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Graphical abstract Highlights • The influence of water matrix on the efficiency of AOTs is overviewed. • Photolysis, photocatalysis, UV/H 2 O 2 -, Fenton-, and O 3 -based processes are reviewed. • Dissolved organic matter and inorganics can act as inhibitors and/or promoters. • The effect results from the interplay of the co-existing substances. • The knowledge on the role of matrix constituents is crucial for installation of AOTs. Abstract Micropollutants (MPs) in the aquatic compartments are originated from many sources and particularly from the effluents of urban wastewater treatment plants (UWWTPs). Advanced oxidation technologies (AOTs) usually applied after biological processes, have recently emerged as effective tertiary treatments for the removal of MPs, but the oxidation rates of the single compounds may be largely affected by the constituent species of the water matrix. These species include dissolved organic matter and inorganic species (e.g., carbonate, bicarbonate, nitrite, sulphate, chloride). This review analyses the impact of such substances on common AOTs including photolysis, UV/H 2 O 2 , Fenton, photocatalysis, and ozone-based processes. The degradation efficiency of single MPs by AOTs results from the combined impact of the water matrix constituents, which can have neutral, inhibiting or promoting effect, depending on the process and the mechanism by which these water components react. Organic species can be either inhibitors (by light attenuation; scavenging effects; or adsorption to catalyst) or promoters (by originating reactive oxygen species (ROS) which enhance indirect photolysis; or by regenerating the catalyst). Inorganic species can also be either inhibitors (by scavenging effects; formation of radicals less active than hydroxyl radicals; iron complexation; adsorption to catalyst or decrease of its effective surface area) or promoters (e.g., nitrate ions by formation of ROS; iron ions as additional source of catalyst). The available data reviewed here is limited and the role and mechanisms of individual water components are still not completely understood. Further studies are needed to elucidate the wide spectrum of reactions occurring in complex wastewaters and to increase the adoption of AOTs in UWWTPs. [ABSTRACT FROM AUTHOR]

Abstract The occurrence of micropollutants in the environment is a matter of high concern. Some regulations have been published in the last years and a Watch List of contaminants of emerging concern (CECs) for European Union monitoring of surface water was launched in the Decision 2015/495, including three estrogens (estrone, E1; 17-β-estradiol, E2; and 17-α-ethinylestradiol, EE2), four pharmaceuticals (diclofenac and the macrolide antibiotics azithromycin, clarithromycin and erythromycin), an anti-oxidant (2,6-ditert-butyl-4-methylphenol, BHT), an UV filter (2-ethylhexyl 4-methoxycinnamate, EHMC), some pesticides (methiocarb and the neonicotinoids imidacloprid, thiacloprid, thiamethoxam, clothianidin and acetamiprid) and two herbicides (oxadiazon and triallate). This study provides the first spatial and seasonal monitoring campaign in the Ave and the Sousa Rivers for the all set of the 17 Watch List CECs (not reported yet for any country), in order to assess their occurrence, distribution, frequency and risk assessment. It also highlights the need of extend the study to other regions and environmental matrices to investigate the occurrence and possible sources of contamination of CECs, aiming to give insights for decision makers to define mitigation strategies for a more sustainable water policy. Graphical abstract Unlabelled Image Highlights • EU Watch List of CECs monitored in the Ave and the Sousa Rivers. • Spatiotemporal monitoring of 2 rivers in 4 seasons: 13 CECs found of a total of 17. • The most frequent CECs were diclofenac, azithromycin and EHMC. • The highest concentrations were verified for diclofenac, EHMC and imidacloprid. • The monitoring of these CECs must be extended to other EU sites. [ABSTRACT FROM AUTHOR]

Abstract The presence of organic micropollutants (MPs) in the aquatic environment is strongly related to their difficult elimination by conventional water and wastewater treatment processes. Therefore, alternative treatment technologies are required to overcome this problem. In this domain, constructed wetlands (CWs) have gained increasing attention in the last years, mainly due to the low-cost, simple operation/maintenance and environmental friendliness of these systems. However, studies on the application of CWs to remove MPs from freshwater aquaculture effluents are still scarce. In this work, planted (Phragmites australis) vertical subsurface flow CWs, at microcosm scale, were investigated for the removal of MPs found in non-spiked freshwater aquaculture effluents, namely atrazine, isoproturon, perfluorooctanesulfonic acid (PFOS), clarithromycin, erythromycin, fluoxetine, norfluoxetine, and 2-ethylhexyl-4-methoxycinnamate (EHMC). A wider multi-component set of 36 MPs was also studied by adding these MPs at 100 ng L−1 to the same matrix (alachlor, atrazine, chlorfenvinphos, isoproturon, PFOS, azithromycin, clarithromycin, erythromycin, diclofenac, methiocarb, acetamiprid, clothianidin, thiacloprid, thiamethoxam, EHMC, simazine, atorvastatin, bezafibrate, carbamazepine, cephalexin, ceftiofur, citalopram, clindamycin, clofibric acid, diphenhydramine, enrofloxacin, fluoxetine, ketoprofen, metoprolol, norfluoxetine, ofloxacin, propranolol, tramadol, trimethoprim, venlafaxine, and warfarin). High weekly removal efficiencies (>87%) were observed for all MPs in both non-spiked and spiked experiments, with the exception of EHMC (removal rates between 0 and 86%). These results emphasize the potential of CWs to remove MPs from freshwater aquaculture effluents, but also the need to enhance the performance of these systems for the elimination of some recalcitrant MPs, such as EHMC, which was found at high concentrations in the studied effluents. Graphical abstract Unlabelled Image Highlights • Constructed wetland microcosms studied for the removal of organic micropollutants. • Spiked (36 micropollutants) and non-spiked aquaculture effluents were investigated. • Most micropollutants found in effluents were removed to below the detection limit. • Weekly removal efficiencies were higher than 87% for most spiked micropollutants. • The UV filter EHMC was the only recalcitrant micropollutant. [ABSTRACT FROM AUTHOR]

