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The periphery of the hospital water system interfaces at multiple points with patients and staff in clinical areas. This comprises mostly sinks and showers and presents a significant infection control risk. Wastewater drains in particular act as a reservoir of pathogens that can be transmitted to patients. Numerous strategies have been investigated as potential methods to reduce biofilm and bacterial load including regular application of biocidal chemicals. Traditional methods of assessing the efficacy of such products relies on culture-based microbiological techniques, usually targeting a limited range of key pathogens. We assessed the efficacy of a peracetic acid containing drain disinfectant product on seven clinical handwash basin drains, taking daily samples over six weeks (before, during and after use of the drain disinfectant product). We used a rapid, culture-independent estimation of total bacterial viable count (TVC) to assess efficacy. We applied long-read metagenomic sequencing to study the entire drain microbiome, which allowed taxonomic changes to be documented following use of the drain disinfectant product. All samples were found to be heavily contaminated, however the drain disinfectant product reduced the TVC from an estimated mean of 4228 cfu/mL to 2874 cfu/mL. This reduction was sustained in the two weeks following cessation of the product. Long-read metagenomic sequencing showed a microbiome dominated with Gram-negative organisms, with some taxonomic shifts in samples before and after application of the drain disinfectant. The impact on hospital-acquired infections from reducing bioburden in hospital drains by approximately a third, along with any associated changes in bacterial composition, needs evaluation in future studies. [ABSTRACT FROM AUTHOR]

Environmental release of wastewater that contains cytostatic drugs can cause genotoxic impact, since these drugs act directly on the genetic material of aquatic organisms. Thus, the aim of this study was to evaluate the removal of the cytostatic drugs cytarabine (CTR) and methotrexate (MTX) using different physico-chemical methods individually (i.e. US, O3, H2O2 and UV) and combined (i.e. O3/US, US/H2O2, O3/H2O2 and O3/US/H2O2) under different pH conditions (4, 7 and 10). In the degradation tests, the efficiency of the methods applied was found to be dependent on the pH of the solution, with the degradation of CTR being better at pH 4 and MTX at pH 7 and pH 10. The US, H2O2 and US + H2O2 methods were the least efficient in degrading CTR and MTX under the pH conditions tested. The highest MTX degradation rate after 16 min of treatment at pH 7 was achieved by the O3 + H2O2 method (97.05% – C/C0 = 0.0295). For CTR, the highest degradation rate after 16 min of treatment was achieved by the O3 process (99.70% – C/C0 = 0.0030) at pH 4. In conclusion, most of the treatment methods tested for the degradation of CTR and MTX are effective. Notably, ozonolysis is an efficient process applied alone. Also, in combination with other methods (US + O3, O3 + H2O2 and O3 + H2O2 + US) it increases the degradation performance, showing a rapid removal rate of 70–94% in less than 4 min of treatment. [ABSTRACT FROM AUTHOR]

The problem of antimicrobial resistance (AMR) is not limited to the medical field but is also becoming prevalent on a global scale in the environmental field. Environmental water pollution caused by the discharge of wastewater into aquatic environments has caused concern in the context of the sustainable development of modern society. However, there have been few studies focused on the treatment of hospital wastewater, and the potential consequences of this remain unknown. This study evaluated the efficacy of the inactivation of antimicrobial-resistant bacteria (AMRB) and antimicrobial resistance genes (AMRGs) in model wastewater treatment plant (WWTP) wastewater and hospital effluent based on direct ultraviolet (UV) light irradiation provided by a conventional mercury lamp with a peak wavelength of 254 nm and an ultraviolet light-emitting diode (UV-LED) with a peak emission of 280 nm under test conditions in which the irradiance of both was adjusted to the same intensity. The overall results indicated that both UV- and UV-LED-mediated disinfection effectively inactivated the AMRB in both wastewater types (>99.9% after 1–3 min of UV and 3 min of UV-LED treatment). Additionally, AMRGs were also removed (0.2–1.4 log10 for UV 254 nm and 0.1–1.3 log10 for UV 280 nm), and notably, there was no statistically significant decrease (p < 0.05) in the AMRGs between the UV and UV-LED treatments. The results of this study highlight the importance of utilizing a local inactivation treatment directly for wastewater generated by a hospital prior to its flow into a WWTP as sewage. Although additional disinfection treatment at the WWTP is likely necessary to remove the entire quantity of AMRB and AMRGs, the present study contributes to a significant reduction in the loads of WWTP and urgent prevention of the spread of infectious diseases, thus alleviating the potential threat to the environment and human health risks associated with AMR problems. [ABSTRACT FROM AUTHOR]

The increase in the prevalence of carbapenem-resistant Gram-negative bacteria, in particular Acinetobacter baumannii (CRAB) and Pseudomonas aeruginosa (CRPA), poses a serious threat for public health worldwide. This article reviews the alarming data on the prevalence of infections caused by CRAB and CRPA pathogens and their presence in hospital and municipal wastewater, and it highlights the environmental impact of antibiotic resistance. The article describes the key role of antibiotic resistance genes (ARGs) in the acquisition of carbapenem resistance and sheds light on bacterial resistance mechanisms. The main emphasis was placed on the transfer of ARGs not only in the clinical setting, but also in the environment, including water, soil, and food. The aim of this review was to expand our understanding of the global health risks associated with CRAB and CRPA in hospital and municipal wastewater and to analyze the spread of these micropollutants in the environment. A review of the literature published in the last decade will direct research on carbapenem-resistant pathogens, support the implementation of effective preventive measures and interventions, and contribute to the development of improved strategies for managing this problem. [ABSTRACT FROM AUTHOR]

Qianwen Zhang,1,&ast; Shengcen Zhang,1,&ast; Binbin Xu,1 Luyan Dong,1 Zhichang Zhao,2 Bin Li1 1Department of Clinical Laboratory, Fujian Medical University Union Hospital, Fujian, 350001, People’s Republic of China; 2Department of Pharmacy, Fujian Medical University Union Hospital, Fuzhou, Fujian, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Bin Li, Department of Clinical Laboratory, Fujian Medical University Union Hospital, Fujian, 350001, People’s Republic of China, Email leonlee307@hotmail.com Zhichang Zhao, Department of Pharmacy, Fujian Medical University Union Hospital, Fuzhou, Fujian, People’s Republic of China, Email slip2046@126.comBackground: Hospital wastewater (HWW) promotes the spread of carbapenem resistance genes (CRGs). Aeromonas carry a large number of CRGs in HWW, they may play a role as a suitable reservoir for CRGs, while resistomes in HWW are still poorly characterized regarding carbapenem resistant Aeromonas. Thus, the aim of the study was to evaluate the molecular epidemiological characteristics of carbapenem resistant Aeromonas in HWW.Methods: A total of 33 carbapenem resistant Aeromonas were isolated from HWW. Antimicrobial susceptibility testing and polymerase chain reaction (PCR) were used to assess the antimicrobial resistance profiles. Molecular typing was performed using enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) and multilocus sequence typing (MLST). The horizontal transmission mode of blaKPC was explored through conjugation and transformation experiments. The stability of blaKPC-IncP-6 plasmids was assessed through plasmid stability and in vitro competition test. The PCR mapping method was used to investigate the structural diversity of blaKPC.Results: The detection rates of blaKPC and cphA in Aeromonas were 97.0% and 39.4% respectively. Aeromonas caviae were grouped into 13 clusters by ERIC-PCR and 12 STs by MLST. Aeromonas veronii were grouped into 11 clusters by ERIC-PCR and 4 STs by MLST. 56.3% blaKPC were located on mobilizable IncP-6 plasmids. blaKPC-IncP-6 plasmid showed high stability and low cost fitness.Conclusion: Carbapenem resistant Aeromonas from HWW mainly carried blaKPC, which exhibited great structural diversity. Aeromonas might serve as reservoirs for blaKPC and blaKPC might spread mainly through transformation in HWW.Keywords: hospital wastewater, carbapenem resistance, Aeromonas, IncP-6, blaKPC

