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Seyedin M, Hassanpour A, Jalali A, Raisee M. Robust optimization of a novel ultraviolet (UV) photoreactor for water disinfection: A neural network approach. CHEMOSPHERE 2024; 362:142788. [PMID: 38977250 DOI: 10.1016/j.chemosphere.2024.142788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 05/30/2024] [Accepted: 07/04/2024] [Indexed: 07/10/2024]
Abstract
To optimize the ultraviolet (UV) water disinfection process, it is crucial to determine the ideal geometric dimensions of a corresponding model that enhance performance while minimizing the impact of uncertain photoreactor inputs. As water treatment directly affects people's lives, it is crucial to eliminate the risks associated with the non-ideal performance of disinfection photoreactors. Input uncertainties greatly affect photoreactor performance, making it essential to develop a robust optimization algorithm in advance to mitigate these effects and minimize the physical and financial resources required for constructing the photoreactors. In the suggested algorithm, a two-objective genetic algorithm is integrated with a non-intrusive polynomial chaos expansion (PCE) technique. Additionally, the Sobol sampling method is employed to select the necessary samples for understanding the system's behavior. An artificial neural network surrogate model is trained using sufficient data points derived from computational fluid dynamics (CFD) simulations. A novel type of UV photoreactors working based on exterior reflectors is chosen to optimize the process with three uncertain input parameters, including UV lamp power, UV transmittance of water, and diffusive fraction of the reflective surface. In addition, four geometrical design variables are considered to find the optimal configuration of the photoreactor. The standard deviation (SD) and the reciprocal of log reduction value (LRV) are set as the objective functions, calculated using PCE. The optimal design provides a LRV of 3.95 with SD of 0.2. The coefficient of variation (CoV) of the model significantly declines up to 7%, indicating the decreased sensitivity of the photoreactor to the input uncertainties. Additionally, it is discovered that the robust model exhibits minimal sensitivity to changes in reflectivity in various flow rates, and its output variability aligns with the SD obtained through robust optimization.
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Affiliation(s)
- Mahla Seyedin
- School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Amirhossein Hassanpour
- School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Alireza Jalali
- School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran.
| | - Mehrdad Raisee
- School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran
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2
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Oliveira IM, Gomes IB, Simões LC, Simões M. A review of research advances on disinfection strategies for biofilm control in drinking water distribution systems. WATER RESEARCH 2024; 253:121273. [PMID: 38359597 DOI: 10.1016/j.watres.2024.121273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 01/31/2024] [Accepted: 02/05/2024] [Indexed: 02/17/2024]
Abstract
The presence of biofilms in drinking water distribution systems (DWDS) is responsible for water quality deterioration and a possible source of public health risks. Different factors impact the biological stability of drinking water (DW) in the distribution networks, such as the presence and concentration of nutrients, water temperature, pipe material composition, hydrodynamic conditions, and levels of disinfectant residual. This review aimed to evaluate the current state of knowledge on strategies for DW biofilm disinfection through a qualitative and quantitative analysis of the literature published over the last decade. A systematic review method was performed on the 562 journal articles identified through database searching on Web of Science and Scopus, with 85 studies selected for detailed analysis. A variety of disinfectants were identified for DW biofilm control such as chlorine, chloramine, UV irradiation, hydrogen peroxide, chlorine dioxide, ozone, and others at a lower frequency, namely, electrolyzed water, bacteriophages, silver ions, and nanoparticles. The disinfectants can impact the microbial communities within biofilms, reduce the number of culturable cells and biofilm biomass, as well as interfere with the biofilm matrix components. The maintenance of an effective residual concentration in the water guarantees long-term prevention of biofilm formation and improves the inactivation of detached biofilm-associated opportunistic pathogens. Additionally, strategies based on multi-barrier processes by optimization of primary and secondary disinfection combined with other water treatment methods improve the control of opportunistic pathogens, reduce the chlorine-tolerance of biofilm-embedded cells, as well as decrease the corrosion rate in metal-based pipelines. Most of the studies used benchtop laboratory devices for biofilm research. Even though these devices mimic the conditions found in real DWDS, future investigations on strategies for DW biofilm control should include the validity of the promising strategies against biofilms formed in real DW networks.
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Affiliation(s)
- Isabel Maria Oliveira
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal; ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal
| | - Inês Bezerra Gomes
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal; ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal
| | - Lúcia Chaves Simões
- CEB - Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; LABBELS - Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, Braga/Guimarães, Portugal
| | - Manuel Simões
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal; ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal.
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3
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Xue Q, Deng L, Tang Q, Wang T, Luo W. Formation of halonitromethanes from benzylamine during UV/chlorination: Impact factors, toxicity alteration, and pathways. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:16437-16452. [PMID: 38319423 DOI: 10.1007/s11356-024-32132-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 01/18/2024] [Indexed: 02/07/2024]
Abstract
Halonitromethanes (HNMs), a representative nitrogen-containing disinfection byproduct, have gained significant concerns due to their higher cytotoxicity and genotoxicity. UV/chlorination is considered a promising alternative disinfection technology for chlorination. This study aimed to investigate the HNMs formation from benzylamine (BZA) during UV/chlorination. The experimental results revealed that the yields of HNMs initially raised to a peak then dropped over time. Higher chlorine dosage and BZA concentration promoted the formation of HNMs, whereas alkaline pH inhibited their formation. The presence of bromine ion (Br-) not only converted chlorinated-HNMs (Cl-HNMs) to brominated (chlorinated)-HNMs Br (Cl)-HNMs) and brominated-HNMs (Br-HNMs) but also enhanced the total concentration of HNMs. Besides, the calculated cytotoxicity index (CTI) and genotoxicity index (GTI) of HNMs were elevated by 68.97% and 60.66% as Br- concentration raised from 2 to 6 µM. The possible formation pathways of HNMs from BZA were proposed based on the intermediates identified by a gas chromatography/mass spectrometry (GC/MS). In addition, the formation rules of HNMs in actual water verified the results in deionized water during UV/chlorination. The results of this study provide basic data and a theoretical basis for the formation and control of HNMs, which is conducive to applying UV/chlorination.
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Affiliation(s)
- Qi Xue
- Department of Municipal Engineering, Southeast University, Jiangning, Nanjing, Jiangsu, 211189, People's Republic of China
| | - Lin Deng
- Department of Municipal Engineering, Southeast University, Jiangning, Nanjing, Jiangsu, 211189, People's Republic of China.
| | - Qian Tang
- Department of Municipal Engineering, Southeast University, Jiangning, Nanjing, Jiangsu, 211189, People's Republic of China
| | - Tao Wang
- Department of Municipal Engineering, Southeast University, Jiangning, Nanjing, Jiangsu, 211189, People's Republic of China
| | - Wei Luo
- Department of Municipal Engineering, Southeast University, Jiangning, Nanjing, Jiangsu, 211189, People's Republic of China
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Zhang J, Li W, Zhang X, Wang X, Lv L. Combined applications of UV and chlorine on antibiotic resistance control: A critical review. ENVIRONMENTAL RESEARCH 2024; 243:117884. [PMID: 38072103 DOI: 10.1016/j.envres.2023.117884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 12/03/2023] [Accepted: 12/04/2023] [Indexed: 12/17/2023]
Abstract
Environmental health problems caused by antibiotic-resistant bacteria (ARB) and antibiotic-resistant genes (ARGs) have become a global concern. ARB and ARGs have been continuously detected in various water environments, which pose a new challenge for water quality safety assurance. Disinfection is a key water treatment process to eliminate pathogenic microorganisms in water, and combined chlorine and UV processes (the UV/Cl2 process, the UV-Cl2 process, and the Cl2-UV process) are considered potential disinfection methods to control antibiotic resistance. This review documented the efficacy and mechanism of combined UV and chlorine processes for the control of antibiotic resistance, as well as the effects of chlorine dose, solution pH, UV wavelength, and water matrix on the effectiveness of the processes. There are knowledge gaps in research on the combined chlorine and UV processes for antibiotic resistance control, in particular the UV-Cl2 process and the Cl2-UV process. In addition, changes in the structure of microbial communities and the distribution of ARGs, which are closely related to the spread of antibiotic resistance in the water, induced by combined processes were also addressed. Whether these changes could lead to the re-transmission of antibiotic resistance and harm human health may need to be further evaluated.
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Affiliation(s)
- Jingyi Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China; School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Weiguang Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China; School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Xinran Zhang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, China
| | - Xuhui Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China; School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Longyi Lv
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China
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El-Newehy MH, Aldalbahi A, Thamer BM, Hameed MMA. Establishment and inactivation of mono-species biofilm in a semipilot-scale water distribution system using nanocomposite of silver nanoparticles/montmorillonite loaded cationic chitosan. Int J Biol Macromol 2024; 258:128874. [PMID: 38128797 DOI: 10.1016/j.ijbiomac.2023.128874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 12/10/2023] [Accepted: 12/16/2023] [Indexed: 12/23/2023]
Abstract
This study presents a novel approach in the synthesis and characterization of nanocomposites comprising cationic chitosan (CCS) blended with varying concentrations of silver nanoparticles/montmorillonite (AgNPs/MMT). AgNPs/MMT was synthesized using soluble starch as a reducing and stabilizing agent. Subsequently, nanocomposites, namely CCS/AgMMT-0, CCS/AgMMT-0.5, CCS/AgMMT-1.5, and CCS/AgMMT-2.5, were developed by blending 2.5 g of CCS with 0, 0.5, 1.5, and 2.5 g of AgNPs/MMT, respectively, and the corresponding nanocomposites were prepared using ball milling technique. Transmission electron microscopy (TEM) analysis revealed the formation of nanocomposites that exhibiting nearly spherical morphologies. Dynamic light scattering (DLS) measurements displayed average particle sizes of 1183 nm, 131 nm, 140 nm, and 188 nm for CCS/AgMMT-0, CCS/AgMMT-0.5, CCS/AgMMT-1.5, and CCS/AgMMT-2.5, respectively. The narrow polydispersity index (~0.5) indicated uniform particle size distributions across the nanocomposites, affirming monodispersity. Moreover, the zeta potential values exceeding 30 mV across all nanocomposites that confirmed their stability against agglomeration. Notably, CCS/AgMMT-2.5 nanocomposite exhibited potent antibacterial and antibiofilm properties against diverse pipeline materials. Findings showed that after 15 days of incubation, the highest populations of biofilm cells, Pseudomonas aeruginosa biofilm, developed over UPVC, MDPE, DCI, and SS, with corresponding HPCs of 4.79, 6.38, 8.81, and 7.24 CFU/cm2. The highest cell densities of Enterococcus faecalis biofilm in the identical situation were 4.19, 5.89, 8.12, and 6.9 CFU/cm2. The nanocomposite CCS/AgMMT-2.5 exhibited the largest measured zone of inhibition (ZOI) against both P. aeruginosa and E. faecalis, with measured ZOI values of 19 ± 0.65 and 17 ± 0.21 mm, respectively. Remarkably, the research indicates that the youngest biofilm exhibited the most notable rate of inactivation when exposed to a dose of 150 mg/L, in comparison to the mature biofilm. These such informative findings could offer valuable insights into the development of effective antibiofilm agents and materials applicable in diverse sectors such as water treatment facilities, medical devices, and industrial pipelines.
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Affiliation(s)
- Mohamed H El-Newehy
- Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
| | - Ali Aldalbahi
- Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Badr M Thamer
- Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Meera Moydeen Abdul Hameed
- Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
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Zhang T, Li K, Liu X. DBP-FP change of biofilm in drinking water distribution system induced by sequential UV and chlorine disinfection: Effect of UV dose and influencing mechanism. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 338:122716. [PMID: 37832779 DOI: 10.1016/j.envpol.2023.122716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 09/27/2023] [Accepted: 10/07/2023] [Indexed: 10/15/2023]
Abstract
The issue of biofilm-related disinfection byproducts (DBPs) in drinking water distribution system (DWDS) has garnered significant attention. This study sought to examine the changes in biofilm-originated halogenated DBP formation potential (biofilm DBP-FP) in simulated continuous-flow DWDSs subjected to sequential UV and chlorine disinfection (UV-Cl2) treatments with varying UV doses and to propose the underlying mechanism. The formation potential of trihalomethanes (THMs), haloacetic acids (HAAs), and the total organic halogen (TOX, X = Cl and Br) produced by biofilm were measured. Results showed that the biofilm TOCl-FP was at a minimum with a UV dose of 80 mJ/cm2, corresponding to the lowest amounts of protein and polysaccharides in the extracellular polymeric substances (EPS). Sphingobium, Methylobacterium, and Sphingomonas played a crucial role in protein and polysaccharide biosynthesis. Bacterial community composition characterization together with metabolic function analysis indicated that dominant bacteria varied and metabolic function shifted due to UV-Cl2 disinfection, with Alphaproteobacteria increasing in relative abundance and Bacteroidia showing the opposite trend with increasing UV doses. Correlation analysis suggested that the UV-Cl2 disinfection process led to changes in the water matrix, including organics, inorganics, bacteria, and components that provide environmental pressure for the biofilm. These changes ultimately influenced the properties of the biofilm EPS, which had a direct impact on biofilm DBP-FP.
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Affiliation(s)
- Tuqiao Zhang
- Zhejiang Key Laboratory of Drinking Water Safety and Distribution Technology, Zhejiang University, Hangzhou, 310058, PR China
| | - Kexin Li
- Zhejiang Key Laboratory of Drinking Water Safety and Distribution Technology, Zhejiang University, Hangzhou, 310058, PR China
| | - Xiaowei Liu
- Zhejiang Key Laboratory of Drinking Water Safety and Distribution Technology, Zhejiang University, Hangzhou, 310058, PR China; Ocean College, Zhejiang University, Hangzhou, 310058, PR China.
