4-Methylumbeliferone Treatment at a Dose of 1.2 g/kg/Day Is Safe for Long-Term Usage in Rats.

4-methylumbelliferone (4MU) has been suggested as a potential therapeutic agent for a wide range of neurological diseases. The current study aimed to evaluate the physiological changes and potential side effects after 10 weeks of 4MU treatment at a dose of 1.2 g/kg/day in healthy rats, and after 2 months of a wash-out period. Our findings revealed downregulation of hyaluronan (HA) and chondroitin sulphate proteoglycans throughout the body, significantly increased bile acids in blood samples in weeks 4 and 7 of the 4MU treatment, as well as increased blood sugars and proteins a few weeks after 4MU administration, and significantly increased interleukins IL10, IL12p70 and IFN gamma after 10 weeks of 4MU treatment. These effects, however, were reversed and no significant difference was observed between control treated and 4MU-treated animals after a 9-week wash-out period.

Molecular mechanisms and potential applications of chondroitin sulphate in managing post-traumatic osteoarthritis.

Post-traumatic osteoarthritis (PTOA), a disorder of the synovium, subchondral bone, and cartilage that affects the entire joint, constitutes approximately 12% of all cases of symptomatic osteoarthritis. This review summarizes the pathogenetic mechanisms that underlie the positive influence of chondroitin sulphates (CSs) on PTOA as means of preventive and therapeutic treatment. Mechanisms of PTOA development involve chondrocytes undergoing various forms of cell death (apoptosis, pyroptosis, necroptosis, ferroptosis and/or necrosis). Chondroitin sulphates are a class of glycosaminoglycans that improve the structure and function of cartilage and subchondral bone, which is associated with their ability to decrease the activation of NF-κB and p38 MAPK, and up-regulate Nrf2. Standardized small fish extract (SSFE) is an example of the drugs that can attenuate NF-κB-mediated systemic inflammation, potentially helping to reduce joint inflammation and cartilage degradation, improve joint function, and alleviate pain and disability in patients with these conditions.

Investigation of water treatment sludge from drinking water treated with Zetafloc 553I coagulant for phosphorus removal from wastewater.

Water treatment sludge have shown promising results as adsorbent for phosphorus and sulphate removal from real wastewater. The study was conducted through batch kinetics and equilibrium isotherm modes. The chemical composition reveal that aluminium compounds were dominant in the fresh sludge and aluminium phosphates were also observed in the used sludge. The results reveal that Manganese was leached from the material at all pH values investigated with the highest level observed at pH 2 and all concentrations higher than the national standard of discharge into the relevant environment. The point of zero charge of the adsorbent was pH 8.04 and high adsorption capacities for both sulphate and phosphate ions were observed at pH values lower than this point. Batch kinetic results revealed 96.0 ± 3.0% sulphates removal in the first 30 min whereas the highest phosphates removal was 88.0 ± 4.0% attained at 300 min of the experiment. Pseudo - second order reaction fitted the data better than Pseudo-first order reaction. The percentage removal of sulphates was observed decreasing with increasing adsorbent dose after 2.4 g dose but removal increased with increasing media dosage for phosphorus. The equilibrium data was better described by Freundlich isotherm with constants relating to adsorption capacities being 6.76 and 6.2 L g-1 respectively, for sulphates and phosphates adsorption. The adsorption capacity of phosphates was observed decreasing with increasing temperature, but the results were not conclusive in the case of sulphates. The results reveal that copper, nickel, and zinc have affinity for sulphates. The water treatment sludge can be used for phosphate and sulphate removal from wastewater though the leachability of manganese is a concern. Further investigations through fixed bed columns will need to be investigated before field trials. In conclusion, the sludge can be used as adsorbent for phosphorus and sulphates removal from wastewater through filtration and onsite treatment methods such as vertical or horizontal flow wetland systems. The success of the adsorbent will reduce the costs associated with its disposal which can also lead to leachability of metals into the environment with time.

Resistance to Chemical Attack of Hybrid Fly Ash-Based Alkali-Activated Concretes.

