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International audience; Analysis 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.

The mutagenicity of four organic UV filters namely oxybenzone (benzophenone-3), dioxybenzone (benzophenone-8), avobenzone, and octyl methoxycinnamate, in chlorinated bromide-rich water (artificial seawater) was investigated. Mutagenicity was evaluated using Ames test in Salmonella typhimurium TA98 without S9 mix. Chemical analysis using high-resolution mass spectrometry was carried out to elucidate the mutagenic transformation products. Among the studied UV filters, only dioxybenzone exhibited a clear mutagenic activity following chlorination in seawater at ratio 1:10 (UV filter:chlorine). In contrast, no mutagenic activity was detected when chlorine was added at higher doses (ratio 1:1000). High-resolution mass spectrometry analysis showed that mutagenic extracts contained several brominated transformation products of dioxybenzone. Time course analysis of the transformation products at increasing chlorine doses showed that they were unstable and disappeared more quickly at higher chlorine doses. This instability explained the absence of mutagenic activity of dioxybenzone when 1000-fold excess chlorine was added, as no transformation products were detected. Relevance of these findings to the context of swimming pool is discussed. Further investigations taking into consideration the mutagenicity of not only the intermediate transformation products but also the final disinfection byproducts are needed to determine the overall impact of high levels of chlorine on the overall mutagenicity. This study highlights the importance of considering the reactivity of organic UV filters and their transformation products in disinfected recreational waters when sunscreen formulations are prepared.

International audience; A new procedure is described for the determination of Hg 2+ ions in water samples. A Rhodamine based fluorescent sensor was synthesized and the experimental conditions were specifically optimized for application to environmental samples, which requires low detection limits and high selectivity in competitive experiments with realistic concentrations of other metal ions. Incorporation of a Rhodamine-6G fluorophore to a previously described sensor and optimization of the buffer system (detection with acetic acid at pH 5.25) enabled significant enhancement of the sensitivity (detection limit = 0.27 µg.L-1) and selectivity. The optimized procedure using high-throughput microplates has been applied to tap and river waters with good results.

Several brominated disinfection by-products (DBPs) are formed in chlorinated seawater pools, due to the high concentration of bromide in seawater. UV irradiation is increasingly employed in freshwater pools, because UV treatment photodegrades harmful chloramines. However, in freshwater pools it has been reported that post-UV chlorination promotes the formation of other DBPs. To date, UV-based processes have not been investigated for DBPs in seawater pools. In this study, the effects of UV, followed by chlorination, on the concentration of three groups of DBPs were investigated in laboratory batch experiments using a medium-pressure UV lamp. Chlorine consumption increased following post-UV chlorination, most likely because UV irradiation degraded organic matter in the pool samples to more chlorine-reactive organic matter. Haloacetic acid (HAA) concentrations decreased significantly, due to photo-degradation, but the concentrations of trihalomethanes (THMs) and haloacetonitriles (HANs) increased with post-UV chlorination. Bromine incorporation in HAAs was significantly higher in the control samples chlorinated without UV irradiation but decreased significantly with UV treatment. Bromine incorporation was promoted in THM and HAN after UV and chlorine treatment. Overall, the accumulated bromine incorporation level in DBPs remained essentially unchanged in comparison with the control samples. Toxicity estimates increased with single-dose UV and chlorination, mainly due to increased HAN concentrations. However, brominated HANs are known in the literature to degrade following further UV treatment.

International audience; Organic 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.

International audience; 15 The present paper reports the development and the application of a microplate assay for the fast 16 and individual determination of thiols and sulfides. The method is based on the reaction of ethyl 17 propiolate with thiols and sulfides, yielding thioacrylates absorbing in the UV range. 18 Thioacrylate generated by derivation of sulfide with EP presents a bathochromic shift of 19 maximal absorbance wavelength of 16 nm compared to thioacrylates formed with thiols. EP 20 concentration, reaction time and derivatization pH were carefully optimized in order to 21 separately quantify thiols and sulfides using a spectral deconvolution procedure in 15 minutes. 22 The detection limits were 0.6 and 2.8 µM (63.7 and 92.4 µg.L-1) for mercaptopropionic acid 23 (used as reference thiol compound for calibration) and dissolved hydrogen sulfide respectively. 24 Non-thiol sulfur compounds (methionine, sulfates and sulfites) or other nucleophile compound 25 did not display any interference in the determination of MPA or sulfides. Interference from 26 metals was suppressed with application of a reduction step with TCEP and DTPA. Finally, the 27 method has been successfully applied to the analysis of raw and treated wastewater. 28 29

International audience; This study highlights the trace metal and metalloid (TMM) accumulation in Rosmarinus officinalis L. and its chemical responses when exposed to high levels of contamination. R. officinalis individuals growing along a gradient of mixed TMM soil pollution, resulting from past industrial activities, were analysed. Several plant secondary metabolites, known to be involved in plant tolerance to TMM or as a plant health indicator, were investigated. The levels of thiol compounds and phytochelatin precursors (cysteine and glutathione) in the shoots were measured in the laboratory, while a portable non-destructive instrument was used to determine the level of phenolic compounds and chlorophylls directly on site. The level of Pb, As, Sb and Zn contaminations within the soil and plants was also determined.The results highlighted a decrease of TMM translocation with increases of soil contamination. The concentration of TMM in the shoots followed the Mitscherlich equation and reached a plateau at 0.41, 7.9, 0.37, 51.3 mg kg−1 for As, Pb, Sb and Zn, respectively. In the shoots, the levels of thiols and phenols were correlated to concentrations of TMM. Glutathione seems to be the main thiol compounds involved in the tolerance to As, Pb and Sb. Phenols indices, using non-destructive measurements, may be considered as an easy way to establish a proxy to estimate the TMM contamination level of the R. officinalis shoots. The study highlights metabolic processes that contribute to the high potential of R. officinalis for phytostabilisation of TMM in contaminated areas in the Mediterranean.

International audience; The spatial distribution patterns, origins and environmental and health risks of metal trace elements (As, Cd, Co, Cr, Cu, Ni, Pb, Zn) have been analyzed through the spiking and the analysis of 84 soils sampled in the region of Arzew (Algeria). This city gathers one of the biggest petroleum harbors of Algeria and gathers in the same platform several industries, coexisting with residential and agricultural areas. The mean concentration of all the metals studied exceed their corresponding backgrounds levels and/or exceed the ecological Predicted No effect Concentration (PNEC) values. The geo-accumulation and the potential ecological risk indices indicate a low to moderate risk for As, Co, Cu, Ni and Zn, and a moderate to considerable risk for Cr and Pb. According to the health risk assessment results, the carcinogenic risks due to Cr exceed the acceptable level in all the functional areas, and when considering combined effects of metals, the hazard index obtained show a high potential carcinogenic risk to the local children.

