swimmers, they react with chlorine resulting in the formation of complex mixtures of DBPs. The overwhelming majority of the total organic halide (TOX) content is still unknown in swimming pools. Exposure of swimmers to DBPs can take place through multiple routes, depending on the chemical properties of each DBP. Toxicological studies have shown that swimming pool water can be mutagenic with different potencies reported in different studies. Many DBPs have been shown to be genotoxic 2 and carcinogenic. DBPs were also shown to induce reproductive and neurotoxic adverse effects in animal studies. Epidemiologic studies in humans have shown that exposure to DBPs increases the risk of respiratory adverse effects and bladder cancer. Association between DBPs and other health effects are still inconclusive. Data gathered in the present review (occurrence, toxicity, and toxicological reference values) could be used in conducting chemical risk assessment studies in swimming pools

Transferts et mobilité des éléments traces métalliques dans la colonne sédimentaire des hydrosystèmes continentaux

Dans les cours d eau, les éléments traces métalliques (ETM) sont transférés sous formes dissoutes et/ou fixées aux particules. Sous cette dernière forme, ils peuvent s accumuler dans les zones sédimentaires et constituer des stocks de polluants. A terme, ces stocks peuvent poser un risque pour la qualité des hydrosystèmes si des changements environnementaux conduisent à accroître leur mobilité. Dans ce contexte, ces travaux ont concerné la mobilité par diffusion interstitielle. Pour cela, il est important de connaitre comment les ETM se répartissent entre leurs formes mobiles. Ce fractionnement dissous particulaire des ETM est régi par les réactions de sorption à la surface des particules. Ces réactions dépendent des conditions physico-chimiques du milieu et sont fortement influencées par les processus biogéochimiques de la diagénèse précoce. Afin d appréhender ces processus, ce travail s appuie sur une approche mixte qui associe terrain, analyse et modélisation. La partie terrain a impliqué 9 campagnes de prélèvements de carottes de sédiment (Durance et Rhône). Ces échantillons ont été analysés selon un protocole qui permet d obtenir les distributions verticales des paramètres physico-chimiques, des nutriments et des formes solide - liquide des ETM ciblés. L analyse et l interprétation de ces résultats expérimentaux s appuient sur un modèle qui a été développé au cours de cette étude et qui intègre : un modèle de diffusion interstitielle, un modèle biogéochimique, un modèle de calcul du pH et un modèle d échanges solide liquide. Les résultats mettent en évidence que la disponibilité des ETM considérés est fortement liée au comportement des phases porteuses biogéochimiques et que la mobilité par diffusion interstitielle dépend essentiellement des caractéristiques granulométriques qui conditionnent à la fois la diffusion et la distribution des phases porteuses biogéochimiques.AIX-MARSEILLE1-BU Sci.St Charles (130552104) / SudocSudocFranceF

Inorganic chloramines analysis in water

International audienceAnalysis of inorganic chloramines in waters is of particular interest in the field of drinking waters as they are at the origin of many others disinfection by-products (DBPs). They are formed when free chlorine reacts with nitrogen containing substances present in chlorinated water sources. Their presence is generaly unwanted (except for monochloramine when used a secondary disinfectant) and bears witness of the presence of other potentially more toxic DBPs. Their analysis is also challenging because of their high reactivities, unstabilities in waters, low molecular weight, and high polarity. This chapter introduces first the physical-chemical properties of inorganic chloramines presents, then their modes of preparation (as no standard of inorganic chloramines are commercially-available), and finally the different methods available for analysis of total chloramines and for discrimination of monochlormaine, dichlormaine and trichloramine, in waters

Inorganic chloramines analysis in water

International audienceAnalysis of inorganic chloramines in waters is of particular interest in the field of drinking waters as they are at the origin of many others disinfection by-products (DBPs). They are formed when free chlorine reacts with nitrogen containing substances present in chlorinated water sources. Their presence is generaly unwanted (except for monochloramine when used a secondary disinfectant) and bears witness of the presence of other potentially more toxic DBPs. Their analysis is also challenging because of their high reactivities, unstabilities in waters, low molecular weight, and high polarity. This chapter introduces first the physical-chemical properties of inorganic chloramines presents, then their modes of preparation (as no standard of inorganic chloramines are commercially-available), and finally the different methods available for analysis of total chloramines and for discrimination of monochlormaine, dichlormaine and trichloramine, in waters

