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1.
Environ Sci Pollut Res Int ; 31(5): 6782-6814, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38165540

RESUMO

This study presents a systematic review of the scientific and technological production related to the use of systems based on UV, H2O2, and Cl2 for the elimination of antibiotic-resistant bacteria (ARB) and genes associated with antibiotic resistance (ARGs). Using the Pro Know-C (Knowledge Development Process-Constructivist) methodology, a portfolio was created and analyzed that includes 19 articles and 18 patents published between 2011 and 2022. The results show a greater scientific-technological production in UV irradiation systems (8 articles and 5 patents) and the binary combination UV/H2O2 (9 articles and 4 patents). It was emphasized that UV irradiation alone focuses mainly on the removal of ARB, while the addition of H2O2 or Cl2, either individually or in binary combinations with UV, enhances the removal of ARB and ARG. The need for further research on the UV/H2O2/Cl2 system is emphasized, as gaps in the scientific-technological production of this system (0 articles and 2 patents), especially in its electrochemically assisted implementation, have been identified. Despite the gaps identified, there are promising prospects for the use of combined electrochemically assisted UV/H2O2/Cl2 disinfection systems. This is demonstrated by the effective removal of a wide range of contaminants, including ARB, fungi, and viruses, as well as microorganisms resistant to conventional disinfectants, while reducing the formation of toxic by-products.


Assuntos
Peróxido de Hidrogênio , Purificação da Água , Antagonistas de Receptores de Angiotensina , Purificação da Água/métodos , Cloro , Inibidores da Enzima Conversora de Angiotensina , Resistência Microbiana a Medicamentos/genética , Bactérias/genética , Desinfecção/métodos , Raios Ultravioleta
2.
Environ Sci Pollut Res Int ; 29(28): 42275-42289, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34993786

RESUMO

In this work, the use of natural organic wastes (orange and lemon peels) as sources of citric acid was evaluated along with the application of the photoelectro-Fenton (PEF) system under non-modified pH as a novel alternative to degrade a complex mixture of pharmaceuticals: sulfamethoxazole (SMX-7.90 × 10-5 mol/L) and trimethoprim (TMP-6.89 × 10-5 mol/L). The system was equipped with a carbon felt air diffusion cathode (GDE) and a Ti/IrO2 anode doped with SnO2 (DSA). A 3.6 × 10-5 mol/L solution of commercial citric acid was used as a reference. The pharmaceuticals' evolution in the mixture was followed by high-performance liquid chromatography (HPLC). The addition of natural products showed an efficient simultaneous degradation of the antibiotics (100% of SMX and TMP at 45 min and 90 min, respectively) similar to the performance produced by adding the commercial citric acid to the PEF system. Moreover, the addition of natural products allowed for an increment of biodegradability (100% removal of TOC by a modified Zahn Wellens test) and a decrease in ecotoxicity (0% in the bioassay with D. Magna) of the treated solutions. The antibacterial activity was eliminated after only 45 min of treatment, suggesting that the degradation by-products do not represent a significant risk to human health or the environment in general. Results suggest that, because of the efficient formation of Fe-citrate complexes, the PEF could be enhanced by the addition of natural organic wastes as a sustainable alternative ecological system for water contaminated pharmaceuticals. Additionally, the potential of reusing natural organic wastes has been exposed, contributing to an improved low-cost PEF by decreasing the environmental contamination produced by this type of waste.


