1
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Ma D, Belloni C, Hull NM. Innovative microbial water quality management in water distribution systems using in-pipe hydropowered UV disinfection: envisioning futuristic water-energy systems. ENVIRONMENTAL TECHNOLOGY 2024:1-17. [PMID: 39010788 DOI: 10.1080/09593330.2024.2375008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 06/14/2024] [Indexed: 07/17/2024]
Abstract
Hydropower UV disinfection has not been explored as a possible alternative for off-grid disinfection. Hydropowered UV LED technology was developed using off-the-shelf UV-C LEDs and pico - and femto-scale hydro turbine generators and evaluated across point-of-use relevant flow rates. Commercially available UV LED flow through reactors were subjected to microorganism challenge testing with 3 power schemes: wall-plug, hydropower, and hydropower-charged battery. UV LEDs powered by hydropower-charged battery demonstrated similar disinfection as wall-plug powered UV LEDs, achieving 0.5-1.8 MS2 log10 reduction at flow rates 0.5-2.3 L min-1, corresponding to reduction equivalent doses (RED) up to 16 or 30 mJ/cm2 for 254 and 285 nm, respectively. With hydropowered UV LEDs alone, MS2 log10 reduction decreased to <0.3 log10 reduction due to an underperforming and grossly inefficient turbine, with RED of 8 or 18 mJ/cm2 for 254 and 285 nm, respectively. Assessment of existing markets of UV disinfection systems and pico-hydro turbines demonstrated that hydropowered UV systems are already theoretically feasible for scales at point-of-entry (POE) and above. Economic feasibility will improve if turbines and/or UV system efficiencies improve. Prototype hydropower UV LED systems ranged from $145 to 220 depending on the UV LED reactor, and the battery system added $81. This study demonstrates the practicality of sustainable, renewable energy POU UV disinfection technology that can benefit decentralised, off-grid, rural and remote communities. The system may also scale up to provide renewable energy disinfection at larger scales, such as buildings and water distribution systems, for protecting human health in highly populated areas.
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Affiliation(s)
- Daniel Ma
- Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, Columbus, OH, USA
| | - Clarissa Belloni
- Department of Mechanical Engineering, The Ohio State University, Columbus, OH, USA
| | - Natalie M Hull
- Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, Columbus, OH, USA
- The Sustainability Institute, The Ohio State University, Columbus, OH, USA
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2
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Wang JJ, Zhou YY, Xiang JL, Du HS, Zhang J, Zheng TG, Liu M, Ye MQ, Chen Z, Du Y. Disinfection of wastewater by a complete equipment based on a novel ultraviolet light source of microwave discharge electrodeless lamp: Characteristics of bacteria inactivation, reactivation and full-scale studies. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 917:170200. [PMID: 38296065 DOI: 10.1016/j.scitotenv.2024.170200] [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: 11/10/2023] [Revised: 01/14/2024] [Accepted: 01/14/2024] [Indexed: 02/06/2024]
Abstract
Ultraviolet (UV) light is widely used for wastewater disinfection. Traditional electrode-excited UV lamps, such as low-pressure mercy lamps (LPUV), encounter drawbacks like electrode aging and rapid light attenuation. A novel UV source of microwave discharge electrodeless lamp (MDEL) has aroused attention, yet its disinfection performance is unclear and still far from practical application. Here, we successfully developed a complete piece of equipment based on MDELs and achieved the application for disinfection in wastewater treatment plants (WWTPs). The light emitted by an MDEL (MWUV) shared a spectrum similar to that of LPUV, with the main emission wavelength at 254 nm. The inactivation rate of Gram-negative E. coli by MWUV reached 4.5 log at an intensity of 1.6 mW/cm2 and a dose of 20 mJ/cm2. For Gram-positive B. subtilis, an MWUV dose of 50 mJ/cm2 and a light intensity of 1.2 mW/cm2 reached an inactivation rate of 3.4 log. A higher MWUV intensity led to a better disinfection effect and a lower photoreactivation rate of E. coli. When inactivated by MWUV with an intensity of 1.2 mW/cm2 and a dose of 16 mJ/cm2, the maximum photoreactivation rate and reactivation rate constant Kmax of E. coli were 0.63 % and 0.11 % h-1 respectively. Compared with the photoreactivation, the dark repair of E. coli was insignificant. The full-scale application of the MDEL equipment was conducted in two WWTPs (10,000 m3/d and 15,000 m3/d). Generally 2-3 log inactivation rates of fecal coliforms in secondary effluent were achieved within 5-6 s contact time, and the disinfected effluent met the emission standard (1000 CFU/L). This study successfully applied MDEL for disinfection in WWTPs for the first time and demonstrated that MDEL has broad application prospects.
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Affiliation(s)
- Jun-Jie Wang
- College of Architecture and Environment, Sichuan University, Chengdu 610000, China
| | - Yun-Yi Zhou
- College of Architecture and Environment, Sichuan University, Chengdu 610000, China
| | - Jue-Lin Xiang
- College of Architecture and Environment, Sichuan University, Chengdu 610000, China
| | - Hai-Sheng Du
- Sichuan Macyouwei Environmental Protection Technology Co., Ltd, Chengdu 610000, China
| | - Jin Zhang
- Sichuan Science City Tianren Environmental Protection Co., Ltd, Mianyang 621022, China
| | - Ti-Gang Zheng
- Sichuan Science City Tianren Environmental Protection Co., Ltd, Mianyang 621022, China
| | - Min Liu
- College of Architecture and Environment, Sichuan University, Chengdu 610000, China
| | - Ming-Qi Ye
- Everbright Water (Shenzhen) Limited, Shenzhen 518000, China
| | - Zhuo Chen
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Ye Du
- College of Architecture and Environment, Sichuan University, Chengdu 610000, China.
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3
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Chen X, Chen Z, Ngo HH, Mao Y, Cao K, Shi Q, Lu Y, Hu HY. Comparison of inactivation characteristics between Gram-positive and Gram-negative bacteria in water by synergistic UV and chlorine disinfection. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 333:122007. [PMID: 37302789 DOI: 10.1016/j.envpol.2023.122007] [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: 02/28/2023] [Revised: 04/23/2023] [Accepted: 06/08/2023] [Indexed: 06/13/2023]
Abstract
Disinfection is essential in water and wastewater treatment process as a guarantee for microbial safety. This study systematically investigated: (i) the inactivation characteristics of bacteria widely existed in water, including Gram-negative bacteria (Escherichiacoli) and Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis spores), by sequential UV and chlorine disinfection processes (UV-Cl and Cl-UV), simultaneous UV and chlorine disinfection process (UV/Cl); and (ii) the disinfection mechanisms on different bacteria. The combination of UV and chlorine disinfection could inactive bacteria at lower doses, but showed no synergistic effect on E. coli. Contrarily, disinfection results indicated that UV/Cl performed an obvious synergistic effect on highly disinfectant-resistant bacteria (e.g. S. aureus and B. subtilis spores). Specifically, UV/Cl at the UV dose of 9 mJ/cm2 and chlorine dose of 2 mg-Cl/L could inactivate S. aureus completely. Moreover, the effectiveness of UV/Cl on the removal of indigenous bacteria in actual water conditions was also confirmed. In short, the study provides significant theoretical and practical implications for ensuring microbial safety during water treatment and use.
