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As a proxy for pollutants that may be simultaneously present in urban wastewater streams, the effects of two microplastics—polystyrene (PS; 10, 80 and 230 μm diameter) and polymethylmethacrylate (PMMA; 10 and 50 μm diameter)—on fertilisation and embryogenesis in the sea urchin Arbacia lixula with co-exposure to the pyrethroid insecticide cypermethrin were investigated. Synergistic or additive effects were not seen for plastic microparticles (50 mg L−1) in combination with cypermethrin (10 and 1000 μg L−1) based on evaluation of skeletal abnormalities or arrested development and death of significant numbers of larvae during the embryotoxicity assay. This behaviour was also apparent for male gametes pretreated with PS and PMMA microplastics and cypermethrin, where a reduction in sperm fertilisation ability was not evidenced. However, a modest reduction in the quality of the offspring was noted, suggesting that there may be some transmissible damage to the zygotes. PMMA microparticles were more readily taken up than PS microparticles, which could suggest surface chemical identity as potentially modulating the affinity of larvae for specific plastics. In contrast, significantly reduced toxicity was noted for the combination of PMMA microparticles and cypermethrin (100 μg L−1), and may be related to less ready desorption of the pyrethroid than PS, as well as cypermethrin activating mechanisms that result in reduced feeding and hence decreased ingestion of microparticles.

The co-occurrence of heavy metals, antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) from hospital effluents spreading into the river receiving systems and evaluating associated risks are topics of scientific interest and still under-studied in developing countries under tropical conditions. To understand the selectors of the ARGs, we examined the occurrence of heavy metals (Cr, Co, Ni, Cu, Cd, Pb and Zn), associated ARB (β-lactam-resistant Escherichia coli, β-lactam-resistant Enterobacteriaceae, and carbapenem-resistant Enterobacteriaceae) and ARGs (blaOXA, blaCTX-M, blaIMP, blaTEM) in water and sediments from two sub-urban rivers receiving urban and hospital effluent waters in the Democratic Republic of the Congo (DRC). High abundances of ARB and ARGs were observed in all sediment samples. All the metal contents correlated negatively with grain size (− 0.94 ≤ r ≤ − 0.54, p r ≤ 0.79, p Enterococcus except for Ni and Cd (0.43 ≤ r ≤ 0.67, p r = − 0.44, p r ≤ 1.0, p

This study aims to investigate the feasibility of treating olive mill waste water (OMWW) by activated sludge pilot (AS) after its high dilution (1%) by urban waste water (UWW) and to study the effect of polyphenol compounds on the biomass during the treatment. Specific oxygen uptake rate (SOUR), mixed liquor volatile suspended solids (MLVSS), chemical oxygen demand (COD) and total polyphenols, were followed up over 100 days. In spite of the polyphenols' high concentration (up to 128 mg·L−1), successful biomass growth of 7.12 g MLVSS.L −1 and activity were achieved. Most of the bacteria (Pseudomonas sp., Klebsiella oxytoca, Citrobacter fereundii, Escherichia coli and Staphylococcus sp.) and fungi (Trichoderma sp., Rhizopus sp., Aspergillus niger, Penicillium sp., Fusarium sp., Alternaria) identified in the aerobic basin during the stabilization stage were known to be resistant to OMWW and showed effective adaptation of the biomass to polyphenols in high concentration. COD and polyphenols were highly eliminated (90%, 92% respectively). The sludge volume index in the pilot settling tank was almost constant at around 120 mL.g −1. This suggests the possibility of managing OMWW by simple injection at a given percentage in already functioning conventional AS treating UWW.

Sludge generated in urban wastewater treatment plants is a huge environmental and economic challenge of sustainability. Sludge recovery is an environmental necessity and is a requirement for wastewater treatment plants. Predators have been proposed as a biological solution and simultaneously obtaining by-product of interest. Nematodes are predators that are found naturally in sludge but have never been proposed for sludge reduction. In this work, Caenorhabditis elegans, a nematode broadly used for biomedical studies, was used to grow on urban sludge, reaching a remarkable average population up to 92,668 nematodes/mL, 50.6% of sludge was converted into nematode biomass and up to 21.0% of organic matter removed. To demonstrate the viability of this nematode to grow and reduce urban sludges, different experiments in solid and liquid culture media were performed. The physio-chemical composition of the different types of sludges generated in the urban wastewater treatment plants was determined. The total lipids (4.52%, w/w) and fatty acid profiles obtained in the nematode biomass were determined. This work presents a new method to valorise urban sludge and opens the possibility to obtain by-products with high added value., This work was partially supported by BEFESA S.L. (ABENGOA) by financing the project entitled “Viability study for obtaining nematodes fat matter from sludge of urban wastewater treatment plants” and the Junta de Andalucia and Ministry of Economy and Competitiveness (Spain), through Project Ref.: AGR-7092 “Application of advanced oxidation technologies for treating of washing wastewaters of olive oil and olives”, which allowed the urban sludge monitoring and results obtained.

A set of CALUX in vitro bioassays was applied for long-term toxicity monitoring at an advanced wastewater treatment plant comprising ozonation and granular activated carbon filtration for the abatement of contaminants of emerging concern (CEC). During the 13-month monitoring, eight reporter gene assays targeting different modes of action along the cellular toxicity pathway were accessed to evaluate the suitability and robustness of the technologies. Two approaches were followed: on the one hand, signal reduction during advanced treatment was monitored, on the other hand, results were compared to currently available effect-based trigger values (EBTs). A decrease of the corresponding biological equivalent concentrations after the multibarrier system could be observed for all modes of action, while the estrogenic activity decreased below the EBT already during ozonation, the potencies of oxidative stress-like and toxic PAH-like compounds still exceeded the discussed EBT after advanced treatment. Overall, the long-term monitoring confirmed the positive effect of the multibarrier system, commonly evaluated only by CEC abatement based on chemical analysis. It could be demonstrated that advanced WWTPs designed for CEC abatement are suitable to significantly decrease toxicity responses not only in the frame of pilot studies but under real-world conditions as well.

Currently, most wastewater treatment plants do not meet the legal requirements, especially regarding phosphorus and nitrogen contents. In this work, real primary urban wastewater (P-UW) was used as culture medium for the growth of Chlorella vulgaris. Experiments were carried out in batch photobioreactors at laboratory scale. To determine the maximum nutrient removal levels and the optimal pH value for C. vulgaris growth, the following pH values were studied: 5, 6, 7, 8, 9, 10, and 11. Additionally, two control experiments were conducted using UW and tap water at the same conditions but without microalgae inoculation. The operational conditions were agitation rate = 200 rpm, T = 25 °C, aeration rate = 0.5 L/min, and continuous light with illumination intensity = 359 µE m−2 s−1. Significant higher growth was obtained at pH = 7. The direct use of C. vulgaris for P-UW treatment demonstrated high removal percentages of organic (COD and BOD5 removal = 63.4% and 92.3%, respectively) and inorganic compounds (inorganic carbon removal = 99.6%). The final biomass was characterized by an accumulation of high energetic compounds, mainly carbohydrates, which ranged between 63.3% (pH = 5) and 82.8% (pH = 11) and represent a source of biofuels. These new achievements open up the possibility of new horizons in urban wastewater treatment.