Assuntos
Produtos Biológicos , Poluentes Químicos da Água , Antibacterianos , Ácido Cítrico , Eletrodos , Humanos , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Ferro/química , Oxirredução , Preparações Farmacêuticas , Sulfametoxazol , Trimetoprima , Poluentes Químicos da Água/química
3.
Sci Total Environ ; 772: 144890, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578165

RESUMO

In this work, the occurrences of bacteria families and relevant pharmaceuticals in municipal wastewater effluents from Bogotá (Colombia), and their treatment by the photo-electro-Fenton process were studied. Twenty-five representative pharmaceuticals (azithromycin, carbamazepine, ciprofloxacin, clarithromycin, diclofenac, enalapril, gabapentin, iopromide, metoprolol, sulfamethoxazole, trimethoprim, valsartan, clindamycin, erythromycin, levamisole, lincomycin, norfloxacin, oxolinic acid, phenazone, primidone, salbutamol, sulfadiazine, tetracycline, tramadol, and venlafaxine) were quantified in the effluent by LC-MS/MS analysis. Four of these target compounds (azithromycin, diclofenac, trimethoprim, norfloxacin) were found at concentrations that represent an environmental risk. In addition, several bacteria families related to water and foodborne diseases were identified in such effluents (e.g., Pseudomonadaceae, Campylobacteraceae, Aeromonadaceae, Enterobacteriaceae, and Bacteroidaceae), via shotgun-metagenomic technique. Then, a bench-scale photo-electro-Fenton (PEF) system equipped with a DSA anode (Ti/IrO2-SnO2) and a GDE cathode was applied to treat such effluents. After 60 min, this treatment led to a decrease in the ratio of the bacterial content in the original samples, ~150 thousand times, and a pondered removal of 66.12% for the pharmaceuticals. The study of the process pathways indicated that the bacteria and pharmaceuticals elimination mainly occurred through attacks of hydroxyl and chlorine radicals. Interestingly, in the case of pharmaceuticals, their environmental risk quotients were diminished after the PEF application. Furthermore, the prolonged action of this electrochemical process induced ~15% of mineralization and a significant reduction of the total DNA (removal >85%). Hence, the photo-electro-Fenton process showed to be a promising alternative to deal with municipal effluents for limiting the waterborne diseases, pollution by pharmaceuticals, and mobility/availability of genetic material coming from microorganisms.


Assuntos
Preparações Farmacêuticas , Poluentes Químicos da Água , Bactérias , Cromatografia Líquida , Colômbia , Humanos , Peróxido de Hidrogênio , Ferro , Oxirredução , Espectrometria de Massas em Tandem , Águas Residuárias , Poluentes Químicos da Água/análise
4.
Environ Sci Pollut Res Int ; 28(19): 23984-23994, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33405147

RESUMO

This work deals with the theoretical approach of biodegradability, lipophilicity, and physiological activity of VAL and four degradation products (DPs) detected after 20 min of the photo-electro-Fenton (PEF) process. The biodegradability calculation, taking into account the change in the theoretical oxygen demand, showed that the four DPs had a more negative value than VAL, indicating that they are more susceptible to oxidation. However, these results do not imply more accessible biotransformation pathways than VAL, as observed using the EAWAG-BBD program, through which neutral biotransformation pathway prediction for VAL and DPs was made. Subsequently, by calculating the theoretical lipophilicity of the molecules (log P), the theoretical toxicity of the DPs was proposed, where the DPs had log P values between 1 and 3, lower values than those of VAL (log P = 4), indicating that DPs could be less toxic than the original compound (VAL). Both results suggest that VAL degradation (by photo-electro-Fenton process proposed) yields a positive effect on the environment. Finally, when molecular dynamic simulations were carried out, it was observed that DP1, DP2, and DP3 maintained similar interactions to those of VAL with the binding site of the AT1R. DP4 did not show any interaction. These results indicated that, despite the presence of DPs, generated after 20 min of the treatment, they could not exert a physiological activity in any organism the same way that does VAL.