The environmental impacts related to Portland cement production in terms of energy consumption, the massive use of natural resources and CO2 emissions have led to the search for alternative cementitious materials. Among these materials, alkali-activated cements based on fly ash (FA) have been considered for concrete production with greater sustainability. In the present article, the chemical durability properties (resistance to sulphates, chloride permeability, and resistance to carbonation) of a hybrid alkali-activated concrete based on fly ash-ordinary Portland cement (FA/OPC) with proportions of 80%/20% were evaluated. It is noted that the FA was a low-quality pozzolan with a high unburned carbon content (20.67%). The results indicated that FA/OPC concrete had good durability with respect to the OPC concrete, with 95% less expansion in the presence of sodium sulphate and a 2% strength loss at 1100 days, compared with the 56% strength loss of the OPC concrete. In addition, FA/OPC showed lower chloride permeability. On the contrary, the FA/OPC was more susceptible to carbonation. However, the residual compressive strength was 23 MPa at 360 days of CO2 exposure. Based on the results, FA/OPC, using this type of FA, can be used as a replacement for OPC in the presence of these aggressive agents in the service environment.

HS3ST2 expression is critical for the abnormal phosphorylation of tau in Alzheimer's disease-related tau pathology.

Heparan sulphate (glucosamine) 3-O-sulphotransferase 2 (HS3ST2, also known as 3OST2) is an enzyme predominantly expressed in neurons wherein it generates rare 3-O-sulphated domains of unknown functions in heparan sulphates. In Alzheimer's disease, heparan sulphates accumulate at the intracellular level in disease neurons where they co-localize with the neurofibrillary pathology, while they persist at the neuronal cell membrane in normal brain. However, it is unknown whether HS3ST2 and its 3-O-sulphated heparan sulphate products are involved in the mechanisms leading to the abnormal phosphorylation of tau in Alzheimer's disease and related tauopathies. Here, we first measured the transcript levels of all human heparan sulphate sulphotransferases in hippocampus of Alzheimer's disease (n = 8; 76.8 ± 3.5 years old) and found increased expression of HS3ST2 (P < 0.001) compared with control brain (n = 8; 67.8 ± 2.9 years old). Then, to investigate whether the membrane-associated 3-O-sulphated heparan sulphates translocate to the intracellular level under pathological conditions, we used two cell models of tauopathy in neuro-differentiated SH-SY5Y cells: a tau mutation-dependent model in cells expressing human tau carrying the P301L mutation hTau(P301L), and a tau mutation-independent model in where tau hyperphosphorylation is induced by oxidative stress. Confocal microscopy, fluorescence resonance energy transfer, and western blot analyses showed that 3-O-sulphated heparan sulphates can be internalized into cells where they interact with tau, promoting its abnormal phosphorylation, but not that of p38 or NF-κB p65. We showed, in vitro, that the 3-O-sulphated heparan sulphates bind to tau, but not to GSK3B, protein kinase A or protein phosphatase 2, inducing its abnormal phosphorylation. Finally, we demonstrated in a zebrafish model of tauopathy expressing the hTau(P301L), that inhibiting hs3st2 (also known as 3ost2) expression results in a strong inhibition of the abnormally phosphorylated tau epitopes in brain and in spinal cord, leading to a complete recovery of motor neuronal axons length (n = 25; P < 0.005) and of the animal motor response to touching stimuli (n = 150; P < 0.005). Our findings indicate that HS3ST2 centrally participates to the molecular mechanisms leading the abnormal phosphorylation of tau. By interacting with tau at the intracellular level, the 3-O-sulphated heparan sulphates produced by HS3ST2 might act as molecular chaperones allowing the abnormal phosphorylation of tau. We propose HS3ST2 as a novel therapeutic target for Alzheimer's disease.

Positive correlations between hCAP18/LL-37 and chondroitin sulphate levels in chronic periodontitis.