Abstract The European Union (EU) has recommended the monitoring of specific priority substances (PSs, Directive 2013/39) and some contaminants of emerging concern (CECs, Decision 2015/495) in surface waterbodies. The present study provides spatial distributions and temporal variations of a wide range of multi-class PSs and CECs in four stressed rivers in Portugal (Ave, Leça, Antuã, and Cértima). Thirteen micropollutants were found in all four rivers, including the priority pesticide isoproturon (up to 92 ng L−1), various pharmaceuticals (up to 396 ng L−1), and the UV-filter 2-ethyl-hexyl-4-methoxycinnamate (EHMC, up to 562 ng L−1) identified in Decision 2015/495. The industrial priority compound perfluorooctanesulfonic acid (PFOS) was found in three rivers (Antuã, Cértima, and Leça) below the method quantification limit, together with four pharmaceuticals not included in these EU guidelines. The already banned priority pesticide atrazine was detected in Ave, Antuã, and Leça (up to 41 ng L−1) and simazine in Cértima and Leça (up to 26 ng L−1). Acetamiprid and imidacloprid (included in Decision 2015/495) were only detected during the dry season in the Ave. Leça river was selected as a waterbody case study for assessment of fluorescence excitation-emission matrices (EEMs). These results matched the spatial distribution trend of micropollutants along the river, with stronger fluorescence response and higher concentrations being found downstream of industrial areas and urban wastewater treatment plants (WWTPs). Moreover, the fluorescence signature of surface water collected downstream of an urban WWTP aligned very well with that obtained for the respective WWTP effluent. Thus, actions are needed to preserve a good environmental status of these stressed European waterbodies. Graphical abstract Unlabelled Image Highlights • Spatial and seasonal variations of multi-class micropollutants were studied. • Four stressed rivers in Portugal were monitored in dry and wet seasons. • Ketoprofen, tramadol, enrofloxacin and thiacloprid were measured at highest levels. • The fluorescence EEMs of surface water matched the distribution of micropollutants. • Correlation of fluorescence signatures found for azithromycin, carbamazepine, EHMC. [ABSTRACT FROM AUTHOR]

The contamination of fresh water is a global concern. The huge impact of natural and anthropogenic organic substances that are constantly released into the environment, demands a better knowledge of the chemical status of Earth’s surface water. Water quality monitoring studies have been performed targeting different substances and/or classes of substances, in different regions of the world, using different types of sampling strategies and campaigns. This review article aims to gather the available dispersed information regarding the occurrence of priority substances (PSs) and contaminants of emerging concern (CECs) that must be monitored in Europe in surface water, according to the European Union Directive 2013/39/EU and the Watch List of Decision 2015/495/EU, respectively. Other specific organic pollutants not considered in these EU documents as substances of high concern, but with reported elevated frequency of detection at high concentrations, are also discussed. The search comprised worldwide publications from 2012, considering at least one of the following criteria: 4 sampling campaigns per year, wet and dry seasons, temporal and/or spatial monitoring of surface (river, estuarine, lake and/or coastal waters) and ground waters. The highest concentrations were found for: (i) the PSs atrazine, alachlor, trifluralin, heptachlor, hexachlorocyclohexane, polycyclic aromatic hydrocarbons and di(2-ethylhexyl)phthalate; (ii) the CECs azithromycin, clarithromycin, erythromycin, diclofenac, 17α-ethinylestradiol, imidacloprid and 2-ethylhexyl 4-methoxycinnamate; and (iii) other unregulated organic compounds (caffeine, naproxen, metolachlor, estriol, dimethoate, terbuthylazine, acetaminophen, ibuprofen, trimethoprim, ciprofloxacin, ketoprofen, atenolol, Bisphenol A, metoprolol, carbofuran, malathion, sulfamethoxazole, carbamazepine and ofloxacin). Most frequent substances as well as those found at highest concentrations in different seasons and regions, together with available risk assessment data, may be useful to identify possible future PS candidates. [ABSTRACT FROM AUTHOR]

The fate and removal of organic micropollutants in the environment is a demanding issue evidenced by the recent European policy. This work presents an analytical method for the trace quantification of 37 micropollutants including Priority Substances (Directive 2013/39/EU), substances of the recent watch list (Decision 2015/495/EU) and contaminants of emerging concern: pesticides, multi-class pharmaceuticals and a metabolite, estrogens and one industrial compound. The analytical method was based on solid phase extraction (SPE) followed by ultra-high performance liquid chromatography with tandem mass spectrometry (UHPLC–MS/MS), using eco-friendly solvents (ethanol and ultrapure water) both in the SPE and UHPLC, according to green analytical chemistry principles. Briefly, Oasis ® HLB cartridges were used to preconcentrate 100 mL of water samples and the reconstituted extracts were analyzed with a Kinetex™ column under reversed mode, the linear ranges extended to 200 ng L −1 ( R 2 > 0.99) for all the analytes. The method detection limits were between 0.04 and 2.26 ng L −1 and the method quantification limits were between 0.13 and 6.85 ng L −1 . The identity of the compounds was confirmed using two MS/MS transitions and its ion ratios, according to Decision 2002/657/EC. The validated method was applied to wastewater treatment plant samples, assessing the concentration of micropollutants after secondary biological and tertiary UV treatments. Lab-scale photolysis and ozonation experiments were also performed with the secondary effluents, with ozonation showing the best performance for the removal of most of the determined micropollutants. [ABSTRACT FROM AUTHOR]

• Ozonation investigated for the removal of antibiotics from aquaculture effluents. • Oxytetracycline, sulfamethoxazole and trimethoprim attacked by O 3 directly. • Florfenicol removed by hydroxyl radicals (HO•) only. • Sulfadimethoxine degradation is significantly affected by the water matrix. • Toxicological evaluation did not show increase of water toxicity after ozonation. Antibiotics are often applied in aquaculture to prevent fish diseases. These substances can cause disturbances on receiving waters, when not properly eliminated from the aquaculture effluents. In this work, ozone (O 3) was investigated as a possible oxidizing agent to remove fishery antibiotics from aquaculture effluents: florfenicol (FF), oxytetracycline (OTC), sulfadimethoxine (SDM), sulfamethoxazole (SMX), and trimethoprim (TMP). Batch experiments were performed using ultrapure water and aquaculture effluents spiked with a mixture of target antibiotics at relatively high concentrations (10 mg L-1 each). OTC, SMX and TMP were fully removed (< 30 min) regardless of the tested conditions, mainly by O 3 direct attack. In contrast, FF was partially removed in 30 min (∼ 10 and 60%, in aquaculture effluents and ultrapure water, respectively), but only in the presence of hydroxyl radicals (HO•), the FF concentrations reaching levels below the detection limits in ultrapure water after 60 min. In the case of SDM, its degradation was highly influenced by the selected water matrix, but with removals always higher than 68%. In continuous-flow experiments applying more environmentally relevant antibiotic concentrations (100 ng L-1 each) and low O 3 doses (1.5 mg L−1), ozonation highly removed (> 98%) all tested antibiotics from aquaculture effluents with a hydraulic retention time (HRT) of 10 min, except FF (68%). Although by-products were detected in treated samples, zebrafish (Danio rerio) embryotoxicity tests did not show a toxicity increase by applying this ozonation treatment. Ozonation is thus a possible solution to remove antibiotics from aquaculture effluents. Still, full-scale studies in aquaculture farms are needed, and generation of HO• may be favoured to readily oxidize the FF antibiotic. [Display omitted] [ABSTRACT FROM AUTHOR]