Pharmaceutically active compounds (PhACs) widely present in urban wastewater effluents pose a threat to ecosystems in the receiving aquatic environment. In this work, efficiency of granular activated carbon (GAC) - based catalytic processes, namely catalytic wet peroxide oxidation (CWPO), peroxymonosulfate oxidation (PMS/GAC) and peroxydisulfate oxidation (PDS/GAC) at ambient temperature and pressure were studied for removal of 22 PhACs (ng L-1 level) that were present in secondary effluents of real urban wastewater. Concentrations of PhACs were measured using Ultra Performance Liquid Chromatography - Triple Quadrupole Mass Spectrometry (UPLC-QqQ-MS/MS). Catalytic experiments were conducted in discontinuous mode using up-flow fixed bed reactors with granular activated carbon (GAC) as a catalyst. The catalyst was characterized by means of N-2 adsorption-desorption isotherm, mercury intrusion porosimetry (MIP), elemental analysis, X-ray fluorescence spectroscopy (WDXRF), X-ray diffraction (XRD), thermal gravimetry and differential temperature analyses coupled mass spectrometry (TGA-DTA-MS). Results indicate that the highest efficiency in terms of TOC removal was achieved during CWPO performed at optimal operational conditions (stoichiometric dose of H2O2; TOC removal similar to 82%) followed by PMS/GAC (initial PMS concentration 100 mg L-1; TOC removal similar to 73.7%) and PDS/GAC (initial PDS concentration 100 mg L-1; TOC removal similar to 67.9%) after 5 min of contact time. Full consumption of oxidants was observed in all cases for CWPO and PDS/GAC at contact times of 2.5 min, while for PMS/GAC it was 1.5 min. In general, for 18 out of 22 target PhACs, very high removal efficiencies (> 92%) were achieved in all tested processes (including adsorption) performed at optimal operational conditions during 5 min of contact time. However, moderate (40 - 70%) and poor (< 40%) removal efficiencies were achieved for salicylic acid, ofloxacin, norfloxacin and ciprofloxacin, which can be possibly attributed to insufficient contact time. Despite high efficiency of all studied processes for PhACs elimination from urban wastewater effluent, CWPO seems to be more promising for continuous operation. (C) 2021 Elsevier Ltd. All rights reserved., Authors are grateful to staffmembers of Viikinmaki Wastewater Treatment Plant (Helsinki, Finland) for collaboration. D.Sc. Juan Jose Rueda-Marquez is thankful for financial support from Academy of Finland within the project "Combination of Advanced Oxidation Processes and Photobiotreatment for Sustainable Resource Recovery and Wastewater Reuse". D.Sc. Irina Levchuk is grateful for financial support obtained from KAUTE saatio(grant number: 201800116). D.Sc. Ana Rey is grateful for financial support from Ministerio de Economia y Competitividad (MINECO)Agencia Estatal de Investigacion (AEI) of Spain through the project CTQ2015-73168-JIN, co-financed by the European Funds for Regional Development (FEDER, UE). D. Sc. Javier Moreno-Andres is grateful for the financial support by the European Union under the 2014-2020 ERDF Operational Programme and by the Department of Economy, Knowledge, Business and University of the Regional Government of Andalusia. Project reference: FEDER-UCA18-108023.

The aim of the present study was to evaluate the capability of an up-flow anammox sludge bed reactor (13 L) of dampening a 10 °C temperature drop at mainstream conditions while operating at constant nitrogen loading rates (0.11 ± 0.01 g N L−1 d−1). The up-flow anammox sludge bed reactor was fed with an aerobically pre-treated mainstream wastewater. The reactor temperature was controlled as to mimic a (realistic) summer-to-winter transition from 20 to 10 °C plus a three months period at 10 °C. During the 350 days of operation, the average nitrogen removal rate remained high (0.10 ± 0.01 g N L−1 d−1), indicating that the 10 °C drop did not affect the overall efficiency of the reactor. This can be explained as anammox activity differed among the different sludge bed sections. At 20 °C, anammox activity was mainly located at the bottom of the sludge bed. At 10 °C, the anammox activity decrease of the bottom sludge bed was compensated by an activity increase within the upper sludge bed sections. The contribution of heterotrophic denitrifying activity to the total nitrogen removal rate was assessed to be 3-to-5 times lower than that of anammox, even at 10 °C. Microbial community of 16S rRNA gene-targeted sequencing analyses resulted in the identification of an uncharacterized Planctomycetes in high numbers. This study demonstrated that the low temperatures should not be an obstacle for the feasibility of anammox bacteria in the main water line of an urban wastewater treatment plant.

[EN] AnMBR technology is a promising alternative to achieve future energy-efficiency and environmental-friendly urban wastewater (UWW) treatment. However, the large amount of dissolved methane lost in the effluent represents a potential high environmental impact that hinder the feasibility of this technology for full-scale applications. The use of degassing membranes (DM) to capture the dissolved methane from AnMBR effluents can be considered as an interesting alternative to solve this problem although further research is required to assess the suitability of this emerging technology. The aim of this study was to assess the effect of operating temperature and hydrodynamics on the capture of dissolved methane from AnMBR effluents by DMs. To this aim, a commercial polydimethylsiloxane (PDMS) DM was coupled to an industrial prototype AnMBR (demonstration scale) treating UWW at ambient temperature. Different operating temperatures have been evaluated: 11, 18, 24 and 30 degrees C. Moreover, the DM was operated at different ratios of liquid flow rate to membrane area (Q(L):A) ranging from 22 to 190 Lh(-1)m(-2) in order to study the resistance of the system to methane permeation. Methane recovery was maximized when temperature raised and Q(L):A was reduced, giving methane recovery efficiencies (MRE) of about 85% at a temperature of 30 degrees C and a Q(L):A of 25 Lh(-1)m(-2). The study showed that high Q(L):A ratios hinder methane recovery by the perturbation of the DM fibers, being this effect intensified at lower temperatures probably due the higher liquid viscosities. Also, the performed fouling evaluation showed that not significant membrane fouling may be expected in the DM unit at the short-term when treating AnMBR effluents. A resistance-in-series model was proposed to predict the overall mass transfer of the system according to operating temperature and Q(L):A, showing that methane capture was controlled by the liquid phase, which represented up to 80-90% of total mass transfer resistance. The energy and environmental evaluation performed in this study revealed that PDMS DMs would enhance energy recovery and environmental feasibility of AnMBR technology for UWW treatment, especially when operating at low temperatures. When MRE was maximized, the combination of AnMBR with DM achieved net energy productions and net greenhouse gas reductions of up to 0.87 kWh and 0.216 kg CO2-eq per m(3) of treated water., This research work was supported by Generalitat Valenciana via Fellowships CPI-16-155 and C12747, as well as the financial aid received from the Ministerio de Economia y Competitividad via Juan de la Cierva Contract FJCI-2014-21616. This research work was also made possible thanks to co-financing by the European Financial Instrument for the Environment (LIFE+) during the implementation of the Project Membrane for ENERGY and WATER RECOVERYY "MEMORY" (LIFE13 ENV/ES/001353).

In a water ozonation process, dissolved organics undergo two reactions at least: direct ozone attack and oxidation with hydroxyl radicals generated from the ozone decomposition. In the particular case of urban wastewater contaminated with pharmaceuticals, competition between these two reactions can be studied through application of gas&ndash, liquid reaction kinetics. However, there is a lack in literature about kinetic modeling of ozone processes in water specially in photocatalytic ozonation. In this work, lumped reactions of ozone and hydroxyl radicals with total organic carbon have been proposed. Urban wastewater containing a mixture of eight pharmaceutical compounds has been used to establish the kinetic model that simulates the mineralization process. The kinetic model is based on a mechanism of free radical and molecular reactions and the knowledge of mass transfer, chemical reaction rate constants, and radiation transfer data. According to the model, both single ozonation and photocatalytic ozonation present two distinct reaction periods characterized by the absence and presence of dissolved ozone. In the first period (less than 10 min), pharmaceuticals mainly disappear by direct ozone reactions and TOC variation due to these compounds has been modeled according to gas&ndash, liquid reaction kinetics through a lumped ozone-pharmaceutical TOC fast second order reaction. The corresponding rate constant of this reaction was found to change with time from 3 &times, 105 to 200 M&minus, 1 s&minus, 1 with Hatta values higher than 0.3. In the second period (nearly 5 h), competition between direct and hydroxyl radical reactions takes place and a kinetic model based on a direct and free radical reaction mechanism is proposed. Main influencing parameters to be known were: Direct ozone reaction rate constant, catalyst quantum yield, and hydroxyl radical scavengers. The first two take values of 0.5 M&minus, 1 and 5 &times, 10&minus, 4 mol&middot, photon&minus, 1, respectively, while a fraction of TOC between 10% and 90% that changes with time was found to possess hydroxyl radical scavenger nature.

The current knowledge on bioaccumulation of emerging contaminants (ECs) in aquatic invertebrates exposed to the realistic environmental concentrations is limited. Even less is known about the effects of chemical pollution exposure on the metabolome of aquatic invertebrates. We conducted an in situ translocation experiment with passive filter-feeding caddisfly larvae (Hydropsyche sp.) in an effluent-influenced river in order to i) unravel the bioaccumulation (and recovery) dynamics of ECs in aquatic invertebrates, and ii) test whether exposure to environmentally realistic concentrations of ECs will translate into metabolic profile changes in the insects. The experiment was carried out at two sites, upstream and downstream of the discharge of an urban wastewater treatment plant effluent. The translocated animals were collected at 2-week intervals for 46 days. Both pharmaceuticals and endocrine disrupting compounds (EDCs) were detected in water (62 and 7 compounds, respectively), whereas in Hydropsyche tissues 5 EDCs accumulated. Overall, specimens from the upstream site translocated to the impacted site reached higher ECs concentrations in their tissues, as a reflection of the contaminants’ water concentrations. However, bioaccumulation was a temporary process susceptible to change under lower contaminant concentrations. Non-targeted metabolite profiling detected fine metabolic changes in translocated Hydropsyche larvae. Both translocations equally induced stress, but it was higher in animals translocated to the impacted site.