International audience; Chlorination of seawater is one of the most effective technologies for industrial biofouling control. However, chlorination leads to the formation of halogenated chlorination byproducts (CBPs) associated with potential risks to environmental and human health. The present study investigated the occurrence and distribution of CBPs in the Gulf of Fos, a semi-enclosed bay where chlorinated effluents of multiple industrial plants are discharged. Seawater samples (surface and bottom) were collected at 24 sampling stations, with some near industrial outlets and others dispersed throughout the bay. Sediment samples were also collected at 10 sampling stations. Physicochemical parameters including water temperature, pH, salinity, bromide content, and free and total residual oxidant were determined. Several chemical classes of CBPs including trihalomethanes, haloacetic acids, haloacetonitriles, trihaloacetaldehydes, and halophenols were analyzed. Bromoform was the most abundant CBP in seawater, and it was detected at most of the sampling stations of the bay with highest concentrations occurring near the industrial effluent outlets. Dibromoacetic acid was the second most abundant CBP at most of the sites followed by dibromoacetonitrile. Other detected CBPs included tribromoacetic acid, bromochloroacetonitrile, and bromal hydrate. To our knowledge, the concentration of the latter CBP was reported here for the first time in the context of industrial seawater chlorination. In sediments, two bromine-containing halophenols (2-chloro-4-bromophenol and 2,4,6-tribromophenol) were detected at two sampling stations. Ecotoxicological assays and risk assessment studies based on the detected environmental concentrations are warranted to elucidate the impacts of marine CBP contamination.

In this paper, a new thin-layer chromatography (TLC) method for the determination of individual volatile fatty acids (VFAs) is presented. The experimental procedure is based on the derivatization of VFAs with activating agents and a naphthalene-based amine to form an amide derivative, followed by fast TLC separation of these VFA derivatives and visualization with phosphomolybdic acid at room temperature. Quantification is then performed by densitometric measurements using free software after taking TLC pictures in a home-made black box for homogeneous and reproducible lighting of the plates. Optimization of the experimental conditions enables fast determination (20 minutes for 3 samples) of VFAs with detection limits (1.5–2.5 mg L−1) and relative standard deviations (4.6–6.7%) satisfactory enough for our analytical purpose using low-cost instruments with easy to find materials and software. The protocol was then applied to real samples (aqueous extracts of sewage sludge composts) and the results were compared with gas chromatography analysis with good agreement between the two methods.

International audience; Water chlorination is the most widely used technique to avoid microbial contamination and biofouling. Adding chlorine in bromide-rich waters leads to the rapid oxidation of bromide ions and leads to the formation of brominated disinfection by products (bromo-DBPs) that exert adverse effects on various biological models. Bromo-DBPs are regularly encountered within industrialized embayments, potentially impacting marine organisms. Of these, bromoform, tribromoacetic acid and tribromophenol are among the most prevalent. In the present study, we tested the potential toxicity and genotoxicity of these disinfection by-products, using sea urchin, Paracentrotus lividus, embryos. We highlighted that tribromophenol showed higher toxicity compared to bromoform and tribromoacetic acid. Furthermore, a synergistic effect was detected when tested in combination. Pluteus cells exposed for 1h to mixtures of DPBs at several concentrations demonstrated significant DNA damage. Finally, when compared to a non-exposed population, sea urchins living in a bromo-DPB-polluted area produced more resistant progenies, as if they were locally adapted. This hypothesis remains to be tested in order to better understand the obvious impact of bromo-DBPs environments on marine wildlife.

International audience; 9 In this paper, a new spectrofluorimetric method for the determination of nitrate in aqueous 10 compost extracts is presented. The microplate procedure is based on the reduction of nitrate 11 to ammonium by means of Zn powder under acidic conditions and the following derivatization 12 of ammonium with o-phtaladehyde (OPA) and N-acetylcysteine (NAC) to give a fluorescent 13 derivative. Optimization work allowed performing the reduction in 30 min on a small sample 14 volume (150 µL) and using a little quantity of metal (20 mg). The use of strong acids is also 15 avoided. Excellent limit of detection was achieved (1.3 µM = 0.08 mg.L-1 NO3-) along with good 16 precision levels (4.2 and 14.3 % for 50 and 5 µM, respectively) and a satisfactory linear 17 dynamic range (4-100 µM). A good agreement between data coming from our method and 18 from ion-exchange chromatography was found on real compost samples, indicating a good 19 level of accuracy. 20 21 22

International audience; Chlorination is one of the most widely used techniques for biofouling control in large industrial units, leading to the formation of halogenated chlorination by-products (CBPs). This study was carried out to evaluate the distribution and the dispersion of these compounds within an industrialised bay hosting multiple chlorination discharges issued from various industrial processes. The water column was sampled at the surface and at 7 m depth (or bottom) in 24 stations for the analysis of CBPs, and muscle samples from 15 conger eel (Conger conger) were also investigated. Temperature and salinity profiles supported the identification of the chlorination releases, with potentially complex patterns. Chemical analyses showed that bromoform was the most abundant CBP, ranging from 0.5 to 2.2 μg L− 1 away from outlets (up to 10 km distance), and up to 18.6 μg L− 1 in a liquefied natural gas (LNG) regasification plume. However, CBP distributions were not homogeneous, halophenols being prominent in a power station outlet and dibromoacetonitrile in more remote stations. A seasonal effect was identified as fewer stations revealed CBPs in summer, probably due to the air and water temperatures increases favouring volatilisation and reactivity. A simple risk assessment of the 11 identified CBPs showed that 7 compounds concentrations were above the potential risk levels to the local marine environment. Finally, conger eel muscles presented relatively high levels of 2,4,6-tribromophenol, traducing a generalised impregnation of the Gulf of Fos to CBPs and a global bioconcentration factor of 25 was determined for this compound.

In this paper, a new spectrofluorimetric method is proposed for the fast, simple, and accurate determination of trace resorcinol in the microplate format (high-throughput screening). The analytical method is based on the formation of a coumarin derivative with methyl acetoacetate via a Pechmann condensation reaction. Experimental conditions have been optimized, and excellent analytical performances have been achieved with a limit of detection of 0.46 μg L − 1 , a wide linear range between 1.5 and 1000 μg L − 1 and a relative standard deviation of 2.01% ( n = 10). This method is remarkably specific for resorcinol compared to other phenols and hydroxyphenols and suffers from low interferences from other potential matrix components. The proposed protocol was finally applied and validated on real samples such as wastewater or pharmaceutical/cosmetic samples.