AIM: To measure the levels of hCAP18/LL-37 in gingival crevicular fluid from patients with periodontal diseases compared with healthy controls and to determine the correlation between hCAP18/LL-37 and chondroitin sulphate (CS) levels in patients with periodontitis. MATERIAL AND METHODS: Gingival crevicular fluid samples from 51 patients and 25 healthy volunteers were analysed for the hCAP18/LL-37 levels by immunoblotting and were determined for the CS levels by the competitive enzyme-linked immunosorbent assay. RESULTS: Tris buffer pH 9.85 was selected to recover hCAP18/LL-37 from Periopaper strips, in which the percentages of recovery were around 70%. The median levels of hCAP18/LL-37 in the aggressive and the chronic periodontitis (CP) groups were significantly greater than those in the gingivitis and the healthy groups (p < 0.05). Significant correlations between the unprocessed 18-kDa fragment and CS levels (r = 0.650; p < 0.001) and between the mature 4.6-kDa fragment and CS levels (r = 0.502; p < 0.001) were observed only in the CP group. CONCLUSION: The significant correlations between the hCAP18/LL-37 and the CS levels were found in CP, but not in aggressive periodontitis. The presence versus absence of such correlations may be clinically applicable to help clinicians distinguish between two distinct types of periodontitis.

Detection time comparison of non-hydrolysed sulphated metabolites of metenolone, mesterolone and 17α-methyltestosterone analysed by four different mass spectrometric techniques.

The frequent detection of anabolic androgenic steroids (AAS) indicates their popularity among rule-breaking athletes. The so called long-term metabolites play a crucial role in their detection, and non-hydrolysed sulphated metabolites have gained renewed interest, as research has demonstrated their extended detection time compared to the more conventional markers (e.g., for metenolone and mesterolone). Their potential has been investigated using liquid and gas chromatography-mass spectrometry (LC- and GC-MS). However, due to their complementary nature, chances are that the most promising metabolite on one technique does not necessarily exhibit the same behaviour on the other and vice versa. Therefore, a comparison was carried out where as a trial model, metenolone, mesterolone and 17α-methyltestosterone were selected and the most likely long-term sulphated metabolites identified on four mass spectrometric instruments. Additionally, using a modified sample preparation procedure, comparison between conventional and non-hydrolysed sulphated metabolites between different GC-MS instruments was also included. When focusing on each individual marker, no cases were observed where a single metabolite provided a superior detection time on all instruments. Furthermore, for each AAS, there were incidences where a metabolite provided the best detection time on one instrument but could only be detected for a shorter period or not at all on other instruments. This demonstrates that metabolite detection windows and hence their added-value as target substance are unique and dependent on the analytical technique and not only on their pharmacokinetic behaviour. Consequently, in each case, a metabolite versus instrument evaluation is needed to maximise the probabilities of detecting doping offences.

Investigation of water treatment sludge for the treatment of saline water: Batch studies.

In this study, water treatment sludge was investigated through batch modes for the treatment of saline water to meet livestock drinking consents. The water quality was assessed using water quality index (WQI).The kinetic data was best described by the Pseudo - Second - Order model and the equilibrium isotherm by the Freundlich model. The maximum removal efficiency was 51.5 ± 0.65%, 22.6 ± 0.5% and 100% for Sulphates (SO4 2-), Chloride (Cl-), and Nitrates (NO3 -), respectively. The maximum removal efficiency of sodium (Na) and nickel (Ni) was 100% each at 0.4g dose and that of manganese (Mn) was 87.5% at 1.2g dose. The effect of temperature revealed that the adsorption capacity for anions, decreased with increasing temperature, whereas for the cations the adsorption capacities increased with increasing temperature. The water treatment sludge reduced the total dissolved solids (TDS) and electrical conductivity (EC) from the initial values of 19600 mgL-1 and 38900 µScm-1 to 98 mgL-1 and 1728 µScm-1,respectively. The Water Quality Indices were 37.35 and 7.57, before and after treatment, respectively. Water treatment sludge can be used for the pre-treatment process before using conventional treatment technologies. Pilot scale investigations should be conducted before field trials.