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Affiliation(s)
- 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
| | - 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.
| | - Huu Hao Ngo
- School of Civil and Environmental Engineering, University of Technology Sydney, Broadway, NSW, 2007, Australia
| | - 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
| | - Kefan 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
| | - 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
| | - 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
| | - 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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4
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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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5
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Lin Y, Xu X, Tian S, Wang J, Cao S, Huang T, Xie W, Ran Z, Wen G. Inactivation of fungal spores by performic acid in water: Comparisons with peracetic acid. JOURNAL OF HAZARDOUS MATERIALS 2023; 458:131929. [PMID: 37418965 DOI: 10.1016/j.jhazmat.2023.131929] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 06/14/2023] [Accepted: 06/22/2023] [Indexed: 07/09/2023]
Abstract
Performic acid (PFA) has received increasing attention in water disinfection due to its high disinfection efficiency and fewer formation of disinfection by-products. However, the inactivation of fungal spores by PFA has not been investigated. In this study, the results showed that the log-linear regression plus tail model adequately described the inactivation kinetic of fungal spores with PFA. The k values of A. niger and A. flavus with PFA were 0.36 min-1 and 0.07 min-1, respectively. Compared to peracetic acid, PFA was more efficient in inactivating fungal spores and caused more serious damage on cell membrane. Compared to neutral and alkaline conditions, acidic environments demonstrated a greater inactivation efficiency for PFA. The increase of PFA dosage and temperature had a promoting effect on the inactivation efficiency of fungal spores. PFA could kill the fungal spores by damaging cell membrane and penetration of cell membranes. In real water, the inactivation efficiency declined as a result of the existence of background substances such as dissolved organic matter. Moreover, the regrowth potential of fungal spores in R2A medium were severely inhibited after inactivation. This study provides some information for PFA to control fungi pollution and explores the mechanism of PFA inactivation.
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Affiliation(s)
- Yuzhao Lin
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Xiangqian Xu
- Wuhan Polytechnic University, Wuhan 430023, PR China
| | - Shiqi Tian
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Jingyi Wang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Shumiao Cao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Tinglin Huang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Weiping Xie
- School of Materials and Environmental Engineering, Shenzhen Polytechnic, Shenzhen 518000, PR China
| | - Zhilin Ran
- School of Transportation and Environment, Shenzhen Institute of Information Technology, Shenzhen 518172, PR China
| | - Gang Wen
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, PR China.
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6
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Sánchez-Montes I, Santos GOS, Dos Santos AJ, Fernandes CHM, Souto RS, Chelme-Ayala P, El-Din MG, Lanza MRV. Toxicological aspect of water treated by chlorine-based advanced oxidation processes: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 878:163047. [PMID: 36958544 DOI: 10.1016/j.scitotenv.2023.163047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 03/16/2023] [Accepted: 03/20/2023] [Indexed: 05/13/2023]
Abstract
As well established in the literature, residual toxicity is an important parameter for evaluating the sanitary and environmental safety of water treatment processes, and this parameter becomes even more crucial when chlorine-based processes are applied for water treatment. Eliminating initial toxicity or preventing its increase after water treatment remains a huge challenge mainly due to the formation of highly toxic disinfection by-products (DBPs) that stem from the degradation of organic contaminants or the interaction of the chlorine-based oxidants with different matrix components. In this review, we present a comprehensive discussion regarding the toxicological aspects of water treated using chlorine-based advanced oxidation processes (AOPs) and the recent findings related to the factors influencing toxicity, and provide directions for future research in the area. The review begins by shedding light on the advances made in the application of free chlorine AOPs and the findings from studies conducted using electrochemical technologies based on free chlorine generation. We then delve into the insights and contributions brought to the fore regarding the application of NH2Cl- and ClO2-based treatment processes. Finally, we broaden our discussion by evaluating the toxicological assays and predictive models employed in the study of residual toxicity and provide an overview of the findings reported to date on this subject matter, while giving useful insights and directions for future research on the topic.
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Affiliation(s)
- Isaac Sánchez-Montes
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos, SP, Brazil; Department of Civil and Environmental Engineering, University of Alberta, T6G 1H9 Edmonton, AB, Canada.
| | - Géssica O S Santos
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos, SP, Brazil
| | - Alexsandro J Dos Santos
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos, SP, Brazil
| | - Carlos H M Fernandes
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos, SP, Brazil
| | - Robson S Souto
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos, SP, Brazil
| | - Pamela Chelme-Ayala
- Department of Civil and Environmental Engineering, University of Alberta, T6G 1H9 Edmonton, AB, Canada
| | - Mohamed Gamal El-Din
- Department of Civil and Environmental Engineering, University of Alberta, T6G 1H9 Edmonton, AB, Canada
| | - Marcos R V Lanza
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos, SP, Brazil.
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7
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Itani N, El Fadel M. Microbial inactivation kinetics of UV LEDs and effect of operating conditions: A methodological critical analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 885:163727. [PMID: 37120022 DOI: 10.1016/j.scitotenv.2023.163727] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 04/20/2023] [Accepted: 04/21/2023] [Indexed: 05/10/2023]
Abstract
Tiny ultraviolet (UV) light-emitting diodes (LED)s that are replacing the conventional energy-intensive mercury UV lamps have gained interest since the early 2000's because of their promising advantages. In the context of microbial inactivation (MI) of waterborne microbes, disinfection kinetics of those LEDs exhibited variations among studies, in terms of varying the UV wavelength, the exposure time, power, and dose (UV fluence) as well as other operational conditions. While reported results may appear contradictory when examined separately, they probably are not when analyzed collectively. As such, in this study, we carry out a quantitative collective regression analysis of the reported data to shed light on the kinetics of MI by the emerging UV LEDs technology alongside the effects of varying operational conditions. The main goal is to identify dose response requirements for UV LEDs and to compare them to traditional UV lamps in addition to ascertaining optimal settings that could help in achieving the optimal inactivation outcome for comparable UV doses. The analysis showed that kinetically, UV LEDs are as effective as conventional mercury lamps for water disinfection, and at times more effective, especially for UV resistant microbes. We defined the maximal efficiency at two wavelengths, 260-265 nm and 280 nm, among a wide range of available LED wavelengths. We also defined the UV fluence per log inactivation of tested microbes. At the operational level, we identified existing gaps and developed a framework for a comprehensive analysis program for future needs.
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Affiliation(s)
- N Itani
- Department of Civil Infrastructure and Environmental Engineering, Khalifa University, United Arab Emirates; Department of Civil and Environmental Engineering, American University of Beirut, Lebanon
| | - M El Fadel
- Department of Civil Infrastructure and Environmental Engineering, Khalifa University, United Arab Emirates; Department of Civil and Environmental Engineering, American University of Beirut, Lebanon.