This review aims to present the issues associated to enantioseparation of chiral pharmaceuticals in biological and environmental matrices using chiral stationary phases (CSP). Thus, it related some enantioselective methods in liquid chromatography (LC) and compares the importance given to chiral separation in biomedical and environmental fields. For that the most used CSP, the enantioselective chromatographic methods, their advantages and drawbacks were swiftly revised and compared. The recent advances and the limitations of chiral analytical methods in LC were also discussed. [ABSTRACT FROM AUTHOR]

Fluoxetine (FLX) is a chiral fluorinated pharmaceutical indicated mainly for the treatment of depression and is one of the most dispensed drugs in the world. There is clear evidence of environmental contamination with this drug and its active metabolite norfluoxetine (NFLX). In this study the enantioselective biodegradation of racemic FLX and of its enantiomers by Labrys portucalensis strain F11 was assessed. When 2 μM of racemic FLX was supplemented as sole carbon source, complete removal of both enantiomers, with stoichiometric liberation of fluoride, was achieved in 30 d. For racemic FLX concentration of 4 and 9 μM, partial degradation of the enantiomers was obtained. In the presence of acetate as an additional carbon source, at 4, 9 and 21 μM of racemic FLX and at 25 μM of racemic FLX, (S)-FLX or (R)-FLX, complete degradation of the two enantiomers occurred. At higher concentrations of 45 and 89 μM of racemic FLX, partial degradation was achieved. Preferential degradation of the (R)-enantiomer was observed in all experiments. To our knowledge, this is the first time that enantioselective biodegradation of FLX by a single bacterium is reported. [ABSTRACT FROM AUTHOR]

Highlights: [•] The multi-techniques analytical approach allowed the evaluation of the degradation of fluoroquinolones by a microbial consortium. [•] Fluoride ions released exposed the incomplete mineralization of the fluoroquinolones. [•] Metabolites were identified by LC–MS/MS and QqTOF MS. [•] New structures of the intermediates were proposed. [Copyright &y& Elsevier]

Highlights: [•] Enantioseparation of fluoxetine and norfluoxetine on a Chirobiotic V. [•] Enantioselective HPLC-FD method for quantification of fluoxetine and norfluoxetine. [•] FLX was degraded in wastewater effluent samples. [ABSTRACT FROM AUTHOR]

• Municipal wastewater (MWW) was treated by advanced oxidation technologies (AOTs). • Direct contact membrane distillation (DCMD) was investigated as post-treatment. • Ozonation was efficient to remove 12 micropollutants (MPs) determined in MWW. • UV/H 2 O 2 as pre-treatment minimized the flux decline. • Flux decline was strongly related to the DOC content of the DCMD feed. In this work, the combination of advanced oxidation technologies (AOTs) and direct contact membrane distillation (DCMD) was investigated for the treatment of municipal wastewater collected from the secondary clarifier of a municipal wastewater treatment plant (MWWTP). Average removal efficiencies of the 12 micropollutants present in the wastewater samples were higher than 95 % with ozonation (O 3) and photolytic ozonation (UV/O 3), whereas only near 50 % of removal efficiency was achieved with UV-peroxidation (UV/H 2 O 2). When the ozone-based processes were combined with DCMD, the concentration of these micropollutants were below the detection limits in the respective permeate, increasing the quality of the treated water. However, the permeate fluxes in DCMD were remarkably higher when the wastewater was pre-treated with UV/H 2 O 2 instead of O 3 , most probably due to the better disinfection achieved by UV/H 2 O 2. It was also confirmed that the dissolved organic carbon (DOC) of the wastewater strongly affects the permeate fluxes achieved by DCMD. In this regard, the combination of the oxidation and membrane separation processes is more appropriate for wastewaters with low DOC contents (< 15 mg L−1). [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Exfoliated graphitic carbon nitride (g-C 3 N 4) was synthesised and characterized. • The metal-free photocatalyst was studied under visible light. • Efficient removal of micropollutants from secondary urban wastewater was achieved. • g-C 3 N 4 was supported on glass rings to avoid its recovery from treated wastewater. Abstract Heterogeneous photocatalysis under visible light was employed for the degradation of organic micropollutants (MPs) found in the biologically treated effluents of an urban wastewater treatment plant (UWWTP). The irradiation source consisted in 4 light emitting diodes (LEDs) with a nominal power of 400–500 W m–2 at 417 nm. Metal-free exfoliated graphitic carbon nitride (gCN T), which was synthetized through a simple thermal treatment using dicyandiamide as precursor, was employed as photocatalyst. The gCN T material was characterized using different techniques: N 2 adsorption isotherms at 77 K, electron microscopy (scanning and transmission) and diffuse reflectance UV–Vis. The photocatalytic performance of the material was compared to the commercial TiO 2 -P25, confirming that gCN T led to a remarkable higher removal efficiency of the target MPs. Most of these MPs were removed in less than 10 min to levels below the limit of quantification (carbamazepine > isoproturon > clopidogrel > diclofenac > atenolol > bezafibrate > tramadol > venlafaxine > fluoxetine). Indirect photolysis, resulting from the secondary reactive oxidants generated during the irradiation of the aqueous matrix components, was found to partially contribute for the elimination of the occurring MPs. In addition, the gCN T photocatalyst was immobilized on glass rings for use under continuous mode operation, a minimum residence time of 25 min being required to attain significant removal efficiencies. Phytotoxicity experiments showed that heterogeneous photocatalysis did not enhance the toxicity of the wastewaters. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Antibiotics, bacteria and ARB removal in secondary treated urban wastewater. • Antibiotics are efficiently oxidized by TiO 2 -photocatalysis with UVA-LEDs. • Methanol has a scavenging effect on the removal of the antibiotics. • Efficient inactivation of cultivable bacteria including those antibiotic resistant. • Bacterial regrowth is observed after 3-days storage of treated wastewater. Abstract Secondary urban wastewater samples were spiked with azithromycin (AZT), trimethoprim (TMP), ofloxacin (OFL) and sulfamethoxazole (SMX) at 100 µg L−1 to investigate the efficiency of a TiO 2 -photocatalytic treatment using UVA-LEDs. Different operating parameters were studied, such as the irradiation conditions, catalyst load and the use of methanol as carrier solvent and radical scavenger. The most efficient conditions to treat spiked urban wastewater (4 LEDs symmetrically distributed and 1.00 g L−1 of catalyst) were also assessed on the removal of the antibiotics at real concentrations, as well as on the inactivation and regrowth of bacteria after 3-day storage (total and resistant heterotrophs, Escherichia coli and enterococci). Clindamycin (CLI) was targeted when SMX was not detected. One-hour treatment was enough to reduce the analysed antibiotics to values below the detection limits and to decrease the bacterial load by 2 log-units. Bacterial regrowth was observed for total heterotrophs, after the storage of photocatalytic treated wastewater, to values close to pre-treatment. However, the antibiotic resistance percentage of such stored wastewater was always similar or lower than that of secondary urban wastewater. Thus, the potential of this process as part of the tertiary treatment is demonstrated, but conditions must be adjusted to minimize microbial regrowth. [ABSTRACT FROM AUTHOR]

