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1.
Environ Pollut ; 274: 116597, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33540255

RESUMO

Due to the unreasonable use and discharge of the aquaculture industry, over standard of the antibiotics has been frequent in different types of water environments, causing adverse effects on aquatic organisms. Lycopene (LYC) is an esculent carotenoid, which is considered to be a strong antioxidant. This study was designed to explore the therapeutic effect of LYC on antibiotic (sulfamethoxazole (SMZ)) induced intestinal injury in grass carp Ctenopharyngodon idella. The 120 carps (the control, LYC, SMZ, and co-administration groups) were treated for 30 days. We found that treatment with LYC significantly suppressed SMZ-induced intestinal epithelial cell damage and tight junction protein destruction through histopathological observation, transmission electron microscopy and detection of related genes (Claudin-1/3/4, Occludin and zonula occludens (ZO)-1/2). Furthermore, LYC mitigated SMZ-induced dysregulation of oxidative stress markers, including elevated malondialdehyde (MDA) levels, and consumed super oxide dimutese (SOD), catalase (CAT) activities and glutathione (GSH) content. In the same treatment, LYC reduced inflammation and apoptosis by a detectable change in pro-inflammatory factors (tumor necrosis factor-alpha (TNF-ß), interleukin (IL)-1ß, IL-6 and IL-8), anti-inflammatory factors (transforming growth factor-beta (TGF-ß) and IL-10) and pro-apoptosis related genes (p53, p53 upregulated modulator of apoptosis (PUMA), Bax/Bcl-2 ratio, caspase-3/9). In addition, activation of autophagy (as indicated by increased autophagy-related genes through AMPK/ATK/MTOR signaling pathway) under the stress of SMZ was also dropped back to the original levels by LYC co-administration. Collectively, our findings identified that LYC can serve as a protectant agent against SMZ-induced intestinal injury.


Assuntos
Carpas , Ração Animal/análise , Animais , Carpas/metabolismo , Dieta , Proteínas de Peixes/metabolismo , Intestinos , Licopeno , Estresse Oxidativo , Sulfametoxazol
2.
Artigo em Inglês | MEDLINE | ID: mdl-33535451

RESUMO

The presence of contaminants of emerging concern (CECs) in the aquatic environment has recently become a global issue. The very large number of CECs reported in the literature makes it difficult to interpret potential risks as well as the removal efficiencies, especially for the more recalcitrant compounds. As such, there is a need for indicator compounds that are representative of CECs detected in systems worldwide. In an effort to develop such a list, five criteria were used to address the potential for applying indicator compounds; these criteria include usage, occurrence, resistance to treatment, persistence, and physicochemical properties that shed light on the potential degradability of a class of compounds. Additional constraints applied included the feasibility of procuring and analyzing compounds. In total, 22 CECs belonging to 13 groups were selected as indicator compounds. These compounds include acetaminophen and ibuprofen (analgesic); erythromycin, sulfamethoxazole, and trimethoprim (antibiotics); diazepam and fluoxetine (antidepressants); carbamazepine (antiepileptic); atenolol and propranolol (ß-blockers); gemfibrozil (blood lipid regulator); tris(2-chloroethyl)phosphate (TCEP) (fire retardant); cotinine (nicotine metabolite); atrazine, metolachlor, and N,N-diethyl-meta-toluamide (DEET) (pesticides); 17ß-estradiol and cholesterol (steroids); caffeine (psychomotor stimulant); perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) (surfactants); and iopromide (X-ray contrast agent). These thirteen groups of compounds represent CECs with the greatest resistance to treatment processes, most persistent in surface waters, and detected with significant frequency throughout the water cycle. Among the important implications of using indicator compounds are the ability to better understand the efficacy of treatment processes as well as the transport and fate of these compounds in the environment.