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8
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Zhang YL, Lin YL, Zhang TY, Lu YS, Zhou XY, Liu Z, Zheng ZX, Xu MY, Xu B. Degradation of odorous 2,4,6-trichloroanisole in chlorinated water by UV-LED/chlorination: kinetics and influence factors. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:44325-44336. [PMID: 36690857 DOI: 10.1007/s11356-023-25337-6] [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] [Accepted: 01/11/2023] [Indexed: 06/17/2023]
Abstract
2,4,6-Trichloroanisole (2,4,6-TCA) has aroused a special concern for their odor problem and potential threats. In this study, the degradation of 2,4,6-TCA by UV/chlorination with different UV sources was compared, including low-pressure mercury lamp (LPUV, 254 nm) and ultraviolet light-emitting diode (UV-LED, 275 and 285 nm). The maximum removal of 2,4,6-TCA can be achieved by 275-nm UV-LED/chlorination in neutral and alkaline conditions which was 80.0%. The reaction, kinetics, and water matrix parameters on 2,4,6-TCA degradation were also evaluated. During UV-LED (275 nm)/chlorination, 2,4,6-TCA degradation was mainly caused by direct UV photolysis and indirect hydroxyl radical (HO·) oxidation, while reactive chlorine radicals (RCSs) had a negligible contribution. The second-order rate constant between HO· and 2,4,6-TCA was determined as 3.1 × 109 M-1 s-1. Increasing initial chlorine dosage and decreasing 2,4,6-TCA concentration or pH value significantly promoted 2,4,6-TCA degradation during UV/chlorination process. The presence of natural organic matter (NOM) and bicarbonate (HCO3-) can inhibit 2,4,6-TCA degradation, while chloride ion (Cl-) had a negligible effect. The kinetic model for 2,4,6-TCA degradation was established and validated, and the degradation pathways were proposed based on the identified intermediates. Furthermore, UV-LED (275 nm)/chlorination also exhibited a promising effect on 2,4,6-TCA removal in real water, which can be used to control 2,4,6-TCA pollution and odor problems.
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Affiliation(s)
- Yun-Lu Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, People's Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, People's Republic of China
| | - Yi-Li Lin
- Department of Safety, Health and Environmental Engineering, National Kaohsiung University of Science and Technology, 824, Kaohsiung, Taiwan, Republic of China
| | - Tian-Yang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, People's Republic of China.
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, People's Republic of China.
| | - Yong-Shan Lu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, People's Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, People's Republic of China
| | - Xiao-Yang Zhou
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, People's Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, People's Republic of China
| | - Zhi Liu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, People's Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, People's Republic of China
| | - Zheng-Xiong Zheng
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, People's Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, People's Republic of China
| | - Meng-Yuan Xu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, People's Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, People's Republic of China
| | - Bin Xu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, People's Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, People's Republic of China
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9
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Gandhi J, Prakash H. Photo-disinfection Processes for Bacterial Inactivation and Underlying Principles for Water Constituents’ Impact: A Review. CHEMICAL ENGINEERING JOURNAL ADVANCES 2023. [DOI: 10.1016/j.ceja.2023.100482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023] Open
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10
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Balakrishnan A, Jacob MM, Senthil Kumar P, Kapoor A, Ponnuchamy M, Sivaraman P, Sillanpää M. Strategies for safe management of hospital wastewater during the COVID-19 pandemic. INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY : IJEST 2023; 20:1-16. [PMID: 36817164 PMCID: PMC9925218 DOI: 10.1007/s13762-023-04803-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 09/18/2022] [Accepted: 01/27/2023] [Indexed: 06/18/2023]
Abstract
Management of hospital wastewater is a challenging task, particularly during the situations like coronavirus 2019 (COVID-19) pandemic. The hospital effluent streams are likely to contain many known and unknown contaminants including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) along with a variety of pollutants arising from pharmaceuticals, life-style chemicals, drugs, radioactive species, and human excreta from the patients. The effluents are a mixed bag of contaminants with some of them capable of infecting through contact. Hence, it is essential to identify appropriate treatment strategies for hospital waste streams. In this work, various pollutants emerging in the context of COVID-19 are examined. A methodical review is conducted on the occurrence and disinfection methods of SARS-CoV-2 in wastewater. An emphasis is given to the necessity of addressing the challenges of handling hospital effluents dynamically involved during the pandemic scenario to ensure human and environmental safety. A comparative evaluation of disinfection strategies makes it evident that the non-contact methods like ultraviolet irradiation, hydrogen peroxide vapor, and preventive approaches such as the usage of antimicrobial surface coating offer promise in reducing the chance of disease transmission. These methods are also highly efficient in comparison with other strategies. Chemical disinfection strategies such as chlorination may lead to further disinfection byproducts, complicating the treatment processes. An overall analysis of various disinfection methods is presented here, including developing methods such as membrane technologies, highlighting the merits and demerits of each of these processes. Finally, the wastewater surveillance adopted during the COVID-19 outbreak is discussed. Supplementary Information The online version contains supplementary material available at 10.1007/s13762-023-04803-1.
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Affiliation(s)
- A. Balakrishnan
- Department of Chemical Engineering, National Institute of Technology Rourkela, Rourkela, Odisha 769008 India
| | - M. M. Jacob
- Department of Chemical Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203 India
| | - P. Senthil Kumar
- Department of Chemical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Kalavakkam, Chennai 603203 India
- Centre of Excellence in Water Research (CEWAR), Sri Sivasubramaniya Nadar College of Engineering, Kalavakkam, Chennai 603203 India
- School of Engineering, Lebanese American University, Byblos, Lebanon
- Department of Biotechnology Engineering and Food Technology, Chandigarh University, Mohali, 140413 India
| | - A. Kapoor
- Department of Chemical Engineering, Harcourt Butler Technical University, Kanpur, Uttar Pradesh 208002 India
| | - M. Ponnuchamy
- Department of Chemical Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203 India
| | - P. Sivaraman
- Department of Chemical Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu 603203 India
| | - M. Sillanpää
- Department of Chemistry, College of Science, King Saud University, Riyadh, 11451 Saudi Arabia
- School of Resources and Environment, University of Electronic Science and Technology of China (UESTC), NO. 2006, Xiyuan Ave., West High-Tech Zone, Chengdu, Sichuan 611731 People’s Republic of China
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11
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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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12
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Yuan X, Li Y, Mo Q, Zhang B, Shu D, Sun L, Zhao X, Zhang R, Zheng J, Jia Y, Zang Y. Antibacterial activity and mechanism of slightly acidic electrolyzed water combined with ultraviolet light against Salmonella enteritidis. Food Control 2023. [DOI: 10.1016/j.foodcont.2023.109681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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13
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Lu YH, Wu H, Zhang HH, Li WS, Lai ACK. Synergistic disinfection of aerosolized bacteria and bacteriophage by far-UVC (222-nm) and negative air ions. JOURNAL OF HAZARDOUS MATERIALS 2023; 441:129876. [PMID: 36087531 DOI: 10.1016/j.jhazmat.2022.129876] [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: 06/23/2022] [Revised: 08/22/2022] [Accepted: 08/28/2022] [Indexed: 06/15/2023]
Abstract
Air ionizers and 222-nm krypton-chlorine (KrCl) excilamp have proven to be effective disinfection apparatus for bacteria and viruses with limited health risks. We determined inactivation efficiencies by operating them individually and in combined modules. Gram-positive and gram-negative bacteria, non-enveloped dsDNA virus, and enveloped dsRNA virus were examined in a designed air disinfection system. Our results showed that the bioaerosols were inactivated efficiently by negative ionizers and far-UVC (222-nm), either used individually or in combination. Among which the combined modules of negative ionizers and KrCl excilamp had the best disinfection performance for the bacteria. The aerosolized virus P22 and Phi 6 were more susceptible to 222-nm emitted by KrCl excilamp than negative air ions. Significant greater inactivation of bacterial bioaerosols were identified after treated by combined treatment of negative air ion and far-UVC for 2 minutes (Escherichia coli, 6.25 natural log (ln) reduction; Staphylococcus epidermidis, 3.66 ln reduction), as compared to the mean sum value of inactivation results by respective individual treatment of negative ionizers and KrCl excilamp (Escherichia coli, 4.34 ln; Staphylococcus epidermidis, 1.75 ln), indicating a synergistic inactivation effect. The findings provide important baseline data to support the design and development of safe and high-efficient disinfection systems.