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7
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Shi Q, Chen Z, Yan H, Xu M, Cao KF, Mao Y, Chen X, Hu HY. Identification of significant live bacterial community shifts in different reclaimed waters during ozone and chlorine disinfection. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 896:165199. [PMID: 37391159 DOI: 10.1016/j.scitotenv.2023.165199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 06/12/2023] [Accepted: 06/27/2023] [Indexed: 07/02/2023]
Abstract
Ozone and chlorine are the most widely used disinfectants for water and wastewater disinfection. They play important role in microbial inactivation but could also pose a considerable selection effect on the microbial community of reclaimed water. Classical culture-based methods that rely on the assessment of conventional bacterial indicators (e.g., coliform bacteria) could hardly reflect the survival of disinfection residual bacteria (DRB) and hidden microbial risks in disinfected effluents. Hence, this study investigated the shifts of live bacterial community during ozone and chlorine disinfection in three reclaimed waters (i.e., two secondary effluents and one tertiary effluent), adopting Illumina Miseq sequencing technology in combination with a viability assay, propidium monoazide (PMA) pretreatment. Notably, statistical analyses of Wilcoxon rank-sum test confirmed the existance of distinct differences in bacterial community structure between samples with or without PMA pretreatment. On the phylum level, Proteobacteria commonly dominated in three undisinfected reclaimed waters, while ozone and chlorine disinfection posed varied effects on its relative abundance among different influents. On the genus level, ozone and chlorine disinfection significantly changed the bacterial composition and dominant species in reclaimed waters. Specifically, the typical DRB identified in ozone disinfected effluents were Pseudomonas, Nitrospira and Dechloromonas, while for chlorine disinfected effluents, Pseudomonas, Legionella, Clostridium, Mycobacterium and Romboutsia were recognized as typical DRB, which call for much attention. The Alpha and Beta diversity analysis results also suggested that different influent compositions greatly affected the bacterial community structure during disinfection processes. Since the experiments in present study were conducted in a short period and the dataset was relatively limited, prolonged experiment under different operational conditions are needed in future to illustrate the potential long-term effects of disinfection on the microbial community structure. The findings of this study could provide insights into microbial safety concern and control after disinfection for sustainable water reclamation and reuse.
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Affiliation(s)
- Qi Shi
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China.
| | - Han Yan
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Meiying Xu
- State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, PR China
| | - Ke-Fan Cao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yu Mao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Xiaowen Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Jiangsu, Suzhou, 215163, PR China
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Shekhawat SS, Saini P, Upadhyay A, Pareek N, Arora S, Gupta AB, Vivekanand V. Treatment of clinical laboratory sewage using a decentralized treatment unit and risk reduction for its reuse in irrigation using hybrid disinfection. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 344:118684. [PMID: 37536236 DOI: 10.1016/j.jenvman.2023.118684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/08/2023] [Accepted: 07/25/2023] [Indexed: 08/05/2023]
Abstract
The disinfection efficacy of standalone chlorine, UV and their combined approach (hybrid) was investigated for the coliform removal in BioKube 1 and 2 treated effluents collected from different environmental settings of clinical and domestic wastes. Chlorine and UV disinfection were applied to BioKube treated wastewater with doses from 0 to 4 mg L-1 and 0-166 mJ cm-2 respectively. Combined disinfection strategies were designed to reduce the dose of chlorine and UV and to exploit the synergistic effect of them. The culturable coliforms were enumerated in treated wastewater sample (control), immediately after (reduction), and 24 h post disinfections (regrowth) using culture media plating and colilert-18 media. Both the BioKube systems (1 and 2) were effective in achieving the strict norms of physicochemical parameters, but not following the coliform counts of treated effluent for reuse in irrigation. A hybrid strategy of chlorine followed by UV was found to be the most effective among various standalone and combination approaches for the removal of coliforms (>4 log ER or <1000 CFU/100 mL) from both the treated effluents. However, coliform present in treated effluent of BioKube 1 were resisting (regrowth) against all kind of applied disinfectants except chlorine followed by UV dose at or more than 0.5 mg L-1 + 41 mJ cm-2. Limited reports are available on hybrid disinfection approaches with decentralized packaged sewage treatment units and this study would help to adopt as an effective tertiary treatment strategy for reuse of treated sewage for irrigation while ensuring public health safety.
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Affiliation(s)
- Sandeep Singh Shekhawat
- Centre for Energy and Environment, Malaviya National Institute of Technology Jaipur, JLN Marg, Jaipur, 302017, India; Department of Mechanical-Mechatronics Engineering, The LNM Institute of Information Technology, Jaipur, 302031, India
| | - Pankaj Saini
- Department of Civil Engineering, Malaviya National Institute of Technology Jaipur, JLN Marg, Jaipur, 302017, India
| | - Aparna Upadhyay
- Department of Civil Engineering, Malaviya National Institute of Technology Jaipur, JLN Marg, Jaipur, 302017, India
| | - Nidhi Pareek
- Department of Microbiology, School of Life Sciences, Central University of Rajasthan Bandarsindri, Ajmer, Kishangarh, Rajasthan, 305801, India
| | - Sudipti Arora
- B. Lal Institute of Biotechnology, Jaipur, Rajasthan 302017, India
| | - Akhilendra Bhushan Gupta
- Department of Civil Engineering, Malaviya National Institute of Technology Jaipur, JLN Marg, Jaipur, 302017, India
| | - Vivekanand Vivekanand
- Centre for Energy and Environment, Malaviya National Institute of Technology Jaipur, JLN Marg, Jaipur, 302017, India.
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Oliveira IM, Gomes IB, Moniz T, Simões LC, Rangel M, Simões M. Realism-based assessment of the efficacy of potassium peroxymonosulphate on Stenotrophomonas maltophilia biofilm control. JOURNAL OF HAZARDOUS MATERIALS 2023; 460:132348. [PMID: 37625295 DOI: 10.1016/j.jhazmat.2023.132348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 08/04/2023] [Accepted: 08/17/2023] [Indexed: 08/27/2023]
Abstract
The potential of pentapotassium bis(peroxymonosulphate) bis(sulphate) (OXONE) to control biofilms in drinking water distribution systems (DWDS) was evaluated and compared to chlorine disinfection. Mature biofilms of drinking water (DW)-isolated Stenotrophomonas maltophilia were formed using a simulated DWDS with a rotating cylinder reactor (RCR). After 30 min of exposure, OXONE at 10 × minimum bactericidal concentration (MBC) caused a significant 4 log reduction of biofilm culturability in comparison to the unexposed biofilms and a decrease in the number of non-damaged cells below the detection limit (4.8 log cells/cm2). The effects of free chlorine were restricted to approximately 1 log reduction in both biofilm culturability and non-damaged cells. OXONE in synthetic tap water (STW) at 25 ºC was more stable over 40 days than free chlorine in the same conditions. OXONE solution exhibited a disinfectant decrease of about 10% of the initial concentration during the first 9 days, and after this time the values remained stable. Whereas possible reaction of chlorine with inorganic and organic substances in STW contributed to free chlorine depletion of approximately 48% of the initial concentration. Electron paramagnetic resonance (EPR) spectroscopy studies confirmed the presence of singlet oxygen and other free radicals during S. maltophilia disinfection with OXONE. Overall, OXONE constitutes a relevant alternative to conventional DW disinfection for effective biofilm control in DWDS.
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Affiliation(s)
- Isabel M Oliveira
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal; ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal
| | - Inês B Gomes
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal; ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal
| | - Tânia Moniz
- REQUIMTE, LAQV - Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, Rua do Campo Alegre, s/n, 40169-007 Porto, Portugal; REQUIMTE, LAQV - Instituto de Ciências Biomédicas de Abel Salazar, University of Porto, Rua de Jorge Viterbo de Ferreira, 228, 4050-313 Porto, Portugal
| | - Lúcia Chaves Simões
- CEB - Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; LABBELS - Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, Braga/Guimarães, Portugal
| | - Maria Rangel
- REQUIMTE, LAQV - Instituto de Ciências Biomédicas de Abel Salazar, University of Porto, Rua de Jorge Viterbo de Ferreira, 228, 4050-313 Porto, Portugal
| | - Manuel Simões
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal; ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias, 4200-465 Porto, Portugal.
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10
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Cao KF, Chen Z, Sun YG, Huang BH, Shi Q, Mao Y, Wu YH, Lu Y, Hu HY. Modeling and optimization of synergistic ozone-ultraviolet-chlorine process for reclaimed water disinfection: From laboratory tests to software simulation. WATER RESEARCH 2023; 243:120373. [PMID: 37494748 DOI: 10.1016/j.watres.2023.120373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 06/26/2023] [Accepted: 07/15/2023] [Indexed: 07/28/2023]
Abstract
The ozone-ultraviolet (UV)-chlorine process is a highly effective method of disinfection in water reuse system, but currently still lacks precise quantification and accurate control. It is difficult to determine the dosage of each disinfectant because of the complex interactions that occur between disinfection units and the complicated mathematical calculation required. In this study, we proposed a dosage optimization model for ozone-UV-chlorine synergistic disinfection process. The model was able to identify the cost-effective doses of the disinfectants under the constraints of microbial inactivation, decolorization, and residual chlorine retention requirements. Specifically, the simulation of microbial inactivation rates during synergistic disinfection process was accomplished through quantification of the synergistic effects between disinfection units and the introduction of enhancement coefficients. In order to solve this optimization model rapidly and automatically, a MATLAB-based software program with graphical user interface was developed. This software consisted of calibration unit, prediction unit, assessment unit, and optimization unit, and was able to simulate synergistic ozone-UV-chlorine process and identify the optimal dose of ozone, UV, and chlorine. Validation experiments revealed good agreements between the experimental data and the results calculated by the developed software. The developed software is believed to help the water reclamation plants improve disinfection efficiency and reduce the operational costs of synergistic disinfection processes.
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Affiliation(s)
- Ke-Fan Cao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, China.
| | - Yi-Ge Sun
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, China
| | - Bang-Hao Huang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, China
| | - Qi Shi
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, China
| | - Yu Mao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, China
| | - Yin-Hu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, China
| | - Yun Lu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, China
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Jiangsu, Suzhou 215163, China.
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11
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Oliveira IM, Gomes IB, Plácido A, Simões LC, Eaton P, Simões M. The impact of potassium peroxymonosulphate and chlorinated cyanurates on biofilms of Stenotrophomonas maltophilia: effects on biofilm control, regrowth, and mechanical properties. BIOFOULING 2023; 39:691-705. [PMID: 37811587 DOI: 10.1080/08927014.2023.2254704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 08/27/2023] [Indexed: 10/10/2023]
Abstract
The activity of two chlorinated isocyanurates (NaDCC and TCCA) and peroxymonosulphate (OXONE) was evaluated against biofilms of Stenotrophomonas maltophilia, an emerging pathogen isolated from drinking water (DW), and for the prevention of biofilm regrowth. After disinfection of pre-formed 48 h-old biofilms, the culturability was reduced up to 7 log, with OXONE, TCCA, and NaDCC showing more efficiency than free chlorine against biofilms formed on stainless steel. The regrowth of biofilms previously exposed to OXONE was reduced by 5 and 4 log CFU cm-2 in comparison to the unexposed biofilms and biofilms exposed to free chlorine, respectively. Rheometry analysis showed that biofilms presented properties of viscoelastic solid materials, regardless of the treatment. OXONE reduced the cohesiveness of the biofilm, given the significant decrease in the complex shear modulus (G*). AFM analysis revealed that biofilms had a fractured appearance and smaller bacterial aggregates dispersed throughout the surface after OXONE exposure than the control sample. In general, OXONE has been demonstrated to be a promising disinfectant to control DW biofilms, with a higher activity than chlorine. The results also show the impact of the biofilm mechanical properties on the efficacy of the disinfectants in biofilm control.
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Affiliation(s)
- I M Oliveira
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
| | - I B Gomes
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
| | - A Plácido
- REQUIMTE/LAQV - Associated Laboratory for Green Chemistry of the Network of Chemistry and Technology, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, Porto, Portugal
| | - L C Simões
- CEB - Centre of Biological Engineering, University of Minho, Braga, Portugal
- LABBELS - Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, Braga/Guimarães, Portugal
| | - P Eaton
- REQUIMTE/LAQV - Associated Laboratory for Green Chemistry of the Network of Chemistry and Technology, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, Porto, Portugal
- The Bridge, School of Chemistry, University of Lincoln, Lincoln, UK
| | - M Simões
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
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12
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Liang Z, Yao J, Ma H, Peng W, Xia X, Chen Y. A sludge bulking wastewater treatment plant with an oxidation ditch-denitrification filter in a cold region: bacterial community composition and antibiotic resistance genes. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:33767-33779. [PMID: 36495431 DOI: 10.1007/s11356-022-24591-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 12/01/2022] [Indexed: 06/17/2023]
Abstract
Bacterial community structure of activated sludge directly affects the stable operation of WWTPS, and these bacterial communities may carry a variety of antibiotic resistance genes (ARGs), which is a threat to the public health. This study employed 16S rRNA gene sequencing and metagenomic sequencing to investigate the bacterial community composition and the ARGs in a sludge bulking oxidation ditch-denitrification filter WWTP in a cold region. The results showed that Trichococcus (20.34%), Blautia (7.72%), and Faecalibacterium (3.64%) were the main bacterial genera in the influent. The relative abundances of norank_f_Saprospiraceae and Candidatus_Microthrix reached 10.24% and 8.40%, respectively, in bulking sludge, and those of norank_f_Saprospiraceae and Candidatus_Microthrix decreased to 6.56 and 7.10% after the anaerobic tank, indicating that the anaerobic tank had an inhibitory effect on filamentous bacteria. After 20 mJ/cm2 UV disinfection, about 540 bacterial genera, such as Romboutsia (7.99%), Rhodoferax (7.98%), and Thermomonas (4.13%), could still be detected in the effluent. The ARGs were 345.11 ppm in the influent and 11.20 ppm in the effluent; 17 subtypes, such as sul1, msrE, aadA5, ErmF, and tet(A), could be detected throughout the entire process. These ARG subtypes were persistent ARGs with a high health risk. Network analysis indicated that the changes in filamentous bacteria norank_f_Saprospiraceae abundance mainly contributed to the abundance shift of MexB, and Acinetobacter mainly increased the abundance of drfA1. These results above will provide theoretical support for the sludge bulking and ARGs controls of WWTPs in cold regions.