Assuntos
Praguicidas , Poluentes Químicos da Água , Monitoramento Ambiental , Praguicidas/análise , Sulfametoxazol , Estados Unidos , Águas Residuárias , Ciclo Hidrológico , Poluentes Químicos da Água/análise
3.
Sci Total Environ ; 772: 145468, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33581539

RESUMO

Extensive research has been performed on the utilization of biochar for pollutant removal via sorption. Additionally, the relationship between sorption strength of organic pollutants by organic matter and nanomaterials and their sorption site energy distribution has been studied. However, the linkage between removal efficiency of organic pollutants and the sorption site energy distribution on biochars is unknown. As a first attempt to address this knowledge gap, three biochars were derived from two plant-origin precursors (corn straw-CS; birch sawdust-BS) and one animal-origin precursor (meat and bone meal-MBM) at 500 °C (CS-500, BS-500, and MBM-500). In addition, two biochars were prepared with CS at 300 and 800 °C (CS-300 and CS-800) to examine the relationship between their site energy distribution and removal efficiency of antibiotics including sulfadiazine (SDZ), sulfamethoxazole (SMX), tetracycline (TC) and ciprofloxacin (CFX) by these materials. Our findings showed that the antibiotic-biochar interactions can be well interpreted with site energy distribution and XPS analysis results. Polar interactions between CS-300, CS-500, and CS-800 and SDZ and SMX occurring at the high-energy sites dominated their removal. However, TC and CFX removal by these biochars was driven by their polar interactions occurring at high-energy sites and π-π interactions at low-energy sites. The π-π stacking mechanism tended to dominate their removal with increasing charring temperature. Abundance of polar functionalities on CS-500, BS-500, and MBM-500 and TC removal efficiency of these materials consistently followed an order of MBM-500 > CS-500 > BS-500, highlighting importance of precursors for making biochars and polar interactions in its removal.


Assuntos
Antibacterianos , Carvão Vegetal , Adsorção , Animais , Sulfametoxazol
4.
Environ Sci Technol ; 55(5): 3270-3282, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33566597

RESUMO

Microbial communities are believed to outperform monocultures in the complete catabolism of organic pollutants via reduced metabolic burden and increased robustness to environmental challenges; however, the interaction mechanism in functional microbiomes remains poorly understood. Here, three functionally differentiated activated sludge microbiomes (S1: complete catabolism of sulfamethoxazole (SMX); S2: complete catabolism of the phenyl part of SMX ([phenyl]-SMX) with stable accumulation of its heterocyclic product 3-amino-5-methylisoxazole (3A5MI); A: complete catabolism of 3A5MI rather than [phenyl]-SMX) were enriched. Combining time-series cultivation-independent microbial community analysis, DNA-stable isotope probing, molecular ecological network analysis, and cultivation-dependent function verification, we identified key players involved in the SMX degradation process. Paenarthrobacter and Nocardioides were primary degraders for the initial cleavage of the sulfonamide functional group (-C-S-N- bond) and 3A5MI degradation, respectively. Complete catabolism of SMX was achieved by their cross-feeding. The co-culture of Nocardioides, Acidovorax, and Sphingobium demonstrated that the nondegraders Acidovorax and Sphingobium were involved in the enhancement of 3A5MI degradation. Moreover, we unraveled the internal labor division patterns and connections among the active members centered on the two primary degraders. Overall, the proposed methodology is promisingly applicable and would help generate mechanistic, predictive, and operational understanding of the collaborative biodegradation of various contaminants. This study provides useful information for synthetic activated sludge microbiomes with optimized environmental functions.