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Affiliation(s)
- Y H Lu
- Department of Architecture and Civil Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong China
| | - H Wu
- Department of Architecture and Civil Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong China; Department of Biology, Hong Kong Baptist University, Kowloon, Hong Kong China
| | - H H Zhang
- Department of Architecture and Civil Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong China
| | - W S Li
- School of Public Health, The University of Hong Kong, Pokfulam, Hong Kong China
| | - A C K Lai
- Department of Architecture and Civil Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong China.
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14
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Gholizade A, Asadollahfardi G, Rezaei R. Reactive Blue 19 dye removal by UV-LED/chlorine advanced oxidation process. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:1704-1718. [PMID: 35922593 DOI: 10.1007/s11356-022-22273-9] [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: 03/03/2022] [Accepted: 07/24/2022] [Indexed: 06/15/2023]
Abstract
In recent years, advanced oxidation processes (AOPs) have indicated the greatest potential in the removal of stable organic compounds, including dyes. In this study, the ultraviolet light-emitting diodes (UV-LEDs) combined with chlorine was evaluated to remove Reactive Blue 19 (RB19) dye from aqueous solution. The effect of key experimental parameters including pH, initial chlorine concentration, initial dye concentration, and reaction time on the performance of UV-LED irradiation, UV-LED/chlorine, and the chlorination method for the removal of RB19 was studied in this research. Results showed that, more than 99% of RB19 was removed after 30 min of reaction time under optimized conditions (pH = 5, [chlorine] = 300 μM, and [RB19] = 20 mg L-1) with apparent kinetic rate constant (kapp) of 17.1 × 10-2 min-1 in UV-LED/chlorine process. However, for the chlorination method, removal efficiency was 64.7% (kapp = 3.41 × 10-2 min-1) with an apparent kinetic rate constant of 0.0341 min-1. Results also showed that UV-LED irradiation is not effective at all in removing RB19. The scavenging assay showed that OH• radicals (67.23%) had the highest contribution in RB19 removal in UV-LED/chlorine process while Cl• (17.82%) and [Formula: see text] (8.56%) had a minor role in the degradation of the dye. The RB19 degradation kinetics analysis revealed that the processes of UV-LED/chlorine and chlorination degradation followed the pseudo-first-order kinetic model. In this study, the impact of chloride, nitrate, bicarbonate, carbonate, sulfate, and sulfite anions on the performance of the process was investigated. It indicated that sulfite anion has the most negative impact on the RB19 removal process. By evaluating the synergistic effect between UV-LED lamp and chlorine, a synergy index of 5.0 was obtained for the UV-LED/chlorine process. The results presented that the UV-LED/chlorine process has a better performance than each of them alone and has the necessary efficiency for RB19 removal. Measuring COD reported its removal efficiency of 98% during the UV-LED/chlorine process under optimized conditions. Experiments continued with textile factory wastewater and indicated 30.9% of its COD removed after treatment when 1.0 μM chlorine was used.
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Affiliation(s)
- Alireza Gholizade
- MSc of Environmental Engineering, Kharazmi University, 43 Shahid Mofatteh Ave, Tehran, Iran
| | - Gholamreza Asadollahfardi
- Emeritus professor, Civil Engineering Department, Faculty of Engineering, Kharazmi University, Tehran, Iran.
| | - Reza Rezaei
- Aqua Intelligent Technology, 2366 Main Mall, Vancouver, BC, V6T 1Z4, Canada
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15
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Xiao D, Wang N, Chen S, Wang S, Yuan X, Fan W, Huo M. Synergism in sequential inactivation of Cryptosporidium parvum with trypsin and UV irradiation. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:8354-8362. [PMID: 36445526 DOI: 10.1007/s11356-022-24408-4] [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: 07/11/2022] [Accepted: 11/22/2022] [Indexed: 06/16/2023]
Abstract
Cryptosporidium, a protozoan parasite, in wastewater presents a major public health concern for water safety. However, bactericidal efficiencies of conventional disinfection methods towards Cryptosporidium oocysts are still hampered owing to the presence of their thick outer wall. In this study, we present a novel UV inactivation process where the efficiency has been significantly enhanced by addition of a trypsin pretreatment stage. Notably, inactivation (log-reduction) of oocysts was noted to be 73.75-294.72% higher than that obtained by UV irradiation alone, under identical conditions. Experimental observations and supporting mechanistic analyses suggest that trypsin led to cleavage of the protein layers on the oocyst wall, facilitating penetration of UV radiation into the oocysts leading to degradation of their genomic DNA (gDNA). The dissociative effect of trypsin on the oocyst wall was indicated by the fact that 64.50% of oocysts displayed early apoptosis after trypsinization. Imaging by scanning electron microscopy indicated that this combined treatment led to substantial disruption of the oocyst coat, deforming their shape. This resulted in the release of cellular proteins and gDNA, their concentrations in bulk solution increasing by 1.22-8.60 times. As UV irradiation time was prolonged, gDNA was degraded into smaller fragments with lower molecular masses. Both laddering and diffuse smear patterns in gel analysis indicated significantly detrimental effects on gDNA and viability of oocysts. Overall, this study demonstrated enhancement of UV inactivation of Cryptosporidium oocysts by trypsin and explored the underlying mechanisms for the process.