International audience; Oxybenzone (2-hydroxy-4-methoxyphenone, benzophenone-3) is one of the UV filters commonly found in sunscreens. Its presence in swimming pools and its reactivity with chlorine has already been demonstrated but never in seawater swirnrning pools. In these pools, chlorine added for disinfection results in the formation of bromine, due to the high levels of bromide in seawater, and leads to the formation of brominated disinfection byproducts, known to be more toxic than chlorinated ones. Therefore, it seems important to determine the transformation products of oxybenzone in chlorinated seawater swimming pools; especially that users of seawater swimming pools may apply sunscreens and other personal-care products containing oxybenzone before going to pools. This leads to the introduction of oxybenzone to pools, where it reacts with bromine. For this purpose, the reactivity of oxybenzone has been examined as a function of chlorine dose and temperature in artificial seawater to assess its potential to produce trihalomethanes and to determine the byproducts generated following chlorination. Increasing doses of chlorine and increasing temperatures enhanced the formation of bromoform. Experiments carried out with excess doses of chlorine resulted in the degradation of oxybenzone and allowed the determination of the degradation mechanisms leading to the formation of bromoform. In total, ten transformation products were identified, based on which the transformation pathway was proposed.

International audience; An analytical chemical method has been developed for determination of beta-hydroxymyristic acid (beta-HMA), a component of lipopolysaccharides (LPSs/endotoxins) in dialysis water. In our investigation, the beta-HMA component was used as a chemical marker for endotoxin presence in dialysis water because it is available in the molecular subunit (lipid A) and responsible for toxicity. It is the most abundant saturated fatty acid in that subunit. The developed method is based on fluorescence derivatization with 4-nitro-7-piperazino-2,1,3-benzoxadiazole (NBD-PZ). A high-performance liquid chromatographic separation of the beta-HMA derivative was achieved using an octadecyl silica column in gradient elution. A wide dynamic range of beta-HMA was tested and a calibration curve was constructed with accuracy of 90% and variability of less than 10%. The limits of detection and quantification obtained were 2 and 51 mu M, respectively. The developed method was applied to detect endotoxins in dialysis water by alkaline hydrolysis of LPS using NaOH (0.25 M) at 60 degrees C for 2 h. After hydrolysis, free acid was detected as its NBD-PZ derivative using high-performance liquid chromatography/mass spectrometry (HPLC/MS). Good recovery rates ranging from 98 to 105% were obtained for beta-HMA in dialysis water. (C) 2014 Elsevier Inc. All rights reserved.

International audience; Abbreviations: Br-DPBs (brominated disinfection by-products); CHBr 3 (bromoform); CHCl 3 (chloroform), CHCl 2 Br (dichlorobromomethane), CHClBr 2 (dibromochloromethane); Clf (free residual chlorine); NPOC (Non Purgeable Organic Carbon); PCA (Principal Component Analysis); T water (temperature of water); T air (temperature of air); TTHMs (total trihalomethanes = sum of THM-4); Abstract Water and air quality of eight seawater swimming pools using chlorine disinfection was measured during four sampling campaigns, spread on one full-year, and in four thalassotherapy centres located in Southeast of France. Concentrations of trihalomethanes (THMs) in air and in water as well as concentrations of parameters, including non purgeable organic carbon (NPOC), free residual chlorine (Cl f), pH, Kjeldhal Nitrogen (KN), salinity, conductivity, bromide ions and, water and air temperature, were measured. Water and air samples were collected in triplicates morning-at the opening of the pools-, noon and night-at the closing of the pools-, in summer and winter. Data analysis was performed by Principal Component Analysis (PCA) and rotated component matrix, from both data quality and other parameters such as TOC, aromaticity (UV 254), pH, hygrometry, and free residual chlorine (Cl f). This statistical analysis demonstrates a high correlation between TOC, Cl f and UV 254 and THM levels found in air and water, particularly for the major ones (CHBr 3 in water : 300.0 µg.L-1 mean, 1029.0 µg.L-1 maximum; CHBr 3 in air : 266.1 µg.m-3 mean, 1600.0 µg.m-3 maximum, and CHClBr 2 in water: 18.9 µg.L-1 mean, 81.0 µg.L-1 maximum; CHClBr 2 in air : 13.6 µg.m-3 mean, 150.0 µg.m-3 maximum). These high levels of bromoform (CHBr 3) are particularly worrisome in such health institutions, even these levels do not exceed the Permissible Exposure Limit (PEL) of 5 mg.m-3 as an 8 hour time-weighted average currently 2 fixed by various administrations, such as Occupational Safety and Health Administration (OSHA).

International audience; An undesirable consequence of disinfection is the formation of chemical contaminants known as disinfection byproducts (DBPs). Chronic exposure to DBPs has been linked to adverse health effects. The occurrence of DBPs in chlorinated pools filled with seawater (such as thalassotherapy pools and pools in spas) has received little attention so far. The present study evaluated the speciation and levels of disinfection byproducts in indoor swimming pools filled with seawater and treated with chlorine. Water and air samples were collected from three indoor swimming pools located in Southern France. Several classes of DBPs including trihalomethanes, haloacetic acids, haloacetonitriles, and trihaloacetaldehydes were analyzed in water. Halogenated volatile organic compounds were analyzed in air. Extractable organic halide (EOX) contents were determined using combustion micro-coulometry system. The speciation of DBPs identified in the three pools was predominantly brominated. The mean (arithmetic) concentration of bromoform, dibromoacetic acid, tribromoacetic acid, dibromoacetonitrile and bromal hydrate in the three pools were 79.2, 72.9, 59.9, 26.9 and 10.0 µg/L, respectively. By weight, HAAs represented the most abundant chemical class followed by THMs. In air, bromoform was the most abundant THM occurring at a mean concentration of 133.2 µg/m 3 in the three pools. The mean EOX level was 706 µgCl-/L for the three pools. In average, the quantified DBPs accounted for only 14% of EOX, thus 86% of EOX remained unknown. Further research is warranted to identify the unknown DBPs.

International audience; Disinfection 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.

