Glycated bovine serum albumin for use in feeding trials with animal models - In vitro methodology and characterization of a glycated substrate for modifying feed pellets.

This study investigated different methods to produce N-carboxymethyl-lysine (CML)-enriched bovine serum albumin (BSA) as alternatives to the classical approach using glyoxylic acid (GA) and sodium cyanoborohydride (NaBHCN) which results in toxic hydrogen cyanide (HCN). The reaction of GA (6 mmol/L) and NaBHCN (21 mmol/L) to produce CML remained the most effective with CML yields of 24-35%, followed by 13-24% using 300 mmol/L glyoxal (GO). GA promoted specific modification of lysine to CML, and fewer structural modifications of the BSA molecule compared with GO, as evidenced by fluorescence and proteomic analyses.

Iodide sources in the aquatic environment and its fate during oxidative water treatment - A critical review.

Iodine is a naturally-occurring halogen in natural waters generally present in concentrations between 0.5 and 100 µg L. During oxidative drinking water treatment, iodine-containing disinfection by-products (I-DBPs) can be formed.

Dynamics of chlorinated aliphatic hydrocarbons in the Chalk aquifer of northern France.

The Chalk aquifer used for drinking-water production in the southwest of the Lille European Metropolis is threatened by the presence of chlorinated aliphatic hydrocarbons (CHCs), their concentrations in groundwater regularly exceeding the regulatory limits for drinking water in France. This hinders its use for drinking-water production. Understanding the dynamics and spatial distribution of CHC in the aquifer is a key factor for resource sustainability.

Formation and removal of disinfection by-products in a full scale drinking water treatment plant.

In this case study, high sensitivity simple methods for the analysis of trihalomethanes (THM4), iodinated-trihalomethanes (I-THMs), haloacetic acids (HAAs), bromide, iodide and iodate have been developed. A one-step procedure for the analysis of haloacetic acids by head-space GC-MS provides good reproducibility and low limits of quantification (≤50 ng L). These methods were applied to characterize the formation of disinfection by-products (DBPs) in a full scale drinking water treatment plant.

Natural organic matter-cations complexation and its impact on water treatment: A critical review.

The quality and quantity of natural organic matter (NOM) has been observed to evolve which poses challenges to water treatment facilities. Even though NOM may not be toxic itself, its presence in water has aesthetic effects, enhances biological growth in distribution networks, binds with pollutants and controls the bioavailability of trace metals. Even though NOM has heterogeneous functional groups, the predominant ones are the carboxyl and the phenolic groups, which have high affinities for metals depending on the pH.

Assessment of the treatment efficiency of an urban stormwater pond and its impact on the natural downstream watercourse.

During the last few decades, stormwater ponds have become an alternative management practice in order to avoid flooding and to contain rainwater and runoff in urban areas where impervious land cover has increased. A second purpose of stormwater ponds is to improve the quality of runoff water that is usually contaminated with nitrogen, phosphorus, metals and organic micropollutants. Processes used are based on natural methods such as settlement and contribute to minimize the impact of these inputs to the natural aquatic system.

Comparison of POCIS passive samplers vs. composite water sampling: A case study.

The relevance of Polar Organic Chemical Integrative Samplers (POCIS) was evaluated for the assessment of concentrations of 46 pesticides and 19 pharmaceuticals in a small, peri-urban river with multi-origin inputs. Throughout the period of POCIS deployment, 24h-average water samples were collected automatically, and showed the rapid temporal evolution of concentrations of several micropollutants, as well as permitting the calculation of average concentrations in the water phase for comparison with those estimated from POCIS passive samplers. In the daily water samples, cyproconazol, epoxyconazol and imidacloprid showed high temporal variations with concentrations ranging from under the limit of detection up to several hundreds of ngL.

Assessing the transport of PAH in the surficial sediment layer by passive sampler approach.

A new method based on passive samplers has been developed to assess the diffusive flux of fluorene, fluoranthene and pyrene in the sediment bed and across the sediment-water interface. The dissolved compound concentration gradient in the sediment in the vertical direction was measured at the outlet of a storm water pond by using polyethylene strips as passive samplers. Simultaneously, the dissipation of a set of tracer compounds preloaded in the passive samplers was measured to estimate the effective diffusion coefficients of the pollutants in the sediment.

A new application of passive samplers as indicators of in-situ biodegradation processes.

In this paper, a method for evaluating the in-situ degradation of nitro polycyclic aromatic hydrocarbons (nitro-PAH) in sediments is presented. The methodology is adapted from the passive sampler technique, which commonly uses the dissipation rate of labeled compounds loaded in passive sampler devices to sense the environmental conditions of exposure. In the present study, polymeric passive samplers (made of polyethylene strips) loaded with a set of labeled polycyclic aromatic hydrocarbons (PAH) and nitro-PAH were immersed in sediments (in field and laboratory conditions) to track the degradation processes.