Hospital wastewater has been identified as a hotspot for the emergence and transmission of multidrug-resistant (MDR) pathogens that present a serious threat to public health. Therefore, we investigated the current status of antibiotic resistance as well as the phenotypic and genotypic basis of biofilm formation in Pseudomonas aeruginosa from hospital wastewater in Dhaka, Bangladesh. The disc diffusion method and the crystal violet assay were performed to characterize antimicrobial resistance and biofilm formation, respectively. Biofilm and integron-associated genes were amplified by the polymerase chain reaction. Isolates exhibited varying degrees of resistance to different antibiotics, in which >80% of isolates showed sensitivity to meropenem, amikacin, and gentamicin. The results indicated that 93.82% of isolates were MDR and 71 out of 76 MDR isolates showed biofilm formation activities. We observed the high prevalence of biofilm-related genes, in which algD+pelF+pslD+ (82.7%) was found to be the prevalent biofilm genotypic pattern. Sixteen isolates (19.75%) possessed class 1 integron (int1) genes. However, statistical analysis revealed no significant association between biofilm formation and multidrug resistance (χ2 = 0.35, P = 0.55). Taken together, hospital wastewater in Dhaka city may act as a reservoir for MDR and biofilm-forming P. aeruginosa, and therefore, the adequate treatment of wastewater is recommended to reduce the occurrence of outbreaks. HIGHLIGHTS A high occurrence of P. aeruginosa was observed in hospital effluents.; 93.82% of isolates were multidrug-resistant.; Most of the isolates showed biofilm formation activities.; 19.75% of isolates harbored class 1 integron genes.; Hospital wastewater in Dhaka acts as a reservoir of MDR P. aeruginosa.;

Abstract The study aims to develop an eco-friendly solution for addressing contaminants in hospital wastewater. To achieve this, banana peel, a cost-effective and easily available agricultural waste, was chemically modified using sulfuric acid and sodium hydroxide. The hospital wastewater was analyzed using an Atomic Absorption Spectrometer to identify the presence of heavy metals. The physicochemical properties were measured and compared against the standards set by the World Health Organization (WHO). Scanning electron microscopy and Fourier-transform infrared spectroscopy were used to characterize the chemically modified banana peel. Batch adsorption was conducted with the wastewater using the prepared adsorbent. The effect of contact time, mixing rate, temperature, and adsorbent dosage was examined to know the removal efficiency of the adsorbent. The experimental design incorporates Taguchi OA design to optimize the process. The total heavy metals discovered in the wastewater were As, Cd, Fe, Cu, Ni, Cr, Pb, Mn and Zn. The percentage of Cd, Fe, Cu, Ni, Cr and Pb removed were 79.5%, 87.9%, 56.9%, 89.0%, 88.5% and 93.5%, respectively, at temperature, adsorbent dosage, mixing rate and contact time of 30 °C, 3 g, 700 rpm and 60 min, respectively. The physicochemical properties remain within the acceptable WHO range except the turbidity. At optimum point, the percentage removal of Cd, Fe, Cu, Ni, Cr, Pb and Zn were 64.3%, 80.5%, 51.4%, 82.3%, 72.4%, 86.6% and 72.1%, respectively; while, the conductivity, pH, TDS, and turbidity value were, respectively, 20.57 mS/cm, 6.8, 10.16 mg/l, and 86.31 NTU. Characterization revealed the existence of active functional groups on the adsorbent surface enhancing the hospital wastewater treatment and change in its morphological structure after the treatment was noticed. In conclusion, the modified banana peel was effective for the treatment of hospital wastewater.

This study investigates the removal of amoxicillin micropollutants (AM) from hospital wastewater using CoMoO4-modified graphitic carbon nitride (CMO/gCN). Consequently, CMO/gCN exhibits notable improvements in visible light absorption and electron–hole separation rates compared to unmodified gCN. Besides, CMO/gCN significantly enhances the removal efficiency of AM, attaining an impressive 96.5%, far surpassing the performance of gCN at 48.6%. Moreover, CMO/gCN showcases outstanding reusability, with AM degradation performance exceeding 70% even after undergoing six cycles of reuse. The removal mechanism of AM employing CMO/gCN involves various photoreactions of radicals (•OH, •O2−) and amoxicillin molecules under light assistance. Furthermore, CMO/gCN demonstrates a noteworthy photodegradation efficiency of AM from hospital wastewater, reaching 92.8%, with a near-complete reduction in total organic carbon levels. Detailed discussions on the practical applications of the CMO/gCN photocatalyst for removal of micropollutants from hospital wastewater are provided. These findings underline the considerable potential of CMO/gCN for effectively removing various pollutants in environmental remediation strategies. [ABSTRACT FROM AUTHOR]

This study assessed wastewater treatment by visible-light/Peroxymonosulfate process using its linking with TiO2@Fe3O4 nanoparticles coated on chitosan. Meropenem and Imipenem photodegradation was evaluated as a model-resistant contaminant by TiO2@Fe2O3/chitosan nanocomposite. The synthesised TiO2@Fe2O3/chitosan was characterised using various techniques. Fe2O3 and TiO2 nanoparticles on the chitosan surface were affirmed via XRD, EDX, and FTIR findings. The FESEM and TEM results verified the deposition of TiO2@Fe2O3 on the chitosan surface. Under optimum circumstances (pH = 4, catalyst dosage = 0.5 g/L, antibiotics concentration = 25 mg/L reaction time = 30 min, and PMS = 2 mM), maximum degradation efficiency was obtained at about 95.64 and 93.9% for Meropenem and Imipenem, respectively. Also, the experiments demonstrated that TiO2@Fe2O3/chitosan had a better performance than photolysis and adsorption by catalyst without visible light irradiation in degrading antibiotics. The scavenger tests confirmed that ${\rm O}_2^{\cdot -}$ O 2 ⋅ − , ${\rm SO}_4^{\cdot -}$ SO 4 ⋅ − , ${\rm HO}\cdot$ HO ⋅ , and h+ are present simultaneously during the pollutant photodegradation process. After five recovery cycles, the system eliminated over 80 percent of antibiotics. It suggested that the catalyst's capacity to be reused may be cost-effective. [ABSTRACT FROM AUTHOR]

The extent of removal of pharmaceuticals by African-based wastewater treatment plants (WWTPs) is relatively unknown with various studies observing high concentrations in effluents. This is mainly due to WWTPs still utilising the traditional treatment methods which are known to be less effective. In this study, 15 selected antibiotics (amoxicillin, ampicillin, azithromycin, ciprofloxacin, doxycycline, erythromycin, gentamicin, metronidazole, norfloxacin, ofloxacin, penicillin, sulfamethoxazole, sulfapyridine, tetracycline and trimethoprim) were monitored in wastewater as it goes through sedimentation (primary and secondary), aeration and chlorination stages of a WWTP. Analytical method involved solid-phase extraction followed by liquid chromatographic determination. Removal efficiencies during sedimentation were generally positive with doxycycline achieving 80–95.8%, while negative removal efficiencies were observed for penicillin V (−46.4 to −17.1%) and trimethoprim (−26.2 to −18.9%). The aeration and agitation stage resulted in concentration enhancement for several antibiotics with seven of them ranging between −273 and −15.5%. This stage was responsible for the relatively low overall removal efficiencies in which only 4 antibiotics (doxycycline, tetracycline, ciprofloxacin, and erythromycin) experienced overall removal efficiencies above 50%. The recorded effluent concentrations ranging between 0.0130 and 0.383 ng/mL were translated to low potential for development of antibiotic resistance genes in the receiving environments while ecotoxicity risk was high for only amoxicillin, ampicillin and sulfapyridine. The study has provided an overview of the performance of common wastewater treatment processes in South Africa and hopes that more monitoring and environmental risk data can be made available towards drafting of antibiotic priority lists that cater for Africa. [ABSTRACT FROM AUTHOR]

The study aims to develop an eco-friendly solution for addressing contaminants in hospital wastewater. To achieve this, banana peel, a cost-effective and easily available agricultural waste, was chemically modified using sulfuric acid and sodium hydroxide. The hospital wastewater was analyzed using an Atomic Absorption Spectrometer to identify the presence of heavy metals. The physicochemical properties were measured and compared against the standards set by the World Health Organization (WHO). Scanning electron microscopy and Fourier-transform infrared spectroscopy were used to characterize the chemically modified banana peel. Batch adsorption was conducted with the wastewater using the prepared adsorbent. The effect of contact time, mixing rate, temperature, and adsorbent dosage was examined to know the removal efficiency of the adsorbent. The experimental design incorporates Taguchi OA design to optimize the process. The total heavy metals discovered in the wastewater were As, Cd, Fe, Cu, Ni, Cr, Pb, Mn and Zn. The percentage of Cd, Fe, Cu, Ni, Cr and Pb removed were 79.5%, 87.9%, 56.9%, 89.0%, 88.5% and 93.5%, respectively, at temperature, adsorbent dosage, mixing rate and contact time of 30 °C, 3 g, 700 rpm and 60 min, respectively. The physicochemical properties remain within the acceptable WHO range except the turbidity. At optimum point, the percentage removal of Cd, Fe, Cu, Ni, Cr, Pb and Zn were 64.3%, 80.5%, 51.4%, 82.3%, 72.4%, 86.6% and 72.1%, respectively; while, the conductivity, pH, TDS, and turbidity value were, respectively, 20.57 mS/cm, 6.8, 10.16 mg/l, and 86.31 NTU. Characterization revealed the existence of active functional groups on the adsorbent surface enhancing the hospital wastewater treatment and change in its morphological structure after the treatment was noticed. In conclusion, the modified banana peel was effective for the treatment of hospital wastewater. [ABSTRACT FROM AUTHOR]