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Affiliation(s)
- Zenghui Liang
- College of Ecology and Environment, Xinjiang University, No. 777 Huarui Street, Shuimogou District, Urumqi, 830017, China
| | - Junqin Yao
- College of Ecology and Environment, Xinjiang University, No. 777 Huarui Street, Shuimogou District, Urumqi, 830017, China.
| | - Huiying Ma
- College of Ecology and Environment, Xinjiang University, No. 777 Huarui Street, Shuimogou District, Urumqi, 830017, China
| | - Wei Peng
- College of Architectural Engineering, Xinjiang University, Urumqi, 830017, China
| | - Xueliang Xia
- Second Wastewater Treatment Plant of Changji, Changji, 831100, China
| | - Yinguang Chen
- College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
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13
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Ye C, Zhang K, Wu X, Wan K, Cai WF, Feng M, Yu X. Uncovering novel disinfection mechanisms of solar light/periodate system: The dominance of singlet oxygen and metabolomic insights. JOURNAL OF HAZARDOUS MATERIALS 2023; 443:130177. [PMID: 36308932 DOI: 10.1016/j.jhazmat.2022.130177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 09/30/2022] [Accepted: 10/09/2022] [Indexed: 06/16/2023]
Abstract
Disinfection plays an essential role in waterborne pathogen control and disease prevention, especially during the COVID-19 pandemic. Catalyst-free solar light/periodate (PI) system has recently presented great potential in water disinfection, whereas the in-depth chemical and microbiological mechanisms for efficient bacterial inactivation remain unclear. Our work delineated firstly the critical role of singlet oxygen, instead of reported hydroxyl radicals and superoxide radicals, in dominating bacterial inactivation by the PI/simulated sunlight (SSL) system. Multi-evidence demonstrated the prominent disinfection performance of this system for Staphylococcus aureus in terms of culturability (> 6 logs CFU), cellular integrity, and metabolic activity. Particularly, the excellent intracellular DNA removal (> 95%) indicated that PI/SSL system may function as a selective disinfection strategy to diminish bacterial culturability without damaging the cell membrane. The PI/SSL system could also effectively inhibit bacterial regrowth for > 5 days and horizontal gene transfer between E. coli genera. Nontargeted metabolomic analysis suggested that PI/SSL system inactivated bacteria by triggering the accumulation of intracellular reactive oxygen species and the depletion of reduced glutathione. Additionally, the PI/SSL system could accomplish simultaneous micropollutant removal and bacterial inactivation, suggesting its versatility in water decontamination. Overall, this study deciphers more comprehensive antibacterial mechanisms of this environmentally friendly disinfection system, facilitating the technical development and application of the selective disinfection strategy in environmental pathogen control.
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Affiliation(s)
- Chengsong Ye
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Kaiting Zhang
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Xu Wu
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Kun Wan
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Wei-Feng Cai
- Xiamen Cancer Center, The First Affiliated Hospital of Xiamen University, Xiamen 361009, China
| | - Mingbao Feng
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Xin Yu
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, China.
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14
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Lu YW, Liang XX, Wang CY, Chen D, Liu H. Synergistic nanowire-assisted electroporation and chlorination for inactivation of chlorine-resistant bacteria in drinking water systems via inducing cell pores for chlorine permeation. WATER RESEARCH 2023; 229:119399. [PMID: 36462257 DOI: 10.1016/j.watres.2022.119399] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 10/25/2022] [Accepted: 11/19/2022] [Indexed: 06/17/2023]
Abstract
The widespread use of chlorination (Cl2) in drinking water systems causes the selection of chlorine-resistant bacteria commonly with dense extracellular polymeric substance (EPS) against chlorine permeation, posing significant threat to public health. Herein, a nanowire-assisted electroporation (EP) via locally enhanced electric field was combined with Cl2 to construct the synergistic EP/Cl2 disinfection, with the purposes of inducing cell pores for chlorine permeation and bacterial inactivation. The synergistic effects of EP/Cl2 were observed for inactivation of chlorine-resistant Bacillus cereus (G+, 304 μg DOC-EPS/109 CFU) and Aeromonas media (G-, 35.8 μg), and chlorine-sensitive Escherichia coli (G-, 5.1 μg) that were frequent occurrence in drinking water systems. The EP/Cl2 enabled above 6 log B. cereus inactivation (undetectable live bacteria) at 1.5 V-EP and 0.9 mg/L-Cl2, which was much higher than the individual EP (1.11 log) and Cl2 (1.13 log) disinfection. The cell membrane integrity, intracellular free chlorine levels, and morphology analyses revealed that the electroporation-induced pores on cell wall/membrane destructed the bound EPS barrier for chlorine permeation, and the pore sizes were further enlarged by chlorine oxidation, hence facilitating bacterial inactivation via destroying the cell structures. The excellent disinfection performance for tap water and lake water also suggested its sound application potentials.
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Affiliation(s)
- Ying-Wen Lu
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, PR China
| | - Xiang-Xing Liang
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, PR China
| | - Chen-Yang Wang
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, PR China
| | - Da Chen
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, PR China
| | - Hai Liu
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, PR China.
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15
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Zhou Q, Huang J, Guo K, Lou Y, Wang H, Zhou R, Tang J, Hou P. Spatiotemporal distribution of opportunistic pathogens and microbial community in centralized rural drinking water: One year survey in China. ENVIRONMENTAL RESEARCH 2023; 218:115045. [PMID: 36513125 DOI: 10.1016/j.envres.2022.115045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 11/18/2022] [Accepted: 12/09/2022] [Indexed: 06/17/2023]
Abstract
Centralized water supply in rural areas, supported by small waterworks (small-central mode) and by municipal water treatment plants (urban-extension mode), is an important guarantee to implement the Rural Revitalization Strategy Plan (2018-2022) in China. Opportunistic pathogens (OPs) could not be evaluated by the national drinking water sanitation standards in China (GB 5749-2022), posing potential microbial risks in rural drinking water. In this study, the spatiotemporal distribution of OPs, microbial community and the associated functional composition under two central water supply modes were investigated by molecular approaches. The results indicated that OPs were widely presented in the rural drinking water regardless of water supply modes, and were more abundant than those in the urban tap water. The insufficient residual chlorine and higher turbidity triggered more microbial proliferation, posing a seasonal variation of OPs gene copy numbers and bacterial community compositions. In warm seasons of summer and autumn, the gene copies of E. coli, M. avium, Pseudomonas spp. and the amoeba host Acanthamoeba spp. achieved up to 4.92, 3.94, 6.75 and 3.74 log10 (gene copies/mL), respectively. Potential functional prediction indicated higher relative abundance of pathogenic genes and infectious risks associated with the rural drinking water under small-central water supply mode. This one-year survey of the spatiotemporal distribution of OPs and microbial community provided scientific insights into microbial safety of rural drinking water, prompting attention on small-central water supply mode against OPs risks.
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Affiliation(s)
- Qiaomei Zhou
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, PR China.
| | - Jingang Huang
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, PR China; The Belt and Road Information Research Institute, Hangzhou Dianzi University, Hangzhou, 310018, PR China.
| | - Kangyin Guo
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, PR China; Zhejiang Sunrise Garment Group Co., Ltd., Shengzhou, 312400, PR China
| | - Yucheng Lou
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| | - Haibo Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China.
| | - Rongbing Zhou
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| | - Junhong Tang
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| | - Pingzhi Hou
- The Belt and Road Information Research Institute, Hangzhou Dianzi University, Hangzhou, 310018, PR China
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16
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Jing Z, Lu Z, Zhao Z, Cao W, Wang W, Ke Y, Wang X, Sun W. Molecular ecological networks reveal the spatial-temporal variation of microbial communities in drinking water distribution systems. J Environ Sci (China) 2023; 124:176-186. [PMID: 36182128 DOI: 10.1016/j.jes.2021.10.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 10/12/2021] [Accepted: 10/12/2021] [Indexed: 06/16/2023]
Abstract
Microbial activity and regrowth in drinking water distribution systems is a major concern for water service companies. However, previous studies have focused on the microbial composition and diversity of the drinking water distribution systems (DWDSs), with little discussion on microbial molecular ecological networks (MENs) in different water supply networks. MEN analysis explores the potential microbial interaction and the impact of environmental stress, to explain the characteristics of microbial community structures. In this study, the random matrix theory-based network analysis was employed to investigate the impact of seasonal variation including water source switching on the networks of three DWDSs that used different disinfection methods. The results showed that microbial interaction varied slightly with the seasons but was significantly influenced by different DWDSs. Proteobacteria, identified as key species, play an important role in the network. Combined UV-chlorine disinfection can effectively reduce the size and complexity of the network compared to chlorine disinfection alone, ignoring seasonal variations, which may affect microbial activity or control microbial regrowth in DWDSs. This study provides new insights for analyzing the dynamics of microbial interactions in DWDSs.
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Affiliation(s)
- Zibo Jing
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China; School of Environment, Tsinghua University, Beijing 100084, China
| | - Zedong Lu
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Zhinan Zhao
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Wenfeng Cao
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Weibo Wang
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Yanchu Ke
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Xiaohui Wang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
| | - Wenjun Sun
- School of Environment, Tsinghua University, Beijing 100084, China; Research Institute for Environmental Innovation (Suzhou) Tsinghua, Suzhou 215163, China.
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Machado EC, Freitas DL, Leal CD, de Oliveira AT, Zerbini A, Chernicharo CA, de Araújo JC. Antibiotic resistance profile of wastewater treatment plants in Brazil reveals different patterns of resistance and multi resistant bacteria in final effluents. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159376. [PMID: 36240935 DOI: 10.1016/j.scitotenv.2022.159376] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 10/07/2022] [Accepted: 10/07/2022] [Indexed: 06/16/2023]
Abstract
Wastewater treatment plants (WWTPs) are recognized as important sources of Antibiotic Resistant Bacteria (ARBs) and Antibiotic Resistant Genes (ARGs), and might play a role in the removal and dissemination of antimicrobial resistance (AMR) in the environment. Detailed information about AMR removal by the different treatment technologies commonly applied in urban WWTPs is needed. This study investigated the occurrence, removal and characterization of ARBs in WWTPs employing different technologies: WWTP-A (conventional activated sludge-CAS), WWTP-B (UASB reactor followed by biological trickling filter) and WWTP-C (modified activated sludge followed by UV disinfection-MAS/UV). Samples of raw sewage (RI) and treated effluent (TE) were collected and, through the cultivation-based method using 11 antibiotics, the antibiotic resistance profiles were characterized in a one-year period. MAS was effective in reducing ARB counts (2 to 3 log units), compared to CAS (1 log unit) and UASB/BTF (0.5 log unit). The composition of cultivable ARB differed between RI and TE samples. Escherichia was predominant in RI (56/118); whilst in TE Escherichia (31/118) was followed by Bacillus (22/118), Shigella (14/118) and Enterococcus (14/118). Most of the isolates identified (370/394) harboured at least two ARGs and in over 80 % of the isolates, 4 or more ARG (int1, blaTEM, TetA, sul1 and qnrB) were detected. A reduction in the resistance prevalence was observed in effluents after CAS and MAS processes; whilst a slight increase was observed in treated effluents from UASB/BTF and after UV disinfection stage. The multi-drug resistance (MDR) phenotype was attributed to 84.3 % of the isolates from RI (27/32) and 63.6 % from TE (21/33) samples and 52.3 % of the isolates (34/65) were resistant to carbapenems (imipenem, meropenem, ertapenem). The results indicate that treated effluents are still a source for MDR bacteria and ARGs dissemination to aquatic environments. The importance of biological sewage treatment was reinforced by the significant reductions in ARB counts observed. However, implementation of additional treatments is needed to mitigate MDR bacteria release into the environment.
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Affiliation(s)
- Elayne Cristina Machado
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil
| | - Deborah Leroy Freitas
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil
| | - Cintia Dutra Leal
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil
| | - Amanda Teodoro de Oliveira
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil
| | - Adriana Zerbini
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil
| | - Carlos Augusto Chernicharo
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil
| | - Juliana Calábria de Araújo
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil.
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18
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Yin H, Chen R, Wang H, Schwarz C, Hu H, Shi B, Wang Y. Co-occurrence of phthalate esters and perfluoroalkyl substances affected bacterial community and pathogenic bacteria growth in rural drinking water distribution systems. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 856:158943. [PMID: 36155042 DOI: 10.1016/j.scitotenv.2022.158943] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 09/01/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
The adverse health effects of phthalate esters (PAEs) and perfluoroalkyl substances (PFAS) in drinking water have attracted considerable attention. Our study investigated the effects of PAEs and PFAS on the bacterial community and the growth of potential human pathogenic bacteria in rural drinking water distribution systems. Our results showed that the total concentration of PAEs and PFAS ranged from 1.02 × 102 to 1.65 × 104 ng/L, from 4.40 to 1.84 × 102 ng/L in rural drinking water of China, respectively. PAEs concentration gradually increased and PFAS slowly decreased along the pipeline distribution, compared to concentrations in the effluents of rural drinking water treatment plants. The co-occurrence of higher concentrations of PAEs and PFAS changed the structure and function of the bacterial communities found within these environments. The bacterial community enhanced their ability to respond to fluctuating environmental conditions through up-regulation of functional genes related to extracellular signaling and interaction, as well as genes related to replication and repair. Under these conditions, co-occurrence of PAEs and PFAS promoted the growth of potential human pathogenic bacteria (HPB), therefore increasing the risk of the development of associated diseases among exposed persons. The main HPB observed in this study included Burkholderia mallei, Mycobacterium tuberculosis, Klebsiella pneumoniae, Acinetobacter calcoaceticus, Escherichia coli, and Pseudomonas aeruginosa. Contaminants including particles, microorganisms, PAEs and PFAS were found to be released from corrosion scales and deposits of pipes and taps, resulting in the increase of the cytotoxicity and microbial risk of rural tap water. These results are important to efforts to improve the safety of rural drinking water.
