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In this study, arsenic resistant bacteria were isolated from sediments of an arsenic contaminated river. Arsenic tolerance of bacteria isolated was carried out by serial dilution on agar plate. Redox abilities were investigated using KMnO4. arsC and aox genes were detected by PCR and RT-PCR, respectively. Bacterial populations were identified by RapID system. Forty nine bacterial strains were isolated, of these, 55 % corresponded to the reducing bacteria, 4% to oxidizing bacteria, 8% presented both activities and in 33% of the bacteria none activity was detected. arsC gene was detected in 11 strains and aox genes were not detected. The activity of arsenic transforming microorganisms in river sediment has significant implications for the behavior of the metalloid.

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Abatement of the fluorinated antidepressant fluoxetine (Prozac) and its reaction by-products by electrochemical advanced methods, Applied Catalysis B, Environmental http://dx.GRAPHICAL ABSTRACT Fluoxetine hydrochloride (fluorinated antidepressant) 4 primary aromatics 1 chloroaromatic 4 carboxylic acids CO 2 F  NO 3  UVA light BDD(  OH)  OH Research Highlights Fluoxetine hydrochloride treated with Pt, RuO 2 -based or BDD anode and H 2 O 2 generation  Faster mineralization by PEF with a BDD anode due to BDD(  OH),  OH and UVA light  Pseudo-first-order decay by AO-H 2 O 2 , EF and, more rapidly, by PEF using a BDD anode  Degradation of fluoxetine with F  and NO 3  formation and partial Cl  oxidation to HClO  Detection of 4 primary aromatics, 1 chloroaromatic derivative and 4 carboxylic acids AbstractThe degradation of the fluorinated antidepressant fluoxetine, as hydrochloride, was comparatively studied in sulfate medium at pH 3.0 by anodic oxidation with electrogenerated H 2 O 2 (AO-H 2 O 2 ), electro-Fenton (EF) and photoelectro-Fenton (PEF). Experiments were performed with 100 mL solutions in an undivided tank reactor equipped with a Pt, RuO 2 -based or boron-doped diamond (BDD) anode and an air-diffusion cathode for continuous H 2 O 2 production. The BDD anode showed higher mineralization rate due to the great production of physisorbed BDD(  OH), which has larger reactivity to oxidize the drug and intermediates. The degradation rate was enhanced by EF with 0.50 mM Fe 2+ due to the additional production of  OH in the bulk from Fenton's reaction. The degradation was even faster using PEF owing to the additional photolytic action of UVA radiation.The most effective process was PEF with a BDD anode achieving 94% mineralization at 300 min.The fluoxetine decay followed a pseudo-first-order kinetics, being quicker in the order: AO-H 2 O 2 < EF < PEF. The effect of the current density and drug concentration on the mineralization rate and fluoxetine decay was clarified. Oxidation of fluoxetine by hydroxyl radicals yielded four aromatic by-products, as found by GC-MS. Additionally, a chloroaromatic compound was identified as a result of the reaction of active chlorine, which was formed in situ from the oxidation of chloride ion at the BDD anode. Four short-chain linear carboxylic acids, being oxalic and formic acid more abundant, were identified. In PEF, fluorine atoms of fluoxetine were completely released as fluoride ion, whereas the initial nitrogen was converted to nitrate ion in all cases. A reaction pathway for fluoxetine mineralization by the electrochemical advanced methods is finally proposed.