Hospital wastewater has been identified as a hotspot for the emergence and transmission of multidrug-resistant (MDR) pathogens that present a serious threat to public health. Therefore, we investigated the current status of antibiotic resistance as well as the phenotypic and genotypic basis of biofilm formation in Pseudomonas aeruginosa from hospital wastewater in Dhaka, Bangladesh. The disc diffusion method and the crystal violet assay were performed to characterize antimicrobial resistance and biofilm formation, respectively. Biofilm and integron-associated genes were amplified by the polymerase chain reaction. Isolates exhibited varying degrees of resistance to different antibiotics, in which .80% of isolates showed sensitivity to meropenem, amikacin, and gentamicin. The results indicated that 93.82% of isolates were MDR and 71 out of 76 MDR isolates showed biofilm formation activities. We observed the high prevalence of biofilm-related genes, in which algDþpelFþpslDþ (82.7%) was found to be the prevalent biofilm genotypic pattern. Sixteen isolates (19.75%) possessed class 1 integron (int1) genes. However, statistical analysis revealed no significant association between biofilm formation and multidrug resistance (χ2 = 0.35, P = 0.55). Taken together, hospital wastewater in Dhaka city may act as a reservoir for MDR and biofilm-forming P. aeruginosa, and therefore, the adequate treatment of wastewater is recommended to reduce the occurrence of outbreaks. [ABSTRACT FROM AUTHOR]

The source and composition of hospital wastewater are complex，including pathogenic microorganisms，chemical drugs and metabolites，heavy metals，contrast agents，resistance genes，etc. When it in a special period of repeated outbreaks of Corona Virus Disease 2019（COVID-19）， the number of patients in the hospital is increasing rapidly，and the corresponding consumed therapeutic drugs，disinfectants，pathogenic microorganisms are increasing significantly. If the hospital wastewater is not effectively treated by cutting off the ways of pathogenic microorganisms and toxic and harmful substances into the environment，the risk caused by effluent would increase rapidly. This paper analyzes the current situation and problems of domestic hospital wastewater treatment，and clarifies the conventional and frontiers technologies on effluent treatment based on the main components and characteristics of hospital wastewater，and combines with the existing policies and technical specifications on hospital wastewater treatment. Finally，some relative countermeasures and constructive suggestions were proposed to provide some technical reference for the hospital wastewater treatment in China.

Introduction: Hospitals are breeding grounds for multidrug-resistant (MDR) bacteria, posing treatment challenges and increasing the risk of spreading "superbugs." This study investigates the prevalence of colistinresistant bacteria, a last-resort antibiotic, in wastewater from tertiary hospitals in Enugu, Nigeria. Methods: Twenty wastewater samples were collected over three months from two tertiary hospitals in Enugu. A standardized protocol by the American Public Health Association (APHA) was followed. Samples were collected aseptically from key drainage points and transported to the lab within 2 hours. Bacteria were isolated using the pour-plate method and characterized by morphological and biochemical tests, including Catalase, Oxidase, and Glucose Fermentation. Antibiotic susceptibility was assessed using Kirby-Bauer disc diffusion, and colistin resistance was confirmed via broth microdilution. Multiplex PCR detected mcr genes indicating plasmid-mediated resistance. Data were analyzed using SPSS version 23 with Chi-Square and ANOVA tests at a significance level of P < 0.05. Results: Gram-negative bacteria were isolated from 63.1% of samples, with Klebsiella spp. being the most prevalent, accounting for 24.6%. Colistin resistance was phenotypically observed in E. coli (83%), Klebsiella spp. (75%), and Pseudomonas aeruginosa (100%). Genotypically, E. coli harbored mcr-1 (17%) and mcr-3 (83%), while all Klebsiella and Pseudomonas isolates carried multiple mcr genes. Additionally, these bacteria showed resistance to multiple antibiotics, including Septrin, Gentamycin, and Ceftriaxone. Conclusion: The significant presence of colistin-resistant bacteria, especially E. coli and Klebsiella, poses a public health concern, potentially leading to treatment failures and spreading resistance genes. Stricter monitoring of hospital wastewater is necessary to identify emerging resistance trends and improve antibiotic practices in hospitals. [ABSTRACT FROM AUTHOR]

Hospitals discharge large amounts of pathogenic microbes into municipal wastewater and aquatic environments, posing significant challenges in terms of human health and ecological impacts. It is crucial to develop and implement effective techniques for managing and treating such wastewater. In this study, we aimed to design a potential strategy for the treatment of microbial hospital wastewater (HWW) by utilizing a combination of cold plasma (CP) and silver nanoparticles (Ag NPs). Melia azedarach (M. azedarach) leaf extract was used for the biosynthesis of Ag NPs by the green method. Various techniques were employed for Ag NPs characterization. The results obtained from the ultra-violet visible (UV–vis) spectroscopy showed ab absorbance peak at 430 nm. The scanning electron microscope (SEM) images revealed that the biosynthesized Ag NPs appeared spherical with an average size of 13.6 nm. X-ray diffraction (XRD) analysis determined the formation of Ag NPs. Fourier-transform infrared spectroscopy (FTIR) indicated the involvement of biomolecules in the reduction and stabilization of the Ag NPs. For the treatment of HWW, the antibacterial activity of Ag NPs was evaluated at the highest concentration (1:1), while CP was tested at the longest duration of exposure (60 s). The results showed a significant reduction in the average number of bacterial colonies to 18 and 5 colonies, respectively, compared to the control sample (without treatment), which had an average of 175 colonies. Moreover, the combined treatment of Ag NPs and CP resulted in complete inhibition of bacterial growth, with an average number of zero colonies for all samples and treatment conditions. Based on these findings, we believe that the synergistic effect between Ag NPs and CP holds promise as an advanced treatment technology for the elimination of microbes from HWW. This technology has the potential to contribute to a more sustainable and environmentally responsible healthcare system. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) has emerged and spread globally. Recent studies have also reported the presence of antimicrobials in a wide variety of aquatic environments. Conducting a nationwide monitoring survey of AMR in the environment to elucidate its status and to assess its impact on ecosystems and human health is of social importance. In this study, we developed a novel high-throughput analysis (HTA) system based on a 96-well plate solid-phase extraction (SPE), using automated pipetting and an SPE pre-treatment system. The effectiveness of the system as an HTA for antimicrobials in environmental water was verified by comparing it with a conventional manual analytical system in a domestic hospital over a period of two years and four months. The results of the manual analysis and HTA using a combination of automated pipetting and SPE systems were generally consistent, and no statistically significant difference was observed (p > 0.05) between the two systems. The agreement ratios between the measured concentrations based on the conventional and HTA methods were positively correlated with a correlation coefficient of r = 0.99. These results indicate that HTA, which combines automated pipetting and an SPE pre-treatment system for rapid, high-volume analysis, can be used as an effective approach for understanding the environmental contamination of antimicrobials at multiple sites. To the best of our knowledge, this is the first report to present the accuracy and agreement between concentrations based on a manual analysis and those measured using HTA in hospital wastewater. These findings contribute to a comprehensive understanding of antimicrobials in aquatic environments and assess the ecological and human health risks associated with antimicrobials and antimicrobial-resistant bacteria to maintain the safety of aquatic environments. [ABSTRACT FROM AUTHOR]

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract The One Health concept recognizes that human health is clearly linked to the health of animals and the environment. Infections caused by bacteria resistant to carbapenem antibiotics have become a major challenge in hospitals due to limited therapeutic options and consequent increase in mortality. In this study, we investigated the presence of carbapenem-resistant Enterobacteriaceae in 84 effluent samples (42 from hospital and 42 from non-hospital) from Campo Grande, midwest Brazil. First, sewage samples were inoculated in a selective culture medium. Bacteria with reduced susceptibility to meropenem and ertapenem were then identified and their antimicrobial susceptibility was determined using the Vitek-2 system. The blaKPC genes were detected using PCR and further confirmed by sequencing. Carbapenem-resistant Enterobacteriaceae (CRE) were identified in both hospital (n=32) and non-hospital effluent (n=16), with the most common being Klebsiella pneumoniae and of the Enterobacter cloacae complex species. This is the first study to indicate the presence of the blaKPC-2 gene in carbapenem-resistant Enterobacteriaceae, classified as a critical priority by the WHO, in hospital sewage in this region. The dissemination of carbapenem antibiotic-resistant genes may be associated with clinical pathogens. Under favorable conditions and microbial loads, resistant bacteria and antimicrobial-resistance genes found in hospital sewage can disseminate into the environment, causing health problems. Therefore, sewage treatment regulations should be implemented to minimize the transfer of antimicrobial resistance from hospitals.