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Affiliation(s)
- Hong Yin
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Ruya Chen
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, Zhejiang, China
| | - Haibo Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Cory Schwarz
- Department of Civil and Environmental Engineering, Rice University, Houston 77005, United States
| | - Haotian Hu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yili Wang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
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19
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Batista AMM, Siqueira JCD, Meynet P, Werner D, Garcia GPP, Davenport RJ, Pereira AD, Siniscalchi LAB, Araújo JCD, Mota Filho CR. Diversity and dynamics of bacterial communities in the drinking water distribution network of a mid-sized city in Brazil. JOURNAL OF WATER AND HEALTH 2022; 20:1733-1747. [PMID: 36573676 DOI: 10.2166/wh.2022.177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
This study assessed the bacterial community composition of a drinking water system (DWS) serving a mid-sized city (120,000 inhabitants) in Brazil. Water samples, including raw and treated water, were collected at seven points throughout the DWS. DNA was extracted and analysed using high-throughput sequencing (Ion Torrent). Free chlorine and turbidity were measured in situ. Results showed that the highest relative abundance of 16S rRNA genes was from phyla Proteobacteria, followed by Bacteroidetes and Actinobacteria. The next most abundant phylum was Cyanobacteria, represented by Arthronema, Calothrix, and Synechococcus. An interesting observation was that the DNA-based analysis suggested a bacterial community change in the distribution network, with treated reservoir water being very different from the network samples. This suggests active microbiology within the distribution network and a tendency for bacterial diversity to decrease after chlorine disinfection but increase after pipeline distribution. In raw water, a predominance of Proteobacteria was observed with reduced Cyanobacteria, showing a negative correlation. In treated water, Proteobacteria were negatively correlated with Bacteroidetes. Finally, 16S rRNA genes from Firmicutes (especially Staphylococcus) had a high abundance in the chlorinated water, which may indicate the phylum's resistance to chlorine residuals. Opportunistic pathogens, e.g., Mycobacteria, Legionella, and Staphylococcus, were also observed.
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Affiliation(s)
- Ana Maria Moreira Batista
- Department of Natural Resources, Environmental Sciences and Technologies, State University of Minas Gerais (João Monlevade Unit), Brasília Avenue, 1304 - Bau, 35930-314 João Monlevade, Minas Gerais, Brazil; Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, 31270-010 Belo Horizonte, Minas Gerais, Brazil E-mail:
| | - Juliano Curi de Siqueira
- Department of Environmental Engineering, Federal University of Lavras, Aquenta Sol, 37200-900, Lavras, Minas Gerais, Brazil
| | - Paola Meynet
- School of Civil Engineering and Geosciences, Newcastle University, NE1 7RU Newcastle upon Tyne, UK
| | - David Werner
- School of Civil Engineering and Geosciences, Newcastle University, NE1 7RU Newcastle upon Tyne, UK
| | - Graziella Patricio Pereira Garcia
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, 31270-010 Belo Horizonte, Minas Gerais, Brazil E-mail:
| | - Russell J Davenport
- School of Civil Engineering and Geosciences, Newcastle University, NE1 7RU Newcastle upon Tyne, UK
| | - Alyne Duarte Pereira
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, 31270-010 Belo Horizonte, Minas Gerais, Brazil E-mail:
| | | | - Juliana Calábria de Araújo
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, 31270-010 Belo Horizonte, Minas Gerais, Brazil E-mail:
| | - Cesar Rossas Mota Filho
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, 31270-010 Belo Horizonte, Minas Gerais, Brazil E-mail:
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20
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Li J, Feng C, Jin J, Yang W, Wang Z. Current understanding on antibacterial mechanisms and research progress of tea polyphenols as a supplementary disinfectant for drinking water. JOURNAL OF WATER AND HEALTH 2022; 20:1611-1628. [PMID: 36448612 DOI: 10.2166/wh.2022.062] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Disinfection by-products (DBPs) generated during the disinfection of drinking water have become an urgent problem. So, tea polyphenol, a natural green disinfectant, has attracted widespread attention in recent years. This review summarizes the antibacterial mechanism of tea polyphenols and the recent findings on tea polyphenols as disinfectants for drinking water. These studies show that tea polyphenol is an antibacterial agent that works through different mechanisms and can be used as a supplementary disinfectant because of its higher lasting effect and economical cost. The dosage of tea polyphenols as a disinfectant of ultrafiltration effluent is the lowest among all the tea polyphenols disinfection methods, which can ensure the microbial safety of drinking water. This application of tea polyphenols is deemed a practical solution to solving the issue of disinfecting drinking water and reducing DBPs. However, it is necessary to further explore the influence of factors such as pipeline materials on the disinfection process and efficacy to expand the application scope of tea polyphenols. The large-scale application of tea polyphenols still needs to be fine-tuned but with new developments in tea polyphenol purification technology and the long-term need for drinking water that is safe for human consumption, tea polyphenols have good prospects for further development.
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Affiliation(s)
- Jing Li
- Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China E-mail: ; National Demonstration Center for Experimental Water Environment Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Cuimin Feng
- Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China E-mail: ; National Demonstration Center for Experimental Water Environment Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Jiyue Jin
- Beijing Waterworks Group, Beijing 100031, China
| | - Weiqi Yang
- Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China E-mail: ; National Demonstration Center for Experimental Water Environment Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Zile Wang
- Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China E-mail: ; National Demonstration Center for Experimental Water Environment Education, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
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21
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Wang HB, Wu YH, Wang WL, Chen Z, Chen GQ, Luo LW, Xue S, Tong X, Zhang ZW, Ikuno N, Ishii K, Hu HY. Comparison of disinfection-residual-bacteria (DRB) after seven different kinds of disinfection: Biofilm formation, membrane fouling and mechanisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 844:157079. [PMID: 35779720 DOI: 10.1016/j.scitotenv.2022.157079] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 06/16/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
Membrane fouling is the Achilles' heel of the reverse osmosis (RO) system for high-quality reclaimed water production. Previous studies have found that after the significant selection effect of traditional disinfection, the remaining disinfection-residual bacteria (DRB) may possess more severe biofouling potentials. To provide more constructive advice for the prevention of biofouling, we compared the RO membrane fouling characteristics of DRB after using five commonly used disinfection methods (NaClO, NH2Cl, ClO2, UV, and O3) and two novel disinfection methods (K2FeO4 and the flow-through electrode system (FES)). Compared with the control group (undisinfected, 21.1 % flux drop), the UV-DRB biofilm aggravated biofouling of the RO membrane (23.4 % flux drop), while the FES, K2FeO4, and NH2Cl treatments showed less severe biofouling, with final flux drops of 6.9 %, 8.1 %, and 8.1 %, respectively. Adenosine triphosphate (ATP) was found to be a capable indicator for predicting the biofouling potential of DRB. Systematic analysis showed that the thickness and density of the DRB biofilms were most closely related to the different fouling degree of RO membranes. Moreover, the relative abundance of bacteria with higher extracellular polymeric substance (EPS) secretion levels, such as Pseudomonas and Sphingomonas, was found closely related with the biofouling degree of RO membranes.
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Affiliation(s)
- Hao-Bin Wang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yin-Hu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China.
| | - Wen-Long Wang
- Key Laboratory of Microorganism Application and Risk Control of Shenzhen, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Gen-Qiang Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Li-Wei Luo
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Song Xue
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Xin Tong
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Zi-Wei Zhang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Nozomu Ikuno
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Kazuki Ishii
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Jiangsu, Suzhou 215163, PR China
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22
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Hegarty B, Dai Z, Raskin L, Pinto A, Wigginton K, Duhaime M. A snapshot of the global drinking water virome: Diversity and metabolic potential vary with residual disinfectant use. WATER RESEARCH 2022; 218:118484. [PMID: 35504157 DOI: 10.1016/j.watres.2022.118484] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/01/2022] [Accepted: 04/19/2022] [Indexed: 05/22/2023]
Abstract
Viruses are important drivers of microbial community ecology and evolution, influencing microbial mortality, metabolism, and horizontal gene transfer. However, the effects of viruses remain largely unknown in many environments, including in drinking water systems. Drinking water metagenomic studies have offered a whole community perspective of bacterial impacts on water quality, but have not yet considered the influences of viruses. In this study, we address this gap by mining viral DNA sequences from publicly available drinking water metagenomes from distribution systems in six countries around the world. These datasets provide a snapshot of the taxonomic diversity and metabolic potential of the global drinking water virome; and provide an opportunity to investigate the effects of geography, climate, and drinking water treatment practices on viral diversity. Both environmental conditions and differences in sample processing were found to influence the viral composition. Using free chlorine as the residual disinfectant was associated with clear differences in viral taxonomic diversity and metabolic potential, with significantly fewer viral populations and less even viral community structures than observed in distribution systems without residual disinfectant. Additionally, drinking water viruses carry antibiotic resistance genes (ARGs), as well as genes to survive oxidative stress and nitrogen limitation. Through this study, we have demonstrated that viral communities are diverse across drinking water systems and vary with the use of residual disinfectant. Our findings offer directions for future research to develop a more robust understanding of how virus-bacteria interactions in drinking water distribution systems affect water quality.
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Affiliation(s)
- Bridget Hegarty
- Department of Civil and Environmental Engineering, Environmental and Water Resources Engineering Building, University of Michigan, 1351 Beal Ave. 181, Ann Arbor, MI 48109-2125, USA
| | - Zihan Dai
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lutgarde Raskin
- Department of Civil and Environmental Engineering, Environmental and Water Resources Engineering Building, University of Michigan, 1351 Beal Ave. 181, Ann Arbor, MI 48109-2125, USA
| | - Ameet Pinto
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Georgia
| | - Krista Wigginton
- Department of Civil and Environmental Engineering, Environmental and Water Resources Engineering Building, University of Michigan, 1351 Beal Ave. 181, Ann Arbor, MI 48109-2125, USA.
| | - Melissa Duhaime
- Department of Ecology and Evolutionary Biology, University of Michigan, 1105N University Ave., 4068 Biological Sciences Building, Ann Arbor, MI 48109-1085, USA.
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23
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Sun W, Lu Z, Zhang Z, Zhang Y, Shi B, Wang H. Ozone and Fenton oxidation affected the bacterial community and opportunistic pathogens in biofilms and effluents from GAC. WATER RESEARCH 2022; 218:118495. [PMID: 35489154 DOI: 10.1016/j.watres.2022.118495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 04/19/2022] [Accepted: 04/20/2022] [Indexed: 06/14/2023]
Abstract
Granular activated carbon (GAC) filtration impacts pathogen colonization and bacterial communities in drinking water. However, the effects of ozone and heterogeneous Fenton oxidation on microbial community composition, in particular opportunistic pathogens (OPs), and their metabolic potential in biofilms and effluents from GAC filtration are not fully understood. The results of our pilot-scale test indicated that Fenton-GAC filtration removed more dissolved organic carbon (DOC, 1.25 mg/L) than ozone-GAC filtration (0.98 mg/L). Excitation-emission matrix (EEM) results showed that Fenton-GAC removed more tyrosine-like proteins and fulvic acid-like materials, while ozone-GAC removed more humic acid-like compounds and tryptophan-like proteins. Illumina HiSeq analysis indicated that Curvibacter and Hydrogenophaga dominated in the Fenton-GAC biofilm, while Bradyrhizobium, Aquabacterium and Limnobacter were predominant in the ozone-GAC biofilm. Functional prediction suggested that the microbial functional gene related to glyoxylate and dicarboxylate metabolism (the pathway for carbohydrate metabolism) was higher in the Fenton-GAC biofilm, resulting in higher contents of protein in extracellular polymeric substances (EPS) in the Fenton-GAC biofilm. Therefore, there were fewer bacteria that detached from the biofilm into the water during the Fenton-GAC filtration process. The lower EPS content in the effluents from Fenton-GAC resulted in bacteria, including OPs, being easier to remove by chlorine. However, ozone oxidation removed more bacteria, including different OPs, than Fenton oxidation, which contributed to fewer bacteria and OPs in the effluents from ozone-GAC. Overall, our results provide a Fenton-GAC treatment process to remove DOC and control OPs in drinking water systems, the cost of which was comparable to that of ozone-GAC.
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Affiliation(s)
- Wei Sun
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Zhili Lu
- Institute of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450045, China
| | - Zeyu Zhang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Institute of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450045, China
| | - Yao Zhang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haibo Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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24
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Dias MF, Leroy-Freitas D, Machado EC, da Silva Santos L, Leal CD, da Rocha Fernandes G, de Araújo JC. Effects of activated sludge and UV disinfection processes on the bacterial community and antibiotic resistance profile in a municipal wastewater treatment plant. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:36088-36099. [PMID: 35060061 DOI: 10.1007/s11356-022-18749-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 01/14/2022] [Indexed: 06/14/2023]
Abstract
Wastewater tertiary treatment has been pointed out as an effective alternative for reducing the concentration of antibiotic resistant bacteria and genes (ARB and ARGs) in wastewaters. The present work aimed to build on the current knowledge about the effects of activated sludge and UV irradiation on antibiotic resistance determinants in biologically treated wastewaters. For that, the microbial community and ARGs' composition of samples collected after preliminary (APT), secondary (AST), and tertiary (ATT) treatments in a full-scale wastewater treatment plant using a modified activated sludge (MAS) system followed by an UV stage (16 mJ/cm2) were investigated through culture-dependent and independent approaches (including metagenomics). A total of 24 phyla and 460 genera were identified, with predominance of Gammaproteobacteria in all samples. Pathogenic genera corresponded to 8.6% of all sequences on average, mainly Acinetobacter and Streptococcus. Significant differences (p < 0.05) in the proportion of pathogens were observed between APT and the other samples, suggesting that the secondary treatment reduced its abundance. The MAS achieved 64.0-99.7% average removal efficiency for total (THB) and resistant heterotrophic bacteria, although the proportions of ARB/THB have increased for sulfamethoxazole, cephalexin, ciprofloxacin, and tetracycline. A total of 107 copies/mL of intI1 gene remained in the final effluent, suggesting that the treatment did not significantly remove this gene and possibly other ARGs. In accordance, metagenomic results suggested that number of reads recruited to plasmid-associated ARGs became more abundant in the pool throughout the treatment, suggesting that it affected more the bacteria without these ARGs than those with it. In conclusion, disinfected effluents are still a potential source for ARB and ARGs, which highlights the importance to investigate ways to mitigate their release into the environment.