Assuntos
Microbiota , Poluentes Químicos da Água , Antibacterianos , Biodegradação Ambiental , Interações Microbianas , Esgotos , Sulfametoxazol
5.
Sci Total Environ ; 773: 145057, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33592457

RESUMO

Pharmaceuticals of emerging concern (acetaminophen (ACM), trimethoprim (TMP), oxytetracycline (OTC), and sulfamethoxazole (SMX)) were detected in water samples from aquaculture environments and nonaquaculture sites in four regions located on the northern coast of Central Java. ACM was the most prevalent pharmaceutical, with a mean concentration ranging from not detected (n.d.) to 5.5 ± 1.9 ngL-1 (Brebes). Among the target antibiotics (TMP, OTC, SMX), OTC was the most ubiquitous, with a mean concentration varying from n.d. to 8.0 ± 3.3 ngL-1. Correlation analysis demonstrated that there was a significant correlation between TMP and SMX concentrations. Based on ecological risk assessment evaluation, the use of OTC requires serious consideration, as it presented high health risks to algae, while ACM, TMP, and SMX posed an insignificant to moderate risk to algae, invertebrates, and fish. The findings obtained from this study highlight OTC as an emerging contaminant of prominent concern. More attention needs to be given to managing and planning for the sustainable management of shrimp farms, particularly in the northern part of Central Java.


Assuntos
Oxitetraciclina , Poluentes Químicos da Água , Animais , Aquicultura , Indonésia , Sulfametoxazol , Poluentes Químicos da Água/análise
6.
Ecotoxicol Environ Saf ; 210: 111831, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33388591

RESUMO

The effects of bioaugmentation with immobilized Penicillium restrictum on the removal efficiency of sulfamethoxazole (SMX), erythromycin (ERY) and tetracycline (TC) antibiotics as well as membrane biofouling was studied using hollow-fiber membrane bioreactor (HF-MBR). Bioaugmentation with P. restrictum led to a significant change in the antibiotic removal efficiency and relative abundance of aerobic microbial community, most probably as a result of its quorum quenching activity. Furthermore, in addition to its role in the increase of SMX and ERY removal efficiencies and the decrease of their sorption on solid phase, bioaugmentation significantly reduced the transmembrane pressure which in turn reduced membrane clogging. The most abundant phyla in sludge and biofilm samples in the presence of P. restrictum were observed to be Proteobacteria, Bacteroidetes and Firmicutes. Differences in bacterial compositions and their specificity in biodegradation of antibiotics in different reactors showed that bacteria were specifically selected under the pressure of antibiotics and growing fungus.


Assuntos
Antibacterianos/metabolismo , Reatores Biológicos/microbiologia , Penicillium/fisiologia , Bactérias/metabolismo , Biodegradação Ambiental , Biofilmes , Incrustação Biológica , Eritromicina/metabolismo , Membranas Artificiais , Microbiota , Percepção de Quorum , Sulfametoxazol/metabolismo , Tetraciclina/metabolismo , Águas Residuárias/microbiologia
7.
Environ Pollut ; 271: 116382, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33387786

RESUMO

Coupling of nitrogen removal processes with nitrification (NRn) are vital synergistic nitrogen elimination mechanisms in aquatic environments. However, the effects of antibiotics on NRn are not well known. In the present work, 20-day continuous-flow experiments combined with 15N tracing techniques and quantitative PCR were performed to simulate the impact of sulfamethoxazole (SMX, a sulfonamide antibiotic) with near in situ concentration on NRn processes in sediments of Yangtze Estuary. Results showed that SMX with near in situ concentration significantly decreased NRn, NRw (uncoupling of nitrogen removal processes with nitrification) and actual nitrogen removal rates via inhibiting nitrogen transformation functional genes (AOB, narG, nirS, nosZ) and anammox 16S rRNA gene, while the coupling links between nitrification and nitrogen removal processes were not broken by the exposure. The proportion of NRn in total nitrogen removal processes decreased by approximately 10% with SMX addition, due to the different inhibition on AOB, denitrifying genes and anammox 16S rRNA gene. N2O production and nitrite accumulation remarkably increased with SMX addition under simultaneous nitrification and denitrification, and they strongly correlated with each other. The more severely inhibition on nirS gene (13.6-19.8%) than Nitrospira nxrB gene (0.3-8.2%) revealed that the increased nitrite accumulation with SMX addition mainly occurred in heterotrophic denitrification, suggesting that the increased N2O production was dominated by the heterotrophic nitrite reduction. Moreover, we estimated that the ratio of external inorganic N eliminated by actual nitrogen removal can upgrade to 6.4-7.4% under circumstances of no inhibition by SMX. This study revealed the effects of SMX with near in situ concentration on NRn processes and illustrated the microbial mechanism on functional genes level. Our results highlighted the inhibitory effects of SMX on NRn may contribute to reactive N retention and N2O production in estuarine and coastal ecosystems.