International audience; 10 The development of 3D printing in recent years opens up a vast array of possibilities in the field 11 of flow analysis. In the present study, a new 3D-printed flow system has been developed for 12 the selective spectrophotometric determination of lead in natural waters. This system was 13 composed of three 3D-printed units (sample treatment, mixing coil and detection) that might 14 have been assembled without any tubing to form a complete flow system. Lead was determined 15 in a two-step procedure. A preconcentration of lead was first carried out on TrisKem Pb Resin 16 located in a 3D-printed column reservoir closed by a tapped screw. This resin showed a high 17 extraction selectivity for lead over many tested potential interfering metals. In a second step, 18 lead was eluted by ammonium oxalate in presence of 4-(2-pyridylazo)-resorcinol (PAR), and 19 spectrophotometrically detected at 520 nm. The optimized flow system has exhibited a linear 20 response from 3 to 120 µg.L-1. Detection limit, coefficient of variation and sampling rate were 21 evaluated at 2.7 µg.L-1 , 5.4% (n=6) and 4 sample.h-1 , respectively. This flow system stands out 22 by its fully 3D design, portability and simplicity for low cost analysis of lead in natural waters. 23 24

International audience; Inorganic chloramines are disinfection by-products resulting from the unwanted reaction between chlorine used as disinfectant in swimming pools and nitrogenous compounds brought by bathers. This parameter (total chloramines or combined chlorine) is currently measured on site by a colorimetric method that does not allow to measure only inorganic chloramines. In this paper, a multi-syringe chromatography system combined with a post column derivatization is applied for the first time for the specific detection of the three individual inorganic chloramines (monochloramine, dichloramine and trichloramine). These latter ones are separated using a low-pressure monolithic C18 column, and separately detected after a post-column reaction with the chromogenic reagent ABTS (2,2'-azino-bis-(3-ethyl-benzothiazoline)-6-sulfonic acid-diammonium salt). Development of two ABTS reagents provides discrimination of chlorine and monochloramine that are not separated on the column. Optimization of the experimental conditions enables determination of inorganic chloramines with very good detection limits (around 10 µg eq.Cl2 L-1) without interferences from other chlorinated compounds such as organic chloramines or free available chlorine. The validation of the whole procedure has been successfully applied to real swimming pools samples.

International audience; In 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.

International audience; Water disinfection treatments result in the formation of disinfection byproducts (DBPs) that have been linked to adverse human health outcomes including higher incidence of bladder and colorectal cancer. However, data about the genotoxicity of DBPs is limited to only a small fraction of compounds. Chloral hydrate (CH) and bromal hydrate (BH) are two trihaloacetaldehydes commonly detected in disinfected waters, but little is known about their genotoxicity, especially BH.We investigated the genotoxicity of CH and BH using a test battery that includes three in vitro genotoxicity assays.We conducted the Ames test using Salmonella bacterial strains TA97a, TA98, TA100 and TA102, and the alkaline comet assay and the micronucleus test both using Chinese hamster ovary cells. We carried out the tests in the absence and presence of the metabolic fraction S9 mix.CH did not exhibit statistically significant genotoxic effects in any of the three assays. In contrast, BH exhibited mutagenic activity in the Salmonella strain TA100 and induced statistically significant DNA lesions in CHO cells as appeared in the comet assay. The genotoxic potential of BH in both assays decreased in the presence of the metabolic fraction S9 mix. BH did not induce chromosomal damage in CHO cells.Our results show that BH exhibited genotoxic activity by causing mutations and primary DNA damage while CH did not induce genotoxic effects. Our findings highlight concerns about the higher genotoxicity of brominated DBPs in comparison to their chlorinated analogues.

In this paper, an on-line spectrofluorimetric system is proposed for a simple, rapid and accurate measurement of 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 a spectrofluorimetric detection of the corresponding amide. The analytical procedure is automated with a flow analysis technique, coupling multisyringe (MSFIA) and multi-pumping (MPFS) methods. Operative conditions have been investigated with a special attention paid to the activation and amidation steps and to the liquid-liquid extraction of the derivatized final product. Fluorescence intensities (lambda(em)=335 nm, lambda(ex)=395 nm) were found to be proportional to the concentration of VFA, expressed as acetic equivalent, in the range 19-1000 mg L(-1), with a detection limit (3sigma) of 5.1 mg L(-1). Our results showed a good selectivity for VFA as compared to other organic and inorganic compounds usually found in sewage sludges. Validation of the on-line system developed has been assessed by application of the procedure to aqueous samples originating from sewage sludge treatment plants. The results were in good agreement with ion chromatography measurements.

Sediments may act as a sink for nutrients and trace metals after deposition. It may pose a risk for surface water quality and ecosystem health when environmental changes lead to release nutrients and trace metals stored in these sedimentary stocks. The management of the quality of freshwater systems needs to understand the processes of remobilisation of these stocks. This mobility is dependent on the erosion, on the interstitial diffusion of the mobile phases and on the bioturbation. These mechanisms depend on early diagenetic processes that condition the physical and biogeochemical properties of the sedimentary column. These properties are mainly influenced by the redox transformations resulting from oxidation of the organic matter by the microbial activity. These reactions generate vertical profiles of nutrient and metals concentrations along the sedimentary column. This paper aims to propose a modelling and an experimental protocol to determine vertical profiles of nutrients and trace metals in saturated sedimentary columns of freshwater systems. The modelling approach is based on a coupling between bio-geochemical processes [1], interstitial diffusion [2, 3] and solid-liquid exchanges. The main originality of the model is the pH determination that is directly calculated from the pore water concentrations of the ionic species. As illustration, this paper presents an application to natural sediment cores collected in the Durance Rivers.

New materials for chelating solid-phase extraction have been prepared by grafting of salicylic acid and derivatives on poly(styrene-co-divinylbenzene) based sorbents. These sorbents are either resin bead-shaped Amberlite® XAD-4 or membrane disk-shaped Empore™ SDB-XC. Grafting has been achieved via –N N– spacer. The grafted ligands are salicylic acid (SA), its dimer form methylenedisalicylic acid (MDSA) and trimer form aurintricarboxylic form (ATA) in order to study the influence of multi-functionalization on chelating properties. Grafting scheme was validated on a model molecule (4-ethylaniline) for optimisation of experimental conditions. The resulting sorbents have been characterised by FTIR, Py-GC/MS analysis and 13 C CP-MAS NMR. Grafting rates are higher for SA (25–38%) than for MDSA (16–17%) and ATA (9%), still the number of SA entities remains almost constant. Metallic sorption abilities of the two new sorbents – determined by ICP-AES – have been succcessfully assessed by means of flow-through experiments with synthetic solution of multielement cations (Cd2+, Co2+, Cu2+, Mn2+, Ni2+, Pb2+, Zn2+, Fe2+ and Al3+). It evidenced the influence of the PTFE matrix, contained in Empore disks, for acidic pH. Finally, complexing capacities for Fe(III) were found to be higher for membranes (13.4 ± 0.7 for SA) than for resins (11.6 ± 0.6): this allows to consider grafted polymer membranes as competitive materials for SPE applications.