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Affiliation(s)
- Marcela França Dias
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, 31270-901, Brazil
| | - Deborah Leroy-Freitas
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, 31270-901, Brazil
| | - Elayne Cristina Machado
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, 31270-901, Brazil
| | - Leticia da Silva Santos
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, 31270-901, Brazil
| | - Cintia Dutra Leal
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, 31270-901, Brazil
| | | | - Juliana Calábria de Araújo
- Department of Sanitary and Environmental Engineering, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, 31270-901, Brazil.
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25
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Gmurek M, Borowska E, Schwartz T, Horn H. Does light-based tertiary treatment prevent the spread of antibiotic resistance genes? Performance, regrowth and future direction. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 817:153001. [PMID: 35031375 DOI: 10.1016/j.scitotenv.2022.153001] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 01/05/2022] [Accepted: 01/05/2022] [Indexed: 06/14/2023]
Abstract
The common occurrence of antibiotic-resistance genes (ARGs) originating from pathogenic and facultative pathogenic bacteria pose a high risk to aquatic environments. Low removal of ARGs in conventional wastewater treatment processes and horizontal dissemination of resistance genes between environmental bacteria and human pathogens have made antibiotic resistance evolution a complex global health issue. The phenomenon of regrowth of bacteria after disinfection raised some concerns regarding the long-lasting safety of treated waters. Despite the inactivation of living antibiotic-resistant bacteria (ARB), the possibility of transferring intact and liberated DNA containing ARGs remains. A step in this direction would be to apply new types of disinfection methods addressing this issue in detail, such as light-based advanced oxidation, that potentially enhance the effect of direct light interaction with DNA. This study is devoted to comprehensively and critically review the current state-of-art for light-driven disinfection. The main focus of the article is to provide an insight into the different photochemical disinfection methods currently being studied worldwide with respect to ARGs removal as an alternative to conventional methods. The systematic comparison of UV/chlorination, UV/H2O2, sulfate radical based-AOPs, photocatalytic processes and photoFenton considering their mode of action on molecular level, operational parameters of the processes, and overall efficiency of removal of ARGs is presented. An in-depth discussion of different light-dependent inactivation pathways, influence of DBP and DOM on ARG removal and the potential bacterial regrowth after treatment is presented. Based on presented revision the risk of ARG transfer from reactivated bacteria has been evaluated, leading to a future direction for research addressing the challenges of light-based disinfection technologies.
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Affiliation(s)
- M Gmurek
- Department of Molecular Engineering, Faculty of Process and Environmental Engineering, Lodz University of Technology, 90-924 Lodz, Poland; Karlsruhe Institute of Technology, Engler-Bunte-Institut, Water Chemistry and Water Technology, 76131 Karlsruhe, Germany; Karlsruhe Institute of Technology, Institute of Functional Interfaces, Microbiology/Molecular Biology Department, Eggenstein-Leopoldshafen, Germany.
| | - E Borowska
- Karlsruhe Institute of Technology, Engler-Bunte-Institut, Water Chemistry and Water Technology, 76131 Karlsruhe, Germany
| | - T Schwartz
- Karlsruhe Institute of Technology, Institute of Functional Interfaces, Microbiology/Molecular Biology Department, Eggenstein-Leopoldshafen, Germany
| | - H Horn
- Karlsruhe Institute of Technology, Engler-Bunte-Institut, Water Chemistry and Water Technology, 76131 Karlsruhe, Germany; DVGW German Technical and Scientific Association for Gas and Water Research Laboratories, Water Chemistry and Water Technology, 76131 Karlsruhe, Germany
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26
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Variation in the Structure and Composition of Bacterial Communities within Drinking Water Fountains in Melbourne, Australia. WATER 2022. [DOI: 10.3390/w14060908] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Modern drinking water distributions systems (DWDSs) have been designed to transport treated or untreated water safely to the consumer. DWDSs are complex environments where microorganisms are able to create their own niches within water, biofilm or sediment. This study was conducted on twelve drinking fountains (of three different types, namely types A, B and C) within the Melbourne (Australia) city area with the aim to (i) characterize the water quality and viable and total counts at each fountain, (ii) compare the differences in the structure and diversity of the bacterial community between bulk water and biofilm and (iii) determine differences between the bacterial communities based on fountain type. Samples of water and biofilm were assessed using both culture-dependent and culture-independent techniques. Heterotrophic plate counts of water samples ranged from 0.5 to 107.5 CFU mL−1, and as expected, total cell counts (cells mL−1) were, on average, 2.9 orders of magnitude higher. Based on the mean relative abundance of operational taxonomic units (OTUs), ANOSIM showed that the structure of the bacterial communities in drinking water and biofilm varied significantly (R = 0.58, p = 0.001). Additionally, ANOSIM showed that across fountain types (in water), the bacterial community was more diverse in fountain type C compared to type A (p < 0.001) and type B (p < 0.001). 16S rRNA next-generation sequencing revealed that the bacterial communities in both water and biofilm were dominated by only seven phyla, with Proteobacteria accounting for 71.3% of reads in water and 68.9% in biofilm. The next most abundant phylum was Actinobacteria (10.4% water; 11.7% biofilm). In water, the genus with the highest overall mean relative abundance was Sphingomonas (24.2%), while Methylobacterium had the highest mean relative abundance in biofilm samples (54.7%). At the level of genus and higher, significant differences in dominance were found across fountain types. In water, Solirubrobacterales (order) were present in type C fountains at a relative abundance of 17%, while the mean relative abundance of Sphingomonas sp. in type C fountains was less than half that in types A (25%) and B (43%). In biofilm, the relative abundance of Sphingomonas sp. was more than double in type A (10%) fountains compared to types B (4%) and C (5%), and Sandarakinorhabdus sp. were high in type A fountains (6%) and low in types B and C (1%). Overall this research showed that there were significant differences in the composition of bacterial communities in water and biofilm from the same site. Furthermore, significant variation exists between microbial communities present in the fountain types, which may be related to age. Long-established environments may lead to a greater chance of certain bacteria gaining abilities such as increased disinfection resistance. Variations between the structure of the bacterial community residing in water and biofilm and differences between fountain types show that it is essential to regularly test samples from individual locations to determine microbial quality.
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Li Q, Lai C, Yu J, Luo J, Deng J, Li G, Chen W, Li B, Chen G. Degradation of diclofenac sodium by the UV/chlorine process: Reaction mechanism, influencing factors and toxicity evaluation. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2021.113667] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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28
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Deng L, Luo W, Huang T, Wen L, Singh RP, Zuo Y, Tan C. Formation and transformation of halonitromethanes from dimethylamine in the presence of bromide during the UV/chlorine disinfection. CHEMOSPHERE 2022; 291:132731. [PMID: 34743802 DOI: 10.1016/j.chemosphere.2021.132731] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/25/2021] [Accepted: 10/27/2021] [Indexed: 06/13/2023]
Abstract
Halonitromethanes (HNMs) is a typical class of nitrogenous disinfection byproducts with high toxicity. The effect of Br- on the formation and transformation of HNMs from dimethylamine (DMA) during the ultraviolet (UV)/chlorine disinfection has been investigated in current study. Results reveal that only chloronitromethane, dichloronitromethane and trichloronitromethane (TCNM) could be found during the UV/chlorine disinfection. Whereas in the presence of Br-, nine species of HNMs could be observed simultaneously. When Br- concentration increased from 0 to 15.0 mg L-1, the predominant species of HNMs were gradually changed from TCNM to dibromonitromethane and tribromonitromethane, which contributed to 23.37% and 31.07% of total HNMs concentration at 15 mg L-1 Br-, respectively. The presence of Br- not only shifted the chlorinated-HNMs (Cl-HNMs) towards brominated-HNMs (Br-HNMs) but also affected the dominant species and total concentration of HNMs. When Br- concentration was 4.0 mg L-1, the formation of HNMs decreased with the increase of pH from 6.0 to 8.0 and increased with the increase of free chlorine and DMA. When free chlorine concentration rose from 0.25 to 1.1 mmol L-1, Br-HNMs were shifted to Br(Cl)-HNMs and then to Cl-HNMs. According to the findings, possible formation and transformation pathways of HNMs from DMA were proposed in the presence of Br- during the UV/chlorine disinfection. Finally, it was proved that the effect of Br- on the trend of HNMs in real water was similar to that in deionized water, but higher HNMs concentrations and delayed peak time were observed in real water. This study can provide the scientific evidence and fundamental data for the applications of UV/chlorine disinfection in the treatment of water containing Br-.
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Affiliation(s)
- Lin Deng
- Department of Municipal Engineering, Southeast University, Nanjing, 211189, China.
| | - Wei Luo
- Department of Municipal Engineering, Southeast University, Nanjing, 211189, China
| | - Tingting Huang
- Department of Municipal Engineering, Southeast University, Nanjing, 211189, China
| | - Longjia Wen
- Department of Municipal Engineering, Southeast University, Nanjing, 211189, China
| | | | - Yuegang Zuo
- Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth North Dartmouth, MA, 02747, USA
| | - Chaoqun Tan
- Department of Municipal Engineering, Southeast University, Nanjing, 211189, China
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Luo X, Zhang B, Lu Y, Mei Y, Shen L. Advances in application of ultraviolet irradiation for biofilm control in water and wastewater infrastructure. JOURNAL OF HAZARDOUS MATERIALS 2022; 421:126682. [PMID: 34388918 DOI: 10.1016/j.jhazmat.2021.126682] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 07/15/2021] [Accepted: 07/16/2021] [Indexed: 05/26/2023]
Abstract
Biofilms are ubiquitous in aquatic environment. While so far, most of the ultraviolet (UV) disinfection studies focus on planktonic bacteria, and only limited attention has been given to UV irradiation on biofilms. To enrich this knowledge, the present paper reviews the up-to-date studies about applying UV to control biofilms in water and wastewater infrastructure. The development of UV light sources from the conventional mercury lamp to the light emitting diode (LED), and the resistance mechanisms of biofilms to UV are summarized, respectively. Then the feasibility to control biofilms with UV is discussed in terms of three technical routes: causing biofilm slough, inhibiting biofilm formation, and inactivating bacteria in the established biofilm. A comprehensive evaluation of the biofilm-targeted UV technologies currently used or potentially useful in water industry is provided as well, after comparative analyses on single/combined wavelengths, continuous/pulsed irradiation, and instant/chronic disinfection effects. UV LEDs are emerging as competitive light sources because of advantages such as possible selection of wavelengths, adjustable emitting mode and the designable configuration. They still, however, face challenges arising from the low wall plug efficiency and power output. At last, the implementation of the UV-based advanced oxidation processes in controlling biofilms on artificial surfaces is overviewed and their synergistic mechanisms are proposed, which further enlightens the prospective of UV in dealing with the biofilm issue in water infrastructure.
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Affiliation(s)
- Xueru Luo
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen 361005, China
| | - Baoping Zhang
- Department of Electronic Engineering, Laboratory of Micro/Nano-Optoelectronics, Xiamen University, Xiamen, Fujian 361005, China.
| | - Yinghua Lu
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen 361005, China
| | - Yang Mei
- Department of Electronic Engineering, Laboratory of Micro/Nano-Optoelectronics, Xiamen University, Xiamen, Fujian 361005, China
| | - Liang Shen
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, The Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen 361005, China.
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Wang H, Hu C, Shi B. The control of red water occurrence and opportunistic pathogens risks in drinking water distribution systems: A review. J Environ Sci (China) 2021; 110:92-98. [PMID: 34593198 DOI: 10.1016/j.jes.2021.03.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 03/10/2021] [Indexed: 06/13/2023]
Abstract
Many problems in drinking water distribution systems (DWDSs) are caused by microbe, such as biofilm formation, biocorrosion and opportunistic pathogens growth. More iron release from corrosion scales may induce red water. Biofilm played great roles on the corrosion. The iron-oxidizing bacteria (IOB) promoted corrosion. However, when iron-reducing bacteria (IRB) and nitrate-reducing bacteria (NRB) became the main bacteria in biofilm, they could induce iron redox cycling in corrosion process. This process enhanced the precipitation of iron oxides and formation of more Fe3O4 in corrosion scales, which inhibited corrosion effectively. Therefore, the IRB and NRB in the biofilm can reduce iron release and red water occurrence. Moreover, there are many opportunistic pathogens in biofilm of DWDSs. The opportunistic pathogens growth in DWDSs related to the bacterial community changes due to the effects of micropollutants. Micropollutants increased the number of bacteria with antibiotic resistance genes (ARGs). Furthermore, extracellular polymeric substances (EPS) production was increased by the antibiotic resistant bacteria, leading to greater bacterial aggregation and adsorption, increasing the chlorine-resistance capability, which was responsible for the enhancement of the particle-associated opportunistic pathogens in DWDSs. Moreover, O3-biological activated carbon filtration-UV-Cl2 treatment could be used to control the iron release, red water occurrence and opportunistic pathogens growth in DWDSs.
