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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.

Highlights: • Overview on oxidative treatment processes for different industrial applications • Compilation of disinfection by-product types/concentrations in marine water uses • Estimation of global DBP inputs into marine water from different industries • Comparison of anthropogenic bromoform production to emissions from natural sources Abstract: Oxidative treatment of seawater in coastal and shipboard installations is applied to control biofouling and/or minimize the input of noxious or invasive species into the marine environment. This treatment allows a safe and efficient operation of industrial installations and helps to protect human health from infectious diseases and to maintain the biodiversity in the marine environment. On the downside, the application of chemical oxidants generates undesired organic compounds, so-called disinfection by-products (DBPs), which are discharged into the marine environment. This article provides an overview on sources and quantities of DBP inputs, which could serve as basis for hazard analysis for the marine environment, human health and the atmosphere. During oxidation of marine water, mainly brominated DBPs are generated with bromoform (CHBr3) being the major DBP. CHBr3 has been used as an indicator to compare inputs from different sources. Total global annual volumes of treated seawater inputs resulting from cooling processes of coastal power stations, from desalination plants and from ballast water treatment in ships are estimated to be 470 – 800 × 109 m3, 46 × 109 m3 and 3.5 × 109 m3, respectively. Overall, the total estimated anthropogenic bromoform production and discharge adds up to 13.5 – 21.8 × 106 kg/a (kg per year) with contributions of 11.8 – 20.1 × 106 kg/a from cooling water treatment, 0.89 × 106 kg/a from desalination and 0.86 × 106 kg/a from ballast water treatment. This equals approximately 2 – 6 % of the natural bromoform emissions from marine water, which is estimated to be 385 – 870 × 106 kg/a.

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; 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; 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; 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; 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.

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.

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.

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; 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; 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.