International audience; Sediment-water interactions play an important role in influencing the water quality of aquatic systems. Water quality management of freshwater systems needs to take into account this behaviour, which depends largely on early diagenetic processes that condition the physical and biogeochemical properties of the sediment. Among these processes, the redox transformations resulting from the oxidation of organic matter by the microbial activity have a major influence on the biogeochemical properties of sedi-ments. In particular, these reactions condition the vertical profiles of nutrient concentrations, pH and metals along the sedimentary column. This paper presents a method which couples both experimental and modelling approaches in order to characterise and analyse the biogeochemistry of freshwater sediments. The modelling approach is based on a coupling between biogeochemical processes and interstitial diffusion. As pore water pH influences the behaviour of the biogeochemical species, we have extended these models to allow for the calculation of pH by taking into account the inventory of protons consumed or produced by different biogeochemical reactions. In parallel, an analytical protocol has been developed to obtain vertical distributions of the main physicochemical parameters in natural sediments cores. To illustrate this approach, we apply our method to sediments cores sampled in the Durance, a river in the south-east of France.

This paper aims to improve the understanding of organic amendments distribution on different fractions of soil organic matter (SOM) and the knowledge of processes controlling the temporal evolution of organic matter (OM) in the first layer of a calcareous soil of two adjacent plots, one control and one treated with 3 kg m − 2 of organic amendment. An appropriate fractionation procedure of SOM, consisting in sequential extractions by water, hydrochloric acid, sodium hydroxide and potassium pyrophosphate extractions, was applied. Dissolved organic carbon (DOC), UV and fluorescence spectroscopic properties of organic matter reveal quantitative and qualitative aspects. Spectral indexes such as SUVA 254 (specific UV absorbance), E 2 /E 3 and FI (fluorescence index) were used to examine annual changes of SOM in the different fractions. Extractions with pyrophosphate, and in a lesser amount with sodium hydroxide, represented the major part of DOC, for both control and treated soils. Yields of sequential extractions ranged from 16.1% to 16.4% of TOC for these two soils. Compost inputs resulted in evolution of quantitative and qualitative results, especially for water extractable organic matter (WEOM) and pyrophosphate extracts mainly during the first 3 months of this field experiment. Study of annual changes of DOC, SUVA 254 and E 2 /E 3 index values in treated soil indicated a priming effect during the weeks after compost spreading, in relation with a revitalizing effect of microbial activity. Contributions of organo-mineral interactions and rainfall regulated WEOM amount throughout the year, and the activity of microbial communities in soil seemed to play a significant role on WEOM production. FI index values demonstrated microbial origin for WEOM, and for OM extracted either with acid or with sodium hydroxide. At the contrary, pyrophosphate extracts revealed that OM came essentially from terrestrial origin, which corresponds to the most complex and aromatic compounds. It was found that sodium hydroxide extracted less aromatic SOM, but higher molecular weight compounds. 3D fluorescence spectra revealed the presence of four main types of fluorophores according to the different extracts: humic, fulvic and marine-like compounds (A, C and M) common to all extracts, and lignin-like compounds (H) specific to pyrophosphate extracts only in treated soil at the beginning of the experiment due to initial compost effect. PCA on quantitative and qualitative data for WOEM fraction revealed essentially that meteorological aspects, with temperature and precipitation variations, were an important parameter over the year of experimentation, and that compost input impacted significantly WEOM amounts at the beginning of the experiment.

International audience; A new analytical method was developed for on-line monitoring of residual coagulants (aluminium and iron salts) in potable water. The determination was based on a sequential procedure coupling an extraction/enrichment step of the analytes onto a modified resin and a spectrophotometric measurement of a surfactant-sensitized binary complex formed between eluted analytes and Chrome Azurol S. The optimization of the solid phase extraction was performed using factorial design and a Doehlert matrix considering six variables: sample percolation rate, sample metal concentration, flow-through sample volume (all three directly linked to the extraction step), elution flow rate, concentration and volume of eluent (all three directly linked to the elution step). A specific reagent was elaborated for sensitive and specific spectrophotometric determination of Al(III) and Fe(III), by optimizing surfactant and ligand concentrations and buffer composition. The whole procedure was automated by a multisyringe flow injection analysis (MSFIA) system. Detection limits of 4.9 and 5.6 μg L−1 were obtained for Al(III) and Fe(III) determination , respectively, and the linear calibration graph up to 300 μg L−1 (both for Al(III) and Fe(III)) was well adapted to the monitoring of drinking water quality. The system was successfully applied to the on-site determination of Al(III) and Fe(III) at the outlet of two water treatment units during two periods of the year (winter and summer conditions).

Chelating solid phase extraction is a method particularly adapted to the recovery of metallic ions in polluted waters. The principle consists in the partitioning of the analyte between the solution and a solid sorbent grafted by a ligand. Aromatic organic crosslinked copolymers, which are commercially available, permit to consider numerous ways of linking the ligand to the sorbent. In this way, the grafting of salicylic acid (SA) via a ketone bridge on Amberlite® XAD-4 resin has been previously achieved with success. Then the same grafting on Empore™ SDB-XC membrane was also considered. The yield obtained is 33%. The determination of complexing capacities highlights the fact that about 20% of the grafted complexing sites could efficiently retain metallic ions. For the first time, a ligand has been covalently linked to Empore™ SDB-XC membrane.

International audience; This paper describes an investigation of linear alkylbenzene sulfonates (LAS) and nonylphenol ethoxylates (NPEO) and their metabolites in the vicinity of the Marseille sewage outfall (wastewater treatment plant with a capacity of 1.860 million inhabitant equivalents, Northwestern Mediterranean, southeast of France). This analytical survey describes their occurrence in the subsurface and sea surface layers and investigates their possible fates in this marine environment. The results indicated the presence of LAS in both layers and up to 3 km from the discharge point, whereas the concentration of sulfophenyl carboxylic acids, which are the main metabolites of LAS, was only significant near the sewer outfall and in the surface layer. The NPEO were present only in minor quantities, especially near the discharge point, and no other selected metabolites were detected. The fate of the surfactants in question was then assessed by two types of experiments according to their potential means of degradation under natural conditions. Biodegradation assays were conducted according to a protocol defined by the United States Environmental Protection Agency (''Biodegradability in sea water, 835.3160''), with variations in the substrate input frequencies. Photodegradation experiments were carried out in a solar simulator reactor. These results demonstrated the low photodegradability and rapid primary biodegradation of LAS (with half-life times between 10.3 and 11.5 days) in the coastal area under study, although some LAS metabolites were more recalcitrant to biodegradation in this specific environment, which was also validated by linear alkylbenzene analysis in the two selected sediment stations.