Degradation and mineralization of ibuprofen (IBU) were investigated using Ultraviolet (UV) Light Emitting Diodes (LEDs) in TiO 2 photocatalysis. Samples of ultrapure water (UP) and a secondary treated effluent of a municipal wastewater treatment plant (WWTP), both spiked with IBU, as well as a highly concentrated IBU (230 mg L −1 ) pharmaceutical industry wastewater (PIWW), were tested in the TiO 2 /UV-LED system. Three operating parameters, namely, pH, catalyst load and number of LEDs were optimized. The process efficiency was evaluated in terms of IBU removal using high performance liquid chromatography (HPLC) and ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Additionally, the mineralization was investigated by determining the dissolved organic carbon (DOC) content. The chemical structures of transformation products were proposed based on the data obtained using liquid chromatography with a high resolution mass spectrometer ion trap/time-of-flight (LC-MS-IT-TOF). A possible pathway of IBU degradation was accordingly suggested. Bioassays were performed using the marine bacterium Vibrio fischeri to evaluate the potential acute toxicity of original and treated wastewaters. TiO 2 heterogeneous photocatalysis was efficient to remove IBU from UP and from PIWW, and less efficient in treating the wastewater from the municipal WWTP. The acute toxicity decreased by ca. 40% after treatment, regardless of the studied matrix. [ABSTRACT FROM AUTHOR]

The decoration of titanium (Ti) implant surfaces with TiO 2 nanotubes has emerged as a promising strategy to improve osseointegration and avoid infection. Nevertheless, it has been reported that nanotubular films are prone to peeling off from the Ti substrate due to the poor interfacial adhesion. The knowledge on the interfacial properties of such interface, although not well explored, is crucial for understanding the mechanisms behind the poor adhesion problem of these films and to further achieve an easy and effective solution to solve it. This paper is focused on the bio-functionalization of TiO 2 nanotubular films with zinc (Zn) as an antimicrobial and bone healing agent, together with two major components of bone matrix, namely calcium (Ca) and phosphorous (P). The main aim is, for the first time, the thorough characterization of the interface between TiO 2 nanotubes and the Ti substrate, along with the better understanding of the bio-functionalization mechanisms of TiO 2 nanotubes and their influence on the interfacial features of the films. TiO 2 nanotubes were successfully synthesized by two-step anodization and their bio-functionalization with Ca, P and Zn was achieved by reverse polarization anodization treatments. The in-depth characterization of the morphological and chemical features of TiO 2 nanotubes was carried out along their length by scanning transmission electron microscopy (STEM) and energy dispersive X-ray spectroscopy (EDS), before and after bio-functionalization treatments. STEM images showed that the interface between conventional TiO 2 nanotubes and Ti is non-continuous due to the existence of a hollow space. However, bio-functionalized TiO 2 nanotubes evidenced an interface with different features, due to the formation of an interfacial oxide film as a consequence of anodization, with a thickness comprised between 230 and 250 nm. The results presented in this work may inspire the emergence of novel surface treatment strategies seeking the long-term performance of metallic-modified osseointegrated implants. [ABSTRACT FROM AUTHOR]

It has been shown that the synthesis of TiO 2 nanotubes by anodization provides outstanding properties to Ti surfaces intended for dental and orthopedic implants applications. Beyond the very well-known potential of these surfaces to improve osseointegration and avoid infection, the knowledge on the adhesion and degradation behavior of TiO 2 nanotubes under the simultaneous action of wear and corrosion is still poorly understood and these are issues of tremendous importance. The main aim of this work is to investigate, for the first time, the tribo-electrochemical degradation behavior of Ti surfaces decorated with TiO 2 nanotubes before and after bio-functionalization treatments. Well-aligned TiO 2 nanotubes (NTs) were produced containing elements natively present in bone such as calcium (Ca) and phosphorous (P), in addition of zinc (Zn) as an antimicrobial agent and stimulator of bone formation. The synthesis of Ca/P/Zn-doped nanotubes (NT-Ca/P/Zn) was achieved by reverse polarization and anodization treatments applied to conventional TiO 2 nanotubes grown by two-step anodization. The nanotube surfaces were analyzed by scanning electron microscopy (SEM) while dark-field scanning transmission electron microscopy (STEM-DF) was used to characterize the Ti/TiO 2 nanotubular films interfaces. Tribo-electrochemical tests were conducted under reciprocating sliding conditions in artificial saliva. The open circuit potential (OCP) was monitored before, during and after sliding tests, and the coefficient of friction (COF) values were registered during rubbing action. The wear tracks resulting from sliding tests were characterized by SEM and wear volume measurements were carried out by 2D profilometry. The results show that the tribo-electrochemical behavior of TiO 2 nanotubes was significantly improved after bio-functionalization treatments. The higher electrochemical stability and lower mechanical degradation of these films was correlated with their improved adhesion strength to Ti substrate, which is granted by the nano-thick oxide film formed at the interface region, during bio-functionalization processes. A first insight on the degradation mechanisms taking place during tribo-electrochemical action is proposed. The outcomes of this study may contribute in a great extent for the development of new implant surfaces with improved biomechanical stability and thus contribute for the long term success of dental implants. [ABSTRACT FROM AUTHOR]