[EN] This study aimed to evaluate the feasibility of degassing membrane (DM) technology for recovering dissolved methane from AnMBR effluents. For that purpose, a PDMS membrane module was operated for treating the effluent from an AnMBR prototype-plant, which treated urban wastewater (UWW) at ambient temperature. Different transmembrane pressures and liquid flow rates were applied for evaluating methane recovery efficiency. Maximum methane recoveries were achieved when increasing the vacuum pressure and reducing the liquid flow rate, reaching a maximum methane recovery efficiency of around 80% at a transmembrane pressure (TMP) of 0.8 bars and a treatment flow rate (Q(L)) of 50 L h(-1). The results revealed that the combination of PDMS DMs and AnMBR technology would allow to reduce the energy demand of UWW treatment, achieving net energy productions while reducing greenhouse gas emissions. Optimum operation was determined at a TMP of 0.8 bars and a Q(L) of 150 L h(-1) when combining energy, environmental and economic targets. Under these operating conditions, the combination AnMBR + DM resulted in energy requirements and greenhouse gases emissions of -0.040 kWh and 0.113 kg of CO2-eq per m(3) of treated water, respectively, resulting in a DM payback period of around 10.5 years., This research work was supported by Generalitat Valenciana via the fellowships CPI-16-155 and C12747, as well as the financial aid received from Ministerio de Economia y Competitividad via Juan de la Cierva contract FJCI-2014-21616. This research work was also possible thanks to co-finance of the European financial instrument for the Environment (LIFE+) during the implementation of the Project Membrane for ENERGY and WATER RECOVERY "MEMORY" (LIFE13 ENV/ES/001353).

This work aims to study the use of a powdered activated carbon with magnetic properties as adsorbent to remove common pharmaceuticals in wastewater treatment. This hybrid material was prepared from powdered activated carbon that was combined with iron oxide nanoparticles and was characterized by infrared spectroscopy and X-ray diffractometry. It was also assessed for its adsorption ability using ibuprofen and amoxicillin as model drugs. Under the tested conditions, adsorption equilibrium was reached at 160 min for both drugs, with removal rates of 95% for the former and 90% for the latter. Adsorption data were fit to several adsorption kinetics and isotherm models. the adsorption of ibuprofen seems to follow a pseudo-order n kinetics and fits best the Redlich-Peterson isotherm model, whilst that of amoxicillin shows best fits to the Bangham kinetics and Temkin isotherm models. the new adsorbent also proved to be efficient in an urban wastewater spiked with both drugs and to keep its adsorption ability upon regeneration by desorption. Fundacao para a Ciencia e a Tecnologia (FCT), PortugalPortuguese Foundation for Science and Technology [REEQ/700/CTM/2005] info:eu-repo/semantics/publishedVersion

International audience; In this study, copper oxide (CuO) catalyzed peroxydisulfate (PDS) system was investigated for the inactivation of a broad range of pathogenic microorganisms from urban wastewater. Complete inactivation of Escherichia coli, Enterococcus, F-specific RNA bacteriophages from secondary treated wastewater was achieved after a short time (15-30 min) treatment with CuO (10 g/L) / PDS (1 mM) system, but spores of sulfite-reducing bacteria took 120 min. No bacterial regrowth occurred during storage after treatment. Significant reduction of the pathogens was explained by the generation of the highly selective Cu(III) oxidant, as the predominant reactive species, which could quickly oxidize guanine through a one-electron oxidation pathway. Additionally, the potential of the CuO (10 g/L) / PDS (1 mM) system to inactivate antibiotic-resistant bacteria and antibiotic resistance genes (ARB&Gs) was explored. Sulfamethoxazole-resistant E. coli was used as the model ARB and a 3.2 log of reduction was observed after 10 min of treatment. A considerable reduction (0.7-2.3 log) of selected ARGs including blaTEM, qnrS, emrB, sul1, and genes related to the dissemination of antibiotic resistance, including the Class 1 integron-integrase (intI1), and the insertion sequence (IS613) was achieved after 60 min treatment. All these findings indicated the promising applicability of the CuO/PDS system as a disinfection technology for wastewater reuse in agriculture.

Human biomonitoring, i.e. the determination of chemicals and/or their metabolites in human specimens, is the most common and potent tool for assessing human exposure to pesticides, but it suffers from limitations such as high costs and biases in sampling. Wastewater-based epidemiology (WBE) is an innovative approach based on the chemical analysis of specific human metabolic excretion products (biomarkers) in wastewater, and provides objective and real-time information on xenobiotics directly or indirectly ingested by a population. This study applied the WBE approach for the first time to evaluate human exposure to pesticides in eight cities across Europe. 24 h-composite wastewater samples were collected from the main wastewater treatment plants and analyzed for urinary metabolites of three classes of pesticides, namely triazines, organophosphates and pyrethroids, by liquid chromatography-tandem mass spectrometry. The mass loads (mg/day/1000 inhabitants) were highest for organophosphates and lowest for triazines. Different patterns were observed among the cities and for the various classes of pesticides. Population weighted loads of specific biomarkers indicated higher exposure in Castellon, Milan, Copenhagen and Bristol for pyrethroids, and in Castellon, Bristol and Zurich for organophosphates. The lowest mass loads (mg/day/1000 inhabitants) were found in Utrecht and Oslo. These results were in agreement with several national statistics related to pesticides exposure such as pesticides sales. The daily intake of pyrethroids was estimated in each city and it was found to exceed the acceptable daily intake (ADI) only in one city (Castellon, Spain). This was the first large-scale application of WBE to monitor population exposure to pesticides. The results indicated that WBE can give new information about the "average exposure" of the population to pesticides, and is a useful complementary biomonitoring tool to study population-wide exposure to pesticides. (C) 2017 Elsevier Ltd. All rights reserved.

Heterogeneous photocatalysis (HPC) has been widely investigated in recent decades for the removal of a number of contaminants from aqueous matrices, but its application in real wastewater treatment at full scale is still scarce. Indeed, process and technological limitations have made HPC uncompetitive with respect to consolidated processes/technologies so far. In this manuscript, these issues are critically discussed and reviewed with the aim of providing the reader with a realistic picture of the prospective application of HPC in wastewater treatment. Accordingly, consolidated and new photocatalysts (among which the visible active ones are attracting increasing interest among the scientific community), along with preparation methods, are reviewed to understand whether, with increased process efficiency, these methods can be realistically and competitively developed at industrial scale. Precipitation is considered as an attractive method for photocatalyst preparation at the industrial scale; sol-gel and ultrasound may be feasible only if no expensive metal precursor is used, while hydrothermal and solution combustion synthesis are expected to be difficult (expensive) to scale up. The application of HPC in urban and industrial wastewater treatment and possible energy recovery by hydrogen production are discussed in terms of current limitations and future prospects. Despite the fact that HPC has been studied for the removal of pollutants in aqueous matrices for two decades, its use in wastewater treatment is still at a "technological research" stage. In order to accelerate the adoption of HPC at full scale, it is advisable to focus on investigations under real conditions and on developing/improving pilot-scale reactors to better investigate scale-up conditions and the potential to successfully address specific challenges in wastewater treatment through HPC. In realistic terms, the prospective use of HPC is more likely as a tertiary treatment of wastewater, particularly if more stringent regulations come into force, than as pretreatment for industrial wastewater to improve biodegradability.