A simple and rapid procedure for on-site qualitative and quantitative analysis of organic matter from discharges of municipal wastewater in seawater has been developed. This method is based on the knowledge of the UV signal of both seawater and anthropogenic absorbing matter and on the mathematical deconvolution of the sample spectrum using reference spectra. The main application is the estimation of TOC at the direct outlet of the discharge. This quantitative application is obviously limited by the nature of organic compounds, but the UV estimation allowed us to have an overview of the composition and evolution of organic matter into the polluted area. The application of this procedure has been carried out to study the wastewater dilution into an area receiving urban discharges. Experiments showed satisfactory analytical features with a range of TOC values from 75 to 1500 μM C, and the comparison of the results with those obtained by reference method presented a reasonable correlation (r2 = 0.9636) in the marine discharge. The results have also allowed us to quickly estimate the plume evolution at the sea surface and in depth. This alternative method could be integrated in a portable device for on-site analysis and multiplication of measurements for relevant results, or in a continuous flow analyser. © 2006 Taylor & Francis.

Background, Aim and Scope Most studies of sewage sludge disposal effects on plants have focused on high metal loadings. Less attention has been paid to plant responses to trace metal loadings below the recommended limit values. Materials and Methods: Here, a lysimetric experiment was conducted to assess the uptake, distribution and binding of trace metals by metal-induced, sulfhydryl-rich peptides (phytochelatins) in colza (Brassica napus, v. Jaguar) grown on a clayey, silty soil amended with a sewage sludge compost containing trace metal contents far below the recommended limit values established by French legislation. Chemical fractionation of unamended and sludge-amended soils was performed using a sequential extraction technique. Results: Copper concentrations in plant tissues were not affected by compost disposal. Its application at a single rate equivalent to 30 t/ha stimulated the growth of plants. Lead was not detectable in the plant material (< 1 mg g-1 dry wt.). Plants grown on the amended soil accumulated significantly more zinc than control plants. These phytochelatin complexes detected in leaves had a lower molecular weight than those extracted from roots. Those extracted from roots were composed of one type of phytochelatins (PCs) such as in leaves or a mixture of glutathione, PC2 and PC4. In comparison with control plants, sewage sludge compost application caused the synthesis of longer chain PCs in roots and in leaves. Furthermore, in comparison with control roots, glutathione and phytochelatin mixtures of higher molecular weight were detected in roots produced on the amended soil, whereas no significant increase in \total\ Cu and Zn content was observed in these organs after sludge application. Discussion: Compost application induces a significant increase in the proportion of the most labile forms of zinc and especially its pH 4.7 acid-soluble forms and, as a consequence, a higher accumulation of zinc in plants. Effects of copper are limited due to its strong affinity for humic substances and lead does not seem to be transported in any organ of plants. The presence of phytochelatins, even in plants grown on the unamended soil, proved the ability of colza to synthesize them in the presence of zinc and copper. Conclusions: These primary results seem to prove, on one hand, ability of colza (Brassica napus, v. Jaguar) to synthesize phytochelatins as well as in roots, in leaves and, on the other hand, the sensitivity of the PC induction as suggested by their identification in plants grown on the control soil. Synthesis of longer chain PCs in roots and in leaves, and formation of glutathione and phytochelatin mixtures in roots, are plant responses to sewage sludge compost application. Recommendations and Perspectives: Phytochelatin analysis is thus supposedly able to be one of the bioindicators that may be used as an ecotoxicological risk assessment of wastes. Due to its ability to synthesize phytochelatins, colza could be chosen as a plant test. Phytochelatin analysis could also be limited to roots (more sensitive than leaves). However, further experiments are needed. Quantitative analysis of phytochelatins had not been carried out due to insufficient amounts of pure phytochelatin standards, that had allow us to better study relationships between trace metal amounts to vegetal response.

For use in the solid-phase extraction of aluminium, a polystyrene-co-divinylbenzene) commercial resin (Amberlite(R)) XAD-4) was modified by grafting on salicylic acid. Anchorage of this ligand was achieved via a ketone bridge formed by Friedel-Crafts acylation. Because of the insolubility of the resin in common organic solvents, the synthesis scheme was optimized on the monomeric entity, benzoyl chloride, so that the purity of products could be assessed by common analytical techniques (gas chromatography-mass spectrometry (GC-MS), NMR and FTIR) and the yields improved. NMR spectroscopy indicated that the Friedel-Crafts acylation was performed in the position Para to the methoxy group. The synthesis scheme was then applied to the resin activated by an acid chloride function. Different steps of the modification were characterized by FTIR and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). The aluminium complexing capacity of the modified resin was evaluated and presence of complexed aluminium on the surface of the resin was assessed by scanning electron microscopy (SEM) and FTIR

International audience; This paper presents a simple, accurate and multi-sample method for the determination of proline in wines thanks to a 96-well microplate technique. Praline is the most abundant amino acid in wine and is an important parameter related to wine characteristics or maturation processes of grape. In the current study, an improved application of the general method based on sodium hypochlorite oxidation and o-phthaldialdehyde (OPA)-thiol spectrofluorometric detection is described. The main interfering compounds for specific proline detection in wines are strongly reduced by selective reaction with OPA in a preliminary step under well-defined pH conditions. Application of the protocol after a 500-fold dilution of wine samples provides a working range between 0.02 and 2.90 g L-1, with a limit of detection of 7.50 mg L-1. Comparison and validation on real wine samples by ion-exchange chromatography prove that this procedure yields accurate results. Simplicity of the protocol used, with no need for centrifugation or filtration, organic solvents or high temperature enables its full implementation in plastic microplates and efficient application for routine analysis of proline in wines. (C) 2013 Elsevier Ltd. All rights reserved.

The aim of this paper was to study the reaction pathway of the biodegradation and photodegradation of Linear Alkylbenzene Sulphonates (LAS), and to propose an analytical method, faster and more reliable, to predict the evolution of LAS in a sewage treatment plant. For this purpose, a 20mgL−1 LAS solution was treated on the one hand by a conventional biodegradation method using microorganisms, taken directly from aeration tanks of a sludge treatment plant, and on the other hand by UV radiation. This second method allows a rapid determination of LAS and its by-products by means of a UV signal treatment. This alternative method seems thus to be more suitable for on-line analysis.