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Affiliation(s)
- Haibo Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chun Hu
- Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Institute of Environmental Research at Greater Bay, Guangzhou University, Guangzhou 510006, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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31
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Shekhawat SS, Kulshreshtha NM, Vivekanand V, Gupta AB. Impact of combined chlorine and UV technology on the bacterial diversity, antibiotic resistance genes and disinfection by-products in treated sewage. BIORESOURCE TECHNOLOGY 2021; 339:125615. [PMID: 34311405 DOI: 10.1016/j.biortech.2021.125615] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/14/2021] [Accepted: 07/16/2021] [Indexed: 06/13/2023]
Abstract
This paper explores the effect of hybrid chlorine and UV disinfection treatment against their individual usage on microbial community, functional genes, antibiotic resistant genes (ARGs) and disinfection by-products (DBPs) formation. The disinfectant doses of 2.5 mg L-1 chlorine and 41 mJ cm-2 UV were selected based on the coliform counts to be attained in treated sewage. The highest bacterial diversity was observed in control (secondary treated) sample followed by UV, chlorine and hybrid disinfection. The highest elimination of bacterial species (296) was achieved in hybrid treatment, which was far better than the standalone treatments. The disinfection with all the disinfectants used resulted in increased abundance of ARGs. Motility genes were found to be enriched in hybrid disinfected samples. DBP concentrations were within the stipulated norms for all the disinfectant treatments used. Hybrid disinfection was observed to be more effective in alleviating the risks associated with the reuse of treated sewage.
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Affiliation(s)
- Sandeep Singh Shekhawat
- Department of Civil Engineering, Malaviya National Institute of Technology, JLN Marg, Jaipur 302017, India
| | - Niha Mohan Kulshreshtha
- Department of Civil Engineering, Malaviya National Institute of Technology, JLN Marg, Jaipur 302017, India
| | - Vivekanand Vivekanand
- Centre for Energy and Environment, Malaviya National Institute of Technology, JLN Marg, Jaipur 302017, India
| | - Akhilendra Bhushan Gupta
- Department of Civil Engineering, Malaviya National Institute of Technology, JLN Marg, Jaipur 302017, India.
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Cao KF, Chen Z, Shi Q, Wu YH, Lu Y, Mao Y, Chen XW, Li K, Xu Q, Hu HY. An insight to sequential ozone‑chlorine process for synergistic disinfection on reclaimed water: Experimental and modelling studies. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 793:148563. [PMID: 34175603 DOI: 10.1016/j.scitotenv.2021.148563] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Abstract
Water reclamation plants (WRPs) are facing the challenges of ensuring microbial safety and require efficient disinfection systems. Sequential ozone‑chlorine disinfection is supposed to be a favorable alternative for reclaimed water disinfection. This study compared the inactivation efficiency of E.coli by single ozone, single chlorine, and sequential ozone‑chlorine disinfection approaches. Notably, a single ozone or chlorine process could only achieve a log removal rate of up to 5 log, whereas the sequential ozone‑chlorine disinfection could completely inactivate microorganisms (7.3 log). For sequential ozone‑chlorine disinfection, the efficiency of chlorination was improved by 2.4%-18.5%. The synergistic effect mainly attributed to the elimination of chlorine consuming substances by ozone. Through the chlorine decay model (CRS) fitting and calculating the integral CT value, the enhancement ability of ozone to chlorine disinfection was quantified. By introducing an enhancement coefficient (β), a succinct and accurate model was established to estimate the inactivation rate of sequential ozone‑chlorine disinfection (mean absolute percentage error: 0.035). The results and methodology of this study are informative to optimize the disinfection units of WRPs.
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Affiliation(s)
- Ke-Fan Cao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China.
| | - Qi Shi
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yin-Hu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yun Lu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yu Mao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Xiao-Wen Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Kuixiao Li
- Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China; Research and Development Center, Beijing Drainage Group Co., Ltd, Beijing 100124, PR China
| | - Qi Xu
- Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China; Research and Development Center, Beijing Drainage Group Co., Ltd, Beijing 100124, PR China
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Jiangsu, Suzhou, 215163, PR China.
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Huo L, Zhao S, Shi B, Wang H, He S. Bacterial community change and antibiotic resistance promotion after exposure to sulfadiazine and the role of UV/H 2O 2-GAC treatment. CHEMOSPHERE 2021; 283:131214. [PMID: 34147982 DOI: 10.1016/j.chemosphere.2021.131214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 06/05/2021] [Accepted: 06/10/2021] [Indexed: 06/12/2023]
Abstract
Effects of sulfadiazine on bacterial community and antibiotic resistance genes (ARGs) in drinking water distribution systems (DWDSs) were investigated in this study. Three DWDSs, including sand filtered (SF) DWDSs, granular active carbon (GAC) filtration DWDSs, and UV/H2O2-GAC DWDSs, were used to deliver sand filtered water, GAC filtered water, and UV/H2O2-GAC treated water, respectively. UV/H2O2-GAC filtration can remove the dissolved organic matter effectively, which resulted in the lowest bacterial diversity, biomass and ARGs in effluents and biofilm of DWDSs. When sulfadiazine was added to the sand filtered water, the dehydrogenase concentration and bacterial activity of bacterial community increased in effluents and biofilm of different DWDSs, inducing more extracellular polymeric substances (EPS) production. The proteins increasement percentage was 26.9%, 11.7% and 19.1% in biofilm of three DWDSs, respectively. And the proteins increased to 830.30 ± 20.56 μg cm-2, 687.04 ± 18.65 μg cm-2 and 586.07 ± 16.24 μg cm-2, respectively. The increase of EPS promoted biofilm formation and increased the chlorine-resistance capability of bacteria. Therefore, the relative abundance of Clostridium_sensu_stricto_1 increased to 12.22%, 10.41% and 0.33% in biofilm of the three DWDSs, respectively. Candidatus_Odyssella also increased in the effluents and biofilm of the three DWDSs. These antibiotic resistance bacteria increase in DWDSs also induced the ARGs promotion, including sul1, sul2, sul3, mexA and class 1 integrons (int1). However, UV/H2O2-GAC filtration induced the lowest increase of dehydrogenase and EPS production through sulfadiazine removal efficiently, resulting in the least bacterial community change and ARGs promotion in UV/H2O2-GAC DWDSs.
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Affiliation(s)
- Lixin Huo
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Shehang Zhao
- Qingdao University of Technology, Qingdao, 266033, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Haibo Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Shouyang He
- Key Laboratory of Karst Georesources and Environment, Ministry of Education, Guizhou University, Guiyang, 550025, China
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Wang HB, Wu YH, Luo LW, Yu T, Xu A, Xue S, Chen GQ, Ni XY, Peng L, Chen Z, Wang YH, Tong X, Bai Y, Xu YQ, Hu HY. Risks, characteristics, and control strategies of disinfection-residual-bacteria (DRB) from the perspective of microbial community structure. WATER RESEARCH 2021; 204:117606. [PMID: 34500181 PMCID: PMC8390064 DOI: 10.1016/j.watres.2021.117606] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 08/19/2021] [Accepted: 08/23/2021] [Indexed: 05/19/2023]
Abstract
The epidemic of COVID-19 has aroused people's particular attention to biosafety. A growing number of disinfection products have been consumed during this period. However, the flaw of disinfection has not received enough attention, especially in water treatment processes. While cutting down the quantity of microorganisms, disinfection processes exert a considerable selection effect on bacteria and thus reshape the microbial community structure to a great extent, causing the problem of disinfection-residual-bacteria (DRB). These systematic and profound changes could lead to the shift in regrowth potential, bio fouling potential, as well as antibiotic resistance level and might cause a series of potential risks. In this review, we collected and summarized the data from the literature in recent 10 years about the microbial community structure shifting of natural water or wastewater in full-scale treatment plants caused by disinfection. Based on these data, typical DRB with the most reporting frequency after disinfection by chlorine-containing disinfectants, ozone disinfection, and ultraviolet disinfection were identified and summarized, which were the bacteria with a relative abundance of over 5% in the residual bacteria community and the bacteria with an increasing rate of relative abundance over 100% after disinfection. Furthermore, the phylogenic relationship and potential risks of these typical DRB were also analyzed. Twelve out of fifteen typical DRB genera contain pathogenic strains, and many were reported of great secretion ability. Pseudomonas and Acinetobacter possess multiple disinfection resistance and could be considered as model bacteria in future studies of disinfection. We also discussed the growth, secretion, and antibiotic resistance characteristics of DRB, as well as possible control strategies. The DRB phenomenon is not limited to water treatment but also exists in the air and solid disinfection processes, which need more attention and more profound research, especially in the period of COVID-19.
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Affiliation(s)
- Hao-Bin Wang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yin-Hu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China.
| | - Li-Wei Luo
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Tong Yu
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266000, PR China
| | - Ao Xu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Suzhou Jiangsu 215163, PR China
| | - Song Xue
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Gen-Qiang Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Xin-Ye Ni
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Lu Peng
- Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Shenzhen 518055, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yun-Hong Wang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Xin Tong
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yuan Bai
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yu-Qing Xu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Room 524, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China; Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Shenzhen 518055, PR China.
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The role of Acanthamoeba spp. in biofilm communities: a systematic review. Parasitol Res 2021; 120:2717-2729. [PMID: 34292376 DOI: 10.1007/s00436-021-07240-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 07/01/2021] [Indexed: 12/16/2022]
Abstract
Acanthamoeba spp. have always caused disease in immunosuppressed patients, but since 1986, they have become a worldwide public health issue by causing infection in healthy contact lens wearers. Amoebae of the Acanthamoeba genus are broadly distributed in nature, living either freely or as parasites, and are frequently associated with biofilms throughout the environment. These biofilms provide the parasite with protection against external aggression, thus favoring its increased pathogeny. This review aims to assess observational studies on the association between Acanthamoeba spp. and biofilms, opening potential lines of research on this severe ocular infection. A systematic literature search was conducted in May 2020 in the following databases: PubMed Central®/Medline, LILACS, The Cochrane Library, and EMBASE®. The studies were selected following the inclusion and exclusion criteria specifically defined for this review. Electronic research recovered 353 publications in the literature. However, none of the studies met the inclusion criterion of biofilm-producing Acanthamoeba spp., inferring that the parasite does not produce biofilms. Nonetheless, 78 studies were classified as potentially included regarding any association of Acanthamoeba spp. and biofilms. These studies were allocated across six different locations (hospital, aquatic, ophthalmic and dental environments, biofilms produced by bacteria, and other places). Acanthamoeba species use biofilms produced by other microorganisms for their benefit, in addition to them providing protection to and facilitating the dissemination of pathogens residing in them.
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Wang L, Ye C, Guo L, Chen C, Kong X, Chen Y, Shu L, Wang P, Yu X, Fang J. Assessment of the UV/Chlorine Process in the Disinfection of Pseudomonas aeruginosa: Efficiency and Mechanism. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:9221-9230. [PMID: 34138551 DOI: 10.1021/acs.est.1c00645] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
UV irradiation and chlorination have been widely used for water disinfection. However, there are some limitations, such as the risk of generating viable but nonculturable bacteria and bacteria reactivation when using UV irradiation or chlorination alone. This study comprehensively evaluated the feasibility of the UV/chlorine process in drinking water disinfection, and Pseudomonas aeruginosa was selected as the target microorganism. The number of culturable cells was effectively reduced by more than 5 orders of magnitude (5-log10) after UV, chlorine, and UV/chlorine treatments. However, intact and VBNC cells were detected at 103 to 104 cells/mL after UV and chlorine treatments, whereas they were undetectable after UV/chlorine treatment due to the primary contribution of reactive chlorine species (Cl•, Cl2•-, and ClO•). After UV/chlorine treatment, the metabolic activity determined using single cell Raman spectroscopy was much lower than that after UV. The level of toxic opr gene in P. aeruginosa decreased by more than 99% after UV/chlorine treatment. Importantly, bacterial dark reactivation was completely suppressed by UV/chlorine treatment but not UV or chlorination. This study suggests that the UV/chlorine treatment can completely damage bacteria and is promising for pathogen inactivation to overcome the limitations of UV and chlorine treatments alone.
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Affiliation(s)
- Liping Wang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Chengsong Ye
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, P. R. China
| | - Lizheng Guo
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, P. R. China
| | - Chunyan Chen
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Xiujuan Kong
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Yaoqing Chen
- School of Public Health, Shenzhen, Sun Yat-Sen University, Shenzhen 510000, P. R. China
| | - Longfei Shu
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Peng Wang
- Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Kowloon 999077, Hong Kong, P.R. China
| | - Xin Yu
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, P. R. China
| | - Jingyun Fang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
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Jing Z, Lu Z, Mao T, Cao W, Wang W, Ke Y, Zhao Z, Wang X, Sun W. Microbial composition and diversity of drinking water: A full scale spatial-temporal investigation of a city in northern China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 776:145986. [PMID: 33640542 DOI: 10.1016/j.scitotenv.2021.145986] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/15/2021] [Accepted: 02/15/2021] [Indexed: 06/12/2023]
Abstract
The microbiological water quality of drinking water distribution systems (DWDSs) is of primary importance for public health. The detachment of biofilm attached on the pipe wall attribution to water source switch and the occurrence of potentially pathogenic chlorine-resistant bacteria (CRB) under chlorine disinfection get lots of attention. Studies examining microbial communities after the water source switch, particularly in low-salinity water, have been scant. The UV‑chlorine combined disinfection applied in one of the investigated drinking water plants provided insight into the control of CRBs. We applied high-throughput sequencing of the 16S rRNA gene to characterize the bacterial communities of the DWDS in northern China over 1 year. A network comprising four different DWDSs was sampled at 48 sites every season (temperate continental monsoon climate), and the impact of key spatial-temporal and physicochemical parameters was investigated. Overall, the entire bacterial community was not significantly different among the four DWDSs (spatial parameter) but varied with seasons (temporal parameter). The switch in water sources might increase the relative abundance of potentially opportunistic pathogens in DWDSs. UV‑chlorine combined disinfection can decrease community diversity and is likely to control the growth of potential opportunistic pathogens in DWDSs.