Individual volatile fatty acids determination by chromogenic derivatization coupled to multi-syringe chromatography

International audienceIn this paper, a new multisyringe chromatography (MSC) system is proposed for a simple and accurate measurement of individual volatile fatty acids (VFA) in anaerobic treatment processes. The determination method is based on the derivatization of VFA with N-(1-naphthyl) ethylenediamine (EDAN) followed by the separation of VFA derivatives on an Onyx C18 monolithic column (25 mm x 4.6 mm i.d.). Chromatographic separation conditions have been investigated and were found to be optimal with a mixture of acetonitrile and formic acid 0.1% (ratio 35/65), providing good separation of C-2-C-5 VFA in 8 min. Optimization of the derivatization reaction was also carried out with special attention paid to the buffering capacity of the reaction medium, so as to be able to deal with samples of various characteristics in terms of alkalinity or of VFA concentration range. Individual VFA could be quantified between 0.05-2.5 g L-1 with LOD of 0.01-0.02 g L-1. Overall procedure time was about 18 min for one analytical cycle, which fulfils the requirement of real-time monitoring of an anaerobic digester. Validation of the system developed has been assessed by application of the procedure to sludge samples from various origins, and comparative results with gas chromatography analyses showed satisfactory correlation (R-2 > 0.98). (C) 2013 Elsevier B.V. All rights reserved

Développement d'une méthode alternative pour la caractérisation fonctionnelle par spectrofluorescence des composés organiques dissous dans les écosystèmes

L étude du devenir des contaminants organiques et minéraux dans la biosphère nécessite une caractérisation physico-chimique du milieu récepteur afin d évaluer les cinétiques de transport et de migration de ces contaminants. Parmi les constituants des milieux récepteurs, la matière organique dissoute (MOD) -terme plutôt réservée aux sols- et la matière organique naturelle (MON) -terme plutôt réservées aux eaux- représentent une des composantes essentielles qui va régir la migration, le transport et le devenir de ces contaminants. Ces termes intégrateurs recouvrent une multitude de familles de molécules organiques qui présentent un nombre important et une diversité de groupements fonctionnels qui leur procurent un caractère très réactif, dépendant de leurs propriétés intrinsèques (solubilité, hydrophobicité, taille, capacité complexante, pKa, toxicité). L objectif de ce travail de recherche est d apporter une contribution à la caractérisation de cette MOD en s intéressant plus particulièrement à la détermination et au dosage des groupements fonctionnels acides carboxyliques, thiols et amines. La méthodologie retenue repose sur la mise au point de protocoles analytiques alternatifs basés sur une détection par fluorescence des groupements fonctionnels ciblés, après une étape préalable de dérivation spécifique. Ce mémoire présente les critères qui ont guidé les choix des réactifs utilisés pour la dérivation et la détection post-dérivation par fluorescence des groupements fonctionnels et l optimisation des conditions réactionnelles (pH, concentrations des réactifs, ratios des réactifs en fonction des volumes d échantillons, cinétiques de réaction) par la mise en oeuvre de plans de criblage, de plans d expériences et de désirabilité. Il présente ensuite la mise au point de kits d analyse prêt-à-l emploi pour l analyse sur site des composés carboxyliques, thiols et amines, et d un système en flux totalement automatisé pour l analyse en continu pour le suivi des Acides Gras Volatils (AGV). Enfin, il présente les essais concluants obtenus avec des échantillons réels provenant de matrices environnementales très variées (boues de stations d épuration, sols naturels et compostés, bambous, ) ainsi que les caractéristiques analytiques des différents systèmes mis au point.The study of the fate and behaviour of organic and mineral pollutants in the biosphere needs a physico-chemical characterization of the receiving medium in order to assess transport and migration kinetics of these contaminants. Among constituents of receiving media, dissolved organic matter (DOM) -term more often used for soils- and natural organic matter (NOM) -term more often used for waters- represent one of the essential components which regulate migration, transport and fate of these pollutants. These integrative terms cover a multitude of organic molecule families which present a large number and variety of functional groups that give them a very reactive character dependent on their intrinsic properties (solubility, hydrophobicity, size, complexation ability, pKa, toxicity). This research work aims to make a contribution to the characterization of DOM by focusing more specifically to the determination and analysis of carboxylic acid, thiol and amine functional groups. The methodology retained lies on the design of alternative analytical protocols based on a fluorimetric detection of targeted functional groups, following a step of a specific derivatization procedure. This report presents the criteria that have driven choice of reagents used for the derivatization and post-derivatization fluorimetric detection of functional groups, and the optimization of reactional conditions (pH, amount of reagents, ratios of reagents according to sample volumes, reaction kinetics) by use of screening procedures, experimental and desirability designs. It presents then the design of ready-to-use microplate assays for on-site analysis of carboxylic, thiol and amine compounds, and of a fully automated flow-system for the on-line analysis of Volatile Fatty Acids (VFA). Finally, it presents the conclusive trials obtained with real samples coming from various environmental matrices (sewage sludges from wastewater treatment plants, natural and composted soils, bamboos ) along with the analytical features of the different analysis system developed.AIX-MARSEILLE1-BU Sci.St Charles (130552104) / SudocSudocFranceF