Dual-stage biorefinery to convert spentwash hydrolysate into oleochemicals using Trichosporon cutaneum and Yarrowia lipolytica.

Yeast lipids from low-cost renewable feedstock are valuable resources for oleochemicals thus enabling circular chemistry. Current study focuses on lipid and volatile fatty acid (VFA) production through dual-stage fermentation of spentwash in a biorefinery framework with Trichosporon cutaneum (Tc) and Yarrowia lipolytica (Yl). During cell proliferation phase, Tc and Yl accumulated 2.9 and 2.5 g/L of dry biomass respectively in acid-hydrolysed spentwash (AHSW) and produced 16 and 5.5 g/L of total VFA respectively. Lipid yields (29.8%) and lipid titres (0.89 g/L) were higher in Tc/AHSW, when compared to Yl indicating the efficacy of Tc in spentwash bioremediation. Lipid accumulation was enhanced to 35% in Tc/AHSW, in presence of 0.05% NH4Cl due to oxidative stress of ammonium ions. Analysis of fatty acid composition revealed the presence of higher oleic acid, which is ideal for biodiesel production. The results demonstrate a sustainable biorefinery model for bioremediation of spentwash and its value addition.

Quantification of Chlorides and Sulphates on Concrete Surfaces Using Portable X-ray Fluorescence. Optimization of the Measurement Method Using Monte Carlo Simulation.

A correct assessment of the pathologies that can affect a reinforced concrete structure is required in order to define the repair procedure. This work addresses the challenge of quantifying chlorides and sulphates directly on the surface of concrete. The quantification was carried out by means of X-ray fluorescence analysis on the surface of concrete specimens at different points with portable equipment. Concrete prisms were made with different amounts of NaCl and Na2SO4. To avoid the influence of coarse aggregate, a qualitative estimate of the amount of coarse aggregate analyzed has been made, although the results show that there is no significant influence. Monte Carlo simulations were carried out in order to establish the necessary number of random analyses of the mean value to be within an acceptable range of error. In the case of quantifying sulphates, it is necessary to carry out six random analyses on the surface, and eight measurements in the case of quantifying chlorides; in this way, it is ensured that errors are below 10% in 95% of the cases. The results of the study highlight that a portable XRF device can be used in situ to obtain concentrations of chlorides and sulphates of a concrete surface with good accuracy. There is no need to take samples and bring them to a laboratory, allowing lower overall costs in inspection and reparation works.

Phosphate and sulphate-mediated structure and stability of bone morphogenetic protein - 2 (BMP - 2): A spectroscopy enabled investigation.

Impact of different monovalent and divalent cationic salts of sulphates and phosphates on conformation and stability of BMP - 2 was unraveled by absorbance, fluorescence and circular dichroism (CD) spectroscopy. Increase in absorbance of protein confirms the ground-state complexation between salt and BMP - 2. Phosphate salts, with the exception of sodium phosphate quenched the fluorescence intensity. The nature of quenching was static, as revealed by temperature-dependent fluorescence studies (Stern-Volmer constant (KSV) decreased with rise in temperature). Moreover, kq (bimolecular quenching constant) was in the range of 1012 M-1 s-1, confirming binding of phosphate salts with the protein. Contrary to this, sulphate salts increased the fluorescence intensity and excited-state lifetime of BMP - 2 (2.668 ns), with the maximum calculated for 300 mM sodium sulphate (3.216 ns). Phosphates reduced the lifetime of protein, with the least observed in presence of 300 mM magnesium phosphate (1.480 ns). Thermal stability of the protein (Tm = 70.66 °C) was altered significantly upon interaction with phosphate salts; however, it did not vary significantly in case of sulphates (exception - magnesium sulphate). Experimental evidences confirm the role played by anionic group on protein conformation and stability and identifies monovalent and divalent cations as insignificant contributor.

Removal of Microcystin-LR from spiked natural and synthetic waters by anion exchange.