An aerobic granular sludge-sequencing batch reactor (AGS-SBR) was fed for 28-days with a simulated wastewater containing a mixture of chiral pharmaceuticals (CPs) (alprenolol, bisoprolol, metoprolol, propranolol, venlafaxine, salbutamol, fluoxetine and norfluoxetine), each at 1.3 μg L −1 . AGS-SBR exhibited the highest removal efficiency for norfluoxetine, with preferential removal of the ( R )-enantiomer indicating that biological-mediated processes occurred. For all other CPs, removal was non-enantioselective, occurring through biosorption onto AGS. A gradual decline of CPs removal was observed, probably related to the decrease of AGS adsorption capacity. Moreover, chemical oxygen demand (COD) content in the bulk liquid after anaerobic feeding increased, and P-release dropped, probably because the polyphosphate-accumulating organism's activity was affected. Nitrification was also affected as indicated by the ammonium effluent concentration increase. Moreover, CPs exposure promoted AGS disintegration, with decreasing granule size. After stopping CPs feeding, the AGS started to recover its compact structure, and the system returned its normal performance concerning COD- and P-removal. N-removal seemed to be a more sensitive process, as while the ammonium levels were fully restored at the end of operation, nitrite reduction was only partially restored. Results provide useful information on AGS performance during the treatment of wastewater containing pharmaceuticals, a frequent scenario in WWTP. [ABSTRACT FROM AUTHOR]

Although there are no legal discharge limits for micropollutants into the environment, some regulations have been published in the last few years. Recently, a watch list of substances for European Union-wide monitoring was reported in the Decision 2015/495/EU of 20 March 2015. Besides the substances previously recommended to be included by the Directive 39/2013/EU, namely two pharmaceuticals (diclofenac and the synthetic hormone 17-alpha-ethinylestradiol (EE2)) and a natural hormone (17-beta-estradiol (E2)), the first watch list of 10 substances/groups of substances also refers three macrolide antibiotics (azithromycin, clarithromycin and erythromycin), other natural hormone (estrone (E1)), some pesticides (methiocarb, oxadiazon, imidacloprid, thiacloprid, thiamethoxam, clothianidin, acetamiprid and triallate), a UV filter (2-ethylhexyl-4-methoxycinnamate) and an antioxidant (2,6-di-tert-butyl-4-methylphenol) commonly used as food additive. Since little is known about the removal of most of the substances included in the Decision 2015/495/EU, particularly regarding realistic concentrations in aqueous environmental samples, this review aims to: (i) overview the European policy in the water field; (ii) briefly describe the most commonly used conventional and advanced treatment processes to remove micropollutants; (iii) summarize the relevant data published in the last decade, regarding occurrence and removal in aqueous matrices of the 10 substances/groups of substances that were recently included in the first watch list for European Union monitoring (Decision 2015/495/EU); and (iv) highlight the lack of reports concerning some substances of the watch list, the study of un-spiked aquatic matrices and the assessment of transformation by-products. [ABSTRACT FROM AUTHOR]

The degradation of two organic pollutants (amoxicillin and diclofenac) in 0.1 mM aqueous solutions was studied by using advanced oxidation processes, namely ozonation, photolysis, photolytic ozonation, photocatalysis and photocatalytic ozonation. Diclofenac was degraded quickly under direct photolysis by artificial light (medium-pressure vapor arc, λ exc > 300 nm), while amoxicillin remained very stable. In the presence of ozone, regardless of the type of process, complete degradation of both organic pollutants was observed in less than 20 min. Photolysis or ozonation on their own led to modest values of total organic carbon (TOC) removal (<6% or 41%, respectively in 180 min), while for photocatalysis (no ozone present) a significant fraction of nonoxidizable compounds remained in the treated water (∼15% after 180 min). In the case of photolytic ozonation, the kinetics of TOC removal was slow. In contrast, a relatively fast and complete mineralization of amoxicillin and diclofenac (30 and 120 min, respectively) was achieved when applying the photocatalytic ozonation process. The absence of toxicity of the treated waters was confirmed by growth inhibition assays using two different microorganisms, Escherichia coli and Staphylococcus aureus . Photocatalytic ozonation was also applied to an urban wastewater spiked with both amoxicillin and diclofenac. The parent pollutants were easily oxidized, but the TOC removal was only as much as 68%, mainly due to the persistent presence of oxamic acid in the treated sample. The same treatment allowed the effective degradation of a wide group of micropollutants (pesticides, pharmaceuticals, hormones and an industrial compound) detected in non-spiked urban wastewater. [ABSTRACT FROM AUTHOR]

The viscoelastic properties of vertebrate connective tissues rarely undergo significant changes within physiological timescales, the only major exception being the reversible destiffening of the mammalian uterine cervix at the end of pregnancy. In contrast to this, the connective tissues of echinoderms (sea urchins, starfish, sea cucumbers, etc.) can switch reversibly between stiff and compliant conditions in timescales of around a second to minutes. Elucidation of the molecular mechanism underlying such mutability has implications for the zoological, ecological and evolutionary field. Important information could also arise for veterinary and biomedical sciences, particularly regarding the pathological plasticization or stiffening of connective tissue structures. In the present investigation we analyzed aspects of the ultrastructure and biochemistry in two representative models, the compass depressor ligament and the peristomial membrane of the edible sea urchin Paracentrotus lividus , compared in three different mechanical states. The results provide further evidence that the mechanical adaptability of echinoderm connective tissues does not necessarily imply changes in the collagen fibrils themselves. The higher glycosaminoglycan (GAG) content registered in the peristomial membrane with respect to the compass depressor ligament suggests a diverse role of these molecules in the two mutable collagenous tissues. The possible involvement of GAG in the mutability phenomenon will need further clarification. During the shift from a compliant to a standard condition, significant changes in GAG content were detected only in the compass depressor ligament. Similarities in terms of ultrastructure (collagen fibrillar assembling) and biochemistry (two alpha chains) were found between the two models and mammalian collagen. Nevertheless, differences in collagen immunoreactivity, alpha chain migration on SDS-PAGE and BLAST alignment highlighted the uniqueness of sea urchin collagen with respect to mammalian collagen. [ABSTRACT FROM AUTHOR]