This is the accepted manuscript of the following article: Espíndola et al. Science of the Total Environment, 2019, 667, 197-207. https://doi.org/10.1016/j.scitotenv.2019.02.335 An innovative photoreactor, FluHelik, was used to promote the degradation of contaminants of emerging concern (CECs) by a photochemical UVC/H2O2 process. First, the system was optimized for the oxidation of a model antibiotic, oxytetracycline (OTC), using both ultrapure water (UPW) and a real urban wastewater (UWW) (collected after secondary treatment) as solution matrices. Following, the process was evaluated for the treatment of a UWW spiked with a mixture of OTC and 10 different pharmaceuticals established by the Swiss legislation at residual concentrations (∑CECs

Endocrine disrupting compounds (EDCs) and pharmaceutical residues are environmental ubiquitous contaminants of particular concern due to their possible ecotoxicological effects on aquatic ecosystems. In this work, the occurrence and fate of six antibiotics (amoxicillin, ciprofloxacin, tylosin, erithromycin, sulfamethoxazole and chlortetracycline) and four phenolic endocrine disrupting compounds (EDCs, i.e. bisphenol A, 4-nonylphenol, nonylphenol mono- and di-ethoxylate) in the influents and effluents of the principal wastewater treatment plants (WWTPs) serving the city of Rome (Italy) were investigated. The aim of the study was to provide information on the persistence of the selected contaminants in the urban WWTPs, to evaluate the removal efficiencies of the investigated plants and to perform a preliminary assessment of the potential ecological risk due to the discharge through the effluents of the residual pollutants into the receiving river waters. The analytes were extracted/concentrated from 24-h composite wastewater samples by solid phase extraction (SPE), and the analytical determination was carried out by HPLC MS-MS for the antibiotics and by HPLC-fluorescence detection for the EDCs. All the contaminants were detected both in the inlet and outlet samples of the WWTPs investigated, with the only exception of the antibiotics tylosin and erythromycin. Overall, the results confirmed that the biological treatments were not able to completely remove either the antibiotic residues or the phenolic EDCs selected with removal efficiencies varying widely in the range 17–96%. As a consequence, concentration values in the effluents ranged from 6 to 897 ng/L for antibiotics and from 0.4 to 205 ng/L for phenolic EDCs, with the highest concentrations detected for chlortetracycline and amoxicillin. Indeed, the highest mass loads (mg/d/1000 inhabitants) discharged daily into the receiving waters were found for these latter antibiotics, probably due to their greater consumption by the resident population, while the lowest removal efficiencies in the WWTPs overall were found for sulfamethoxazole and ciprofloxacin, which thus proved to be the most persistent antibiotics in secondary wastewater treatments. Among the EDCs, bisphenol A and nonylphenol di-ethoxylate occurred at higher concentrations in the effluents, mostly in the WWTPs collecting a mix of urban and industrial wastes. The preliminary environmental risk analysis indicated that, although a dilution of the contaminants could potentially occur, an ecotoxicological risk, once they were in the receiving waters, could not be excluded, especially for the antibiotic residues, while it was found that for the phenolic EDCs the risk for the aquatic environment was quite minor.

Solar photo-Fenton process in raceway pond reactors was investigated at neutral pH as a sustainable tertiary treatment of real urban wastewater. In particular, the effect on antibiotic resistance determinants was evaluated. An effective inactivation of different wild bacterial populations was achieved considering total and cefotaxime resistant bacteria. The detection limit (1 CFU mL−1) was achieved in the range 80–100 min (5.4–6.7 kJ L−1 of cumulative solar energy required) for Total Coliforms (TC) (40–60 min for resistant TC, 4.3–5.2 kJ L−1), 60–80 min (4.5–5.4 kJ L−1) for Escherichia coli (E. coli) (40 min for resistant E. coli, 4.1–4.7 kJ L−1) and 40–60 min (3.9–4.5 kJ L−1) for Enterococcus sp. (Entero) (30–40 min for resistant Entero, 3.2–3.8 kJ L−1) with 20 mg L−1 Fe2+ and 50 mg L−1 H2O2. Under these mild oxidation conditions, 7 out of the 10 detected antibiotics were effectively removed (60–100%). As the removal of antibiotic resistance genes (ARGs) is of concern, no conclusive results were obtained, as sulfonamide resistance gene was reduced to some extent (relative abundance

Algal based wastewater treatment offers the opportunity to recover, in the form of biomass, the nutrients and internal chemical energy of wastewater. Recently, there has been a growing interest in the use of extremophilic microalgae, as they can easily adapt to difficult and often pollutant-rich environments. The thermo-acidophilic microalga Galdieria phlegrea is a species of recent discovery and great metabolic versatility, but it has still been poorly studied. Here, G. phlegrea was cultivated using raw municipal wastewater in 1 L Erlenmeyer flasks with 700 mL working volume at 37 °C for up to nine days. During the cultivation phase, biomass growth, phycocyanin content, ammonium and phosphate removal from the wastewater, lipid fraction, total carbon and nitrogen in the biomass, and variation in δ13C and δ15N isotopic ratios (a novel analytical contribution in these experiments) were monitored. Results indicated that G. phlegrea was able to grow in raw effluent, where it removed more than 50% ammonium and 20% phosphate in 24 h, total lipid content was in the range of 11–22%, while average C-N content was of 45% and 6%, respectively, isotopic analyses proved to be a useful support in identifying C and N metabolic pathways from effluent to biomass. Overall, G. phlegrea showed consistent performance with similar Cyanidiophyceae and is a potentially viable candidate for municipal wastewater valorization from a circular economy perspective.

Solar-driven advanced oxidation processes were studied in a pilot-scale photoreactor, as tertiary treatments of effluents from an urban wastewater treatment plant. Solar-H2O2, heterogeneous photocatalysis (with and/or without the addition of H2O2 and employing three different photocatalysts) and the photo-Fenton process were investigated. Chemical (sulfamethoxazole, carbamazepine, and diclofenac) and biological contaminants (faecal contamination indicators, their antibiotic resistant counterparts, 16S rRNA and antibiotic resistance genes), as well as the whole bacterial community, were characterized.& para;& para;Heterogeneous photocatalysis using TiO2-P25 and assisted with H2O2 (P25/H2O2) was the most efficient process on the degradation of the chemical organic micropollutants, attaining levels below the limits of quantification in less than 4 h of treatment (corresponding to Q(UV)

The occurrence of antibiotics in urban wastewater treatment plants (UWTPs) may result in the development of antibiotic resistance and subsequently in the release of multidrug resistant bacteria (MDR) and genes into the effluent. Conventional disinfection processes are only partially effective in controlling ARB spread, so advanced oxidation processes (AOPs) have been investigated as alternative option in this work. In particular, the aim of this work was to comparatively assess the efficiency of solar disinfection and solar driven AOPs (namely H 2 O 2 /sunlight, TiO 2 /sunlight, H 2 O 2 /TiO 2 /sunlight, natural photo-Fenton) for the inactivation of a multidrug (namely ampicillin, ciprofloxacin and tetracycline) resistant E. coli strain isolated from the effluent of the biological process of an UWTP. Different concentrations of H 2 O 2 (0.588–1.470–2.205 mM), TiO 2 (50–100 mg L −1 ), H 2 O 2 /TiO 2 (0.147 mM/50 mg L −1 , 0.588 mM/100 mg L −1 ) and Fe 2+ /H 2 O 2 (0.090/0.294, 0.179/0.588, 0.358/1.176 mM) were evaluated at pilot-scale (in compound parabolic collector reactor) in real biologically treated wastewater. All investigated processes resulted in a complete inactivation (5-log decrease) of bacteria until detection limit, but the best disinfection efficiency in terms of treatment time (20 min to reach the detection limit) and required energy (0.98 kJ L −1 ) was observed for photo-Fenton at pH 4 (Fe 2+ /H 2 O 2 :0.090/0.294 mM). Antimicrobial susceptibility was tested by Kirby-Bauer disk diffusion method. Ampicillin and ciprofloxacin (to which the selected strain is resistant), cefuroxime and nitrofurantoin were chosen as tested antibiotics. None of the investigated processes affected antibiotic resistance of survived colonies.

In Italy, urban wastewater disinfection is regulated in the third part of Legislative Decree n. 152/2006, which states that wastewater treatment plants (WWTPs) must include a disinfection unit, with a capacity exceeding 2000 Population Equivalent (PE). This treatment shall ensure microbial quality and health security. The legislation provides the following limits for wastewater: Escherichia coli (E. coli) concentration below 5000 CFU 100 mL−1 (recommended value), active chlorine concentration below 0.2 mg L−1 and lack of acute toxicity. The compliance with these conditions is shown by means of the study of correct disinfectant dosage, which also depends on wastewater characteristics. An investigation at the regional level (from 2013 to 2016) shows a correlation between acute toxicity discharge and disinfection treatment through chemical reagents (mainly with the use of chlorine compounds and peracetic acid). The experimental work concerns two active sludge WWTPs in northern Italy with small capacity (10,000–12,000 PE). The activities provide the assessment of microbiological quality and toxicity of WWTPs effluents in relation to the dosage of sodium hypochlorite and peracetic acid, by means of the use of batch tests. The results show that with similar disinfectant dosage and comparable initial E. coli concentration, peracetic acid exhibits the best performance in terms of microbial removal (with removal yields up to 99.99%). Moreover, the acute toxicity was evident at higher doses and therefore with higher residuals of peracetic acid (2.68 mg L−1) compared to the free residual chlorine (0.17 mg L−1).