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Affiliation(s)
- Dan Xiao
- Jilin Academy of Agricultural Sciences, Changchun, 130033, China
| | - Nan Wang
- Jilin Academy of Animal Husbandry and Veterinary Medicine, Changchun, 130062, China
| | - Shiheng Chen
- School of Chemical Engineering, Changchun University of Technology, Changchun, 130012, China
| | - Siyue Wang
- Jilin Academy of Agricultural Sciences, Changchun, 130033, China
| | - Xiangyi Yuan
- School of Environment, Northeast Normal University, Changchun, 130117, China
| | - Wei Fan
- School of Environment, Northeast Normal University, Changchun, 130117, China.
| | - Mingxin Huo
- School of Environment, Northeast Normal University, Changchun, 130117, China
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16
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B. Soro A, Shokri S, Nicolau-Lapeña I, Ekhlas D, Burgess CM, Whyte P, Bolton DJ, Bourke P, Tiwari BK. Current challenges in the application of the UV-LED technology for food decontamination. Trends Food Sci Technol 2022. [DOI: 10.1016/j.tifs.2022.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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17
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Chen Y, Jafari I, Zhong Y, Chee MJ, Hu J. Degradation of organics and formation of DBPs in the combined LED-UV and chlorine processes: Effects of water matrix and fluorescence analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 846:157454. [PMID: 35868393 DOI: 10.1016/j.scitotenv.2022.157454] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/12/2022] [Accepted: 07/13/2022] [Indexed: 06/15/2023]
Abstract
Combined processes of light-emitting diodes ultraviolet (LED UV) and chlorination (Cl2) are alternative disinfection technologies in drinking water, while the formation of disinfection by-products (DBPs) needs to be evaluated. This study investigated the impacts of critical water matrix factors on the DBP formation in the combined processes. Moreover, the correlation between the degraded natural organic matter (NOM) and the formed DBP was studied. Simultaneous UV/Cl2 outperformed single Cl2 and sequential combined processes in degrading humic acids (HA) and resulted in the highest DBP yield. Iodide at 5-20 μg/L and bromide at 0.05-0.2 mg/L slightly affected the degradation of organics, while increased the formation of brominated DBPs up to 36.6 μg/L. pH 6 was regarded as the optimum pH, achieving high efficiency of HA degradation and a lower level of total DBP formation than pH 7 and 8 by 11 % and 24 %, respectively. Compared to HA samples (46.8-103.9 μg/L per mg/L DOC), NOM in canal water were less aromatic and yielded fewer DBPs (19.6 and 21.2 μg/L per mg/L DOC). However, the extremely high bromide in site 1 samples (18.6 mg/L) shifted the chlorinated DBPs to their brominated analogues, posting around 1 order of magnitude higher levels of toxicities than HA samples. The reduction of absorbance at 254 nm (UV254) correlated with all DBP categories in HA samples, while the correlation coefficients were compromised when included in the canal samples. For the first time, this study found that parallel factor analysis (PARAFAC) would neglect the fluorescence change caused by iodide/bromide in UV/Cl2, while the changes could be captured by self-organising map (SOM) trained with full fluorescence spectra. Fluorescence Ex/Em pairs were proposed to predict DBP formation, suggesting a potential method to develop an online monitoring system for DBPs.
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Affiliation(s)
- Yiwei Chen
- NUS Environmental Research Institute, National University of Singapore, 5A Engineering Drive 1, Singapore 117411, Singapore
| | - Iman Jafari
- Department of Civil & Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576, Singapore
| | - Yu Zhong
- Department of Civil & Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576, Singapore
| | - Min Jun Chee
- Department of Civil & Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576, Singapore
| | - Jiangyong Hu
- NUS Environmental Research Institute, National University of Singapore, 5A Engineering Drive 1, Singapore 117411, Singapore; Department of Civil & Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576, Singapore.
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18
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Chen X, Chen Z, Liu H, Huang N, Mao Y, Cao K, Shi Q, Lu Y, Hu HY. Synergistic effects of UV and chlorine in bacterial inactivation for sustainable water reclamation and reuse. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 845:157320. [PMID: 35839898 DOI: 10.1016/j.scitotenv.2022.157320] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 06/30/2022] [Accepted: 07/08/2022] [Indexed: 06/15/2023]
Abstract
Disinfection is a necessity in water and wastewater treatment and reclamation. This study examined the inactivation of a disinfectant resistant but widely existed opportunistic pathogen in reclaimed water, Staphylococcus aureus (S. aureus), by sequential UV and chlorine disinfection or simultaneous UV and chlorine disinfection (UV/Cl). It was identified that UV/Cl greatly promoted the inactivation efficacy and inhibited photoreactivation of S. aureus by the generation of free radicals (i.e. OH and Cl), which reached a 7-log10 reduction at UV and chlorine doses of 18 mJ/cm2 and 2 mg-Cl/L, respectively. The changes of bacterial viability and morphology and the increase of extracellular ATP concentration confirmed the enhancement of cell membranes damages (>21.4 %) due to free radicals generated in UV/Cl process, which caused a dramatic reduction in metabolic activity and suppressed the photoreactivation. Furthermore, this study demonstrated that UV/Cl effectively removed heterotrophic plate count bacteria and aromatic organic fluorophores in reclaimed water samples. This study is of significant theoretical and applicable importance in guaranteeing safe microbial levels for water reclamation and reuse.
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Affiliation(s)
- 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
| | - 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.
| | - 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
| | - Nan 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, 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
| | - Kefan 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
| | - 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
| | - 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
| | - 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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19
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Liu P, Wu X, Pan S, Dai J, Zhang Z, Guo X. Photochlorination-induced degradation of microplastics and interaction with Cr(VI) and amlodipine. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 835:155499. [PMID: 35472361 DOI: 10.1016/j.scitotenv.2022.155499] [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: 02/25/2022] [Revised: 04/16/2022] [Accepted: 04/20/2022] [Indexed: 06/14/2023]
Abstract
Wastewater treatment plants (WWTPs) are the important source of microplastics (MPs) in the environment, and disinfection processes bear high potential to degrade MPs. This study investigated the physicochemical degradation, dissolved organic products and interaction with co-existed pollutants (heavy metal and pharmaceutical) on polyethylene (PE), polypropylene (PP) and polystyrene (PS) MPs during simulated disinfection processes. Compared to photo or chlorination, photochlorination significantly resulted in the physicochemical degradation, including morphology alteration, fragmentation, and chemical oxidation on PP and PS MPs, but showed relatively low effect on PE, indicating the different resistance among polymers to disinfected treatment. Photochlorination also caused the formation of chain-scission organic compounds and even chlorinated products from MPs (e.g. C11H19O4Cl for PP and monochlorophenol, dichlorophenol, chloroacetophenone and chlorobenzoic acid for PS), which may form disinfection byproducts to induce healthy risk. The adsorption potentials of MPs for Cr(VI) or amlodipine were enhanced by photochlorination since the cracking and formed oxygen functional groups enhanced the pore filling and surface precipitation of Cr(VI), and the electrostatic attraction and hydrogen bonding with amlodipine. The findings indicated the physicochemical degradation of MPs and the combined pollution with co-existed pollutants, highlighting the health risks of MP-derived organic products during the disinfection treatments (even in normal dosage) in WWTPs.
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Affiliation(s)
- Peng Liu
- College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China; Key Laboratory of Plant Nutrition and the Agro-environment in Northwest China, Ministry of Agriculture, Yangling 712100, China
| | - Xiaowei Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Suyi Pan
- College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China
| | - Jiamin Dai
- College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China
| | - Zixuan Zhang
- College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China
| | - Xuetao Guo
- College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China; Key Laboratory of Plant Nutrition and the Agro-environment in Northwest China, Ministry of Agriculture, Yangling 712100, China.