International audience; The degradation of 4-chlorophenol (4-CP) by electrochemical oxidation in the presence of carbon black (CB) was studied in a laboratory reactor. This reactor consisted of a stack of Ti/Pt electrodes. After the mixing of the solution to be treated with CB, the slurry electrode thus obtained flows through the electrode grids. The reaction pathways and kinetics were studied by means of high performance liquid chromatography coupled with a UV detection, ionic chromatography coupled with a conductimetric detection and gaseous chromatography coupled with mass spectrometry. The reaction pathways were thus determined: after the C–Cl bond breaking, phenol and chloride ions were detected in the solution. The formation of 2-chlorophenol was also detected. The influence of the amount of CB used on the degradation yield of 4-CP was also studied. The full mineralization of 4-CP could be reached if CB was present in a sufficient amount and, in this case, no chlorine was detected.

International audience; Water disinfection technologies based on ultraviolet (UV) radiations emitted by Light-Emitting Diodes (LED), as a wastewater tertiary treatment, have been shown to be promising for water reuse. Here, we assessed the fate of two ubiquitous pollutants, carbamazepine and anthracene, in soil watered with either UV-LED treated wastewaters or irrigation water. After 3 months, anthracene and carbamazepine were transformed two and three times faster respectively, in soils watered with UV-LED wastewater than in soils watered with tap water (probably because of the addition of organic matter by the effluent). Laccase activity was induced in the presence of the pollutants and anthraquinone was found as anthracene product of oxidation by laccases. Moreover, the addition of these pollutants into soil did not affect the functional diversity of autochthonous microbial communities assessed by Ecolog plates. Cellulase, protease and urease activities increased in soils watered with UV-LED treated wastewaters (UV-LED WW), showing transformation of organic matter from the effluent and lipase activity increased by anthracene addition, confirming the potential role of these enzymes as indicators of hydrocarbon contamination.

International audience; Soil microbial activity Faecal indicator Catabolic activity Enzymatic activities a b s t r a c t Advanced oxidation processes based on UV radiations have been shown to be a promising wastewater disinfection technology. The UV-LED system involves innovative materials and could be an advantageous alternative to mercury-vapor lamps. The use of the UV-LED system results in good water quality meeting the legislative requirements relating to wastewater reuse for irrigation. The aim of this study was to investigate the impact of watering with UV-LED treated wastewaters (UV-LED WW) on soil parameters. Solid-state 13 C NMR shows that watering with UV-LED WW do not change the chemical composition of soil organic matter compared to soil watered with potable water. Regarding microbiological parameters, laccase, cellulase, protease and urease activities increase in soils watered with UV-LED WW which means that organic matter brought by the effluent is actively degraded by soil microorganisms. The functional diversity of soil microorganisms is not affected by watering with UV-LED WW when it is altered by 4 and 8 months of watering with wastewater (WW). After 12 months, functional diversity is similar regardless of the water used for watering. The persistence of faecal indicator bacteria (coliform and enterococci) was also determined and watering with UV-LED WW does not increase their number nor their diversity unlike soils irrigated with activated sludge wastewater. The study of watering-soil microcosms with UV-LED WW indicates that this system seems to be a promising alternative to the UV-lamp-treated wastewaters. ª

International audience; The electrochemical oxidation of an aqueous phenol solution was studied via a novel process. Experiments were conducted by recirculating a slurry electrode made of the product to be treated (phenol) and a catalyst (carbon black) through a flow-by electrolyser with a vertical stack of perforated Ti/Pt electrodes. Both the capacity of high adsorption of organic compounds and gases and the conductivity properties of Carbon Black allowed the acceleration of the degradation. High pressure liquid chromatography (HPLC) analysis was used to follow phenol loss and the formation of by-products. Gas chromatography (GC) analysis revealed the presence of two gases: oxygen-electrogenerated by the oxidation of water- and carbon dioxide produced by both phenol and CB oxidation. Other experiments under nitrogen and oxygen flow were performed in a closed reactor cell and proved that oxygen generated by Ti/Pt electrodes is sufficient to obtain the full degradation of phenol. The effects of CB concentration (ranging from 0 to 4 g l−1), of the nature of CB and of the applied current (from 0 to 20 A) were investigated. An increase of CB concentration and applied current was found to shift product distribution to favour the formation of carbon dioxide. A removal efficiency of 100% was obtained in a reaction time of 15 min under the following conditions: an initial phenol concentration of 1 mmol l−1, 4 g l−1 of CB, an applied current of 10 A, a flow rate of 10 ml s−1 and a temperature of 30°C.

International audience; Wastewater reuse for irrigation is an interesting alternative for many Mediterranean countries suffering from water shortages. The development of new technologies for water recycling is a priority for these countries. In this study we test the efficiency of UV-LEDs (Ultraviolet-Light-Emitting Diodes) emitting UV-A or UV-C radiations, used alone or coupled, on bacterial and chemical indicators. We monitored the survival of fecal bioindicators found in urban wastewaters and the oxidation of creatinine and phenol which represent either conventional organic matter or the aromatic part of pollution respectively. It appears that coupling UV-A/UV-C i) achieves microbial reduction in wastewater more efficiently than when a UV-LED is used alone, and ii) oxidizes up to 37% of creatinine and phenol, a result comparable to that commonly obtained with photoreactants such as TiO 2 .

International audience; Despite evidence of formation of brominated compounds in seawater swimming pools treated with chlorine, no data about exposure levels to these compounds have been reported. To address this issue, a survey has been carried out in four establishments (representing 8 pools) fed with seawater and devoted to relaxing and cure treatments (thalassotherapy centres located in Southeast of France). Carcinogenic and mutagenic brominated disinfection byproducts (trihalomethanes -THM- and halogenated acetic acids -HAA-) were quantified at varying levels, statistically related to organic loadings brought by bathers, and not from marine organic matter, and also linked to activities carried out in the pools (watergym vs swimming). Bromoform and dibromoacetic acid, the most abundant THM and HAA detected, were measured at levels up to 18-fold greater than the maximum contaminant levels of 60 and 80 mu g/L fixed by US.EPA in drinking waters. The correlations between these disinfection byproducts and other environmental factors such as nitrogen, pH, temperature, free residual chlorine, UV254, chloride and bromide concentrations, and daily frequentation were examined. Because thalassotherapy and seawater swimming pools (hotels, cruise ships, ...) are increasing in use around the world and because carcinogenic and mutagenic brominated byproducts may be produced in chlorinated seawater swimming pools, specific care should be taken to assure cleanliness of users (swimmers and patients taking the waters) and to increase water circulation through media filters to reduce levels of brominated byproducts. (C) 2011 Elsevier Ltd. All rights reserved.