Assuntos
Nitrificação , Nitrogênio , Desnitrificação , Ecossistema , Estuários , Nitrogênio/análise , RNA Ribossômico 16S/genética , Sulfametoxazol
8.
Water Res ; 190: 116777, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33387956

RESUMO

Advanced oxidation processes (AOP) based on nonradicals have attracted growing attentions because nonradical systems require much less oxidants and have low susceptibility to radical scavengers. Herein, a novel Fenton-like system that utilizes nonradicals was explored. It was derived from g-C3N4/MgO activated H2O2, and can reduce the H2O2 stoichiometry from 0.94%-0.18% to 0.03%. Sulfamethoxazole (SMX), a widely used sulfonamide, was used as the model pollutant to evaluate the efficacy of the system. It was observed for the first time that organic pollutants can be degraded with singlet oxygen (1O2) through a nonradical pathway in the g-C3N4/MgOH2O2 system. The reduced H2O2 consumption was the net result of continuously-recycled H2O2 from the reactions between H2O2 and g-C3N4/MgO. Based on experimental results and theoretical calculations, the synthesis of g-C3N4 and MgO forms a N-Mg bond with strong ability to absorb electrons and the electron transfer of H2O2 to N-Mg bonding is accelerated, activation of H2O2 to generate 1O2. Experimental data showed that organic pollutants can be degraded rapidly over a wide pH range. Findings of this study point to a cyclical but stable Fenton-like system with reduced H2O2 requirement for cost-effective remediation and treatment of organic pollutants and toxic wastes.


Assuntos
Peróxido de Hidrogênio , Sulfametoxazol , Óxido de Magnésio , Oxidantes , Oxirredução
9.
Artigo em Inglês | MEDLINE | ID: mdl-33499398

RESUMO

Antibiotics are frequently applied to treat bacterial infections in humans and animals. However, most consumed antibiotics are excreted into wastewater as metabolites or in their original form. Therefore, removal of antibiotics from aquatic environments is of high research interest. In this study, we investigated the removal of sulfamethoxazole (SMX) and ofloxacin (OFX) with Chaetoceros muelleri, a marine diatom. The optimization process was conducted using response surface methodology (RSM) with two independent parameters, i.e., the initial concentration of antibiotics and contact time. The optimum removal of SMX and OFX were 39.8% (0.19 mg L-1) and 42.5% (0.21 mg L-1) at the initial concentration (0.5 mg L-1) and contact time (6.3 days). Apart from that, the toxicity effect of antibiotics on the diatom was monitored in different SMX and OFX concentrations (0 to 50 mg L-1). The protein (mg L-1) and carotenoid (µg L-1) content increased when the antibiotic concentration increased up to 20 mg L-1, while cell viability was not significantly affected up to 20 mg L-1 of antibiotic concentration. Protein content, carotenoid, and cell viability decreased during high antibiotic concentrations (more than 20 to 30 mg L-1). This study revealed that the use of Chaetoceros muelleri is an appealing solution to remove certain antibiotics from wastewater.