Cyanobacterial blooms are becoming a serious challenge across the globe due to changing climate and rainfall patterns as a consequence of human activities. In the present study, the fundamental interactions involved during the removal of Microcystin-LR (MCLR), one of the most commonly occurring cyanobacterial toxins, were investigated by employing strongly basic anion exchange (IX) resins. Several factors including the stoichiometric coefficients, competitive fractions and solute affinities were determined under various concentrations of inorganic ions and natural organic matter. The results indicated that suphates were the most competitive fractions with high affinity (α (affinity coefficient) values ~ 9) followed by nitrates (α ~ 4.7) and NOM fractions (α ~ 4.5, p < 0.05). The Equivalent Background Concentration Mode (EBC), that arises from the Ideal Adsorption Solution Theory (IAST), indicated a competitive fraction of ~2 µeq/L NOM, which approximates to <10% of the initial NOM concentrations, indicating a small fraction of the NOM resulting in the competitive effect. Further, studies with natural surface waters indicated that the MCLR uptake could be modeled using the IAST-EBC model and the IX resin could simultaneously removal of >90% of NOM, inorganic ions and MCLR at resin dosages of 3.6 meq/L or higher.

Rapid analytical method for the determination of organic and inorganic species in tomato samples through HPLC-ICP-AES coupling.

A HPLC-inductively coupled plasma atomic emission spectrometer (ICP-AES) hyphenation technique was used to determine the concentration of some organic (i.e., carbohydrates, carboxylic acids) as well as inorganic (metals and anions) compounds in tomato samples. A high efficiency nebulizer (HEN) coupled to a low inner volume cyclonic spray chamber (Cinnabar) was used to interface both techniques. The HPLC-ICP-AES chromatograms for organic compounds were obtained by plotting the 193.03nm carbon emission intensity versus time. In the present work, it was also possible to obtain information about the concentration of several metals in foodstuffs. Finally, by registering the intensity at the sulphur and phosphorous emission wavelengths, the content of anions such as sulphate and phosphate was determined. In general terms, the results obtained with HPLC-ICP-AES did not differ significantly from those found with a refractive index detector. Due to the huge amount of information provided by this hyphenation, it was possible to apply it to the discrimination among different samples of native tomato cultivars.

Endothelial cell surface limits coagulation without modulating the antithrombin potency.

Antithrombin (AT) binds in vitro and in vivo to endothelial cells through various receptors, including heparan sulphate glycosaminoglycan (HSPG) that could modulate the AT activity. A thrombin generation assay (TGA) was set up at the surface of HUVEC and HMVEC evaluating their participation in the coagulation-anticoagulation processes. TGA induced by 0.5 pM Tissue Factor was performed in normal or AT-deficient plasma spiked with various amounts of recombinant or plasma-derived AT (0, 0.1, 0.5 and 1.0 U/ml). To evaluate the role of HSPG or cellular anticoagulant receptors, cells were treated or not with heparin, a mix of heparanase I, II and III, a neutralizing anti-Endothelial Protein C Receptor (EPCR) or with an anti-Tissue Factor Pathway Inhibitor (TFPI) antibody. The presence of the cells diminished the TG in normal plasma and maintained anticoagulation in AT-deficient plasma. Spiking the AT-deficient plasma with different doses of AT demonstrated that the cells did not amplify the anticoagulant activity of AT. The recombinant AT binds the cells with a higher avidity than the plasma-derived one but this did not affect its anticoagulant potency. Moreover both bindings are independent of the HSPG. The antithrombotic activity kept in absence of AT was not inhibited by blocking antibodies directed against EPCR or TFPI. Our data did not reveal a major co-factor activity for AT from endothelial cells that could have been mediated by HSPG. In contrast, it reveals the presence of alternative anti-coagulant system(s) in two venous cell types that maintain an antithrombotic activity.

Re-evaluation of aluminium sulphates (E 520-523) and sodium aluminium phosphate (E 541) as food additives.

