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Antineoplastic drugs are pharmaceuticals that have been raising concerns among the scientific community due to: (i) their increasing prescription in the fight against the disease of the twentieth century (cancer); (ii) their recalcitrance to conventional wastewater treatments; (iii) their poor environmental biodegradability; and (iv) their potential risk to any eukaryotic organism. This emerges the urgency in finding solutions to mitigate the entrance and accumulation of these hazardous chemicals in the environment. Advanced oxidation processes (AOPs) have been taken into consideration to improve the degradation of antineoplastic drugs in wastewater treatment plants (WWTPs), but the formation of by-products that are more toxic or exhibit a different toxicity profile than the parent drug is frequently reported. This work evaluates the performance of a nanofiltration pilot unit, equipped with a Desal 5DK membrane, in the treatment of real WWTP effluents contaminated (without spiking) with eleven pharmaceuticals, five of which were never studied before. Average removals of 68 ± 23% were achieved for the eleven compounds, with decreasing risks from feed to permeate for aquatic organisms from receiving waterbodies (with the exception of cyclophosphamide, for which a high risk was estimated in the permeate). Aditionally, no significative impact on the growth and germination of three different seeds (Lepidium sativum, Sinapis alba, and Sorghum saccharatum) were determined for permeate matrix in comparison to the control. [Display omitted] • Up to 127 ± 20 ng/L (feed), 38 ± 2 ng/L (permeate) and 1512 ± 70 ng/L (retentate). • Average removals of 68 ± 23% were achieved for the eleven pharmaceuticals. • Risk to aquatic organisms was decreased after nanofiltration. • Permeate did not affect the germination/growth of plants compared to control. • Degradation post-treatments are recommended after the nanofiltration process. [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]

Silica@polymer spheres with a core@shell structure were synthesized and thermally annealed at 800 ºC to obtain silica@carbon spheres (SiO 2 @CSs). The silica core was removed by etching with NaOH, hollow carbon spheres (CSs) being obtained. The particle size of SiO 2 @CSs and CSs increased with the ethanol/water (E/W) volumetric ratio (2, 4.5, and 7) employed in the first synthesis step (i.e. , the Stöber's method to obtain silica particles). Moreover, the average diameter of the materials prepared with E/W ratio of 2 was affected by the etching of the SiO 2 core (from 168 to 109 nm), in contrast with those synthesized at higher E/W ratios of 4.5 and 7 (251–245 and 270–284 nm, respectively). The specific surface area (S BET) of the CSs ranged from 271 to 602 m2 g−1, which are more porous than SiO 2 @CSs (S BET in the range 115–144 m2 g−1). Adsorption kinetic and equilibrium studies were carried out with diclofenac and venlafaxine as model organic micropollutants (OMPs). Despite the silica removal was not effective for all the CSs (TGA residue ranging from 3 to 46 wt%), the kinetic studies and the ATR-FTIR spectra confirmed the positive effect of having a hollow core (i.e. , removing the silica core). Equilibrium studies demonstrated that CSs prepared with an E/W ratio of 7 were the best performing material when considering both OMPs. Moreover, these CSs performed well to remove a set of 24 OMPs from wastewater effluents and thus, they are an interesting option for water or wastewater treatment. [Display omitted] • Nanostructured hollow carbon spheres (CSs) with different sizes synthesized. • First study employing CSs for the adsorption of diclofenac and venlafaxine (VFX). • Beneficial role of the hollow core within the CSs was demonstrated. • Best performance in equilibrium tests with the CSs having larger particle size. • Highest VFX adsorption capacity (61.45 mg g-1) among reported carbon materials. [ABSTRACT FROM AUTHOR]

Ozone-based water treatments were investigated to simultaneously remove organic micropollutants (OMPs) and bacteria from surface water samples collected in a river reservoir supplying a drinking water treatment plant. Among the 21 environmentally relevant OMPs selected, 15 were detected at low (< 20) ng L−1 level. Surface water samples were then spiked with these 21 OMPs (100 ng L−1) and the ozone-based treatments were tested with excess of ozone and high hydraulic retention time (HRT: 41 min). Regardless of the treatment applied (O 3 , O 3 /UVA-LEDs, and O 3 /H 2 O 2), removal efficiencies higher than 85% were always obtained for 20 out of 21 OMPs (and lower than 50% for PFOS). Thus, single ozonation was considered the best treatment solution, being afterwards investigated in terms of water disinfection at milder operating conditions (3 mg O 3 L−1 and HRT: 10 min). Under these conditions, the removals of spiked OMPs were also higher than 85% (except for PFOS), whereas bacteria (i.e. , total heterotrophs at 37 and 22 °C, E. coli and enterococci) decreased to values lower than the permissible levels for drinking water, even upon storage for 3-days. However, lower ozone doses (1.5 mg O 3 L−1) could not prevent the regrowth of total heterotrophs incubated at 37 °C, which reached levels five times higher than those recommended. Because drinking water treatments should not only consider OMPs abatement but also microbial inactivation for long periods of time, the results herein obtained point out the importance of using ozone doses capable of accomplish both targets when using single ozonation. [Display omitted] • Ozone-based treatments investigated for surface water intended for consumption. • 20 out of 21 organic micropollutants were removed (>85%) by single ozonation. • PFOS removals were lower than 50% regardless of the treatment process tested. • The treated water had sufficient microbial quality for human consumption. • Ozone doses lower than 3 mg O 3 L−1 are not recommended due to bacteria regrowth. [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]