Assuntos
Diatomáceas , Poluentes Químicos da Água , Animais , Antibacterianos/toxicidade , Biodegradação Ambiental , Humanos , Sulfametoxazol , Águas Residuárias , Poluentes Químicos da Água/toxicidade
10.
Sci Total Environ ; 762: 144102, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33360461

RESUMO

In this study, laboratory column experiments under water saturated conditions were conducted for over 35 days to investigate the transport of nine pharmaceuticals (nadolol, sulfamethizole, sulfamethoxazole, sulfamethoxypyridazine, carbamazepine, ibuprofen, diclofenac, hydrochlorothiazide, and gemfibrozil) and four artificial sweeteners (acesulfame, saccharin, cyclamate, and sucralose) in two soils (S and C) with similar organic carbon content (between 0.8 and 1.1%) and pH (7.90 and 7.25) but different texture (58.3 and 85.5% of silt+clay, respectively). Ibuprofen and artificial sweeteners reached maximum concentrations at the outlet of the columns and showed a homogenous vertical profile in the aqueous phase, with the same concentration in all sampling ports under flow percolation conditions. Regarding carbamazepine and hydrochlorothiazide, apparent retardation was observed for both and was attributed to sorption. Nadolol, a positively charged beta-blocker, did not show any apparent breakthrough. After 35 days, the columns were washed using tap water for over one week. Soils were then analyzed at different depths and vertical concentration profiles were plotted. Overall, highest concentrations were measured in the top most layers for contaminants in the soil column with higher clay content (C), whereas vertical profiles were more uniform in that with lower clay content (S).


Assuntos
Poluentes do Solo , Solo , Carbamazepina/análise , Ibuprofeno , Poluentes do Solo/análise , Sulfametoxazol
12.
Bioresour Technol ; 319: 124067, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33035865

RESUMO

The individual and combined effects of sulfamethoxazole (SMX) and oxytetracycline (OTC) on an enhanced biological phosphorus removal (EBPR) system was investigated. OTC at 5 mg/L resulted in filamentous bulking with a collapse of EBPR system. P removal decreased to 44.8% and COD was mostly removed during the aerobic phase. SMX and OTC had antagonistic effects in EBPR system. The inhibitory effect of SMX and SMX + OTC on P removal, COD removal, glycogen transformation and extracellular polymeric substances content was reversible with prolonged operation, accompanied with increase of polyphosphate accumulating organisms. The presence of nitrification inhibitor allylthiourea, high pH and low tetX abundance limited the removal of SMX and OTC. The bacterial community structure, antibiotic resistance genes abundances and genes functions were also investigated by metagenomic analysis. The results of this study offer insights into the individual and combined environmental risks of SMX and OTC, and their impact on EBPR.


Assuntos
Oxitetraciclina , Antibacterianos/farmacologia , Reatores Biológicos , Resistência Microbiana a Medicamentos , Fósforo , Sulfametoxazol
13.
Chemosphere ; 262: 127677, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32763571

RESUMO

Plant uptake of antibiotics raises serious food safety concerns. Measurements and predictions of antibiotic uptake by plants are often based on root concentration factors (RCF) determined using antibiotic concentrations in bulk soil (RCFbs) rather than in rhizosphere soil (RCFrs) where root uptake actually occurs. This study investigated the fate and transport of nine antibiotics in the continuum of bulk soil, rhizosphere soil, roots and shoots of lettuce (Lactuca sativa) under soil-surface irrigation. Antibiotic concentrations in the lettuce shoots remained unchanged during 25-35 days after seedling transplantation. Compared with the RCFrs values, the RCFbs values were significantly greater for ciprofloxacin, lincomycin, oxytetracycline, sulfamethoxazole, and tetracycline (p < 0.05), similar for trimethoprim and tylosin, but significantly lower for monensin (p < 0.05). Ciprofloxacin, trimethoprim, and tylosin had the lowest translocation factors (TF) ranging between 0.03 and 0.05, suggesting their limited upward transport to the lettuce shoots. Oxytetracycline, monensin, and sulfamethoxazole had intermediate TF values of 0.36-0.64, whereas lincomycin had the highest TF value of 1.46. This study showed significant differences between RCFbs and RCFrs values, suggesting the need to reassess the utility of RCFbs in predicting the antibiotic root uptake in diverse soil-plant systems.