Steroid hormones, classified as endocrine-disrupting compounds (EDCs), pose significant environmental and health concerns due to their persistence and potential adverse effects. This study investigates the presence of estrone (E1) in hospital wastewater and the efficiency of E1 removal through a photocatalytic membrane reactor (PMR). Wastewater samples were collected from two hospitals with different wastewater treatment processes. The concentration of E1 was analyzed using a combination of solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The PMR experimental setup involved a polyvinylidene fluoride (PVDF) membrane incorporated with 1 wt% titanium dioxide (PVDF/TiO2). The PMR performance was evaluated with and without UVC radiation. The membranes were characterized for their water contact angle (WCA) and surface morphology. The maximum concentration of E1 in the hospital wastewater was 2.46 ± 1.90 ng L-1. The PMR, operated for 180 min, demonstrated that PVDF/TiO2 (UV) exhibited the highest E1 removal efficiency (96.7 ± 1.4%). This superior performance was attributed to the synergistic effect of PVDF/TiO2 membrane filtration combined with UV irradiation, enhancing the removal capacity. The removal of E1 in the PVDF/TiO2 membrane (36.5 ± 2.7%) surpassed that of the PVDF membrane (32.6 ± 7.8%). The kinetics analysis indicated that the degradation of E1 followed pseudo first-order kinetics. These findings underscore the potential of PMR technology, specifically employing PVDF/TiO2 membranes with UV irradiation, for efficient removal of E1 from hospital wastewater, offering insights for future applications in mitigating micropollutant release into the environment.

Background: Water contamination by synthetic organic chemicals like antibiotics is a major environmental issue. Tetracycline (TC), an antibiotic in a wide family, is notable. A moving bed sequenced batch reactor (MBSBR) is tested for treating hospital raw wastewater containing TC.Methods: A 35-L pilot system was constructed, with 30 L usable. PVC suspended carriers (Kaldnes K3) with 584.3 m2/m3 specific surface area made about 70% of the functional volume. The independent variables in this study were hydraulic retention duration (1, 1.5, 2, and 2.5 hours) and starting TC concentration (5, 10, and 15 mg/L).Results: The findings of the study demonstrated satisfactory performance under the conditions of an initial TC concentration of 5 mg/L and an organic load of 350 mg/L. The overall removal efficiencies for TC, chemical oxygen demand (COD), and biological oxygen demand (BOD5) were 72.8%, 83%, and 93.9%, respectively. The optimal performance of the system was primarily observed during the initial phase, characterized by a TC concentration of 5 mg/L and a hydraulic retention time (HRT) of 2.5 hours. The experimental results also indicated that the maximum removal efficiency was 1.8 kg COD/m2.day, as determined by a fitted surface loading rate (SLR). Furthermore, the food-tomicroorganism (F/M) ratio decreased from 0.101 to 0.038 as the HRT increased from 1 to 2.5 hours.Conclusion: The results of the study indicate that the MBSBR exhibits a high level of efficiency in removing TC from hospital wastewater.

Abstract Ozone micron bubble (OMB) treatment offers a promising approach to effectively eliminate Antibiotic Resistance Genes (ARGs) from infectious medical wastewater and mitigate the threat of drug resistance transmission. This study evaluated the effectiveness of OMB treatment for reducing ARGs from infectious medical wastewater in laboratory and on-site pilot treatment setups. In part, the presence of antibiotic residues in a hospital wastewater treatment plant (WWTP) and the impact of hospital wastewater on the distribution of ARGs in a wastewater collection system were also investigated. The results of wastewater collection system survey revealed a high prevalence of ARGs in the system, particularly mcr-1, largely originating from medical wastewater discharges. Furthermore, analysis of antibiotic residues in the hospital wastewater treatment system showed significant accumulation, particularly of quinolone antibiotics, in the biomass of the biological oxidation tank, suggesting a potential risk of ARG proliferation within the system. Comparison of wastewater samples from domestic and hospital WWTPs revealed a relatively higher abundance of ARGs in the latter, with differences ranging from 2.2 to sixfold between corresponding locations in the treatment plants. Notably, the biological oxidation unit of both WWTPs exhibited a greater proportion of ARGs among all sampled points, indicating the potential proliferation of ARGs within the biomass of the treatment units. ARG degradation experiments showed that OMB treatment resulted in a significantly lower CT value (9.3 mg O3 L−1 min) compared to ozone coarse bubble treatment (102 mg O3 L−1 min) under identical test conditions. Moreover, the use of OMB on site significantly reduced the accumulation of ARGs in hospital wastewater, underscoring its potential as an effective solution for mitigating ARG spread.

Abstract Background Extended-spectrum β-lactamase (ESBL), plasmid-mediated AmpC-β-lactamase and carbapenemase-producing Escherichia coli and Klebsiella pneumoniae have spread into the environment worldwide posing a potential public health threat. However, the prevalence data for low- and middle-income countries are still scarce. The aim of this study was to evaluate the presence of ESBL, AmpC-β-lactamase and carbapenemase-producing and multidrug-resistant E. coli and K. pneumoniae in wastewaters from healthcare centers in Burkina Faso. Results Eighty-four (84) wastewater samples were collected from five healthcare centers and plated on selective ESBL ChromAgar. E. coli and Klebsiella pneumoniae isolates were identified using API20E. ESBL-producing bacteria were detected in 97.6% of the samples and their average concentration per hospital ranged from 1.10 × 105 to 5.23 × 106 CFU/mL. Out of 170 putative ESBL-producing isolates (64% of them were E. coli) and 51 putative AmpC-β-lactamase-producing isolates, 95% and 45% were confirmed, respectively. Carbapenemase production was detected in 10 isolates, of which 6 were NDM producers, 3 were OXA-48 producers and 1 was NDM and OXA-48 producer. All isolates were multidrug resistant and, moreover, all of them were resistant to all tested β-lactams. Resistance to ESBL inhibitors was also common, up to 66% in E. coli and 62% in K. pneumoniae. Amikacin, fosfomycin and nitrofurantoin were the antibiotics to which the least resistance was detected. Conclusions This study showed that wastewater from healthcare centers constitutes a reservoir of multidrug-resistant bacteria in Burkina Faso, including carbapenemase producers. Untreated healthcare wastewater entering the environment exposes people and animals to infections caused by these multi-resistant bacteria, which are difficult to treat, especially in the resource-poor settings.

In this study a dispersive liquid-liquid micro-extraction (DLLME) method was utilized for extraction of trace pharmaceuticals in wastewater samples. Factors influencing the extraction performances were tested and accordingly 900 μL dichloroethane as the extraction solvent, 1400 μL acetonitirle as dispersive solvent, 10 min extraction time at 4000 rpm centrifugation, and pH 5 were found optimum. Acetonitrile and 0.2% formic acid in water were used as eluent. The column temperature was maintained at 25 °C and the optimum detection wavelengths of 273 nm for sulfamethoxazole and 280 nm for ciprofloxacin were used. For both the analytes, the coefficients of determinations (r2) were found to vary from 0.9989 to 0.9997, confirming good linearity in the concentration range of 0.005-100 μg mL-1 for sulfamethoxazole and 0.01-100 μg mL-1 for ciprofloxacin. The LOD and LOQ were in the range of 0.78-1.58 ng mL-1 and 2.24-5.28 ng mL-1, respectively; the RSDs were 0.41-3.21% for intra-day precision and 0.37-6.44% for inter-day precision. The concentrations of the three pharmaceuticals determined ranged from 0.76-1.53 μg mL-1 in the wastewater samples collected from Black Lion Hospital. However, ciprofloxacin and doxycycline were not detected and only low concentration of sulfamethoxazole was detected in the wastewater samples collected from Menelik II Hospital. [ABSTRACT FROM AUTHOR]