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20
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Study on the Disinfection Efficiency of the Combined Process of Ultraviolet and Sodium Hypochlorite on the Secondary Effluent of the Sewage Treatment Plant. Processes (Basel) 2022. [DOI: 10.3390/pr10081622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The combined disinfection process of ultraviolet and sodium hypochlorite has more advantages than the single disinfection method in reducing the disinfectant dosage, shortening the reaction time, and resisting the impact of water quality changes and inhibiting the light reactivation of microorganisms. Given this, using the secondary effluent of a sewage plant as the research object, the disinfection efficiency of the combined process of ultraviolet and sodium hypochlorite was investigated. The experimental results showed that the inactivation effect of UV followed by sodium hypochlorite on fecal coliform and the inhibition of microbial photoreactivation was more significant than that of simultaneous disinfection of UV and sodium hypochlorite disinfection. When the UV dose was 24 mJ/cm2, after disinfection with UV followed by sodium hypochlorite, only 1 mg/L of sodium hypochlorite was required to be added, and a contact reaction time of 1 min for the fecal coliform index to meet the first-Class A emission standard. After disinfection, the effluent’s maximum reactivation rate of fecal coliform was 26.96%. However, the simultaneous disinfection of ultraviolet and sodium hypochlorite required the addition of 3 mg/L of sodium hypochlorite. After disinfection, the maximum reactivation rate of the fecal coliform group reached 30.81%.
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21
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Wan Q, Xia Y, Li Y, Wu G, Wang J, Huang T, Wen G. Enhanced solar inactivation of fungal spores by addition of low-dose chlorine: Efficiency and mechanism. WATER RESEARCH 2022; 222:118964. [PMID: 35970005 DOI: 10.1016/j.watres.2022.118964] [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: 05/14/2022] [Revised: 08/05/2022] [Accepted: 08/07/2022] [Indexed: 06/15/2023]
Abstract
This work demonstrated that the solar inactivation of fungal spores was enhanced by addition of low-dose chlorine. Although the effect of low-dose chlorine alone (2.0 mg/L) on culturability of fungal spores was negligible, the solar/chlorine inactivation on fungal spores performed better than solar alone inactivation, with a lower shoulder length and a higher maximum inactivation rate constant. The enhanced inactivation of Aspergillus niger can be ascribed to the membrane oxidation by chlorine, and the enhanced inactivation of Penicillium polonicum can be ascribed to the membrane oxidation by chlorine and ·OH (·OH plays a major role). The oxidization by chlorine and ·OH led to an increase in membrane permeability of fungal spores, which enhanced the solar inactivation, resulting in an increase in intracellular ROS and more serious morphological damage. Due to the presence of background substances such as dissolved organic matter and metal ions (Fe2+, Mn2+, etc.), the inactivation efficiency in real water matrices was decreased. The main disinfection by-products (DBPs) produced in the inactivation of fungal spores in chlorine alone and solar/chlorine treatments were dichloroacetic acid, trichloroacetic acid, trichloroacetone and trichloromethane. Generally, DBPs formation in solar/chlorine treatment was lower than those in chlorine alone treatment. Moreover, the regrowth potential of the two genera of fungal spores in R2A medium could be inhibited by adding low-dose chlorine.
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Affiliation(s)
- Qiqi Wan
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Yuancheng Xia
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Yangfan Li
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Gehui Wu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Jingyi Wang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Tinglin Huang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Gang Wen
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, PR China.
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22
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Cai G, Liu T, Zhang J, Song H, Jiang Q, Zhou C. Control for chlorine resistant spore forming bacteria by the coupling of pre-oxidation and coagulation sedimentation, and UV-AOPs enhanced inactivation in drinking water treatment. WATER RESEARCH 2022; 219:118540. [PMID: 35550966 DOI: 10.1016/j.watres.2022.118540] [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: 02/04/2022] [Revised: 04/06/2022] [Accepted: 05/02/2022] [Indexed: 06/15/2023]
Abstract
Spore forming bacteria (SFB) are strongly chlorine resistant. Their presence in drinking water may cause diseases and pose threat to public health. Three SFB strains, i.e. Bacillus alvei, Bacillus cereus, and Lysinibacillus fusiformis, were isolated and identified from the finished water of a drinking water treatment plant where bacteria colonies occasionally reached the limit value. Due to their chlorine resistance, a SFB control strategy coupling pre-oxidation, coagulation sedimentation, and UV-AOPs inactivation in water treatment process was studied in lab scale. Five minutes pre-oxidation treatment by applying Cl2 and ClO2 induced remarkable spore transformation. Longer pre-oxidation exposure time didn't have apparent improvement. Cl2 and ClO2 dosages of 0.9 mg/L and 0.5 mg/L were suggested, respectively. The formed spores can be efficiently removed by the following coagulation sedimentation treatment. At a suggested dosage combination of 20 mg/L PAC and 0.08 mg/L PAM, spore removal efficiency reached about 3.15-lg. Comparing to applying sole UV irradiation, enhanced UV inactivation by adding 0.1 mM H2O2, or Cl2, or peroxymonosulfate (PMS) substantially improved the inactivation of the most chlorine resistant SFB strain, Lysinibacillus fusiformis. UV-AOPs stably achieved 2-lg inactivation rate at UV dosage of 40 mJ/cm2. UV/H2O2, UV/Cl2 and UV/PMS inactivation kinetically enhanced 1.20 times, 1.36 times and 1.91 times over sole UV irradiation. Intracellular DNA and ATP leakages were detected, and remarkable damages of Lysinibacillus fusiformis cells' surface and ultrastructure were observed. These findings evidenced cell wall and cell membrane destructions, guaranteeing substantial SFB cells inactivation. This study was carried out based on three SFB strains isolated from a finished water, and common engineering practical operations. By providing engineeringly relevant references, the outcomes obtained would be helpful for dealing with SFB outbreak risk in drinking water treatment.
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Affiliation(s)
- Guangqiang Cai
- Harbin Institute of Technology, Shenzhen, Shenzhen, 518055, China; Shenzhen Water Affairs (Group) Co., Ltd., Shenzhen, 518031, China
| | - Tongzhou Liu
- Harbin Institute of Technology, Shenzhen, Shenzhen, 518055, China.