Assuntos
Antibacterianos/metabolismo , Alface/metabolismo , Poluentes do Solo/metabolismo , Ciprofloxacino , Raízes de Plantas/química , Rizosfera , Solo , Poluentes do Solo/análise , Sulfametoxazol , Trimetoprima , Tilosina
14.
Chemosphere ; 262: 127741, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32781330

RESUMO

In recent years, the dramatic increase in antibiotic use has led to the evolution of antibiotic resistant genes (ARGs), posing a potential risk to human and aquatic ecological safety. In this study, source contribution and correlations between twelve antibiotics and their corresponding ARGs were firstly investigated in surface water in the Fuxian Lake. The results showed that sulfamethoxazole (SMX) (0.98-14.32 ng L-1) and ofloxacin (OFL) (0.77-7.3 ng L-1) were the dominant antibiotics in surface water, whereas erythromycin-H2O (EM-H2O), SMX and OFL posed the medium risk to aquatic organisms. Meanwhile, the mean concentrations of MLs in inflowing rivers were 5.6 times more than those in the lake, which was related to dilution and degradation. Moreover, the facter1 (co-sources L (Living quarters), M (Mining area), A (Agricultural district) and T (tourist area)) contributed 78% of antibiotic concentrations, and the source L was predominant. The results also revealed the prevalence of intL1, sul1 and sul2 in all the sampling sites, and that the abundance of ARGs in the lake was significantly lower (P < 0.01) than that in inflowing rives. Additionally, significant correlations (p < 0.0001) between intL1 and sulfanilamide resistance genes (sul1, sul2) were detected, indicating that intL1 promoted the propagation and they originated from the same anthropogenic sources. Overall, our findings revealed the presence of antibiotics and ARGs and their inconsistent correlations in the Fuxian Lake, which provides a foundation to support further exploration of the occurrence and transmission mechanisms of antibiotics and ARGs.


Assuntos
Antibacterianos/análise , Resistência Microbiana a Medicamentos/genética , Lagos , Poluentes Químicos da Água/análise , China , Lagos/análise , Lagos/microbiologia , Modelos Lineares , Ofloxacino/análise , Análise de Componente Principal , Rios , Sulfametoxazol/análise , Microbiologia da Água
15.
Chemosphere ; 263: 127964, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32822941

RESUMO

To enhance the mineralization of toxic organic pollutants is crucial for the alleviation of environmental pollution. In this study, the successive non-radicals and radicals process (SNRP) of peroxymonosulfate (PMS)-based oxidation was performed using various methods for PMS activation, including UV, ozone, gamma radiation and biochar and applied for enhancing the mineralization of sulfamethoxazole (SMX). The results showed that SNRP-UV could improve the mineralization of SMX, and both SNRP-UV and PMS/UV could completely mineralize SMX. For SNRP-Ozone, SNRP-Radiation and SNRP-Biochar, compared to the sole radical oxidation, all SNRPs could enhance the mineralization of SMX. The biochar-induced SNRP obtained the maximum mineralization increment, followed by gamma irradiation-induced SNRP and ozone-induced SNRP. Sulfate radicals were mainly responsible for SMX mineralization for SNRP-Biochar, while hydroxyl radicals for SNRP-Radiation, and the synergetic effect of ozone and sulfate radicals for SNRP-Ozone. Different degradation intermediate products were identified in different SNRP, further revealing that SNRP induced by different methods had different mineralization capacity. This study further demonstrated that SNRP could be a new strategy for enhancing the mineralization of SMX.