Fluoxetine (FLX) is a chiral fluorinated pharmaceutical mainly indicated for treatment of depression and is one of the most distributed drugs. There is a clear evidence of environmental contamination with this drug. Aerobic granular sludge sequencing batch reactors constitute a promising technology for wastewater treatment; however the removal of carbon and nutrients can be affected by micropollutants. In this study, the fate and effect of FLX on reactor performance and on microbial population were investigated. FLX adsorption/desorption to the aerobic granules was observed. FLX shock loads (≤4 μM) did not show a significant effect on the COD removal. Ammonium removal efficiency decreased in the beginning of first shock load, but after 20 days, ammonia oxidizing bacteria became adapted. The nitrite concentration in the effluent was practically null indicating that nitrite oxidizing bacteria was not inhibited, whereas, nitrate was accumulated in the effluent, indicating that denitrification was affected. Phosphate removal was affected at the beginning showing a gradual adaptation, and the effluent concentration was <0.04 mM after 70 days. A shift in microbial community occurred probably due to FLX exposure, which induced adaptation/restructuration of the microbial population. This contributed to the robustness of the reactor, which was able to adapt to the FLX load. [ABSTRACT FROM AUTHOR]

[Display omitted] • TiO 2 was grown and crystallized on polysulfone, PTFE and PVDF membranes. • Diclofenac and 17α-ethinylestradiol were removed by adsorption and photocatalysis. • 17α-ethinylestradiol was preferentially adsorbed regardless of the membrane tested. • TiO 2 -polysulfone was the most active membrane for the removal of both pollutants. • TiO 2 -PVDF presented the highest stability in consecutive reaction cycles. TiO 2 in situ growth on three commercial membranes (polysulfone – PS, polyvinylidene fluoride – PVDF and polytetrafluoroethylene – PTFE) and its hydrothermal post-crystallization to transform TiO 2 into a photocatalytically-active phase, were investigated under mild synthesis conditions to preserve the textural properties of the supports. The membranes were successfully prepared and characterized by scanning electron microscopy, thermogravimetry analysis, N 2 physisorption, X-ray diffraction, and water contact angle measurements, among other techniques. Membrane supports with a more opened porosity and high hydrophilicity allowed to enhance the content and distribution of the anatase TiO 2 nanoparticles on the membrane surface. The efficiency and the permeate flux of the developed membranes were investigated to simultaneously remove diclofenac (DCF) and 17α-ethinylestradiol (EE2) from water by adsorption and UV–LED (light-emitting diode) photocatalysis under continuous recirculating mode. All TiO 2 membranes achieved removal efficiencies above 90% for both contaminants, EE2 being always preferentially adsorbed over DCF due to electrostatic repulsions between the DCF molecules and the surface of these membranes. The permeate flux of TiO 2 membranes was enhanced after UV-LED exposure as a consequence of the degradation of the contaminants adsorbed on the membrane surface during the dark phase. Moreover, the stability of TiO 2 nanoparticles on these membranes was studied by static tests under sonication and several consecutive reaction cycles. The TiO 2 membrane prepared with PVDF was the most stable, also presenting a high photocatalytic activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • DEP exposure impairs C. elegans behaviour: Reduced speed and swimming activity. • DEP-treated worms manifest ∼50 % degeneration in glutamatergic neurons. • After exposure, ∼16 % of CEP dopaminergic neurons exhibit structural deformities. • In silico docking unveil DEP's strong binding affinity to glutamatergic transporter. • DEP induces developmental delays and antioxidant enzyme (sod-3 & gst-4) expression. The growing body of evidence links exposure to particulate matter pollutants with an increased risk of neurodegenerative diseases. In the present study, we investigated whether diesel exhaust particles can induce neurobehavioral alterations associated with neurodegenerative effects on glutamatergic and dopaminergic neurons in Caenorhabditis elegans (C. elegans). Exposure to DEP at concentrations of 0.167 µg/cm2 and 1.67 µg/cm2 resulted in significant developmental delays and altered locomotion behaviour. These effects were accompanied by discernible alterations in the expressions of antioxidant genes sod-3 and gst-4 observed in transgenic strains. Behaviour analysis demonstrated a significant reduction in average speed (p < 0.001), altered paths, and decreased swimming activities (p < 0.01), particularly at mid and high doses. Subsequent assessment of neurodegeneration markers in glutamatergic (DA1240) and dopaminergic (BZ555) transgenic worms revealed notable glutamatergic neuron degeneration at 0.167 μg/cm2 (∼30 % moderate, ∼20 % advanced) and 1.67 μg/cm2 (∼28 % moderate, ∼24 % advanced, p < 0.0001), while dopaminergic neurons exhibited structural deformities (∼16 %) without significant degeneration in terms of blebs and breaks. Furthermore, in silico docking simulations suggest the presence of an antagonistic competitive inhibition induced by DEP in the evaluated neuro-targets, stronger for the glutamatergic transporter than for the dopaminergic receptor from the comparative binding affinity point of view. The results underscore DEP's distinctive neurodegenerative effects and suggest a link between locomotion defects and glutamatergic neurodegeneration in C. elegans , providing insights into environmental health risks assessment. [ABSTRACT FROM AUTHOR]