In this study, a series of photocatalysts based on TiO2 was tested in the elimination of Escherichia coli (E. coli) from urban wastewater. Firstly, TiO2 obtained by sol-gel method was modified by sulfation, and then gold or platinum nanoparticles were photodeposited on sulfated titania surface. Platinized samples were also prepared with different Pt content of 0.5 and 2 wt.%. The samples thus obtained were extensively characterized and it was found that sulfation considerably increases the SBET value of TiO2 and promotes the anatase phase formation; it was also found that 0.5 wt.% Pt-TiO2 sample presents the lowest noble metal particle size and the best particle dispersion. All the photocatalysts synthesized have shown bactericidal effect and the results obtained by using bare and metalized TiO2 were considerably better than the results obtained with the commercial TiO2 P25 Evonic. Different light intensities were also evaluated in the photocatalytic tests and it was found that 120 W/m2 leads to obtain the highest E. coli elimination from wastewater samples; however no total elimination of E. coli or other species of bacteria was achieved even after 5 h of photocatalytic treatment without catalyst. Total elimination of the E. coli was achieved after 3 h of photocatalytic reaction by using 120 W/m2 of light intensity and 2 wt.% Pt-TiO2 as photocatalyst; no bacterial regrowth was observed even after 72 h., Universidad Pedagógica y Tecnológica de Colombia is acknowledged for the financial support of this research. E.G. Ávila-Martínez would like to thank Colciencias for the concession of a young researcher grant 2015. Funding received from the Spanish Ministry of Economy and Competitiveness is appreciated throughout the Project Reference CTQ2015-64664-C2-2-P.

CAPS is the acronym for chemically assisted primary sedimentation, which consists of adding chemicals to raw urban wastewater to increase the efficacy of coagulation, flocculation and sedimentation. The principal benefits of CAPS are: upgrading of urban wastewater treatment plants; increasing efficacy of primary sedimentation; and the major production of energy from the anaerobic digestion of primary sludge. Metal coagulants are usually used because they are both effective and cheap, but they can cause damage to the biological processes of anaerobic digestion. Generally, biodegradable compounds do not have these drawbacks, but they are comparatively more expensive. Both metal coagulants and biodegradable compounds have preferential and penalizing properties in terms of CAPS application. The problem can be solved by means of a multi-criteria analysis. For this purpose, a series of tests was performed in order to compare the efficacy of several organic and mixed-organic polymers with that of polyaluminium chloride (PACl) under specific conditions. The multi-criteria analysis was carried out coupling the simple additive weighting method with the paired comparison technique as a tool to evaluate the criteria priorities. Five criteria with the following priorities were used: chemical oxygen demand (COD) removalturbidity, SV60coagulant dose, and coagulant cost. The PACl was the best alternative in 70% of the cases. The CAPS process using PACl made it possible to obtain an average COD removal of 68% compared with 38% obtained, on average, with natural sedimentation and 61% obtained, on average, with the best PACl alternatives (cationic polyacrylamide, natural cationic polymer, dicyandiamide resin).

An experimental hybrid system based on an anaerobic reactor followed by three stages of different constructed wetland configurations was evaluated when operating under a high hydraulic loading rate (HLR = 0.27 m d-1, considering the area of the VF beds) for one year, which corresponds to four times the nominal hydraulic loading rate, with the purpose of reducing the specific area required. Moreover, in order to assess its buffer capacity, a major storm event was simulated by increasing the HLR 10 times during 1 h. A tracer experiment was also performed to determine the experimental hydraulic retention time (HRT). The system consisted of a hydrolytic upflow sludge blanket (HUSB) reactor followed by two alternating 1.5 m2 vertical subsurface flow, a 2 m2 horizontal subsurface flow and a 2 m2 free water surface constructed wetlands operating in series. The system achieved very high values of removal of solids, organic matter and nutrients (82, 93, 96 and 75% for COD, BOD5, TSS and NH4-N, respectively). Removal of PO4-P and SO42- were though fairly low, of 11 and 10%, respectively. There was a seasonal effect in the system for parameters whose removal highly depends on biodegradation, being enhanced under warmer conditions (98 and 92% removal of BOD5 and NH4-N in summer vs. 87 and 67% removal of BOD5 and NH4-N in winter). The experimental HRT of the entire system was of about 38 h, which is greater than the theoretical HRT (28 h). During the simulation of the storm event removal efficiencies did not vary significantly from the ones obtained under normal conditions (average of 83, 99 and 80% for COD, TSS and NH4-N removal, respectively). The system showed a very good buffer capacity coping with sharp fluctuations in flow to be treated, showing to be an adequate solution for wastewater treatment in small communities. The specific area requirement under the long-term operation showed to be as low as 2 m2/PE.

The present paper presents a submerged anaerobic membrane bioreactor (SAnMBR) as a sustainable approach for urban wastewater treatment at 33 and 20 C, since greenhouse gas emissions are reduced and energy recovery is enhanced. Compared to other anaerobic systems, such as UASB reactors, the membrane technology allows the use of biogas-assisted mixing which enhances the methane stripping from the liquid phase bulk. The methane saturation index obtained for the whole period (1.00 ± 0.04) evidenced that the equilibrium condition was reached and the methane loss with the effluent was reduced. The methane recovery efficiency obtained at 20 C (53.6%) was slightly lower than at 33 C (57.4%) due to a reduction of the treatment efficiency, as evidenced by the lower methane production and the higher waste sludge per litre of treated wastewater. For both operational temperatures, the methane recovery efficiency was strongly affected by the high sulphate concentration in the influent wastewater., This research work has been supported by the Spanish Research Foundation (CICYT Projects CTM2008-06809-C02-01 and CTM2008-06809-C02-02) and the Comunidad Valenciana Regional Government (GVACOMP2009-285), which are gratefully acknowledged.

This work illustrates the potential of hybrid quadrupole-time-of-flight mass spectrometry (QTOF MS) coupled to ultrahigh pressure liquid chromatography (UHPLC) to investigate the presence of drugs of abuse in wastewater. After solid-phase extraction with Oasis MCX cartridges, seventy-six illicit drugs, prescription drugs with potential for abuse, and metabolites were investigated in the samples by TOF MS using electrospray interface under positive ionization mode, with MS data acquired over an m/z range of 50–1000 Da. For 11 compounds, reference standards were available, and experimental data (e.g., retention time and fragmentation data) could be obtained, facilitating a more confident identification. The use of a QTOF instrument enabled the simultaneous application of two acquisition functions with different collision energies: a low energy (LE) function, where none or poor fragmentation took place, and a high energy (HE) function, where fragmentation in the collision cell was promoted. This approach, known as MSE, enabled the simultaneous acquisition of full-spectrum accurate mass data of both protonated molecules and fragment ions in a single injection, providing relevant information that facilitates the rapid detection and reliable identification of these emerging contaminants in the sample matrices analyzed. In addition, isomeric compounds, like the opiates, morphine and norcodeine, could be discriminated by their specific fragments observed in HE TOF MS spectra, without the need of reference standards. UHPLC–QTOF MS was proven to be a powerful and efficient technique for rapid wide-scope screening and identification of many relevant drugs in complex matrices, such as influent and effluent urban wastewater. This work has been developed under financial support provided by the University Jaume I-Fundación Bancaixa (project reference: P1 1B2007-13) and the Spanish Ministry of Education and Science (projects reference: CTQ2009-12347 and CTM2006-07711)

A continuous injection experiment was implemented in a pilot-scale horizontal subsurface flow constructed wetland system to evaluate the behavior of four pharmaceuticals and personal care products (i.e. ibuprofen, naproxen, diclofenac and tonalide) and a phenolic estrogenic compound (i.e. bisphenol A). The treatment system consisted of an anaerobic reactor as a primary treatment, followed by two 0.65 m2 wetlands (B1 and B2) working in parallel and connected to a 1.65 m2 wetland (B3) operating in series. Overall removal efficiencies for the selected compounds ranged from 97% to 99%. The response curves of the injected pollutants show that the behavior of these compounds strongly depends on their sorption and biodegradation characteristics. While about 50% of ibuprofen was removed in B1 and B2, 99% was achieved at B3, where the dissolved oxygen concentration was significantly higher (B1–B2 = 0.5 mg L−1 and B3 = 5.4 mg L−1). Naproxen and diclofenac were efficiently removed (93%) in B1 and B2, revealing anaerobic degradation as a probable removal mechanism. Moreover, tonalide and bisphenol A were readily removed in the small wetlands (94% and 83%, respectively), where the removal of total suspended solids was 93%. Therefore, given their high hydrophobicity, sorption onto the particulate matter stands for the major removal mechanism. However, the tentative identification of carboxy-bisphenol A as an intermediate degradation product in B3 suggested biodegradation as a relevant bisphenol A removal pathway under aerobic prevailing conditions., This research has been funded by the Spanish Ministry of Innovation and Science for the NEWWET2008 Project Nos. CTM2008-06676-C05-01 and CTM2008-06676-C05-04, and partially by the Spanish Ministry of Environment (MMARM) through the Project No. 085/RN08/03.2. Ms. C.A. kindly acknowledges a predoctoral fellowship from the Technical University of Catalonia and Ms. A.P. acknowledges the Spanish Ministry of Innovation and Science for the scholarship. Dr. V.M. acknowledges a Juan de la Cierva contract.