This study employed simple polystyrene-coated magnetite nanoparticles (PS@MNPs)–assisted batch adsorption process for the removal of two antidepressant active ingredients (amitriptyline HCl and sertraline HCl) from hospital wastewater. Dominant parameters of the adsorption process including pH, adsorbent amount, and contact period were optimized through the univariate approach to enhance the adsorption efficiency. Upon reaching optimum adsorption conditions, equilibrium experiments were performed by spiking the adsorbates in hospital wastewater in the concentration range of 100–2000 μg/L. The concentrations of the adsorbates in the effluent were calculated using the matrix-matching calibration strategy to enhance the accuracy of quantification. A validated switchable solvent-based liquid phase microextraction (SS-LPME) method was employed to enrich the two active pharmaceutical ingredients (APIs) prior to sensitive determination with GC-MS (gas chromatography-mass spectrometry). The equilibrium data were mathematically modeled employing the Langmuir and Freundlich adsorption isotherm models. The isotherm constants were calculated, and the results showed that both the isotherm models fitted well with the experimental data. The efficient and simple batch adsorption strategy reported in this study was successfully employed to remove amitriptyline HCl and sertraline HCl from hospital wastewater at low concentrations. [ABSTRACT FROM AUTHOR]

With the advent of technologies in many countries, pharmaceutically active compounds (PhAC), personal care products (PPCPs), and other medicines have been treated by particular facilities. Although the overall rate of PhACs extraction from hospital wastewater (HWW) through different secondary wastewater treatment plants (WWTPs) has been high equal to 79–99%, activity and proliferation of neurotransmitters are inhibited by antiseptics due to the low removal rate of some elements, such as naproxen, excellent-performance technologies are still needed. Venlafaxine and citalopram are the most used antidepressants associated with 10–12% removal value through WWTPs. While HWW contains various types of antibiotics, they improve biocides' bacterial tolerance against treatment. Ozonation is one of the methods to enhance biodegradability, whereas biofilm reactors have effectively removed emerging contaminants (ECs). Combined activate sludge (CAS) and membrane filtration bioreactors will potently exclude compounds, but previous studies show that membrane filtration bioreactors are around 30%-55% more efficient. ECs elimination in tertiary treatment has shown its great ability rather than conventional treatment sectors. Moreover, ozone treatment can decrease in PPCPs value as 90–98% through activated carbon beds. Activated carbon (NAC) has shown its full capability for micropollutants removal from PAC and membrane bioreactors as well as PPCP reside removal from treated effluents. The ratio of infect COVID-19 in one area was directly proportional, as revealed by SARS-CoV-2 detection in both HWW and wastewater in almost all countries. In this research study, multiple treatment techniques are evaluated in order to offer great-performance technology. [ABSTRACT FROM AUTHOR]

Large amounts of antibiotics have been discharged into wastewater during the COVID-19 pandemic due to overuse and misuse of antibiotics to treat patients. Wastewater-based surveillance can be used as an early warning for antibiotic resistance (AR) emergence. The present study analyzed municipal wastewater corresponding to the major pandemic waves (WW1, WW2, and WW3) in India along with hospital wastewater (Ho) taken as a benchmark for AR. Commonly prescribed antibiotics during a pandemic, azithromycin and cefixime residues, were found in the range of 2.1–2.6 μg/L in Ho and WW2. Total residual antibiotic concentration was less in WW2; however, the total antibiotic resistance gene (ARG) count was 1065.6 ppm compared to 85.2 ppm in Ho. Metagenome and RT-qPCR analysis indicated a positive correlation between antibiotics and non-corresponding ARGs (blaOXA, aadA, cat, aph3, and ere), where 7.2–7.5% was carried by plasmid in the bacterial community of WW1 and WW2. Moreover, as the abundance of the dfrA and int1 genes varied most among municipal wastewater, they can be suggested as AR markers for the pandemic. The common pathogens Streptococcus, Escherichia, Shigella, and Aeromonas were putative ARG hosts in metagenome-assembled genomes. The ARG profile and antibiotic levels varied between municipal wastewaters but were fairly similar for WW2 and Ho, suggesting the impact of the pandemic in shaping the resistome pattern. The study provides insights into the resistome dynamic, AR markers, and host-ARG association in wastewater during the COVID-19 surge. Continued surveillance and identification of intervention points for AR beyond the pandemic are essential to curbing the environmental spread of ARGs in the near future. [ABSTRACT FROM AUTHOR]

This study assessed different regression models to estimate the concentration that inhibits 50% of Allium cepa root growth after exposure to different concentrations (5 to 100%v/v) of hospital wastewater for 72 h. In addition, the mitotic index was also calculated. The results indicate alterations in the normal development of A. cepa owing to the possible presence of toxic substances, identifying a maximum root inhibition of 61.01% and a minimum mitotic index of 2.15%. The Gompertz model was better than other models for its adequate adjustment and low error with a half maximal inhibitory concentration of 57.5% (moderately toxic waters) and a difference of 23% with traditional models such as Probit (80%) or Log-Logistic (80%). Toxicity tests with bioluminescent bacteria (Vibrio fischeri) confirmed the results obtained from A. cepa bioassays. [ABSTRACT FROM AUTHOR]

Ozone micron bubble (OMB) treatment offers a promising approach to effectively eliminate Antibiotic Resistance Genes (ARGs) from infectious medical wastewater and mitigate the threat of drug resistance transmission. This study evaluated the effectiveness of OMB treatment for reducing ARGs from infectious medical wastewater in laboratory and on-site pilot treatment setups. In part, the presence of antibiotic residues in a hospital wastewater treatment plant (WWTP) and the impact of hospital wastewater on the distribution of ARGs in a wastewater collection system were also investigated. The results of wastewater collection system survey revealed a high prevalence of ARGs in the system, particularly mcr-1, largely originating from medical wastewater discharges. Furthermore, analysis of antibiotic residues in the hospital wastewater treatment system showed significant accumulation, particularly of quinolone antibiotics, in the biomass of the biological oxidation tank, suggesting a potential risk of ARG proliferation within the system. Comparison of wastewater samples from domestic and hospital WWTPs revealed a relatively higher abundance of ARGs in the latter, with differences ranging from 2.2 to sixfold between corresponding locations in the treatment plants. Notably, the biological oxidation unit of both WWTPs exhibited a greater proportion of ARGs among all sampled points, indicating the potential proliferation of ARGs within the biomass of the treatment units. ARG degradation experiments showed that OMB treatment resulted in a significantly lower CT value (9.3 mg O3 L−1 min) compared to ozone coarse bubble treatment (102 mg O3 L−1 min) under identical test conditions. Moreover, the use of OMB on site significantly reduced the accumulation of ARGs in hospital wastewater, underscoring its potential as an effective solution for mitigating ARG spread. [ABSTRACT FROM AUTHOR]

Background: Extended-spectrum β-lactamase (ESBL), plasmid-mediated AmpC-β-lactamase and carbapenemase-producing Escherichia coli and Klebsiella pneumoniae have spread into the environment worldwide posing a potential public health threat. However, the prevalence data for low- and middle-income countries are still scarce. The aim of this study was to evaluate the presence of ESBL, AmpC-β-lactamase and carbapenemase-producing and multidrug-resistant E. coli and K. pneumoniae in wastewaters from healthcare centers in Burkina Faso. Results: Eighty-four (84) wastewater samples were collected from five healthcare centers and plated on selective ESBL ChromAgar. E. coli and Klebsiella pneumoniae isolates were identified using API20E. ESBL-producing bacteria were detected in 97.6% of the samples and their average concentration per hospital ranged from 1.10 × 105 to 5.23 × 106 CFU/mL. Out of 170 putative ESBL-producing isolates (64% of them were E. coli) and 51 putative AmpC-β-lactamase-producing isolates, 95% and 45% were confirmed, respectively. Carbapenemase production was detected in 10 isolates, of which 6 were NDM producers, 3 were OXA-48 producers and 1 was NDM and OXA-48 producer. All isolates were multidrug resistant and, moreover, all of them were resistant to all tested β-lactams. Resistance to ESBL inhibitors was also common, up to 66% in E. coli and 62% in K. pneumoniae. Amikacin, fosfomycin and nitrofurantoin were the antibiotics to which the least resistance was detected. Conclusions: This study showed that wastewater from healthcare centers constitutes a reservoir of multidrug-resistant bacteria in Burkina Faso, including carbapenemase producers. Untreated healthcare wastewater entering the environment exposes people and animals to infections caused by these multi-resistant bacteria, which are difficult to treat, especially in the resource-poor settings. [ABSTRACT FROM AUTHOR]