| | - Jinsong Zhang
- Harbin Institute of Technology, Shenzhen, Shenzhen, 518055, China; Shenzhen Water Affairs (Group) Co., Ltd., Shenzhen, 518031, China
| | - Haoran Song
- Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan, 523808, China
| | - Qijun Jiang
- Shenzhen Shen Shui Bao An Water Affairs (Group) Co., Ltd., Shenzhen, 518133, China
| | - Chang Zhou
- School of Civil Engineering, Guangzhou University, Guangzhou, 510006, China
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23
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Wu G, Zhao H, Wan Q, Xu X, Cao R, Li K, Wang J, Huang T, Lu J, Wen G. Inactivation and subsequent reactivation of Aspergillus species by the combination of UV and monochloramine: Comparisons with UV/chlorine. J Environ Sci (China) 2022; 117:105-118. [PMID: 35725063 DOI: 10.1016/j.jes.2022.03.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 02/20/2022] [Accepted: 03/09/2022] [Indexed: 11/18/2022]
Abstract
Ultraviolet (UV)/monochloramine (NH2Cl) as an advanced oxidation process was firstly applied for Aspergillus spores inactivation. This study aims to: i) clarify the inactivation and photoreactivation characteristics of UV/NH2Cl process, ii) compared with UV/Cl2 in inactivation efficiency, photoreactivation and energy consumption. The results illustrated that UV/NH2Cl showed better inactivation efficiency than that of UV alone and UV/Cl2, and could effectively control the photoreactivation. For instance, the inactivation rates for Aspergillus flavus, Aspergillus niger and Aspergillus fumigatus in the processes of UV/NH2Cl (2.0 mg/L) was 0.034, 0.030 and 0.061 cm2/mJ, respectively, which were higher than that of UV alone (0.027, 0.026 and 0.024 cm2/mJ) and UV/Cl2 (0.023, 0.026 and 0.031 cm2/mJ). However, there was no synergistic effect for Aspergillus flavus and Aspergillus fumigatus. As for Aspergillus niger, the best synergistic effect can reach 1.86-log10. This may be due to their different resistance to disinfectants, which were related to the size, an outer layer of rodlets (hydrophobins) and pigments. After UV/NH2Cl inactivation, the degree of cell membrane damage and intracellular reactive oxygen species were higher than that of UV alone. UV/NH2Cl had the advantages of high inactivation efficiency and inhibition of photoreactivation, which provides a new entry point for the disinfection of waterborne fungi.
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Affiliation(s)
- Gehui Wu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; State Key Laboratory of Green Building in Western China, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Hui Zhao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Qiqi Wan
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Xiangqian Xu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Ruihua Cao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Kai Li
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Jingyi Wang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Tinglin Huang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Jinsuo Lu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; State Key Laboratory of Green Building in Western China, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Gang Wen
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; State Key Laboratory of Green Building in Western China, Xi'an University of Architecture and Technology, Xi'an 710055, China.
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24
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Xu X, Zuo J, Wan Q, Cao R, Xu H, Li K, Huang T, Wen G, Ma J. Effective inactivation of fungal spores by the combined UV/PAA: Synergistic effect and mechanisms. JOURNAL OF HAZARDOUS MATERIALS 2022; 430:128515. [PMID: 35739689 DOI: 10.1016/j.jhazmat.2022.128515] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 02/15/2022] [Accepted: 02/17/2022] [Indexed: 06/15/2023]
Abstract
Peracetic acid (PAA) can effectively inactivate fungi in water, while may pose a potential risk of regrowth after disinfection. The inactivation kinetic and mechanism of fungal spores by combined UV and PAA (UV/PAA) was investigated in this study. The results showed that synergistic factor of the inactivation of A. niger and A. flavus was 1.44 and 1.37, which indicated significant synergistic effect of UV/PAA. The k of A. niger and A. flavus was similar at pH 5.0 and 7.0, while decreased 60.00% and 39.13% at pH 9.0 compared with that at pH 7.0. The effect of HA concentration on the inactivation efficiency of fungal spores by UV/PAA was negative, while the effect of PAA concentration was positive. The membrane permeabilized cell of A. niger and A. flavus caused by UV/PAA was 17.0% and 31.7%, which was higher than that caused by PAA and UV alone. The changes of morphology of fungal spores and the leakage of intracellular material indicated that the damage of cell structure caused by UV/PAA system was more serious than that of UV or PAA alone. In addition, the four parts that contributed in UV/PAA system was in the following order: UV > radical > PAA > synergistic effect. The inactivation efficiency of combined UV and chlorine (UV/Cl2) was higher than that of UV/PAA. Furthermore, the typical order of the inactivation efficiency in different matrix was: phosphate buffer solution > surface water > secondary effluent. The regrowth potential of fungal spores after UV/PAA treatment was significantly lower than that by PAA alone, indicating that UV/PAA could decrease the microbial regrowth potential after PAA disinfection alone.
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Affiliation(s)
- Xiangqian Xu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Jie Zuo
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Qiqi Wan
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Ruihua Cao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Huining Xu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Kai Li
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Tinglin Huang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Gang Wen
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Jun Ma
- School of Environment, Harbin Institute of Technology, China
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25
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Song H, Dang YM, Ha S, Ha JH. Evaluation of Virucidal Efficacy of Human Norovirus Using Combined Sprayed Slightly Acidic Electrolyzed Water and Ultraviolet C-Light-Emitting Diode Irradiation Treatment Based on Optimized Capture Assay for Quantitative RT-qPCR. Front Microbiol 2022; 13:841108. [PMID: 35547136 PMCID: PMC9082547 DOI: 10.3389/fmicb.2022.841108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 02/07/2022] [Indexed: 11/26/2022] Open
Abstract
Slightly acidic electrolyzed water (SAEW), an effective non-thermal virucidal treatment, is used widely to prevent infectious viral cross-contamination. Surface disinfection technologies using ultraviolet C-light-emitting diode (UVC-LED) irradiation have recently attracted considerable attention. The SAEW sprayer technique is an efficient approach to preventing the spread of infectious viral pathogens in the public healthcare sector. Therefore, we investigated a small-scale system comprising sprayed SAEW disinfection combined with UVC-LED irradiation to inactivate the human norovirus (HuNoV) in the environment. A stainless-steel surface was inoculated with a HuNoV genogroup II genotype 4 (GII.4) to achieve maximum reduction values of 3.21 log10 genomic copies. For optimal disinfection conditions, the response surface methodology based on the Box–Behnken design revealed that the specific treatment conditions for inactivation of HuNoV GII.4 were an SAEW droplet volume of 180 μL, 30 ppm available chlorine concentration of SAEW, and a UVC-LED exposure dose of 2 mJ/cm2. The results indicate that the combined disinfection treatment could efficiently prevent the spread of HuNoVs in environment. Furthermore, the quadratic polynomial equations of the 3-D response surface can be employed to predict the effects of combined disinfection treatment on HuNoV contamination on environmental surfaces. Therefore, sprayed SAEW disinfection combined with UVC-LED irradiation proposed in this study may offer insights for designing optimal control strategies and techniques to prevent the transmission of infectious diseases, particularly HuNoV.