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Affiliation(s)
- Zibo Jing
- School of Environment, Tsinghua University, Beijing 100084, China; Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Zedong Lu
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Ted Mao
- Research Institute for Environmental Innovation (Suzhou) Tsinghua, Suzhou 215163, China; MW Technologies, Inc., London, Ontario, Canada
| | - Wenfeng Cao
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Weibo Wang
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Yanchu Ke
- School of Environment, Tsinghua University, Beijing 100084, China; State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Zhinan Zhao
- School of Environment, Tsinghua University, Beijing 100084, China; Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Xiaohui Wang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
| | - Wenjun Sun
- School of Environment, Tsinghua University, Beijing 100084, China; Research Institute for Environmental Innovation (Suzhou) Tsinghua, Suzhou 215163, China.
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Calero Preciado C, Boxall J, Soria-Carrasco V, Martínez S, Douterelo I. Implications of Climate Change: How Does Increased Water Temperature Influence Biofilm and Water Quality of Chlorinated Drinking Water Distribution Systems? Front Microbiol 2021; 12:658927. [PMID: 34168627 PMCID: PMC8217620 DOI: 10.3389/fmicb.2021.658927] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 05/04/2021] [Indexed: 01/04/2023] Open
Abstract
Temperature variation can promote physico-chemical and microbial changes in the water transported through distribution systems and influence the dynamics of biofilms attached to pipes, thus contributing to the release of pathogens into the bulk drinking water. An experimental real-scale chlorinated DWDS was used to study the effect of increasing temperature from 16 to 24°C on specific pathogens, bacterial-fungal communities (biofilm and water samples) and determine the risk of material accumulation and mobilisation from the pipes into the bulk water. Biofilm was developed for 30 days at both temperatures in the pipe walls, and after this growth phase, a flushing was performed applying 4 gradual steps by increasing the shear stress. The fungal-bacterial community characterised by Illumina MiSeq sequencing, and specific pathogens were studied using qPCR: Mycobacterium spp., Mycobacterium avium complex, Acanthamoeba spp., Pseudomonas aeruginosa, Legionella pneumophilia, and Stenotrophomonas maltophilia. Sequencing data showed that temperature variation significantly modified the structure of biofilm microbial communities from the early stages of biofilm development. Regarding bacteria, Pseudomonas increased its relative abundance in biofilms developed at 24°C, while fungal communities showed loss of diversity and richness, and the increase in dominance of Fusarium genus. After the mobilisation phase, Pseudomonas continued being the most abundant genus at 24°C, followed by Sphingobium and Sphingomonas. For biofilm fungal communities after the mobilisation phase, Helotiales incertae sedis and Fusarium were the most abundant taxa. Results from qPCR showed a higher relative abundance of Mycobacterium spp. on day 30 and M. avium complex throughout the growth phase within the biofilms at higher temperatures. The temperature impacts were not only microbial, with physical mobilisation showing higher discolouration response and metals release due to the increased temperature. While material accumulation was accelerated by temperature, it was not preferentially to either stronger or weaker biofilm layers, as turbidity results during the flushing steps showed. This research yields new understanding on microbial challenges that chlorinated DWDS will undergo as global temperature rises, this information is needed in order to protect drinking water quality and safety while travelling through distribution systems.
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Affiliation(s)
- Carolina Calero Preciado
- Department of Civil and Structural Engineering, Sheffield Water Centre, The University of Sheffield, Sheffield, United Kingdom.,NERC Biomolecular Analysis Facility, Department of Animal and Plant Sciences, The University of Sheffield, Sheffield, United Kingdom
| | - Joby Boxall
- Department of Civil and Structural Engineering, Sheffield Water Centre, The University of Sheffield, Sheffield, United Kingdom
| | - Víctor Soria-Carrasco
- Department of Animal and Plant Sciences, The University of Sheffield, Sheffield, United Kingdom
| | - Soledad Martínez
- Área de Microbiología, Departamento de Biociencias, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - Isabel Douterelo
- Department of Civil and Structural Engineering, Sheffield Water Centre, The University of Sheffield, Sheffield, United Kingdom
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Causes, Factors, and Control Measures of Opportunistic Premise Plumbing Pathogens—A Critical Review. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11104474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This review critically analyses the chemical and physical parameters that influence the occurrence of opportunistic pathogens in the drinking water distribution system, specifically in premise plumbing. A comprehensive literature review reveals significant impacts of water age, disinfectant residual (type and concentration), temperature, pH, and pipe materials. Evidence suggests that there is substantial interplay between these parameters; however, the dynamics of such relationships is yet to be elucidated. There is a correlation between premise plumbing system characteristics, including those featuring water and energy conservation measures, and increased water quality issues and public health concerns. Other interconnected issues exacerbated by high water age, such as disinfectant decay and reduced corrosion control efficiency, deserve closer attention. Some common features and trends in the occurrence of opportunistic pathogens have been identified through a thorough analysis of the available literature. It is proposed that the efforts to reduce or eliminate their incidence might best focus on these common features.
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Ekundayo TC, Igwaran A, Oluwafemi YD, Okoh AI. Global bibliometric meta-analytic assessment of research trends on microbial chlorine resistance in drinking water/water treatment systems. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 278:111641. [PMID: 33221673 DOI: 10.1016/j.jenvman.2020.111641] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 11/03/2020] [Accepted: 11/04/2020] [Indexed: 06/11/2023]
Abstract
Chlorine is the commonest and cheapest disinfectant used in drinking water and wastewater treatment at household, municipal and industrial levels. However, the uprising of microbial chlorine resistance (MCR) pose critical public health hazard concerns; because, its potentiate exposure to difficult-to-treat resistant pathogens. Therefore, this study aimed at evaluating the burden of MCR in drinking water/wastewater treatment and distribution systems (DWWTDS) via science mapping of research productivity (authors, countries, institutions), thematic conceptual framework, disciplines, research networks and associated intellectual landscape. MCR data were mined from Scopus and Web of Science based on optimized algorithms with the root key term "chlorine* resistant*'' and analysed for pre-set indicator variables. Results revealed 1127 documents from 442 journals and 1430% average growth rate (AGR) of research articles from 2017 to 2019 on MCR. Country-wise, the USA (n = 299), China (n = 119), and Japan (n = 43) ranked in the 1st, 2nd, and 3rd positions respectively, among the top participating countries in MCR research. MCR research had considerable performance in public health and sustainable concern subjects namely, Environmental Sciences & Ecology, Engineering, Microbiology, Water Resources, Biotechnology & Applied Microbiology, Food Science & Technology, Public, Environ & Occupational Health, Chemistry, Infectious Diseases, and Marine & Freshwater Biology; and with noticeable AGR in Environmental Sciences & Ecology (330%) and Infectious Diseases (130%). The study found biofilm-related thrusts (n = 90, 270% AGR) as main research hotspots on MCR. Overall, the study identified and discussed four important thematic areas of public health challenges in MCR that could promote increasing waterborne diseases due to (re)emerging pathogens, enteric viruses and dissemination in DWWTDS. In conclusion, this study provides comprehensive overview of the growing burden of MCR in DWWTDS and standout as a primer of information for researchers on MCR. It recommends direct, intentional and integrated research priorities on MCR to overcome accompanying public health and environmental threats. In addition, chlorine resistance in waterborne fungi have not received research attention. Research activities related to fungal chlorine resistance will be an invaluable future direction in DWWTDS and guide against exposure to waterborne pathogenic fungi and mycotoxins. It is unknown whether chlorine resistance can be acquired by horizontal gene transfer in microorganisms and future research should elucidate this important thrust.
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Affiliation(s)
- Temitope C Ekundayo
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice 5700, Eastern Cape, South Africa; Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice 5700, Eastern Cape, South Africa; Department of Biological Sciences, University of Medical Sciences, Ondo City PMB 536, Ondo State, Nigeria.
| | - Aboi Igwaran
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice 5700, Eastern Cape, South Africa; Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice 5700, Eastern Cape, South Africa
| | - Yinka D Oluwafemi
- Department of Biological Sciences, University of Medical Sciences, Ondo City PMB 536, Ondo State, Nigeria
| | - Anthony I Okoh
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice 5700, Eastern Cape, South Africa; Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice 5700, Eastern Cape, South Africa
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41
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Li N, Li X, Shi ZY, Fan XY, Zhou ZW. Response of high-, mid- and low-abundant taxa and potential pathogens to eight disinfection methods and their interactions in domestic hot water system. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 749:141440. [PMID: 32829270 DOI: 10.1016/j.scitotenv.2020.141440] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/29/2020] [Accepted: 07/31/2020] [Indexed: 06/11/2023]
Abstract
Eight disinfection methods were applied to control biofilm contamination in domestic hot water system. The inactivation efficiency, responses of high- (≥1%), mid- (0.1% ~ 1%) and low-abundant taxa (≤0.1%) to disinfection, and interactions within and across three sub-communities were investigated. Ultraviolet was the most effective disinfection method for total bacteria and Escherichia coli, and chlorine dioxide had the highest inactivation efficiency on heterotrophic bacteria, while silver ions exhibited poor performance on all of them. At the phylum level, the responses of microorganisms to eight disinfection methods were different, but Proteobacteria and Firmicutes dominated in most samples. Eight disinfection methods had a greater impact on the proportion of high- and mid-abundant taxa than that of low-abundant taxa, and led to dissimilar transformations of genera among high-, mid- and low-abundant taxa in each sample. High-, mid- and low-abundant taxa of different samples showed similar structures and were roughly clustered into three Groups. Moreover, high-abundant taxa had more complex internal interactions than mid- and low-abundant taxa, and mainly presented co-occurrence patterns. The associations between high- and low-abundant taxa were close, and some low-abundant genera were identified as hub bacteria, such as Paracoccus, Thioalkalispira and Flavitalea. Furthermore, a total of 23 potential pathogens were detected in this study, and they mainly showed positive interactions, with Mycobacteria and Streptococcus as keystone genera. These results highlight the dissimilar responses of high-, mid- and low-abundant taxa to disinfection, and the critical role of some low-abundant genera in the microbial network, as well as the co-occurrence patterns among potential pathogens.
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Affiliation(s)
- Na Li
- College of Architecture and Civil Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Xing Li
- College of Architecture and Civil Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Zhi-Yuan Shi
- Shanghai Investigation, Design & Research Institute Co., Ltd, Shanghai 200335, PR China
| | - Xiao-Yan Fan
- College of Architecture and Civil Engineering, Beijing University of Technology, Beijing 100124, PR China.
| | - Zhi-Wei Zhou
- College of Architecture and Civil Engineering, Beijing University of Technology, Beijing 100124, PR China
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Wang H, Wang J, Li S, Ding G, Wang K, Zhuang T, Huang X, Wang X. Synergistic effect of UV/chlorine in bacterial inactivation, resistance gene removal, and gene conjugative transfer blocking. WATER RESEARCH 2020; 185:116290. [PMID: 32818733 DOI: 10.1016/j.watres.2020.116290] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 07/19/2020] [Accepted: 08/09/2020] [Indexed: 05/21/2023]
Abstract
Antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) were investigated from effluent of two hospital and two municipal wastewater treatment plants (WWTPs) before and after disinfection. The results of network analysis showed that 8 genera were identified to be the main potential hosts of ARGs, including Mycobacterium, Ferruginibacter, Thermomonas, Morganella, Enterococcus, Bacteroides, Myroides and Romboutsia. The removal of ARGs and their possible bacterialhosts were synchronous and consistent by chlorine or ultraviolet (UV) disinfection in WWTPs. The mechanisms of ARB and ARGs removal, and conjugation transfer of RP4 plasmids by UV, chlorine and synergistic UV/chlorine disinfection was revealed. Compared to UV alone, ARB inactivation was improved 1.4 log and photoreactivation was overcomeeffectively by UV/chlorine combination (8 mJ/cm2, chlorine 2 mg/L). However, ARGs degradation was more difficult than ARB inactivation. Until UV dosage enhanced to 320 mJ/cm2, ARGs achieved 0.58-1.60 log removal. Meanwhile, when 2 mg/L of chlorine was combined with UV combination, ARGs removal enhanced 1-1.5 log. The synergistic effect of adding low-dose chlorine (1-2 mg/L) during UV radiation effectively improved ARB and ARGs removal simultaneously. The same synergistic effect also occurred in the horizontal gene transfer (HGT). Non-lethal dose chlorine (0.5 mg/L) increased the conjugation transfer frequency,which confirmed that the mRNA expression levels of type IV secretion system (T4SS) proteins vir4D, vir5B and vir10B were significantly enhanced. The risk of RP4 plasmid conjugation transfer was significantly reduced with UV/chlorine (UV ≥ 4 mJ/cm2, chlorine ≥ 1 mg/L). These findings may serve as valuable implications for assessing and controlling the risk of ARGs transfer and propagation in the environment.