Binary zinc oxide (ZnO) nanocomposites with different noble metals, silver (Ag) and ruthenium (Ru), were prepared from an aqueous leaf extract of Callistemon viminalis. The biosynthesized photocatalysts were characterized and examined for their photocatalytic disinfection against Escherichia coli isolated from hospital wastewater. The influence of the different noble metals showed a difference in physicochemical characteristics and photocatalytic efficiency between Ag–ZnO and Ru–ZnO. The photocatalytic degradation of methylene blue and photocatalytic disinfection were found to be in the order Ag–ZnO > Ru–ZnO > ZnO. The photocatalytic disinfection of Ag–ZnO reached a 75% reduction in 60 min, compared to 34 and 9% reductions of Ru–ZnO and ZnO, respectively. The kinetic reaction rate for the photocatalytic disinfection of Ag–ZnO was found to be 2.8 times higher than that of Ru–ZnO. The outstanding photocatalytic activity of Ag–ZnO over Ru–ZnO was attributed to higher crystallinity, greater UVA adsorption capacity, smaller particle size, and the additional antimicrobial effect of Ag itself. The C. viminalis-mediated Ag–ZnO nanocomposites can be a potential candidate for photocatalytic disinfection of drug-resistant E. coli in hospital wastewater. HIGHLIGHTS Biosynthesis and characterization of two zinc oxide-based nanocomposites with silver and ruthenium were presented.; Photocatalytic disinfection of Escherichia coli present in hospital wastewater was demonstrated.; The influence of different noble metals (silver and ruthenium) on the characteristics and photocatalytic efficiency were discussed.;

Hospital wastewater can contaminate the environment with antibiotic-resistant and virulent bacteria. We analyzed wastewater samples from four hospitals in Ardabil province, Iran for Enterococcus faecium and Enterococcus faecalis using culture and molecular methods. We also performed antimicrobial susceptibility testing and polymerase chain reaction testing for resistance and virulence genes. Out of 141 enterococci isolates, 68.8% were E. faecium and 23.4% were E. faecalis. Ciprofloxacin and rifampicin showed the highest level of resistance against E. faecalis and E. faecium isolates at 65%. High-level gentamicin resistance (HLGR), high-level streptomycin resistance (HLSR), ampicillin, and vancomycin resistance were observed in 25, 5, 10, and 5.15% of E. faecium, and 15, 6, 15, and 3.03% of E. faecalis isolates, respectively. The ant(6′)-Ia and ant(3′)-Ia genes that were responsible for streptomycin resistance were observed in HLSR isolates and aph(3′)-IIIa and aac(6′) Ie-aph(2″)-Ia genes accounting for gentamicin resistance were detected in HLGR isolates. vanA was the predominant gene detected in vancomycin-resistant isolates. The majority of isolates were positive for gelE, asa1, esp, cylA, and hyl virulence genes. We found that drug-resistant and virulent E. faecalis and E. faecium isolates were prevalent in hospital wastewater. Proper treatment strategies are required to prevent their dissemination into the environment. HIGHLIGHTS The prevalence of E. faecium isolates in hospital wastewater was three times higher than that of E. faecalis isolates.; Five percent of E. faecium and 3% of E. faecalis isolates were vancomycin-resistant.; The rate of HLSR was almost four times the rate of HLGR among Enterococcus spp.; Almost all of the isolates were multidrug-resistant.; The majority of E. faecalis and E. faecium isolates contained multiple virulence genes simultaneously.;

Antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in treated hospital wastewater effluents constitute a major environmental and public health concern. The aim of this study was to investigate the antibiotic resistance patterns of Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa isolated from wastewater effluent at the Benjamin Mkapa Hospital (BMH) in Dodoma, Tanzania. These bacteria were selected to represent the most prevalent gram-negative bacteria found in hospital wastewater, and they have the potential to generate resistance and spread resistance genes to antibiotics. The wastewater BMH is treated in a Constructed Wetland (CW) planted with Typha latifolia before being released into the environment. The bacteria were isolated from wastewater effluent collected at the outlet of the CW. Isolated bacteria were analyzed for antibiotic resistance by disc diffusion method. Molecular identification of bacterial species was performed by using 16S rRNA. The results show that Klebsiella ssp. was the most common isolate detected, with a prevalence of 39.3%, followed by E. coli (27.9%) and Pseudomonas ssp. (18.0%). Klebsiella ssp. were more resistant than Pseudomonas ssp. for Tetracycline, Gentamycin, Ciprofloxacin, and Sulfamethoxazole. Pseudomonas ssp. were more resistant than Klebsiella ssp. for Ceftriaxone and Azithromycin. Klebsiella ssp. harbored more resistance genes (40%), followed by Pseudomonas ssp. (35%) and E. coli (20%). The findings of this investigation indicate that the effluent from the CW requires additional treatment to reduce discharged ARB and ARGs in the receiving water bodies. As a result, the effluent quality of the CW should be continuously monitored and assessed, and further developments for treating the final effluent are necessary.

Background: Worldwide observations revealed increased frequencies of multi-resistant Enterobacterales and resistance genes in hospital wastewater compared to any other type of wastewater. Despite the description of clonal lineages possibly adapted to hospital wastewater, little is known about long term persistence as well as evolution of these lineages. Methods: In this study, wastewater isolates of different Enterobacterales species from a tertiary care hospital were investigated with 2.5 years distance. Whole Genome Sequencing (WGS) and resistance gene identification were performed for E. coli, C. freundii, S. marcescens, K. pneumoniae, K. oxytoca, and E. cloacae isolates (n = 59), isolated in 2022 and compared with strains isolated from the same wastewater pipeline in 2019 (n = 240). Results: Individual clonal lineages with highly related isolates could be identified in all species identified more than once in 2022 that appear to persist in the wastewater drainage. A common motif of all persistent clonal lineages was the carriage of mobile genetic elements encoding carbapenemase genes with hints for horizontal gene transfer in persistent clones in this environment observed over the 2.5-year period. Multiple plasmid replicons could be detected in both years. In 2022 isolates blaVIM-1 replaced blaOXA-48 as the most common carbapenemase gene compared to 2019. Interestingly, despite a similar abundance of carbapenemase genes (>80% of all isolates) at both time points genes encoding extended spectrum β-lactamases decreased over time. Conclusions: This data indicates that hospital wastewater continuously releases genes encoding carbapenemases to the urban wastewater system. The evolution of the resident clones as well as the reasons for the selection advantage in this specific ecological niche needs to be further investigated in the future.

The problem of antimicrobial resistance (AMR) is not limited to the medical field but is also becoming prevalent on a global scale in the environmental field. Environmental water pollution caused by the discharge of wastewater into aquatic environments has caused concern in the context of the sustainable development of modern society. However, there have been few studies focused on the treatment of hospital wastewater, and the potential consequences of this remain unknown. This study evaluated the efficacy of the inactivation of antimicrobial-resistant bacteria (AMRB) and antimicrobial resistance genes (AMRGs) in model wastewater treatment plant (WWTP) wastewater and hospital effluent based on direct ultraviolet (UV) light irradiation provided by a conventional mercury lamp with a peak wavelength of 254 nm and an ultraviolet light-emitting diode (UV-LED) with a peak emission of 280 nm under test conditions in which the irradiance of both was adjusted to the same intensity. The overall results indicated that both UV- and UV-LED-mediated disinfection effectively inactivated the AMRB in both wastewater types (>99.9% after 1–3 min of UV and 3 min of UV-LED treatment). Additionally, AMRGs were also removed (0.2–1.4 log10 for UV 254 nm and 0.1–1.3 log10 for UV 280 nm), and notably, there was no statistically significant decrease (p < 0.05) in the AMRGs between the UV and UV-LED treatments. The results of this study highlight the importance of utilizing a local inactivation treatment directly for wastewater generated by a hospital prior to its flow into a WWTP as sewage. Although additional disinfection treatment at the WWTP is likely necessary to remove the entire quantity of AMRB and AMRGs, the present study contributes to a significant reduction in the loads of WWTP and urgent prevention of the spread of infectious diseases, thus alleviating the potential threat to the environment and human health risks associated with AMR problems.

The waste of multiple residually harmful hospital pharmaceutical materials such as antibiotics, chemicals, hormonal waste, and residual particles from different types of medicine used in anticonvulsants and antipyretics is one of the most serious health issues confronting health workers today. During the past decades, many efforts were made to remove the effects of this environmental pollution. Efficient, stable, fast, and environmentally friendly methods use nanoparticles such as nanomaterials, carbon nanotubes, and nanofilters to reduce the toxicity and side effects of the waste even if they are present at a low concentration. This review describes the use of the nanomaterials, the effects of their concentration, the investigation of their application, and the effectiveness on hospital waste removal.