Assuntos
Peróxido de Hidrogênio , Poluentes Químicos da Água , Computadores , Ferro , Oxirredução , Receptor Tipo 1 de Angiotensina , Valsartana , Poluentes Químicos da Água/análise
5.
Chemosphere ; 270: 129491, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33429235

RESUMO

Degradation of two representative antihypertensives, losartan (LOS) and valsartan (VAL) in water by photo-electro-Fenton (PEF), using a BDD anode in presence of sulfate anion was evaluated. PEF showed a fast elimination of these pollutants (>95% at 30 and 60 min of treatment for LOS and VAL, respectively). The main elimination route was the attacks of radicals produced in the system, having pseudo-first-order rate constants of 0.154 and 0.054 min-1 for LOS and VAL, correspondingly. Theoretical analyses of atomic charges were performed to rationalize the antihypertensives reactivity toward the electrogenerated degrading agents. Afterwards, the primary transformation products were assessed. The transformation products revealed that the degrading species attack the biphenyl-tetrazole, imidazole, and alcohol moieties on LOS. Meanwhile, carboxylic and amide groups, plus the central nucleus, were modified on VAL. These moieties corresponded well with the electron-rich sites indicated by the theoretical calculations. Also, the PEF process removed between 33 and 38% of total organic carbon after 5 h of electrolysis. Finally, it was considered LOS treatment in presence of oxalic acid (a typical organic waste of pharmaceutical industry), in addition to the pollutant degradation in effluents from municipal sewage treatment plants by PEF at pH ∼5. Oxalic acid accelerated LOS degradation. Meanwhile, in the effluent, the process led to 64% of LOS removal after 120 min of treatment, indicating the high potentiality of PEF to degrade antihypertensives in water containing organic and inorganic substances.


Assuntos
Anti-Hipertensivos , Poluentes Químicos da Água , Bloqueadores do Receptor Tipo 1 de Angiotensina II , Eletrodos , Peróxido de Hidrogênio , Cinética , Oxirredução , Água
6.
Sci Total Environ ; 670: 623-632, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-30909040

RESUMO

This work presents the treatment of selected emerging concern pharmaceuticals in real hospital wastewater (HWW) from Tumaco-Colombia by combination of a biological system with a sonochemical process. Fifteen compounds, commonly present in HWW, were considered: acetaminophen, diclofenac, carbamazepine, venlafaxine, loratadine, ciprofloxacin, norfloxacin, valsartan, irbesartan, sulfamethoxazole, trimethoprim, clarithromycin, azithromycin, erythromycin and clindamycin. Initially, HWW was characterized in terms of global parameters and the pharmaceuticals content. HWW contained a moderate amount of organic matter (i.e., total organic carbon: 131.56 mg L-1 (C)) mainly associated to biodegradable components. However, the most of pharmaceuticals were found at levels upper than their predicted no effect concentration (PNEC). Then, a conventional biological treatment was applied to the HWW. After 36 h, such process mainly removed biodegradable substances, but had a limited action on the pharmaceuticals. The resultant biotreated water was submitted to the sonochemical process (375 kHz and 88 W L-1, 1.5 h), which due to its chemical (i.e., radical attacks) and physical (i.e., suspended solids disaggregation) effects induced a considerable pharmaceuticals degradation (pondered removal: 58.82%), demonstrating the complementarity of the proposed combination. Afterwards, Fe2+ (5 ppm) and UVC light (4 W) were added to the sonochemical system (generating sono-photo-Fenton process), which significantly increased up to 82.86% the pondered pharmaceuticals removal. Subsequently, to understand fundamental aspects of the pharmaceuticals degradations, a model compound (norfloxacin) in distilled water was treated by sonochemical system, sono-photo-Fenton process and their sub-systems (i.e., sono-Fenton and UVC alone). This allowed proving the hydroxyl radical action in sonochemical treatment, plus the contribution of Fenton reaction and direct photodegradation in the pharmaceuticals removal by sono-photo-Fenton. Finally, it was found that 91.13% of the initial pharmaceuticals load in HWW was removed by the biological/sono-photo-Fenton combination. The high pollutants abatement evidenced that this combination is a powerful alternative for removing pharmaceuticals from complex-matrix waters, such as raw HWW.