The application of sonolysis (US) for remediation of wastewater is an area of increasing interest. The aim of this study was to evaluate the ultrasonic (US) process on the degradation of pharmaceuticals (diclofenac (DCF), amoxicillin (AMX), carbamazepine (CBZ)) in single solutions and also in three mixtures spiked in urban wastewater effluent. Several operating conditions, such as power density (25–100 W L −1 ), initial substrate concentrations (2.5–10 mg L −1 ), initial solution pH (3–11), and air sparging were varied for the evaluation and understanding of the process. The degradation (as assessed by measuring UV absorbance), the generation of hydroxyl radicals (as assessed measuring H 2 O 2 concentration), the mineralization (in terms of TOC and COD removal), and the aerobic biodegradability (as assessed by the BOD 5 /COD ratio) were monitored during sonication. Ecotoxicity to Daphnia magna , Pseudokirchneriella subcapitata and Lepidium sativum before and after treatment was also evaluated. It was found that the pharmaceuticals conversion is enhanced at increased applied power densities, acidic conditions and in the presence of dissolved air. The reaction rate increases with increasing initial concentration of single pharmaceuticals but it remains constant in the mixtures, indicating different kinetic regimes (i.e. first and zero order respectively). Mineralization is a slow process as reaction by-products are more stable than pharmaceuticals to total oxidation; nonetheless, they are also more readily biodegradable. The toxicity of the wastewater samples before and after contamination with pharmaceuticals both in mixtures and in single substance-containing solutions was observed more severely on P. subcapitata ; a fact that raises concerns in regards to the discharge of such effluents. D. magna displayed less sensitivity compared to P. subcapitata because it belongs in a lower taxonomic species than D. magna . The germination index of L. sativum in the presence of the drugs' mixture was stimulated instead of inducing any toxicity effect and this might be attributed to the fact the sample, laden with very low drug concentrations was able to act as a provider of additional nutrient elements.

Sewers are known as longitudinal reactors where gases such as methane, nitrous oxide and hydrogen sulphide can be produced. However, gaseous emissions have been mainly assessed in wastewater treatment plants (WWTP). This article presents a critical review of studies that quantify the generation of these gases in sewers and aims to identify the existing research gaps. Differences in sampling methods and site selection, as well as a limited number of studies, result in incoherent comparisons. To address some of these gaps, sampling campaigns were conducted in two Spanish cities. Results showed that wet wells were the most important sources of gases with concentrations up to 321 μg CH4 Lair−1 and 6.8 μg N2O Lair−1. Regarding emission factors, in the case of Calafell, the estimated annual emissions were 18.6 kg CH4 year−1 and 0.3 kg H2S year−1 in summer and 3.8 kg CH4 year−1 and 0.5 kg H2S year−1 in winter. About Betanzos, these values were 24.6 kg CH4 year−1 and 0.5 kg N2O year−1 in summer and 10 kg CH4 year−1 in winter. The summer campaign resulted in greater gas concentration than in the winter season for both cities, suggesting that temperature is a key parameter. We conclude that gas emissions from sewers are significant compared to those of WWTPs resulting in an important contribution to the carbon footprint. Further work needs to be done to assess the gas production along the entire sewer networks, which can result in very different emission factors depending on the sewer components.

PubMed ID: 25632904 Assessment of water pollution and its effect upon river biotic communities and human health is indispensable to develop control and management strategies. In this study, the mutagenicity and genotoxicity of urban wastewater of the city of Guelma in Algeria were examined between April 2012 and April 2013. For this, two biological tests, namely Amesand chromosomal aberrations (CA) test in Allium cepa root tips were employed on the samples collected from five different sampling stages (S1–S5). In Ames test, two strains of Salmonella typhimurium TA98 and TA100 with or without metabolic activation (S9-mix) were used. All water samples were found to be mutagenic to S. typhimurium TA98 with or without S9-mix. A significant decrease in mitotic index (MI) was observed with a decrease in the percentage of cells in the prophase and an increase in the telophase. Main aberrations observed were anaphase bridges, disturbed anaphase-telophase cells, vagrants and stickiness in anaphase-telophase cells. All treatments of wastewater in April 2012, at S5 in July 2012, at S1 and S5 in November 2012, at S5 in February 2013, and at S1 in April 2013 induced CA when compared to the negative control. Some physicochemical parameters and heavy metals (Cd, Pb, and Cu) were also recorded in the samples examined. © 2015, Springer International Publishing Switzerland.

International audience; The occurrence in urban wastewater of eight micropollutants (erythromycin, ibuprofen, 4-nonylphenol (4-NP), ofloxacin, sucralose, tridosan, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS)) originating from household activities and their fate in a biological wastewater treatment plant (WWTP) were investigated. Their concentrations were assessed in the liquid and solid phases (sewage particulate matter and wasted activated sludge (WAS)) by liquid chromatography-tandem mass spectrometry.The analysis of sewage from two different urban catchments connected to the WWTP showed a specific use of ofloxacin in the mixed catchment due to the presence of a hospital, and higher concentrations of sucralose in the residential area.The WWTP process removed over 90% of ibuprofen and triclosan from wastewater, while only 25% of ofloxacin was eliminated. Erythromycin, sucralose and PFOA were not removed from wastewater, the influent and effluent concentrations remaining at about 0.7 mu g/L, 3 mu g/L and 10 ng/L respectively. The behavior of PFOS and 4-nonylphenol was singular, as concentrations were higher at the WWTP outlet than at its inlet. This was probably related to the degradation of some of their precursors (such as alkylphenol ethoxylates and polyfluorinated compounds resulting in 4-NP and PFOS, respectively) during biological treatment.4-NP, ofloxacin, triclosan and perfluorinated compounds were found adsorbed on WAS (from 5 ng/kg for PFOA to 1.0 mg/kg for triclosan).The statistical methods (principal component analysis and multiple linear regressions) were applied to examine relationships among the concentrations of micropollutants and macropollutants (COD, ammonium, turbidity) entering and leaving the WWTP. A strong relationship with ammonium indicated that some micropollutants enter wastewater via human urine. A statistical analysis of WWTP operation gave a model for estimating micropollutant output from the WWTP based on a measurement of macropollution parameters. (C) 2014 Elsevier B.V. All rights reserved.

Rapid and sensitive analytical methodology based on ultra high-performance liquid chromatography-tandem mass spectrometry has been developed for the determination of widely consumed drugs of abuse (amphetamines, MDMA, cocaine, opioids, cannabis and ketamine) and their major metabolites in urban wastewaters. Sample clean-up and pre-concentration was performed by a generic off-line SPE procedure using Oasis HLB. Special effort was made to incorporate amphetamine, which was found highly problematic in the wastewater samples tested, including an additional clean-up with Oasis MCX SPE and dispersive primary secondary amine. Correction for possible SPE losses or degradation during storage was made by the use of isotope-labelled internal standards (ILIS), available for all compounds, which were added to the samples as surrogates. Although ILIS were also efficient for matrix effects correction, the strong ionization suppression observed was not eliminated; therefore, a four-fold dilution prior to SPE was applied to influent wastewaters and a low injection volume was selected (3 μL), in order to reach a compromise between matrix effects, chromatographic performance and sensitivity. The method was validated at 25 and 200 ng L(-1) (effluent), and 100 and 800 ng L(-1) (influent), obtaining limits of quantification (i.e. the lowest level that the compound can be quantified and also confirmed with at least two MS/MS transitions) between 0.4-25 ng L(-1) (effluent) and 2-100 ng L(-1) (influent). The applicability of the method was demonstrated by analysis of 14 influent and 14 effluent wastewater samples collected over 2 weeks in Castellón (Spain) within a European collaborative study.