This is the report clarifying the orientation dependence of the wear behavior of Co–Cr–Mo alloy. The wear resistance of the Co–Cr–Mo alloy with face-centered cubic (fcc) structure was found to be higher on the planes in order of {110}, {001} and {111}. Quantitatively, the wear resistance on {110} is 1.5 times larger than that on {111}. The tendency showed in coincident with the orientation dependence of the surface hardness, as empirically suggested. However, we additionally found in the observation of the worn surface in the fcc-single crystals that the volume fraction of the hexagonal close-packed (hcp)-phase, which was formed as the strain-induced martensite during the wear test, was larger in the same order of the wear resistance. The variation in formation frequency of the hcp-phase during the wear test can be explained by focusing on the Schmid factor along the resultant direction of the applied stress and the friction stress. On the {111} surface where the Schmid factor for the strain-induced ε-martensite formation is small, homogeneous deformation microstructure covered by it was not developed even after long-time wear, resulting in lower wear resistance. The results strongly suggest that not only the hardness, but the distribution of the ε-martensite is important to control the wear behavior of the Co–Cr alloys with the extremely low stacking fault energy, and it can be achieved by the crystal orientation control in the γ-phase. [Display omitted] • Orientation dependence of the wear behavior of Co–Cr–Mo alloy was first clarified. • Quantitatively, the wear resistance on {110} is 1.5 times larger than that on {111}. • Strain-induced hcp-phase martensite formation behavior strongly affects the wear resistance. • Design of novel "single-crystalline implant" with much superior properties is expected. [ABSTRACT FROM AUTHOR]

• ACE synergy with CHT and ALG improved the system physical and biological features; • Swelling influences mainly the diameter of the samples reaching an increase of 134 %. • The films sustainably release ACE to the media acting as a drug delivery device. • ACE release into the site may reinforce the biological benefits of the systems. • ACE-based films have a non-cytotoxic profile and a positive biological performance The exploitation of natural origin macromolecules, as complex physical mixtures or drugs, increases in biomedical or tissue engineering (TE) solutions. Aloe Vera is a highly explored medicinal plant, from which the main polysaccharide is acemannan (ACE). The ACE combination with chitosan and alginate results in interactions that lead to mixed junction zones formation, predicting membrane functionality improvement. This work proposes the development and characterization of ACE-based blended films as a promising strategy to design a nature-derived bioactive platform. The results confirmed that stable complex polyelectrolyte structures were formed through different intermolecular interactions. The films present good dimensional stability, flexibility, an adequate swelling ability with mostly radial water uptake, and a sustainable ACE release to the medium. Positive biological performance of the ACE-based blended films with L929 cells also suggested that they can be applied in TE solutions, with the potential to act as bioactive topical platforms. [ABSTRACT FROM AUTHOR]

Cytostatics are highly toxic pharmaceuticals used in the treatment of cancer. These substances are partially excreted by the human body after administration. The inefficient removal of some cytostatics in urban wastewater treatment plants (WWTPs) allows them to reach surface waters and consequently the aquatic biota. However, information about their occurrence in urban wastewaters is available only for certain active ingredients. A liquid-liquid extraction method coupled to liquid-chromatography-tandem mass spectrometry analysis was developed, allowing the identification and quantification of 14 cytostatics in wastewater samples, avoiding the use of expensive sorbents. Moreover, satisfactory cytostatics' recoveries were achieved when the new method was applied to wastewaters from a Portuguese WWTP: average of (74 ± 21)% for the influents, (83 ± 22)% for secondary effluents, and (94 ± 24)% for tertiary effluents collected after UV treatment, except for imatinib. Doxorubicin, etoposide, megestrol and prednisone were completely eliminated in the first stage of the WWTP treatment (i.e. detected in the influents, but not in the effluents). Bicalutamide, capecitabine, cyclophosphamide, ifosfamide and mycophenolic acid were recalcitrant to UV radiation (i.e. detected in tertiary effluents), ifosfamide being the cytostatic most difficult to be removed (its concentration did not decrease from the entrance to the outlet of the WWTP). The risk at which aquatic organisms might be subjected, due to their exposure to cytostatics' concentrations 10-times lower than those found in the tertiary effluents, was estimated and it was verified that mycophenolic acid may represent a high risk. Although no risk was estimated for the other cytostatics, the risks associated to long-term and synergic exposure should not be ruled out. Unlabelled Image • Miniaturized liquid-liquid extraction is reliable and easy to implement. • 11 (out of 14) cytostatics were detected in wastewater treatment plant influents. • 6 (out of 11) cytostatics were completely degraded in the wastewater treatment plant. • 5 target cytostatics were recalcitrant to ultraviolet radiation • Mycophenolic acid is suspected to induce high risk in aquatic organisms. [ABSTRACT FROM AUTHOR]

Abstract Urban wastewater treatment plants (WWTPs) are among the main anthropogenic sources for the release of contaminants of emerging concern (CECs) into the environment, which can result in toxic and adverse effects on aquatic organisms and consequently on humans. Unfortunately, WWTPs are not designed to remove CECs and secondary (e.g., conventional activated sludge process, CAS) and tertiary (such as filtration and disinfection) treatments are not effective in the removal of most CECs entering WWTP. Accordingly, several advanced treatment methods have been investigated for the removal of CECs from wastewater, including consolidated (namely, activated carbon (AC) adsorption, ozonation and membranes) and new (such as advanced oxidation processes (AOPs)) processes/technologies. This review paper gathers the efforts of a group of international experts, members of the NEREUS COST Action ES1403 who for three years have been constructively discussing the state of the art and the best available technologies for the advanced treatment of urban wastewater. In particular, this work critically reviews the papers available in scientific literature on consolidated (ozonation, AC and membranes) and new advanced treatment methods (mainly AOPs) to analyse: (i) their efficiency in the removal of CECs from wastewater, (ii) advantages and drawbacks, (iii) possible obstacles to the application of AOPs, (iv) technological limitations and mid to long-term perspectives for the application of heterogeneous processes, and (v) a technical and economic comparison among the different processes/technologies. Graphical abstract Unlabelled Image Highlights • Adsorption, O 3 , NF and RO membranes filtration can effectively remove CECs. • (Solar driven) AOPs appear competitive for CECs removal from urban wastewater. • When applying O 3 or AOPs ecotoxicological studies should be performed. • Lack of comparative investigations between consolidated and new processes • Conclusive evaluation of the most suitable and cost effective solution/s not yet possible [ABSTRACT FROM AUTHOR]