Background and objectives: Water pollution from sewage has become a subject of considerable public and scientific concern, given its demonstrated extreme toxicity to human health and biological ecosystems. Hospital wastewater poses a serious health risk to staff, the public, and the environment. This study was conducted to determine the physical, chemical and biological parameters of hospital wastewater from Mohammed VI University Hospital in Marrakech, which is discharged into the municipal sewage system, where it mixes with sewage from urban areas without prior treatment. Methods: This study was conducted between October 2022 and January 2023 with a sampling frequency of 15 days each. Hospital wastewater samples were collected at the main collector of all manholes in the hospital. Findings: Physicochemical characterization of the effluents from each department showed that they are heavily polluted with organic matter, with average values in the range of 750 mg/L COD, 512.14 mg/L BOD5 and 879.86 mg /L TSS. These values are higher than those recommended in the Moroccan discharge standards. Total phosphorus, sulfates, nitrates and nitrites are 5.92 mg/L, 427.97 mg/L, 7.39 mg/L and 0.60 mg/L, respectively. Bacteriological characterization shows that fecal coliform bacteria reach 12 x 106 CFU/100 mL. These effluents also contain pathogens responsible for nosocomial infections, especially Staphylococcus aureus. The ratio COD / BOD5 is about 1.46, a value indicating that hospital wastewater is readily biodegradable. Conclusion: Therefore, proper treatment of these hospital effluents is essential due to their physicochemical and pathogenic bacterial load, which can negatively affect public health and carry the risk of spreading epidemic diseases.

ABSTRACT Carbapenem-resistant Acinetobacter baumannii spp. are increasingly important pathogens with limited treatment options, and there is limited knowledge on the environmental factors contributing to their spread. We determined the occurrence of carbapenem-resistant A. baumannii in hospital wastewater and their phylogenetic relationships with clinical A. baumannii isolates. Grab samples of raw and treated hospital wastewater were collected monthly at the University College Hospital, Ibadan, Nigeria, between March 2021 and February 2022. Acinetobacter baumannii strains were selectively isolated and identified using VITEK2, and their whole genomes were sequenced on an Illumina platform. We performed antimicrobial susceptibility testing and in silico genomic characterization of the strains and determined their phylogenetic relationships to previously characterized clinical A. baumannii strains from Nigeria. A. baumannii complex isolates were recovered from wastewater throughout the study. Of the 82 isolates identified based on whole-genome sequences, 77 were A. baumannii. A. baumannii isolates had high resistance rates (≥48.1%) to 10 of 12 antimicrobials tested, and majority (42/77, 54.5%) were resistant to carbapenems, with bla NDM-1 being the most common (24/77, 31.2%) carbapenem resistance gene detected, followed by bla OXA-23 (n = 22, 28.6%). There was no statistically significant difference in carbapenem resistance rates or carbapenem gene carriage between the raw and treated wastewater isolates. Most of the isolates belonged to novel or sparsely described lineages, some of which were closely related to clinical isolates. The release of inadequately treated hospital wastewater into the environment may contribute to the increased spread of carbapenem-resistant and clinically important A. baumannii lineages in Ibadan, Nigeria. IMPORTANCE Acinetobacter baumannii is a leading cause of hospital-associated infections globally. A. baumannii reservoirs outside hospital settings are still unknown, and their occurrence in the environment is linked to clinical and anthropogenic activities. Although the risk of transmission of A. baumannii from environmental sources to humans is not fully understood, these sources pose significant risks for the continued dissemination of A. baumannii and their resistance traits. This study provides evidence that diverse and clinically relevant A. baumannii strains, many of which are resistant to carbapenems, are constantly being discharged into the environment through inadequately treated hospital wastewater. We further elucidate potential transmission routes between the environment and clinical infections and demonstrate the high prevalence of carbapenem resistance genes on highly mobile transposons among these strains. Our findings highlight the pressing need to address hospital wastewater as a crucial factor in curtailing the spread of carbapenem-resistant A. baumannii.

The present study investigates the viability of using four processes namely; Fenton, Sono-Fenton (SF), Electro-Fenton (EF), and sono-electro-Fenton (SEF) to reduce COD from hospital wastewater. Response surface methodology (RSM) was used to analyze the impact of several operational factors on COD reduction. The optimum circumstances for the Fenton technique were Fe2+ of 1.998 mM, H2O2 of 21.572 mM, pH = 3.2, and 97.029 min, in which COD REF% was 95.13, 90.96% turbidity removal, and 91.67% phenol removal. The concentrations of ferrous ions and hydrogen peroxide were found to be the main factors controlling the Fenton technique's efficacy, with a 75.83% contribution and 10.35%, respectively. The optimum circumstances for the EF technique were FeSO4 of 0.7 mM, a current density of 20 mA/cm2, and 56.36 min, in which COD REEF% was 97.055, 91.35% turbidity removal, 95.56% phenol removal, and specific energy consumption was 12.926 kWh/kg. In Electro-Fenton technique concentration of FeSO4 and the current density are the two most important factors in COD-reducing efficacy, with a 52.48% contribution and 24.97%, respectively. The SF's best results were achieved with 10 mM H2O2, 0.8 mM Fe2+, 97.029 min at pH = 4, and 100 W of US power giving a COD reduction rate of 92.19%, 83.65% turbidity reduction, and 86.11% phenol reduction. For SEF, a COD removal rate of 91.04%, 84.62% turbidity removal, and 91.67% phenol removal were achieved at an SEC of 4.3 kWh/kg COD using FeSO4 concentration of 0.2 mM, current density of 10 mA/cm2, time of 56.36 min, and US power of 100 Watts. Compared to using only the Fenton and EF techniques, the COD reduction is significantly enhanced when the US, combined with the above techniques, is applied at two distinct levels of power (50 and 100 Watts). SEF was found to be the best performance among other in terms of lower SEC required, lower Fe2+ consumption and lower time for operation. The findings contribute to advancing wastewater treatment technologies and provide valuable insights for the implementation of SEF process in the treatment of hospital wastewater, leading to improved environmental and health outcomes and overcoming the drawbacks of traditional methods specifically sludge generation.

In this work, the synthesis of Iron (Fe) and Copper (Cu) co-doped g-C3N4 was performed using the thermal decomposition of urea while iron nitrate and copper nitrate were used as dopant precursors. The fabricated catalyst (Fe-Cu@g-C3N4) was coupled with visible light and used for acetaminophen (APAP) degradation. The synthesized catalyst was characterized via several techniques including XRD, BET, BJH, SEM, TEM, EDX, EDS Dot mapping, DLS, and UV–Vis deflective reflectance spectroscopy. The performed characterization tests confirmed the successful synthesis of Fe-Cu co-doped g-C3N4 with high purity, nano-sheet structure and high porosity (79.93 m2/g). The complete APAP decomposition efficiency was achieved under optimal experimental conditions including pH of 11, catalyst dosage of 10 mg/L, PS dosage of 1 mM, and APAP concentration of 4 mg/L. The scavenging tests confirmed the major contribution of sulfate radicals and consequently, hydroxyl radicals for APAP removal. In addition, the kinetics of APAP degradation was studied and it revealed the pseudo first–order kinetics with 0.0698 min−1 rate constant. Finally, a plausible and tentative decomposition pathway was proposed for APAP degradation. The results of this study confirmed that the LED/catalyst (Cu, Fe@g-C3N4)/PS process could be an efficient and robust process for antibiotic-containing wastewater including hospital wastewater.