Discharge of silver nanoparticles (AgNP) from textiles and cosmetics, todays major application areas for metallic AgNP, into wastewater is inevitable. Transformation in wastewater treatment plants (WWTP) will determine the impact of AgNP on aquatic and terrestrial environments. This study aimed to determine the behavior of AgNP in the sludge at the WWTP by adressing the stability of citrate- coated AgNPs and their interactions with laundry-relevant surfactants (sodium dodecyl sulphate (SDS) and dodecylammonium chloride (DDACl)). The stability of the AgNPs was shown to depend on the charge and concentration of the adsorbed surfactants. The presence of DDACl prevented the formation of AgNP agglomerates even at higher ionic strength. In order to determine the effect of AgNP on biodegradation of laundry surfactants, we employed standardized method for water quality and HRN- EN-ISO-10707:2000 (Evaluation in an aqueous medium of the "ultimate" aerobic biodegradability of organic compounds). Additionally, we evaluated the inhibitory effect of AgNPs on the growth of activated sludge microorganisms (ASMs)). Results showed that AgNPs were toxic to ASMs at very high concentration (>50 mg/L). However, biodegradability of SDS, DDACl and commercial laundry detergent were inhibited by more than 5% and 20% in the presence of 0.1 and 1 mg/L AgNP, respectively. It can be concluded that AgNP discharged to the wastewater stream will influenced overall biodegradability of organic matter at various degrees in the sewer system. Such knowledge is important as it may influence the subsequent transport of AgNPs through different chemical transients and thus their potential bioavailability and toxicity.

The ability of bacteria isolated from a fixed-film bioreactor to precipitate phosphate crystals for the treatment of domestic wastewater in both artificial and natural media was studied. When this was demonstrated in artificial solid media for crystal formation, precipitation took place rapidly, and crystal formation began 3 days after inoculation. The percentage of phosphate-forming bacteria was slightly higher than 75%. Twelve major colonies with phosphate precipitation capacity were the dominant heterotrophic platable bacteria growing aerobically in artificial media. According to their taxonomic affiliations (based on partial sequencing of the 16S rRNA), the 12 strains belonged to the following genera of Gram-negative bacteria: Rhodobacter, Pseudoxanthobacter, Escherichia, Alcaligenes, Roseobacter, Ochrobactrum, Agromyce, Sphingomonas and Paracoccus. The phylogenetic tree shows that most of the identified populations were evolutionarily related to the Alphaproteobacteria (91.66% of sequences). The minerals formed were studied by X-ray diffraction, scanning electron microscopy (SEM), and energy dispersive X-ray microanalysis (EDX). All of these strains formed phosphate crystals and precipitated struvite (MgNH4PO4·6H2O), bobierrite [Mg3(PO4)2·8H2O] and baricite [(MgFe)3(PO4)2·8H2O]. The results obtained in this study show that struvite and spherulite crystals did not show any cell marks. Moreover, phosphate precipitation was observed in the bacterial mass but also near the colonies. Our results suggest that the microbial population contributed to phosphate precipitation by changing the media as a consequence of their metabolic activity. Moreover, the results of this research suggest that bacteria play an active role in the mineral precipitation of soluble phosphate from urban wastewater in submerged fixed-film bioreactors., This investigation was funded by the CTM 2009-11929-CO2-02 of the Spanish Ministerio de Educación y Ciencia.

This work was aimed at studying the effect of light–darkness and high–low biomass concentrations in the feasibility of removing nitrogen and phosphorus from urban treated wastewater by the microalga Scenedesmus obliquus . Laboratory experiments were conducted in batch, where microalgae were cultured under different initial biomass concentrations (150 and 1500 mg SS l −1 ) and light conditions (dark or illuminated). Nutrient uptake was more dependent on internal nutrient content of the biomass than on light presence or biomass concentration. When a maximum nitrogen or phosphorus content in the biomass was reached (around 8% and 2%, respectively), the removal of that nutrient was almost stopped. Biomass concentration affected more than light presence on the nutrient removal rate, increasing significantly with its increase. Light was only required to remove nutrients when the maximum nutrient storage capacity of the cells was reached and further growth was therefore needed. Residence times to maintain a stable biomass concentration, avoiding the washout of the reactor, were much higher than those needed to remove the nutrients from the wastewater. This ability to remove nutrients in the absence of light could lead to new configurations of reactors aimed to wastewater treatment.

This article proposes a kinetic model for wastewater photobiotreatment with microalgae (the PhBT model). The PhBT model for nutrient uptake, coupled with the Verhulst growth model, is a simple and useful tool to describe batch experiments of nutrient removal by microalgae. The model has been validated with experiments of Chlorella vulgaris (C. vulgaris) grown in wastewater and different synthetic media. The model provided information about nitrogen and phosphorus limitation and their luxury uptake during the test. Productivity observed in synthetic medium (0.17 g SS L(-1) d(-1)) was similar to that obtained in nutrient enriched wastewater (0.15 g SS L(-1) d(-1)). Biomass productivity of this alga in wastewater and the efficient nutrient removal suggested that C. vulgaris could be cultured in wastewater for biomass production while nutrients are reduced from this stream.

Chemically Assisted Primary Sedimentation (CAPS) consists of adding chemicals in order to increase the coagulation, flocculation and sedimentation of raw urban wastewater. The CAPS process can be developed in order to increase the efficacy of primary sedimentation as well as avoid any interference with biological treatment processes. The application of CAPS is particularly suitable as a technique for the upgrading of urban wastewater treatment plants (UWWTPs). In fact, CAPS does not require any further significant structural intervention (so saving investment costs and territory portions). The aim of this contribution is to emphasise the role of CAPS as a green chemistry option available in a UWWTP. In particular, a specific aim of the chapter is to focus the attention on the energetic importance of CAPS due to its capacity to increase the production of the primary sludge and consequently the energy production with an anaerobic digestion treating separately primary and secondary sludge. The energetic convenience and “green” propensity of the application of CAPS is discussed by means of the presentation of a paradigmatic case study containing economic evaluations, as well.

This review focuses on 118 pharmaceuticals, belonging to seventeen different therapeutic classes, detected in raw urban wastewater and effluent from an activated sludge system, a usual treatment adopted for urban wastewaters worldwide prior to final discharge into surface water bodies. Data pertaining to 244 conventional activated sludge systems and 20 membrane biological reactors are analysed and the observed ranges of variability of each selected compound in their influent and effluent reported, with particular reference to the substances detected most frequently and in higher concentrations. A snapshot of the ability of these systems to remove such compounds is provided by comparing their global removal efficiencies for each substance. Where possible, the study then evaluates the average daily mass load of the majority of detected pharmaceuticals exiting the secondary treatment step. The final part of the review provides an assessment of the environmental risk posed by their presence in the secondary effluent by means of the risk quotient that is the ratio between the average pharmaceutical concentration measured in the secondary effluent and the predicted no-effect concentration. Finally, mass load rankings of the compounds under review are compared with those based on their risk level. This analysis shows that the highest amounts discharged through secondary effluent pertain to one antihypertensive, and several beta-blockers and analgesics/anti-inflammatories, while the highest risk is posed by antibiotics and several psychiatric drugs and analgesics/anti-inflammatories. These results are reported with a view to aiding scientists and administrators in planning measures aiming to reduce the impact of treated urban wastewater discharge into surface water bodies.

The aim of this study was to assess the effect of several operational variables on both biological and separation process performance in a submerged anaerobic membrane bioreactor pilot plant that treats urban wastewater. The pilot plant is equipped with two industrial hollow-fibre ultrafiltration membrane modules (PURON¿ Koch Membrane Systems, 30m 2 of filtration surface each). It was operated under mesophilic conditions (at 33°C), 70days of SRT, and variable HRT ranging from 20 to 6h. The effects of the influent COD/SO 4-S ratio (ranging from 2 to 12) and the MLTS concentration (ranging from 6 to 22gL -1) were also analysed. The main performance results were about 87% of COD removal, effluent VFA below 20mgL -1 and biogas methane concentrations over 55% v/v. Methane yield was strongly affected by the influent COD/SO 4-S ratio. No irreversible fouling problems were detected, even for MLTS concentrations above 22gL -1. © 2011 Elsevier Ltd., This research work has been supported by the Spanish Research Foundation (CICYT Projects CTM2008-06809-C02-01 and CTM2008-06809-C02-02), which is gratefully acknowledged.