The effect of different membranes, membrane modules, feed temperatures, flow rates and solute concentrations on the permeate flux and salt rejection in direct contact membrane distillation (DCMD) was first studied with synthetic seawater and compared to distilled water. After optimizing these operating conditions, DCMD was tested with real feed samples, namely river water (RW-R), seawater (SW-R), and a secondary effluent from a municipal wastewater treatment plant (MW-R). The permeate flux achieved with MW-R was significantly lower than those obtained with the other feed samples. Two membrane module configurations (H-cell and W-cell) were then studied using SW-S, spiking diphenhydramine (DP) as model organic pollutant in some experiments. The H-cell performed better in terms of permeate quality for the same volume of permeate collected. A long experiment (500 h) was conducted with SW-R employing a larger H-cell. Severe fouling was observed, but high rejections of ion species (>99%) were recorded together with complete rejections of pharmaceuticals (diclofenac, azithromycin, clarithromycin and erythromycin) detected in SW-R at 9.53–73.53 ng L −1 (detection limits <0.16 ng L −1 ). Colonies of Escherichia coli or enterococci were not detected in 100 mL of permeate (distillate) solution, complying with the European Directive for drinking water. [ABSTRACT FROM AUTHOR]

Photocatalytic ozonation was employed for the first time in continuous mode with TiO 2 -coated glass Raschig rings and light emitting diodes (LEDs) to treat urban wastewater as well as surface water collected from the supply area of a drinking water treatment plant (DWTP). Different levels of contamination and types of contaminants were considered in this work, including chemical priority substances (PSs) and contaminants of emerging concern (CECs), as well as potential human opportunistic antibiotic resistant bacteria and their genes (ARB&ARG). Photocatalytic ozonation was more effective than single ozonation (or even than TiO 2 catalytic ozonation) in the degradation of typical reaction by-products (such as oxalic acid), and more effective than photocatalysis to remove the parent micropollutants determined in urban wastewater. In fact, only fluoxetine, clarithromycin, erythromycin and 17-alpha-ethinylestradiol (EE2) were detected after photocatalytic ozonation, by using solid-phase extraction (SPE) pre-concentration and LC-MS/MS analysis. In surface water, this treatment allowed the removal of all determined micropollutants to levels below the limit of detection (0.01–0.20 ng L −1 ). The efficiency of this process was then assessed based on the capacity to remove different groups of cultivable microorganisms and housekeeping (16S rRNA) and antibiotic resistance or related genes ( intI1, blaTEM , qnrS , sul1 ). Photocatalytic ozonation was observed to efficiently remove microorganisms and ARGs. Although after storage total heterotrophic and ARB (to ciprofloxacin, gentamicin, meropenem), fungi, and the genes 16S rRNA and intI1 , increased to values close to the pre-treatment levels, the ARGs ( blaTEM , qnrS and sul1 ) were reduced to levels below/close to the quantification limit even after 3-days storage of treated surface water or wastewater. Yeast estrogen screen (YES), thiazolyl blue tetrazolium reduction (MTT) and lactate dehydrogenase (LDH) assays were also performed before and after photocatalytic ozonation to evaluate the potential estrogenic activity, the cellular metabolic activity and the cell viability. Compounds with estrogenic effects and significant differences concerning cell viability were not observed in any case. A slight cytotoxicity was only detected for Caco-2 and hCMEC/D3 cell lines after treatment of the urban wastewater, but not for L929 fibroblasts. [ABSTRACT FROM AUTHOR]

Direct photolysis and TiO 2 -photocatalytic degradation of naproxen (NPX) in aqueous solution were studied using a UV lamp and solar irradiation. The degradation of NPX was found to be in accordance with pseudo-first order kinetics, the photocatalytic process being more efficient than photolysis. The NPX removal by photolysis (pH initial 6.5) was 83% after 3 h, with 11% of chemical oxygen demand (COD) reduction, whereas the TiO 2 -UV process led to higher removals of both NPX (98%) and COD (25%). The apparent pseudo-first-order rate constant ( k app ) for NPX degradation by photolysis ranged from 0.0050 min −1 at pH 3.5 to 0.0095 min −1 at pH 6.5, while it was estimated to be 0.0063 min −1 under acidic conditions in photocatalysis, increasing by 4-fold at pH 6.5. Ultra High Performance Liquid chromatography (UHPLC) coupled with a triple quadrupole detector and also a hybrid mass spectrometer which combines the linear ion trap triple quadrupole (LTQ) and OrbiTrap mass analyser, were used to identify NPX degradation products. The main intermediates detected were 1-(6-methoxynaphtalene-2-yl) ethylhydroperoxide, 2-ethyl-6-methoxynaphthalene, 1-(6-methoxynaphtalen-2-yl) ethanol, 1-(6-methoxynaphtalen-2-yl) ethanone and malic acid. Solar photocatalysis of NPX showed COD removals of 33% and 65% after 3 and 4 h of treatment, respectively, and some reduction of acute toxicity, evaluated by the exposure of Eisenia andrei to OECD soils spiked with NPX-treated solutions. [ABSTRACT FROM AUTHOR]

• N-doped reduced graphene oxide was synthesized using melamine (M) as N source (rGO-M). • A rGO-M-PVDF composite membrane was prepared by including rGO-M in a PVDF matrix. • rGO-M-PVDF promoted the activation of persulfate in continuous mode. • Conversions of micropollutants in the range 54–91% were obtained. • rGO-M-PVDF showed resistance towards fouling phenomena. Metal-free carbon-based polymer nanocomposite membranes were employed for the first time for activated persulfate oxidation in continuous mode of operation. For that purpose, reduced graphene oxide doped with nitrogen by using melamine as source (rGO-M) was included as catalytic active phase in a poly(vinylidene fluoride) matrix (PVDF). The performance of the resulting composite membrane (rGO-M-PVDF) was compared against that obtained with supported membranes prepared by simple filtration of rGO-M into a PTFE substrate. The uniform distribution of rGO-M within both the surface pores and cross-sectional channels of the composite rGO-M-PVDF membrane (with a thickness of 292 ± 20 μm) was confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), while its main structural features were studied by X-ray diffraction (XRD) and Raman spectroscopy. The quite good performance of this composite membrane was demonstrated by the degradation of three fluoroquinolone antibiotics at ppb level in ultrapure water (100 μg L−1 each), leading to average pollutant mass removal rates in the range 2.05–2.73 mg m−2 h−1. Conversions of the pharmaceuticals in the range 54–91% were obtained even after 24 h of operation in full continuous mode. Persulfate conversion was confirmed and high resistance to fouling was observed with this novel catalytic membrane. Average pollutant mass removal rates in the range 0.34–0.77 mg m−2 h−1 were obtained in preliminary experiments performed with surface water instead of ultrapure water, highlighting the need for additional studies on both water matrix effects and process optimization. [ABSTRACT FROM AUTHOR]