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Affiliation(s)
- Haichao Wang
- Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China
| | - Jin Wang
- Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China.
| | - Shuming Li
- Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China
| | - Guoyu Ding
- Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China
| | - Kun Wang
- Jinan Environmental Research Academy, Jinan, Shandong 250102, China
| | - Tao Zhuang
- Jinan Environmental Research Academy, Jinan, Shandong 250102, China
| | - Xue Huang
- Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China
| | - Xiaoyue Wang
- Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China
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43
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Zhao L, Liu YW, Li N, Fan XY, Li X. Response of bacterial regrowth, abundant and rare bacteria and potential pathogens to secondary chlorination in secondary water supply system. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 719:137499. [PMID: 32120107 DOI: 10.1016/j.scitotenv.2020.137499] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 02/18/2020] [Accepted: 02/20/2020] [Indexed: 06/10/2023]
Abstract
This study investigated the effects of secondary chlorination on bacterial regrowth, microbial communities (abundant and rare taxa) and bacterial functions of pipe wall biofilm and bulk water in simulated secondary water supply system (SWSS). Continuous secondary chlorination was more effective than short-term secondary chlorination to control the bacterial regrowth in both biofilm and water samples. Bacterial diversity slightly reduced after continuous secondary chlorination, and 19.27% of the total operational taxonomic units (OTUs) were shared by biofilm and water samples, with Bacillus as the dominant genus. Abundant and rare taxa exhibited different community structures. Proteobacteria and candidate division WPS-1 predominated in abundant and rare phyla were sensitive to chlorine, while Firmicutes, Acidobacteria and Bacteroidetes, exhibited relative strong chlorine resistance. The abundant genera in control sample (e.g., Bosea, Sphingobium and Gemmata) exhibited poor tolerance to chlorine, while Bacillus in biofilm and Defluviimonas in water were the main chlorine-resistant genera. Moreover, the composition of rare genera in each sample was obviously different. Furthermore, a total of 18 potential pathogens were detected with Pseudomonas as the dominant genus, most of which were significantly reduced after disinfection. There were mainly positive interactions among potential pathogenic bacteria, with Enterococcus, Legionella and Vibrio as the hub genera as revealed by network analysis. Similar bacterial functions in both biofilm and water were observed with metabolism as the predominant bacterial function, while, human disease function only accounted for 1.07% of bacterial functions. These results highlighted the importance of continuous secondary chlorination for controlling biosafety of SWSS and identified the dissimilar responses of abundant and rare bacteria to the disinfection, as well as the co-occurrence patterns among potential pathogens, improving our understanding of bacterial communities in SWSS.
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Affiliation(s)
- Li Zhao
- China Architecture Design and Research Group, Beijing 100044, PR China
| | - Yong-Wang Liu
- China Architecture Design and Research Group, Beijing 100044, PR China; College of Architecture and Civil engineering, Beijing University of Technology, Beijing 100124, PR China.
| | - Na Li
- College of Architecture and Civil engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Xiao-Yan Fan
- College of Architecture and Civil engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Xing Li
- College of Architecture and Civil engineering, Beijing University of Technology, Beijing 100124, PR China
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44
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Analysis of microbial contamination of household water purifiers. Appl Microbiol Biotechnol 2020; 104:4533-4545. [PMID: 32193577 DOI: 10.1007/s00253-020-10510-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 02/13/2020] [Accepted: 02/28/2020] [Indexed: 12/19/2022]
Abstract
Household water purifiers are increasingly used to treat drinking water at the household level, but their influence on the microbiological safety of drinking water has rarely been assessed. In this study, representative purifiers, based on different filtering processes, were analyzed for their impact on effluent water quality. The results showed that purifiers reduced chemical qualities such as turbidity and free chlorine. However, a high level of bacteria (102-106 CFU/g) was detected at each stage of filtration using a traditional culture-dependent method, whereas quantitative PCR with propidium monoazide (PMA) treatment showed 106-108 copies/L of total viable bacteria in effluent water, indicating elevated microbial contaminants after purifiers. In addition, high-throughput sequencing revealed a diverse microbial community in effluents and membranes. Proteobacteria (22.06-97.42%) was the dominant phylum found in all samples, except for purifier B, in which Melainabacteria was most abundant (65.79%). For waterborne pathogens, Escherichia coli (100-106 copies/g) and Pseudomonas aeruginosa (100-105 copies/g) were frequently detected by qPCR. Sequencing also demonstrated the presence of E. coli (0-6.26%), Mycobacterium mucogenicum (0.01-3.46%), and P. aeruginosa (0-0.16%) in purifiers. These finding suggest that water from commonly used household purifiers still impose microbial risks to human health.
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45
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Cui Q, Liu H, Yang HW, Lu Y, Chen Z, Hu HY. Bacterial removal performance and community changes during advanced treatment process: A case study at a full-scale water reclamation plant. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 705:135811. [PMID: 31837874 DOI: 10.1016/j.scitotenv.2019.135811] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 11/25/2019] [Accepted: 11/26/2019] [Indexed: 06/10/2023]
Abstract
Advanced treatment is of great significance to water reclamation and reuse, which can improve water quality, control microbial risks and guarantee the safety of water reuse. This study evaluates the microbial quantity and bacterial community dynamics during advanced wastewater treatment and reuse processes (i.e. denitrification biofilter (DNBF), ultrafiltration (UF), ozonation, ultraviolet (UV) disinfection) at a large-scale water reclamation plant. It is found that different treatment processes had significant influence on the cultivability of total bacteria and the log reduction values of fecal coliform at DNBF, UF, ozonation and UV are calculated as 0.38, 2.46, 0.38 and 1.63 respectively. Moreover, the bacterial diversity in the treatment process showed apparent spatial differences, among which the effluent from ozonation process had the lowest bacterial diversity. Sequencing analysis indicated the existence of pathogenic bacterium such as Arcobacter, Bacteroides and Pseudomonas in the secondary effluent. Notably, Pseudomonas remained the most dominant species (relative abundance 41.9% in UV effluent) in reclaimed water after advanced treatment processes, which calls for high attention to sustainable water reuse. In order to inhibit bacterial regrowth in the storage tank, chlorine disinfection is recommended to improve the continuous disinfection capability of the system.
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Affiliation(s)
- Qi Cui
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Hai Liu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Hong-Wei Yang
- Research Institute for Environmental Innovation (Suzhou), Tsinghua University, Suzhou 215163, PR China
| | - Yun Lu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China.
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Shenzhen 518055, PR China.
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46
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Zhu Y, Chen L, Xiao H, Shen F, Deng S, Zhang S, He J, Song C, Wang X, Zhang J, Gong L, Hu C. Effects of disinfection efficiency on microbial communities and corrosion processes in drinking water distribution systems simulated with actual running conditions. J Environ Sci (China) 2020; 88:273-282. [PMID: 31862068 DOI: 10.1016/j.jes.2019.09.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 09/09/2019] [Accepted: 09/10/2019] [Indexed: 06/10/2023]
Abstract
The effects of disinfection efficiency on microbial communities and the corrosion of cast iron pipes in drinking water distribution systems (DWDSs) were studied. Two annular reactors (ARs) that simulated actual running conditions with UV/Cl2 disinfection and chlorination alone were used. High chlorine consumption and corrosion rate were found in the AR with UV/Cl2. According to functional genes and pyrosequencing tests, a high percentage of iron recycling bacteria was detected within the biofilm of the AR with Cl2 at early running stage, whereas siderophore-producing bacteria were dominant in the biofilm of the AR with UV/Cl2. At the early running stage, the sequential use of UV light and an initial high chlorine dosage suppressed the biomass and iron-recycling bacteria in both bulk water and biofilms, thereby forming less protective scales against further corrosion, which enhanced chlorine consumption. Non-metric multidimensional scaling analysis showed that the bacterial communities in the ARs shaped from within rather than being imported by influents. These results indicate that the initial high disinfection efficiency within the distribution system had not contributed to the accumulation of iron-recycling bacteria at the early running stages. This study offer certain implications for controlling corrosion and water quality in DWDSs.
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Affiliation(s)
- Ying Zhu
- Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, China; Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
| | - Lu Chen
- College of Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Hong Xiao
- College of Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Fei Shen
- Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, China; Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Shihuai Deng
- Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, China; Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Shirong Zhang
- College of Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Jinsong He
- Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, China; Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Chun Song
- Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, China; Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Xie Wang
- Soil and Fertilizer Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan 610066, China; Key Laboratory of Agricultural Environment of Southwest China, Ministry of Agriculture and Rural Affairs, Chengdu, Sichuan 610066, China
| | - Jianhua Zhang
- Soil and Fertilizer Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan 610066, China; Key Laboratory of Agricultural Environment of Southwest China, Ministry of Agriculture and Rural Affairs, Chengdu, Sichuan 610066, China
| | - Li Gong
- College of Forestry, Sichuan Agricultural University, Chengdu, Sichuan 611130, China
| | - Chun Hu
- Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Institute of Environmental Research at Greater Bay, Guangzhou University, Guangzhou, Guangdong 510006, China.
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47
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Cerreta G, Roccamante MA, Plaza-Bolaños P, Oller I, Aguera A, Malato S, Rizzo L. Advanced treatment of urban wastewater by UV-C/free chlorine process: Micro-pollutants removal and effect of UV-C radiation on trihalomethanes formation. WATER RESEARCH 2020; 169:115220. [PMID: 31677437 DOI: 10.1016/j.watres.2019.115220] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 09/22/2019] [Accepted: 10/19/2019] [Indexed: 06/10/2023]
Abstract
The effect of the UV-C/free chlorine (FC) process on the removal of contaminants of emerging concern (CECs) from real urban wastewater as well as the effect of UV-C radiation on the formation of trihalomethanes (THMs) compared to FC process alone was investigated. Unlike of FC process, UV-C/FC was really effective in the degradation of the target CECs (carbamazepine (CBZ), diclofenac, sulfamethoxazole and imidacloprid) in real wastewater (87% degradation of total CECs within 60 min, QUVC = 1.33 kJ L-1), being CBZ the most refractory one (49.5%, after 60 min). The UV-C radiation significantly affected the formation of THMs. THMs concentration (mainly chloroform) was lower in UV-C/FC process after 30 min treatment (<1 μgL-1 = limit of quantification (LOQ)) than in FC process in dark (2.3 μgL-1). Noteworthy, while in FC treated wastewater chloroform concentration increased after treatment, UV-C/FC process resulted in a significant decrease (residual concentrations below the LOQ), even after 24 h and 48 h post-treatment incubation. The formation of radicals due to UV-C/FC process can reduce THMs compared to chlorination process, because part of FC reacts with UV-C radiation to form radicals and it is no longer available to form THMs. These results are encouraging in terms of possible use of UV-C/FC process as advanced treatment of urban wastewater even for possible effluent reuse.
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Affiliation(s)
- Giusy Cerreta
- Department of Civil Engineering, University of Salerno, Via Giovanni Paolo II 132, 84084, Fisciano, SA, Italy
| | - Melina A Roccamante
- Plataforma Solar de Almería-CIEMAT, Ctra. Senés km 4, 04200, Tabernas, Almería, Spain; CIESOL, Joint Centre of the University of Almería-CIEMAT, 04120, Almería, Spain
| | | | - Isabel Oller
- Plataforma Solar de Almería-CIEMAT, Ctra. Senés km 4, 04200, Tabernas, Almería, Spain; CIESOL, Joint Centre of the University of Almería-CIEMAT, 04120, Almería, Spain
| | - Ana Aguera
- CIESOL, Joint Centre of the University of Almería-CIEMAT, 04120, Almería, Spain
| | - Sixto Malato
- Department of Civil Engineering, University of Salerno, Via Giovanni Paolo II 132, 84084, Fisciano, SA, Italy; Plataforma Solar de Almería-CIEMAT, Ctra. Senés km 4, 04200, Tabernas, Almería, Spain.
| | - Luigi Rizzo
- Department of Civil Engineering, University of Salerno, Via Giovanni Paolo II 132, 84084, Fisciano, SA, Italy.
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Linden KG, Hull N, Speight V. Thinking Outside the Treatment Plant: UV for Water Distribution System Disinfection. Acc Chem Res 2019; 52:1226-1233. [PMID: 31038919 DOI: 10.1021/acs.accounts.9b00060] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
This work critically evaluates the current paradigm of water distribution system management and juxtaposes that with the potential benefits of employing UV irradiation, which we hope will catalyze a judicial re-evaluation of the current practices in water distribution system management and spur critical research and a new way of thinking about secondary disinfection across the extent of distribution systems. Given the recent advances in UV technology and the efficacy of UV disinfection against all pathogen classes, we now see UV applications for disinfection in many aspects of consumers lives: in water coolers, dishwashers, coffee makers, and disinfection of personal items like gym bags, water bottles, and toothbrushes. Public and regulatory concern over water quality and pathogens, especially the recent interest in building plumbing, calls out for new approaches to disinfection and distribution system management. We envision a new model for secondary disinfection in water distribution systems utilizing emerging germicidal UV LED-based disinfection. UV irradiation in water treatment can achieve high levels of disinfection of all pathogens and minimize or eliminate the formation of regulated disinfection byproducts. So why is UV not considered as a secondary disinfectant for distribution systems? In this Account, we lay out the logic as to the benefits and practicality of adding distributed UV treatment to assist in protection of distribution systems and protect water quality for human exposure. The possible locations of UV irradiation in distribution systems are envisioned, potentially including UV booster stations along the distribution network, UV in storage tanks or their inlet/outlets, LEDs distributed along pipe walls, small point of use/entry treatment systems for buildings/homes/taps, or submersible swimming or rolling UV LED drones to reach problem pipes and provide a "shock" treatment or provide sterilization after main breaks or repairs. The benefits of UV applications in water also include high effectiveness against chlorine-resistant protozoa, no added disinfection byproducts, and compatibility of adding of UV to existing secondary disinfection strategies for enhanced protection. Potential challenges and research needs are described, such as use of UV-compatible pipe materials, implementation of sensors to monitor distributed LEDs, management of waste heat from the rear surface of the LED, and understanding the potential for regrowth of opportunistic microorganisms. Another notable challenge is the relatively stagnant regulatory environment in some countries to develop frameworks for evaluation and acceptance of UV technology in distribution systems that require a chemical secondary disinfectant. Rapid advances in UV LED research has propelled the growth of this field, but needs still remain, including understanding behavior of biofilms in pipes under UV irradiation, including any beneficial effects that may be lost, the potential for fouling of LED emission surfaces and monitoring points, and provision of a distributed power network to run the LEDs. Regulators may want specific monitoring approaches and advances in real-time monitoring of microbial viability, and engineers may need to develop new approaches to overall management.
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Affiliation(s)
- Karl G. Linden
- University of Colorado Boulder, Civil, Environmental and Architectural Engineering, Boulder, Colorado 80309, United States
| | - Natalie Hull
- The Ohio State University, Department of Civil, Environmental, and Geodedic Engineering, Columbus, Ohio 43210, United States
| | - Vanessa Speight
- University of Sheffield, Department of Civil and Structural Engineering, University of Sheffield, Sheffield, S1 3JD U.K
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