International audience; This paper presents a simple, accurate and multi-sample method for the determination of volatile fatty acids (VFAs) thanks to a 96-well microplate technique. A procedure using an activating reagent of the carboxylic function (water-soluble carbodiimide EDC) and a fluorescent amino labeling reagent (N-(1-naphthyl)ethylenediamine, EDAN) allows the formation of an isoindole derivative that needs to be separated from initial fluorescent amine for efficient VFAs determination. Isolation of these fluorescent VFA-derivatives was carried out by use of the fluorescent quenching of EDAN with o-phthaldialdehyde (OPA). Quenching was most efficient at pH around 7 and by heating at 40 degrees C within the microplate reader. This optimized procedure has been applied to various carboxylic acids and other organic compounds, demonstrating that VFA exhibit the highest fluorescence responses with homogeneous results for the main ones (acetic, propionic and butyric acid, all mass concentration expressed as acetic acid equivalents). This protocol was calibrated against acetic acid and determination of VFA was thus possible in the range 3.9-2000 mg L-1 (acetic acid equivalents). Subsequent application to real samples (sewage sludges or anaerobically digested samples) and comparison to gas chromatography analyses gave accurate results, proving the great potential of our high-throughput microplate-based technique for the analysis of VFA. (C) 2011 Elsevier B.V. All rights reserved.

International audience; In the present work, a solid phase extraction (SPE) is hyphenated with an automatic MSFIA system to improve the selenite determination based on the reaction of selenite with aromatic o-diamines (such as 2,3-diaminonaphthalene (DAN)) to form the piazselenol complex. This reaction is greatly influenced by acid concentration, temperature, the time needed for colour development, and presence of foreign ions.For these reasons a thermostatic bath, glycine, and Na2-EDTA are used as heater, buffer, and masking agent, respectively. The principle of the determination is based on the sorption of the piazselenol onto a C18 membrane disk, followed by its elution by acetonitrile. The piazselenol can then be detected by absorptiometry or fluorometry, both detection techniques being tested in our system. The best detection limit (1.7 g L−1) and RSD (3.04%) are obtained by absorptiometry at 380 nm. Environmental samples were spiked and analyzed, with recoveries close to 100%.

International audience; Solid-phase extraction for cationic elements is a promising approach for water treatment or for analysis applications. However, supports that allow the selective extraction and/or preconcentration of metalloid species are still not widespread. A new chelating sorbent has been prepared by grafting 2,3-diaminonaphtalene (DAN) on Amberlite® XAD-4 resin beads via a diazo bridge. The synthesis was first carried out at a molecular level to optimise experimental conditions and to facilitate characterisation of solid sorbent by FTIR. TGA, Py-GC/MS experiments and back titration of amine functions showed that the sorbent was grafted. Se(IV) was retained by grafted Amberlite® XAD-4 with a rate of 88% at pH 2 and 80 °C. This paper presents a convenient way of grafting DAN on polystyrene-like resins and the first applications of these supports in solid-phase extraction of Se(IV).

Correspondance auteur: Boudenne J.L. E-mail: jean-luc.boudenne@univ-provence.fr; International audience; This paper presents a simple, rapid, and accurate method suitable for on-site measurement of short-chain volatile fatty acids (SCFA) in various environmental samples. This fluorimetric method involves a derivatization step of SCFA with N-(1-naphthyl)ethylenediamine (EDAN) and allows determination of acetic, butyric, propionic, valeric, lactic, succinic, and p-hydroxybenzoic acids in approximatively 10 min. To evaluate specificity and accuracy of the method, both laboratory-made waters and real samples ranging from wastewater plant and river to soils and composts have been tested. Good accuracy and correlation (r(2) = 0.9887) with HPIC determination have been obtained. The potential interference effect has been taken into account with compounds like humic substances, alcohols, amines, aldehydes, and metallic ions. Ibis method seems thus well designed for the determination of total SCFA in waters, in the range 0.84-500 mg/L. Because this method seems well suited for following of anaerobic treatment, it has been calibrated versus acetic acid-equivalent

Solid-phase extraction (SPE) of trace elements before their analysis has become a conventional pretreatment step of analytes because of their frequent low concentrations in numerous samples. Additionally, interfering compounds often accompagny analytes of interest, thus requiring a clean-up step. The preconcentration step and/or matrix removal can be efficiently improved by chemometric approaches allowing obtention of reliable results. Single variable approach is often used but is time and cost consuming, and may be the source of mistakes; multivariable approach allows to overcome these problems and increases the probability of global optimum finding. In order to obtain a set of experimental conditions for the selective extraction of Al(III) in water samples, onto a modified organic support (salicylic acid grafted on XAD-4), a multicriteria approach (response surface methodology) has been applied. The extraction method was optimized by the aid of a factorial design and a uniform shell Doehlert design for six variables: sample percolation flow rate, trace metal amount, sample volume, concentration and volume of HCl used for elution of aluminium. Results demonstrate the synergic effects of four factors and allow us to define working ranges for each parameter tested. The designed SPE procedure was then sucessfully applied to synthetic and real samples, issued from a potable water treatment unit.

In this work, Amberlite XAD-4 resin functionalized with salicylic acid was synthetized, characterized and applied as a new packing material for an on-line system to iron determination in aqueous samples. The detection method is based on the sorption of Fe(III) ions in a minicolumn containing the synthesized resin, followed by a desorption step using an acid solution and measurement of iron by vis-spectrophotometry (CAS method). The optimization of the solid-phase extraction system was performed using factorial design and Doehlert matrix considering six variables: sample percolation rate (0.5–9 ml min −1 ), sample metal concentration (20–200 μg l −1 ), flow-through sample volume (0–5 ml) (all three directly linked to the extraction step), elution flow-rate (0.5–9 ml min −1 ), concentration and volume of eluent (HCl 0.1–0.5 M) (all three directly linked to the elution step). The aim of this study was to obtain a set of operating ranges for the six variables tested in order to obtain – by means of a mathematical function allowing maximisation of each response (desirability function) – at least 90% of iron recovery rates. Using the experimental conditions defined in the optimization, the method allowed iron determination with achieved detection limit of 2.3 μg l −1 and precision (assessed as the relative standard deviation) of 9.3–2.8% for iron solutions of 10.0–150 μg l −1 . Real samples (coming from a water treatment unit) were used successfully when evaluating potentialities of the developed SPE procedure coupled to a spectrophotometric determination.