Assuntos
Peróxidos/química , Sulfametoxazol/química , Poluentes Químicos da Água/química , Carvão Vegetal , Radical Hidroxila , Oxirredução , Peróxidos/análise , Sulfatos , Poluentes Químicos da Água/análise
16.
Ecotoxicol Environ Saf ; 207: 111258, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32971319

RESUMO

This study investigated whether bioaugmentation improves sulfamethoxazole (SMX) degradation and nitrogen removal in the Moving Bed Biofilm Reactor (MBBR) system. The effects of the C/N ratio on SMX degradation and nitrogen removal were also evaluated. Using MBBR system operation experiments, the bioaugmented reactor was found to perform more effectively than the non-bioaugmentation reactor, with the highest SMX, nitrate-N, and ammonia-N removal efficiencies of 80.49, 94.70, and 96.09%, respectively. The changes in the sulfonamide resistance genes and bacterial communities were detected at various operating conditions. The results indicate that the diversity of the bacterial communities and the abundance of resistance genes were markedly influenced by bioaugmentation and the C/N ratio, with Achromobacter among the dominant genera in the MBBR system. The bio-toxicity of samples, calculated as the inhibition percentage (IP) toward Escherichia coli, was found to decrease to non-toxic ranges after treatment.


Assuntos
Aquicultura , Sulfametoxazol/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Achromobacter/metabolismo , Amônia , Biofilmes , Reatores Biológicos/microbiologia , Nitratos , Nitrogênio , Águas Residuárias/microbiologia
17.
Water Res ; 188: 116472, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33027697

RESUMO

Continuous development of industry and civilization has led to changes in composition, texture and toxicity of waste water due to the wide range of pollutants being present. Considering that the conventional wastewater treatment methods are insufficient for removing micropollutants and nutrients to a high level, other, alternative, treatment methods should be used to polish wastewater treatment plant effluents. In this study we developed an alternative, polishing concept for removal of ammonium and micropollutants that could potentially be incorporated in existing wastewater treatment plants. We demonstrated a method to use high silica MOR zeolite granules as an adsorbent for simultaneous removal of the micropollutant sulfamethoxazole (SMX) and ammonium (NH4+) ions from aqueous solutions. At an initial NH4+ concentration of 10 mg/L the high silica zeolite mordenite (MOR) granules removed 0.42 mg/g of NH4+, similar to the removal obtained by commonly used natural zeolite Zeolita (0.44 mg/g). However, at higher NH4+ concentrations the Zeolita performed better. In addition, the Langmuir isotherm model showed a higher maximum adsorption capacity of Zeolita (qmax, 4.08 mg/g), which was about two times higher than that of MOR (2.11). The adsorption capacity of MOR towards SMX, at both low (2 µg/L) and high (50 mg/L) initial concentrations, was high and even increased in the presence of NH4+ ions. The used adsorbent could be regenerated with ozone and reused in consecutive adsorption-regeneration cycles with marginal decrease in the total adsorption capacity.


Assuntos
Compostos de Amônio , Ozônio , Poluentes Químicos da Água , Purificação da Água , Zeolitas , Adsorção , Dióxido de Silício , Sulfametoxazol
18.
Water Res ; 188: 116480, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33065414

RESUMO

Sulfamethoxazole (SMX) is the most widely distributed sulfonamide antibiotics detected in decentralized poultry wastewater in rural communities. As an economically-feasible and eco-friendly technology for decentralized wastewater treatment in rural areas, vertical-flow multi-soil-layering (MSL) system was promising to mitigate the ecological and human health risks from SMX in such areas. The treatment of SMX-contained poultry wastewater by using MSL systems was investigated for the first time, and the main and interactive effects of related multiple variables on system performance were explored through factorial analysis, including material of permeable layer, concentration of SMX, and pH of influent. Results indicated that SMX concentration and pH of influent showed significantly negative effects on SMX removal. Medical stone used in MSL systems with larger surface area could intensify the SMX removal compared to anthracite. MSL systems showed stable performances on SMX removal with the best SMX removal efficiency more than 91%. A novel stepwise-cluster inference (SCI) model was developed for the first time to map the multivariate numeric relationships between state variables and SMX removal under discrete and nonlinear complexities. It was demonstrated that the effect of SMX in wastewater with high concentration was significant on the differentiation of soil bacteria composition in MSL systems based on microbial diversity analysis. These results can help better understand the mechanism of SMX removal in MSL systems from perspectives of factorial analysis, numeric modeling, and microbiological change.