Degradation of Organic UV filters in Chlorinated Seawater Swimming Pools: Transformation Pathways and Bromoform Formation

International audienceOrganic ultraviolet (UV) filters are used in sunscreens and other personal-care products to protect against harmful effects of exposure to UV solar radiation. Little is known about the fate of UV filters in seawater swimming pools disinfected with chlorine. The present study investigated the occurrence and fate of five commonly used organic UV filters, namely dioxybenzone, oxybenzone, avobenzone, 2-ethylhexyl-4-methoxycinnamate, and octocrylene, in chlorinated seawater swimming pools. Pool samples were collected to monitor the variation of UV filter concentrations during pool opening hours. Furthermore, laboratory-controlled chlorination experiments were conducted in seawater spiked with UV filters to investigate the reactivity of UV filters. Extracts of chlorination reaction samples were analyzed using high-resolution mass spectrometry and electron-capture detection to identify the potentially formed byproducts. In the collected pool samples, all the UV filters except dioxybenzone were detected. Chlorination reactions showed that only octocrylene was stable in chlorinated seawater. The four reactive UV filters generated brominated transformation products and disinfection byproducts. This formation of brominated products resulted from reactions between the reactive UV filters and bromine, which is formed rapidly when chlorine is added to seawater. Based on the identified byproducts, the transformation pathways of the reactive UV filters were proposed for the first time. Bromoform was generated by all the reactive UV filters at different yields. Bromal hydrate was also detected as one of the byproducts generated by oxybenzone and dioxybenzone

In situ complexation versus complex isolation in synthesis of ion imprinted polymers

International audienceIn this study, the object is to prove that isolation of complexes made by varying the metal/ligand ratio (in situ complexation) yields similar polymer characteristics, metal binding and selectivity results as polymers synthesized by isolating the complex by precipitation. Complexation between nickel and the N-(4-vinylbenzyl)-2-(aminomethyl)pyridine (Vbamp) monomer was studied in dimethyl sulfoxide (DMSO) and in a DMSO-methanol mixture (50:50, v/v) at 80 °C using a Ni(NO 3) 2 ·6H 2 O salt as the nickel source. According to the results, the three nickel/Vbamp complexes could be selectively obtained using specific conditions: for [Ni(Vbamp)] 2 + the Ni/ Vbamp ratio in DMSO was 1.08, for [Ni(Vbamp) 2 ] 2 + the Ni/Vbamp ratio DMSO-methanol (50:50, v/v) was 0.49 and for [Ni(Vbamp) 3 ] 2 + the Ni/Vbamp ratio in DMSO was 0.3. Ion-imprinted polymers (IIPs) were prepared either with [Ni(Vbamp)](NO 3) 2 , [Ni(Vbamp) 2 ](NO 3) 2 , or [Ni(Vbamp) 3 ](NO 3) 2 complexes as the template. IIP with a [Ni(Vbamp) 3 ] 2 + complex, isolated by precipitation prior to polymerization, was also prepared. The results demonstrated that surface properties, nickel binding and selectivity properties were similar for both kind of IIPs – prepared by in situ complexation or isolation of the complex prior to polymer synthesis. Selectivity coefficients of nickel toward zinc for IIPs with [Ni(Vbamp)] 2 + , [Ni(Vbamp) 2 ] 2 + and [Ni(Vbamp) 3 ] 2 + templates were close to 1038, 1441 and 1463, respectively