To understand which type of hospital waste may contain the highest amount of antibiotic resistant microorganisms that could be released into the environment, the bacterial strains entering and leaving a hospital wastewater treatment plant (HWTP) were identified and tested for their antibiotic susceptibility. To achieve this goal, samples were collected from three separate sites, inlet and outlet wastewater positions, and sludge generated in a septic tank. After microbiological characterization according to APHA, AWWA, and WEF protocols, the relative susceptibility of the bacterial strains to various antibiotic agents was assessed according to the Clinical and Laboratory Standards Institute guidelines, to determine whether there were higher numbers of resistant bacterial strains in the inlet wastewater sample than in the outlet wastewater and sludge samples. The results showed more antibiotic resistant bacteria in the sludge than in the inlet wastewater, and that the Enterobacteriaceae family was the predominant species in the collected samples. The most antibiotic-resistant families were found to be Streptococcacea and non-Enterobacteriaceae. Some bacterial strains were resistant to all the tested antibiotics. We conclude that the studied HWTP can be considered a source of resistant bacterial strains. It is suggested that outlet water and sludge generated in HWTPs should be monitored, and that efficient treatment to eliminate all bacteria from the different types of hospital waste released into the environment is adopted. [ABSTRACT FROM AUTHOR]

This study investigated the efficiency of two advanced oxidation processes (AOPs), ozonation (O3), and electrochemical oxidation (EO), applied individually or in combination, in the removal of contaminants of emerging concern (CECs) contained in hospital wastewaters, focusing on pharmaceuticals. The optimisation of the single technologies was performed using synthetic wastewater composed of four refractory pharmaceuticals, (carbamazepine-CBZ, lorazepam-LZP, ketoprofen-KTP, 10,11-epoxicarbamazepine-E-CBZ), first alone and then in mixture, in an initial concentration of 1 mg L−1 each. Once the best operational conditions for EO and O3 were defined, their combination (both simultaneous and sequential) was evaluated for the mixture of the selected pharmaceuticals. The treatment solution that showed the best performance was the simultaneous combination of O3 and EO. This treatment was validated using real hospital wastewater previously treated through a moving bed biofilm reactor (MBBR), evaluating its viability by testing the toxicity of the final effluent via Vibrio fischeri inhibition tests. The obtained results showed that the simultaneous combination of O3 and EO as the polishing step after a biological treatment is a very promising solution for hospital wastewater treatment, allowing for obtaining a non-toxic effluent and full degradation of refractory compounds. The disinfection potential of the proposed AOP was also assessed by determining Escherichia coli inactivation potential. [ABSTRACT FROM AUTHOR]

Hospital wastewater can contaminate the environment with antibiotic-resistant and virulent bacteria. We analyzed wastewater samples from four hospitals in Ardabil province, Iran for Enterococcus faecium and Enterococcus faecalis using culture and molecular methods. We also performed antimicrobial susceptibility testing and polymerase chain reaction testing for resistance and virulence genes. Out of 141 enterococci isolates, 68.8% were E. faecium and 23.4% were E. faecalis. Ciprofloxacin and rifampicin showed the highest level of resistance against E. faecalis and E. faecium isolates at 65%. High-level gentamicin resistance (HLGR), high-level streptomycin resistance (HLSR), ampicillin, and vancomycin resistance were observed in 25, 5, 10, and 5.15% of E. faecium, and 15, 6, 15, and 3.03% of E. faecalis isolates, respectively. The ant(60 )-Ia and ant(30 )-Ia genes that were responsible for streptomycin resistance were observed in HLSR isolates and aph(30 )-IIIa and aac(60 ) Ieaph(2″)-Ia genes accounting for gentamicin resistance were detected in HLGR isolates. vanA was the predominant gene detected in vancomycin-resistant isolates. The majority of isolates were positive for gelE, asa1, esp, cylA, and hyl virulence genes. We found that drug-resistant and virulent E. faecalis and E. faecium isolates were prevalent in hospital wastewater. Proper treatment strategies are required to prevent their dissemination into the environment. [ABSTRACT FROM AUTHOR]

Antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in treated hospital wastewater effluents constitute a major environmental and public health concern. The aim of this study was to investigate the antibiotic resistance patterns of Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa isolated from wastewater effluent at the Benjamin Mkapa Hospital (BMH) in Dodoma, Tanzania. These bacteria were selected to represent the most prevalent gram-negative bacteria found in hospital wastewater, and they have the potential to generate resistance and spread resistance genes to antibiotics. The wastewater BMH is treated in a Constructed Wetland (CW) planted with Typha latifolia before being released into the environment. The bacteria were isolated from wastewater effluent collected at the outlet of the CW. Isolated bacteria were analyzed for antibiotic resistance by disc diffusion method. Molecular identification of bacterial species was performed by using 16S rRNA. The results show that Klebsiella ssp. was the most common isolate detected, with a prevalence of 39.3%, followed by E. coli (27.9%) and Pseudomonas ssp. (18.0%). Klebsiella ssp. were more resistant than Pseudomonas ssp. for Tetracycline, Gentamycin, Ciprofloxacin, and Sulfamethoxazole. Pseudomonas ssp. were more resistant than Klebsiella ssp. for Ceftriaxone and Azithromycin. Klebsiella ssp. harbored more resistance genes (40%), followed by Pseudomonas ssp. (35%) and E. coli (20%). The findings of this investigation indicate that the effluent from the CW requires additional treatment to reduce discharged ARB and ARGs in the receiving water bodies. As a result, the effluent quality of the CW should be continuously monitored and assessed, and further developments for treating the final effluent are necessary. [ABSTRACT FROM AUTHOR]

A carbapenem-resistant Escherichia coli strain C-SRM-3 was isolated from hospital wastewater effluent in Hangzhou city, China in March 2022. Analysis of the whole genome sequence showed that this blaNDM-13-positive strain belonged to an internationally recognized high-risk clone ST410 responsible for the dissemination of carbapenem resistance in E. coli. This isolate displayed a multidrug-resistant phenotype and carried a cassette of antibiotic-resistant genes. blaNDM-13 gene was successfully transferred to the recipient E. coli C600 via conjugation. WGS results revealed that blaNDM-13 gene was located on an IncI1 type plasmid replicon. The phylogenetic reconstruction showed that wastewater-sourced C-SRM-3 strain was located in a single branch, far removed from human-derived and animal-sourced isolates. The detection of blaNDM-13 in hospital wastewater suggests that continuous monitoring of antibiotic-resistant genes in the environment is critical for the prevention of carbapenem-resistant bacteria spreading. [ABSTRACT FROM AUTHOR]

Worldwide observations revealed increased frequencies of multi-resistant Enterobacterales and resistance genes in hospital wastewater compared to any other type of wastewater. Despite the description of clonal lineages possibly adapted to hospital wastewater, little is known about long term persistence as well as evolution of these lineages. In this study, wastewater isolates of different Enterobacterales species from a tertiary care hospital were investigated with 2.5 years distance. Whole Genome Sequencing (WGS) and resistance gene identification were performed for E. coli , C. freundii , S. marcescens , K. pneumoniae , K. oxytoca , and E. cloacae isolates (n = 59), isolated in 2022 and compared with strains isolated from the same wastewater pipeline in 2019 (n = 240). Individual clonal lineages with highly related isolates could be identified in all species identified more than once in 2022 that appear to persist in the wastewater drainage. A common motif of all persistent clonal lineages was the carriage of mobile genetic elements encoding carbapenemase genes with hints for horizontal gene transfer in persistent clones in this environment observed over the 2.5-year period. Multiple plasmid replicons could be detected in both years. In 2022 isolates bla VIM-1 replaced bla OXA-48 as the most common carbapenemase gene compared to 2019. Interestingly, despite a similar abundance of carbapenemase genes (>80% of all isolates) at both time points genes encoding extended spectrum β-lactamases decreased over time. This data indicates that hospital wastewater continuously releases genes encoding carbapenemases to the urban wastewater system. The evolution of the resident clones as well as the reasons for the selection advantage in this specific ecological niche needs to be further investigated in the future. [ABSTRACT FROM AUTHOR]

The separate, advanced treatment of hospital wastewater might be a promising approach to prevent the dissemination of residual compounds of high environmental concern, like pharmaceuticals, viruses and pathogenic microorganisms. This study investigates the performance of a full-scale, on-site treatment plant, consisting of a membrane bioreactor and a subsequent ozonation, at a German hospital. We analysed the elimination of pharmaceutical residues, microbiological parameters and SARS-CoV-2 RNA fragments. Additionally, we conducted an orienting study on the practicability of implementing targeted wastewater monitoring at a hospital. Our results demonstrate that after 10 years of stable operation, the treatment plant works highly efficiently regarding the elimination of pharmaceuticals and bacterial indicators. Elimination rates for pharmaceutical substances were above 90%, and log reductions of up to 6 log10 units for microbiological parameters were achieved. SARS-CoV-2 RNA could be detected and quantified in the influent but not in the effluent. The RNA load in the raw wastewater showed good correspondence with COVID-19 case numbers in the hospital. We showed that the full-scale on-site treatment of hospital wastewater is technically feasible and contributes to sustainable hospital effluent management and that monitoring biological markers on the building level might be a useful complementary tool for disease surveillance. HIGHLIGHTS Separate on-site treatment of hospital wastewater with a membrane bioreactor and subsequent ozonation is a promising treatment technology to cope with future challenges in wastewater management like micropollutants and microbial hazards.; Elimination rates of over 90% for pharmaceutical residues and removals of up to 6 log10 units for bacterial indicators were achieved by a full-scale hospital wastewater treatment plant (WWTP).;