Assuntos
Solo , Águas Residuárias , Animais , Humanos , Aves Domésticas , População Rural , Sulfametoxazol
19.
Chemosphere ; 262: 127840, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32763570

RESUMO

This work assessed the effect of the antibiotics trimethoprim (TMP) and sulfamethoxazole (SMX) on the granulation process, microbiology, and organic matter and nutrient removal of an aerobic granular sludge (AGS) system. In addition, after the maturation stage, the impact of the redox mediator anthraquinone-2,6-disulfonate (AQDS) (25 µM) on the biotransformation of the antibiotics was evaluated. The reactor R1 was maintained as a control, and the reactor R2 was supplemented with TMP and SMX (200 µg L-1). The ability to remove C, N, and P was similar between the reactors. However, the structural integrity of the AGS was impaired by the antibiotics. Low TMP (∼30%) and SMX (∼60%) removals were achieved when compared to anaerobic or floccular biomass aerobic systems. However, when the system was supplemented with AQDS, an increase in the removal of TMP (∼75%) and SMX (∼95%) was observed, possibly due to the catalytic action of the redox mediator on cometabolic processes. Regarding the microbial groups, whereas Proteobacteria and Bacterioidetes increased, Planctomycetes decreased in both reactors. However, TMP and SMX presence seemed to inhibit or favor some genera during the formation of the granules, possibly due to their bactericidal action.


Assuntos
Microbiota/efeitos dos fármacos , Sulfametoxazol/toxicidade , Trimetoprima/toxicidade , Eliminação de Resíduos Líquidos , Antibacterianos , Bactérias/efeitos dos fármacos , Biomassa , Esgotos , Sulfametoxazol/química , Trimetoprima/química , Microbiologia da Água
20.
Sci Total Environ ; 750: 141691, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32853938

RESUMO

This work focused on the impacts of FeCl3 impregnation ratio on the properties of FeCl3-activated bermudagrass (BG)-derived biochars (IA-BCs), adsorption of sulfamethoxazole (SMX) onto IA-BCs and regeneration of SMX-spent IA-BC. Compared with the control BC (85.82 m2/g), IA-BCs made via pyrolysis with FeCl3 to BG mass ratio between 1 and 3 (1-3 g FeCl3/g BG) resulted in significantly enhancing surface area (1014-1035 m2/g), hydrophobicity, Fe content in IA-BCs (3.87-7.27%), and graphitized carbon. The properties of IA-BCs supported magnetic separation and higher adsorption (32-265 mg SMX/g BC) than the control BC (6-14 mg SMX/g BC) at various pH. Adsorption experiments indicated various adsorption mechanisms between SMX and IA-BCs via π-π EDA, hydrophobic interactions, and hydrogen bond with intraparticle diffusion limitation. The adsorption was also found to be spontaneous and exothermic. The IA-BC made at FeCl3 to BG mass ratio of 2 (IA-BC2.0) showed the maximum adsorption capacity for SMX (253 mg SMX/g BC) calculated from Langmuir isotherm model. Additionally, both NaOH desorption and thermal oxidation showed effective regeneration of SMX-saturated IA-BC2.0 over multiple cycles. After three cycles of adsorption-regeneration, 64% and 62% of regeneration efficiencies were still achieved under thermal treatment at 300 °C and desorption with 0.1 M NaOH solution, respectively, indicating a cost-efficient adsorbent for the elimination of SMX in water.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Carvão Vegetal , Cynodon , Ferro , Sulfametoxazol , Poluentes Químicos da Água/análise
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