Assuntos
Hospitais , Preparações Farmacêuticas/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Biodegradação Ambiental , Colômbia , Peróxido de Hidrogênio , Radical Hidroxila , Ferro , Oxirredução , Sulfametoxazol , Águas Residuárias/química , Purificação da Água
7.
Water Res ; 154: 349-360, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30818100

RESUMO

The simultaneous degradation of seventeen emerging concern pollutants in effluent from the municipal wastewater treatment plant (MWTP) of Bogotá-Colombia was studied using high frequency ultrasound (375 kHz). The considered compounds in the effluent corresponded to pharmaceuticals (diclofenac, carbamazepine, venlafaxine, ciprofloxacin, norfloxacin, valsartan, losartan, irbesartan, sulfamethoxazole, clarithromycin, azithromycin, erythromycin, metronidazole, trimethoprim and clindamycin); cocaine and its major metabolite benzoylecgonine. Due to limitation of the MWTP for the pollutants elimination, ultrasound was applied to remove these compounds. Interestingly, ultrasonic physical action led to releasing of ciprofloxacin, norfloxacin, diclofenac and sulfamethoxazole from suspended solids, whereas the chemical effects induced degradation of the rest of compounds. For the latter ones, an interesting correlation between the sonodegradation and arithmetic multiplication between hydrophobicity and concentration of pollutants was established. Afterwards, the sonochemical process was complemented with ferrous ions (sono-Fenton), ferrous ions plus light (sono-photo-Fenton) or ferrous ions plus light in presence of oxalic acid (sono-photo-Fenton/oxalic acid). Additionally, to clarify fundamental aspects of the different systems, individual treatments in distilled water of a model pollutant (valsartan) were performed. The complemented processes significantly enhanced all compounds degradation, following the order: sono-photo-Fenton/oxalic acid > sono-photo-Fenton ∼ sono-Fenton > sonochemistry. The Fe2+ addition improved the pollutants elimination by generation of more hydroxyl radicals in the solution bulk. Meanwhile, oxalic acid avoided Fe3+ precipitation favoring the iron catalytic cycle. Thus, the work demonstrates the high potentiality of the sono-photo-Fenton/oxalic acid system for the pollutants elimination in real-world wastewater matrices.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Peróxido de Hidrogênio , Ferro , Oxirredução
8.
Environ Sci Pollut Res Int ; 26(5): 4426-4437, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29971747

RESUMO

In this work photo-electro-Fenton (PEF) processes using a dimensionally stable anode-gas diffusion electrode (DSA-GDE) system under light emission diodes (LED)-type radiation were used in the degradation of the angiotensin-II-receptor antagonists (ARA II), valsartan (VAL), and losartan (LOS), which are used in the treatment of hypertension diseases, and are considered among the emerging contaminants (ECs). Organic acids as citric, tartaric, and oxalic acids were used as complexing agents of iron ions in order to maintain the performance of the Fenton reaction at near-neutral pH value. The results show that at 3.42 mA/cm2 after 90 min of electro-Fenton (EF) treatment, degradation of 70% of VAL and 100% of LOS were observed. Total degradation of VAL and LOS was reached with a PEF process at the same time with mineralization of 30%. When citric and tartaric acids were used instead of oxalic acid, similar results were obtained, i.e., total degradation of both compounds, LOS and VAL, after 90 min of treatment. The degradation performance can be attributed to the increase of the initial dissolved iron in the system, facilitating the Fe3+/Fe2+ turnover in the catalytic photo-Fenton reaction and consequently, hydroxyl radical (•OH) production. In addition, the increased photo-activity of the complexes can be associated with their high capability to complex Fe3+ and to promote ligand-to-metal charge transfer, which is of key importance to feed Fe2+ to the Fenton process. The results show that the system evaluated was more efficient to eliminate sartan family compounds using LED lighting in comparison with traditional UV-A lamps used in this kind of work. Moreover, three transformation products of VAL degradation and two transformation products of LOS degradation were identified by high-resolution mass spectrometry (HRMS) using hybrid quadrupole-time-of-flight (QTOF) MS and, at the end of the PEF system, the several organic compounds accumulated and no mineralized were effectively treated in a subsequent aerobic biological system.