Active biomonitoring for assessing effects of metal polluted sediment resuspension on gammarid amphipods during fluvial traffic.

The resuspension of polluted sediments by boat traffic could release substantial amounts of metals to the water column, affecting at the same time their bioavailability. In order to characterize the impact of sediment resuspensions on biota, caged amphipods have been deployed on three different channelized watercourses in Northern France. Firstly, the biological responses of transplanted freshwater gammarid amphipods, Gammarus fossarum, described by trace metal accumulation, feeding and reproduction activities were quite similar for the three water courses despite the differences of metal contamination and navigability.

Photodecomposition of iodinated contrast media and subsequent formation of toxic iodinated moieties during final disinfection with chlorinated oxidants.

Large amount of iodinated contrast media (ICM) are found in natural waters (up to μg.L(-)(1) levels) due to their worldwide use in medical imaging and their poor removal by conventional wastewater treatment. Synthetic water samples containing different ICM and natural organic matter (NOM) extracts were subjected to UV254 irradiation followed by the addition of chlorine (HOCl) or chloramine (NH2Cl) to simulate final disinfection.

Water quality assessment of a small peri-urban river using low and high frequency monitoring.

The biogeochemical behaviors of small rivers that pass through suburban areas are difficult to understand because of the multi-origin inputs that can modify their behavior. In this context, a monitoring strategy has been designed for the Marque River, located in Lille Metropolitan area of northern France, that includes both low-frequency monitoring over a one-year period (monthly sampling) and high frequency monitoring (measurements every 10 minutes) in spring and summer. Several environmental and chemical parameters are evaluated including rainfall events, river flow, temperature, dissolved oxygen, turbidity, conductivity, nutritive salts and dissolved organic matter.

On the bioavailability of trace metals in surface sediments: a combined geochemical and biological approach.

The bioavailability of metals was estimated in three river sediments (Sensée, Scarpe, and Deûle Rivers) impacted by different levels of Cu, Cd, Pb, and Zn (Northern France). For that, a combination of geochemistry and biological responses (bacteria and chironomids) was used. The results obtained illustrate the complexity of the notion of "bioavailability.

Reaction of bromine and chlorine with phenolic compounds and natural organic matter extracts--Electrophilic aromatic substitution and oxidation.

Phenolic compounds are known structural moieties of natural organic matter (NOM), and their reactivity is a key parameter for understanding the reactivity of NOM and the disinfection by-product formation during oxidative water treatment. In this study, species-specific and/or apparent second order rate constants and mechanisms for the reactions of bromine and chlorine have been determined for various phenolic compounds (phenol, resorcinol, catechol, hydroquinone, phloroglucinol, bisphenol A, p-hydroxybenzoic acid, gallic acid, hesperetin and tannic acid) and flavone. The reactivity of bromine with phenolic compounds is very high, with apparent second order rate constants at pH 7 in the range of 10(4) to 10(7) M(-1) s(-1).

Oxidative treatment of bromide-containing waters: formation of bromine and its reactions with inorganic and organic compounds--a critical review.

Bromide (Br(-)) is present in all water sources at concentrations ranging from ≈ 10 to >1000 μg L(-1) in fresh waters and about 67 mg L(-1) in seawater. During oxidative water treatment bromide is oxidized to hypobromous acid/hypobromite (HOBr/OBr(-)) and other bromine species. A systematic and critical literature review has been conducted on the reactivity of HOBr/OBr(-) and other bromine species with inorganic and organic compounds, including micropollutants.

Iodate and iodo-trihalomethane formation during chlorination of iodide-containing waters: role of bromide.

The kinetics of iodate formation is a critical factor in mitigation of the formation of potentially toxic and off flavor causing iodoorganic compounds during chlorination. This study demonstrates that the formation of bromine through the oxidation of bromide by chlorine significantly enhances the oxidation of iodide to iodate in a bromide-catalyzed process. The pH-dependent kinetics revealed species specific rate constants of k(HOBr + IO(-)) = 1.

Enhancement of carboxylic acid degradation with sulfate radical generated by persulfate activation.

The aim of this work was to investigate the generation of sulfate radical for the removal of two carboxylic acids in aqueous solution: acetic and citric acids. From photochemical and radiolytic processes, kinetics of the degradation of these two carboxylic acids was studied as a function of the pH of the solution. It was shown that the maximum of acetic acid degradation occurred at pH 5.

Degradation of acetic acid with sulfate radical generated by persulfate ions photolysis.

The photolysis of S(2)O(8)(2-) was studied for the removal of acetic acid in aqueous solution and compared with the H(2)O(2)/UV system. The SO(4)(-) radicals generated from the UV irradiation of S(2)O(8)(2-) ions yield a greater mineralization of acetic acid than the ()OH radicals. Acetic acid is oxidized by SO(4)(-) radicals without significant formation of intermediate by-products.