The Panel on Food Additives and Nutrient Sources added to Food (ANS) provided a scientific opinion re-evaluating the safety of aluminium sulphates (E 520-523) and sodium aluminium phosphate, acidic (E 541) as food additives. The Panel considered that adequate exposure and toxicity data were available. Aluminium sulphates (E 520-523) and sodium aluminium phosphate, acidic (E 541) are permitted as food additives in only a few specific products and the exposure is probably near zero. Aluminium compounds have low bioavailability and low acute toxicity. There is no concern with respect to genotoxicity and carcinogenicity. The no observed adverse effect level (NOAEL) for aluminium compounds in subchronic studies was 52 mg Al/kg body weight (bw) per day in rats and 90 mg Al/kg bw per day in dogs and the lowest NOAEL for neurotoxicity in rats was 30 mg Al/kg bw per day and for developing nervous system was 10-42 mg Al/kg bw per day in studies in mice and rats. The Panel concluded that aluminium sulphates (E 520-523) and sodium aluminium phosphate, acidic (E 541) are of no safety concern in the current authorised uses and use levels.

Theory and practice of corrosion related to ashes and deposits in a WtE boiler.

Corrosion of heat-exchanging components is one of the main operational problems in Waste-to-Energy plants, limiting the electrical efficiency that can be reached. Corrosion is mainly related to the devolatilization and/or formation of chlorides, sulphates and mixtures thereof on the heat-exchanging surfaces. Theoretical considerations on this corrosion were already put forward in literature, but this paper now for the first time combines theory with a large scale sampling campaign of several Waste-to-Energy plants. Based on the outcome of elemental and mineralogical analysis, the distribution of Cl and S in ashes sampled throughout the plant during normal operation is explained. Cl concentrations are high (15-20%) in the first empty pass, decrease in the second and third empty pass, but increase again in the convective part, whereas the S concentrations show an inverse behavior, with the highest concentrations (30%) observed in the second and third empty pass. Sampling of deposits on specific places where corrosion possibly occurred, gives a better insight in the mechanisms related to corrosion phenomena in real-scale WtE plants and provides practical evidence for some phenomena that were only assumed on the basis of theory or lab scale experiments before. More specific, it confirms the role of oxygen content, temperatures in the different stages of the boiler, the presence of polysulphates, Pb and Zb, and the concentrations of HCl and SO2 in the flue gas for different types of boiler corrosion.

Process performance determination data in thiocyanate biodegradation systems: Use of sulphate production.

This data article presents the utilization of sulphates as an indirect technique for the assessment of microbial growth, activity and SCN- biodegradation efficiency since the TDO were observed to be unable to utilise the produced sulphates as a source of sulphur (Mekuto e al., 2017) [1] The TDO demonstrated complete SCN- biodegradation while also utilizing the produced ammonium. The production of SO42- from SCN- biodegradation had a good correlation in comparison to the traditional methods of assessing microbial growth and activity i.e. direct cell counts (DCC), heterotrophic counts (CFU) and fluorescein production from fluorescein diacetate (FDA). The concentration of the produced SO42- demonstrated a similar logarithmic trend with the FDA, DCC and CFU techniques, thus confirming that the production of SO42- from SCN- biodegradation systems can be utilised as an indirect technique for the assessment of microbial growth, activity and SCN- biodegradation performance.

Determination of the four major surfactant classes in cleaning products by reversed-phase liquid chromatography using serially connected UV and evaporative light-scattering detection.