Nitrogen removal and transformations were studied in two pilot-scale combinations of a special configuration of a subsurface wastewater infiltration system with vertical flow named symbiotic treatment®. Both pilot-scale combinations operated in parallel and each one consists of four stages in series, one of them with a vertical distribution of stages and the other one with a horizontal distribution. The main differences between them were the separation between stages (presence (the horizontal distribution)/absence (the vertical distribution) of filtration between steps), the hydraulic load (0.113 m3/m2 h and 0.082 m3/m2 h for the horizontal and the vertical distribution, respectively) and the depth of the soil filters (1 m each stage in the horizontal distribution whereas the depths in the vertical distribution ranges from 20 cm to 40 cm). Results of both configurations showed elevated dissolved oxygen concentration, and high removal of organic matter and total suspended solids (with mean removal values of 96% for COD for both plants and 90% and 98% for TSS for the vertical and the horizontal distribution, respectively). High total Kjeldahl nitrogen removals were obtained in both configurations (mean removals of 70% and 90% for the vertical and the horizontal distribution, respectively). Whereas the nitrification potential was higher in the configuration with horizontal distribution which includes pumping and filtering between stages and higher depth of the soil filters, both tested configurations showed promise for nitrification of wastewater, ammonia nitrogen was efficiently transformed to nitrate.

Seven mesocosm-scale constructed wetlands (CWs) of different configurations were operated outdoors for nine months to assess their ability to remove pharmaceuticals and personal care products (PPCPs) from urban wastewaters. CWs differed in some design parameters, namely the presence of plants, the species chosen (i.e., Typha angustifolia vs Phragmites australis), flow configuration (i.e., surface flow vs subsurface flow) and the presence of a gravel bed. A nearby conventional activated-sludge wastewater treatment plant (WWTP) fed with the same sewage was simultaneously monitored for comparison. The PPCPs ketoprofen, naproxen, ibuprofen, diclofenac, salicylic acid, carbamazepine, caffeine, galaxolide, tonalide and methyl dihydrojasmonate were monitored. The presence of plants favoured the removal of some PPCPs. The performance of the mesocosm studied was compound-dependant, soilless CWs showing the highest removal efficiency for ketoprofen, ibuprofen and carbamazepine, while free-water CWs with effluent leaving through the bottom of the tank performed well for the degradation of ketoprofen, salicylic acid, galaxolide and tonalide. Finally, subsurface horizontal flow CWs were efficient for the removal of caffeine. Significant linear correlations were observed between the removal of some PPCPs and temperature or redox potential. Hence, microbiological pathways appear to be the most probable degradation route for PPCPs in the CWs studied., This study was funded by the Spanish Ministry of Science and Innovation through projects CTM2008-06676-C05-04/TECNO and CTM2005-06457-C05-03 and by the Castilla y León Regional Government through the project LE009A07 and by the Castilla y León Regional Government through projects LE009A07 and LE037A10-2. One of us Ms. MH-V kindly acknowledges a FPU fellowship from the Spanish Ministry of Education; and Dr. VM acknowledges a Juan de la Cierva contract. We thank Juan Carlos Sánchez Sánchez for the maintenance of the systems. We thank Acciona Agua and Mancomunidad de Saneamiento de León y su Alfoz for their technical support.

In this study, nine metals (Al, Cd, Cr. Cu, Fe, Mn, Ni, Pb, and Zn) found in urban wastewater treatment plants (WTPs) in Bursa (Turkey) were monitored for 23 months in 2002 and 2007. Metal influent and effluent concentrations of wastewater stabilization ponds (WSPs) and the activated sludge process (ASP) measured via 24-h composite samples were used to determine removal efficiencies. Average influent concentrations ranged between 2 mu g/L (Cd) and 1975 mu g/L (Fe). In the stabilization ponds, the removal efficiency was 58% for Cr, while for Cd. Mn, and Pb, it was less than 20%. The activated sludge process yielded high removal efficiencies, ranging from 47% for Ni to 95% for Cr. The use of treated wastewaters for agricultural purposes was investigated, and it was determined that all metal concentrations met application limits, with the exception of Cr in wastewater stabilization pond effluent. Results showed that wastewater stabilization pond effluent reduced the receiving water quality with respect to Cr, Cu, Ni. and Pb. In addition, it was shown that effluent from the activated sludge process temporarily improved the receiving water quality with regard to the Cd, Cu, Mn, and Zn parameters. However, considering the periodic variations of the metals in both processes, water quality, and agricultural practices, it was determined that they should be monitored continuously. (C) 2009 Elsevier B.V. All rights reserved. BUSKİ

An ultra-high-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method has been developed for the simultaneous quantification and confirmation of 11 basic/acidic illicit drugs and relevant metabolites in surface and urban wastewater at ng/L levels. The sample pre-treatment consisted of a solid-phase extraction using Oasis MCX cartridges. Analyte deuterated compounds were used as surrogate internal standards (except for norbenzoylecgonine and norcocaine) to compensate for possible errors resulting from matrix effects and those associated to the sample preparation procedure. After SPE enrichment, the selected drugs were separated within 6 min under UHPLC optimized conditions. To efficiently combine UHPLC with MS/MS, a fast-acquisition triple quadrupole mass analyzer (TQD from Waters) in positive-ion mode (ESI+) was used. The excellent selectivity and sensitivity of the TQD analyzer in selected reaction monitoring mode allowed quantification and reliable identification at the LOQ levels. Satisfactory recoveries (70-120%) and precision (RSD < 20%) were obtained for most compounds in different types of water samples, spiked at two concentration levels [limit of quantification (LOQ) and 10LOQ]. Thus, surface water was spiked at 30 ng/L and 300 ng/L (amphetamine and amphetamine-like stimulants), 10 ng/L and 100 ng/L (cocaine and its metabolites), 300 ng/L and 3000 ng/L (tetrahydrocannabinol-COOH). Recovery experiments in effluent and influent wastewater were performed at spiking levels of three and fifteen times higher than the levels spiked in surface water, respectively. The validated method was applied to urban wastewater samples (influent and effluent). The acquisition of three selected reaction monitoring transitions per analyte allowed positive findings to be confirmed by accomplishment of ion ratios between the quantification transition and two additional specific confirmation transitions. In general, drug consumption increased in the weekends and during an important musical event. The highest concentration levels were 27.5 μg/L and 10.5 μg/L, which corresponded to 3,4-methylenedioxymethamphetamine (MDMA, or ecstasy) and to benzoylecgonine (a cocaine metabolite), respectively. The wastewater treatment plants showed good removal efficiency (>99%) for low levels of illicit drugs in water, but some difficulties were observed when high drug levels were present in wastewaters. © 2009 Elsevier B.V. All rights reserved.

Chemically assisted primary sedimentation (CAPS) or chemically enhanced primary treatment (CEPT) consists of adding chemicals in order to increase the coagulation, flocculation and sedimentation of raw wastewater. Over the last twenty years, the use of CAPS has increased due to the development of better coagulants and flocculation enhancers, stricter standards as well as the need for low-energy treatment technologies, especially in developing countries. This paper defines a very simple multi-criteria procedure to be used in order to select the best combination of coagulant and dose when using jar tests. It is based on the adoption of the following 5 criteria: COD percentage removal, sludge volume after 2 h, coagulant dose, coagulant cost, pH percentage variation. The mathematical affordability of the procedure was tested by comparing it with the well known analytic hierarchy process.

The potential value of zeolitic materials (ZM) obtained from a hazardous waste, such as coal fly ash, for the retention of NH4 + present in liquid effluents from a Sewage Treatment Plant (STP) is studied. A wastewater sample was taken from an STP in Zaragoza (Spain) after conventional treatment at the Plant. The water was treated with different amounts of three ZM: NaP1 zeolite, K-F zeolite and K-Chabazite/KPhillipsite zeolites all of them in powdered and granulated state. The wastewater was treated by two kinds of processes: continuous stirring batch experiments with powdered ZM, and fixed packed bed of granulated ZM in a column. The powdered materials reduced about 80% of NH4 + fromwastewater, even in the presence of Ca2+, which competes with NH4 + for the cation exchange sites in zeolites. Around 70% of NH4 + reduction was achieved with granulated materials. In both cases, moderate ZM/wastewater ratios had to be used to achieve those results, with K-zeolites slightly less effective in NH4 + retention., The present studywas financed by the Spanish “PlanNacional de I+D+I (2000–2003)” project PPQ2001-2359-C02-01, “Plan Nacional de I+D+I (2004–2007)” project CTM2004-04252-C02-00 and it has been supported also with funds from ERDF. We would like to express our gratitude to the technical staff at “La Almozara” Sewage Treatment Plant, Zaragoza (Spain) for their help in obtaining wastewater sample.