Assuntos
Eletrodos , Losartan/química , Valsartana/química , Poluentes Químicos da Água/química , Anti-Hipertensivos/química , Anti-Hipertensivos/metabolismo , Biodegradação Ambiental , Ácido Cítrico/química , Difusão , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Radical Hidroxila/química , Ferro/química , Iluminação/instrumentação , Iluminação/métodos , Losartan/metabolismo , Oxirredução , Tartaratos/química , Valsartana/metabolismo , Poluentes Químicos da Água/metabolismo
9.
Photochem Photobiol Sci ; 11(5): 821-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22370626

RESUMO

TiO2 photocatalytic and near-neutral photo-Fenton processes were tested under simulated solar light to degrade two models of natural organic matter - resorcinol (R) (which should interact strongly with TiO2 surfaces) and hydroquinone (H) - separately or in the presence of bacteria. Under similar oxidative conditions, inactivation of Escherichia coli, Shigella sonnei and Salmonella typhimurium was carried out in the absence and in the presence of 10 mg L(-1) of R and H. The 100% abatement of R and H by using a TiO2 photocatalytic process in the absence of bacteria was observed in 90 min for R and in 120 min for H, while in the presence of microorganisms abatement was only of 55% and 35% for R and H, respectively. Photo-Fenton reagent at pH 5.0 completely removed R and H in 40 min, whereas in the presence of microorganisms their degradation was of 60% to 80%. On the other hand, 2 h of TiO2 photocatalytic process inactivated S. typhimurium and E. coli cells in three and six orders of magnitude, respectively, while S. sonnei was completely inactivated in 10 min. In the presence of R or H, the bacterial inactivation via TiO2 photocatalysis was significantly decreased. With photo-Fenton reagent at pH 5 all the microorganisms tested were completely inactivated in 40 min of simulated solar light irradiation in the absence of organics. When R and H were present, bacterial photo-Fenton inactivation was less affected. The obtained results suggest that in both TiO2 and iron photo-assisted processes, there is competition between organic substances and bacteria simultaneously present for generated reactive oxygen species (ROS). This competition is most important in heterogeneous systems, mainly when there are strong organic-TiO2 surface interactions, as in the resorcinol case, suggesting that bacteria-TiO2 interactions could play a key role in photocatalytic cell inactivation processes.


Assuntos
Escherichia coli/metabolismo , Escherichia coli/efeitos da radiação , Compostos Orgânicos/metabolismo , Salmonella typhimurium/metabolismo , Salmonella typhimurium/efeitos da radiação , Shigella sonnei/metabolismo , Shigella sonnei/efeitos da radiação , Desinfecção , Peróxido de Hidrogênio , Hidroquinonas/metabolismo , Ferro , Modelos Biológicos , Fotólise , Espécies Reativas de Oxigênio/metabolismo , Resorcinóis/metabolismo , Luz Solar , Titânio , Microbiologia da Água , Purificação da Água
10.
Chemosphere ; 77(2): 296-300, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19716153

RESUMO

Bacteria inactivation and natural organic matter oxidation in river water was simultaneously conducted via photo-Fenton reaction at "natural" pH ( approximately 6.5) containing 0.6 mg L(-1) of Fe(3+) and 10 mg L(-1) of H(2)O(2). The experiments were carried out by using a solar compound parabolic collector on river water previously filtered by a slow sand filtration system and voluntarily spiked with Escherichia coli. Fifty five percent of 5.3 mg L(-1) of dissolved organic carbon was mineralized whereas total disinfection was observed without re-growth after 24h in the dark.


Assuntos
Desinfecção/métodos , Escherichia coli/efeitos da radiação , Água Doce/microbiologia , Compostos Orgânicos/metabolismo , Luz Solar , Purificação da Água/métodos , Compostos Férricos/química , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio
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