A method for the simultaneous determination of the most frequently used surfactant families -linear alkyl benzenesulphonates (LAS), alkyl ether sulphates (AES), fatty alcohol ethoxylates (FAE) and oleins (soaps, fatty acid salts) - in cleaning products, has been developed. The common reversed phase octyl (C8), pentafluorophenyl and biphenyl columns were not capable of separating the anionic LAS and AES classes; however, since only LAS absorbs in the UV, these two classes were independently quantified using a C8 column and serially connected UV and ELSD detection. The best compromise to resolve the four surfactant classes and the oligomers within the classes was achieved with a C8 column and an ACN/water gradient. To enhance retention of the anionic surfactants, ammonium acetate, as an ion-pairing agent compatible with ELSD detection, was used. Also, to shift the olein peaks with respect to that of the FAE oligomers, acetic acid was used. In the optimized method, modulation of the mobile phase, using ammonium acetate during elution of LAS and AES, and acetic acid after elution of LAS and AES, was provided. Quantitation of the overlapped LAS and AES classes was achieved by using the UV detector to quantitate LAS and the ELSD to determine AES by difference. Accuracy in the determination of AES was achieved by using a quadratic model, and by correcting the predicted AES concentration according to the LAS concentration previously established using the UV chromatogram. Another approach also leading to accurate predictions of the AES concentration was to increase the AES concentrations in the samples by adding a standard solution. In the samples reinforced with AES, correction of the predicted AES concentration was not required. FAE and olein were quantified using also quadratic calibration.

Application of stable isotopes (δ³4S-SO4, δ¹8O-SO4, δ¹5N-NO 3, δ¹8O-NO 3) to determine natural background and contamination sources in the Guadalhorce River Basin (southern Spain).

The integrated use of isotopes (δ(34)S-SO4, δ(18)O-SO4, δ(15)N-NO3, δ(18)O-NO3), taking into account existing hydrogeological knowledge of the study area (mainly hydrochemical), was applied in the Guadalhorce River Basin (southern Spain) to characterise SO4(2-) and NO3(-) sources, and to quantify natural background levels (NBLs) in groundwater bodies. According to Water Framework Directive 2000/60/EC and, more recently, Groundwater Directive 2006/118/EC, it is important to determine NBLs, as their correct assessment is the first, essential step to characterising groundwater bodies, establishing threshold values, assessing chemical status and identifying trends in pollutant concentrations. In many cases, NBLs are high for some parameters and types of groundwater, making it difficult to distinguish clearly between factors of natural or human origin. The main advantages of using stable isotopes in a complex area like the Guadalhorce River Basin that exhibits widely varying hydrogeological and hydrochemical conditions and longstanding anthropogenic influences (mainly agriculture, but also many others) is accurate determination of pollution sources and precise quantification of NBLs. Since chemical analyses only provides the concentration of pollutants in water and not the source, three isotopic sampling campaigns for sulphates (δ(34)S-SO4, δ(18)O-SO4) were carried out, in 2006, 2007 and 2012, and another one was conducted for nitrates (δ(15)N-NO3, δ(18)O-NO3), in 2009, in groundwater bodies in order to trace the origins of each pollutant. The present study identified different pollution sources of dissolved NO3(-) in groundwater using an isotopic composition and quantified the percentage of natural (lithology, chemical and biological processes) and anthropogenic (fertilisers, manure and sewage) SO4(2-) and matched a concentration associated with the percentage in order to determine the NBLs in the basin.

Anoxic bio-electrochemical system for treatment of complex chemical wastewater with simultaneous bioelectricity generation.

Bioelectrochemical treatment system (BET) with anoxic anodic microenvironment was studied with chemical wastewater (CW) in comparison with anoxic treatment (AxT, sequencing batch reactor (SBR)) with same parent anaerobic consortia. BET system documented relatively higher treatment efficiency at higher organic load (5.0 kg COD/m(3)) accounting for COD removal efficiency of (90%) along with nitrate (48%), phosphate (51%), sulphates (68%), colour (63%) and turbidity (90%) removal, compared to AxT operation (COD, 47%; nitrate, 36%; phosphate, 32%; sulphate, 35%; colour, 45% and turbidity, 54%). The self-induced bio-potential developed due to the electrode assembly in BET resulted in effective treatment with simultaneous bioelectricity generation (631 mA/m(2)). AxT operation showed persistent reduction behaviour, while simultaneous redox behaviour was observed with BET indicating balanced electron transfer. BET operation illustrated higher wastewater toxicity reduction compared to the AxT system which documents the variation in bio-electrocatalytic behaviour of same consortia under different microenvironment.