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Affiliation(s)
- Hyeyeon Song
- Hygienic Safety and Distribution Research Group, World Institute of Kimchi, Gwangju, South Korea
| | - Yun-Mi Dang
- Hygienic Safety and Distribution Research Group, World Institute of Kimchi, Gwangju, South Korea
| | - Sanghyun Ha
- Hygienic Safety and Distribution Research Group, World Institute of Kimchi, Gwangju, South Korea
| | - Ji-Hyoung Ha
- Hygienic Safety and Distribution Research Group, World Institute of Kimchi, Gwangju, South Korea
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26
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Photocatalytic Inactivation of Bacillus subtilis Spores by Natural Sphalerite with Persulfate under Visible Light Irradiation. COATINGS 2022. [DOI: 10.3390/coatings12040528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Bacterial spores are highly resistant to be inactivated by conventional water disinfection methods. In this study, the inactivation efficiency and mechanisms of Bacillus subtitles (B. subtilis) spores by natural sphalerite (NS) with persulfate (PS) under visible light (Vis) irradiation were investigated for the first time. The NS was composed of ZnS doped with trace amounts of metal ions, including As, Fe, Cd, and Mn. The results showed that 7 log of B. subtilis spores could be completely inactivated within 5 h in the Vis/NS/PS photocatalytic system, and the inactivation efficiency was about four and seven times higher than that of the NS/PS system and the Vis/PS system, respectively. The photo-generated electrons are generated by the excitation of NS under the illumination activated PS to form PS radicals (∙SO4−) and hydroxyl radicals (∙OH), which are the main active species for spore inactivation. Mechanism studies further showed that spore inactivation was related to physiological responses, including the increase in intracellular reactive oxygen species, the change of induced antioxidant enzyme activity, and the change of total protein. Furthermore, the dynamic changes of cells during spore inactivation were observed by SEM. These results not only clarify the relationship between the cell physiological stress response and inactivation mechanism of spores, but also reveal the interaction between minerals and PS under Vis, which provides technical methods for the inactivation of bacterial spores in the field of water disinfection.
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27
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Wang J, Bu L, Wu Y, Sun J, Li G, Zhou S. Disinfection profiles and mechanisms of E. coli, S. aureus, and B. subtilis in UV365/chlorine process: Inactivation, reactivation, and DBP formation. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.120584] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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28
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Wei FQ, Lu Y, Shi Q, Chen Z, Li KX, Zhang T, Shi YL, Xu Q, Hu HY. A dose optimization method of disinfection units and synergistic effects of combined disinfection in pilot tests. WATER RESEARCH 2022; 211:118037. [PMID: 35026550 DOI: 10.1016/j.watres.2022.118037] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 12/27/2021] [Accepted: 01/02/2022] [Indexed: 06/14/2023]
Abstract
The increasing requirement for reclaimed water has made it necessary to utilize multiple disinfection processes for efficient removal of organoleptic indicators, while guaranteeing microbial safety. However, there is not a proper way to appropriately distribute the operation load between different disinfection units. This study provides a new method to optimize doses of sequential ozonation, ultraviolet (UV) irradiation and chlorine disinfection units, and investigates the synergistic effects of combined disinfection on the basis of pilot tests. In this method, the minimal ozone dose is determined first for the removal of colority. The chlorine dose is then adjusted according to the required residual chlorine. At last, since it has few side effects and relatively low operating costs, UV dose is determined by the remaining requirement of microbial indicator reduction. By this method, the effluent of disinfection could meet the discharge standards of colority, residual chlorine, and microbial indicators. The operating cost was reduced by 48.7%, mainly by lowering the ozone dosage. The production of disinfection by-products (DBPs) was effectively controlled by decreasing the chlorine dosage compared with the original working conditions in the plant. Moreover, ozone pretreatment effectively improved the coliform inactivation efficiency of chlorine, and the combined disinfection method alleviated the tailing phenomenon and achieved a higher maximum log reduction of coliforms. The proposed method can help water reclamation plants reasonably determine operational loads between disinfection units with low cost and guaranteed performance.
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Affiliation(s)
- Fan-Qin Wei
- 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 724, 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 724, 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 724, 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 724, Beijing 100084, China
| | - Kui-Xiao Li
- Research and Development Center, Beijing Drainage Group Co., Ltd, Beijing 100124, China
| | - Ting 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, Room 724, Beijing 100084, China; School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Yu-Long Shi
- Research and Development Center, Beijing Drainage Group Co., Ltd, Beijing 100124, China
| | - Qi Xu
- Research and Development Center, Beijing Drainage Group Co., Ltd, Beijing 100124, 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 724, Beijing 100084, China; Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Shenzhen 518055, China
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29
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Sporicidal mechanism of the combination of ortho-phthalaldehyde and benzyldimethyldodecylammonium chloride as a disinfectant against the Bacillus subtilis spores. Braz J Microbiol 2022; 53:547-556. [PMID: 35143017 PMCID: PMC9151947 DOI: 10.1007/s42770-022-00695-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 02/01/2022] [Indexed: 02/01/2023] Open
Abstract
Previous studies have shown that the combination disinfectant, Ortho-phthalaldehyde and benzyldimethyldodecylammonium chloride (ODB), can effectively kill a variety of microorganisms, such as Escherichia coli, Staphylococcus aureus, and Candida albicans. To observe the sporicidal ability and mechanism of ODB for spores, Bacillus subtilis spores were used as the research object in this experiment. TEM images revealed that ODB destroyed the integrity of the coat, cortex, and inner membrane of the spores after 0.5-h treatment, and the nuclear material was also broken and exuded after 4-h treatment. The broken structure led to the release of dipicolinic acid (DPA) in large amount. The results show that B. subtilis spores can be effetely killed by ODB through destroying the structure of the spores.
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30
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Wan Q, Cao R, Wen G, Xu X, Xia Y, Wu G, Li Y, Wang J, Lin Y, Huang T. Sequential use of UV-LEDs irradiation and chlorine to disinfect waterborne fungal spores: Efficiency, mechanism and photoreactivation. JOURNAL OF HAZARDOUS MATERIALS 2022; 423:127102. [PMID: 34482083 DOI: 10.1016/j.jhazmat.2021.127102] [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: 06/20/2021] [Revised: 08/18/2021] [Accepted: 08/29/2021] [Indexed: 06/13/2023]
Abstract
In this work, sequential applications of light-emitting diodes (UV-LEDs) with two wavelengths and chlorine (Cl2) were performed for fungal spores disinfection: UV-Cl2, Cl2-UV, UV/Cl2-UV, UV-UV/Cl2, Cl2-UV/Cl2-Cl2. Overall comparisons of the sequential processes with respect to the inhibitory effect on photoreactivation were also evaluated. According to the evaluation of culturability and membrane permeability, inactivation of fungal spores by UV was not enhanced by prior or post exposure to Cl2, but in the UV/Cl2 process with pre or post UV treatment, the inactivation efficiency was greatly enhanced. Take P. polonicum for example, pre-treatments by UV265 and UV280 (40 mJ/cm2) caused the log count reduction (LCR) of 1.05 log and 0.95 log, then the followed UV265/Cl2 and UV280/Cl2 at the same UV fluence caused additional LCR of 1.80 log and 2.00 log. The permeabilization of P. polonicum was also accelerated in the processes of UV/Cl2-UV and UV-UV/Cl2, especially at the wavelength of 280 nm. In the sequential processes, especially those containing UV/Cl2 or at the wavelength of 280 nm, could promote the formation of intracellular reactive oxygen species (ROS), thus leading to more severe damage to the spores as reflected in the culturability reduction, membrane permeability and inhibition of photoreactivation.
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Affiliation(s)
- Qiqi Wan
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Ruihua Cao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Gang Wen
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, PR China.
| | - Xiangqian Xu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Yuancheng Xia
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Gehui Wu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Yangfan Li
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Jingyi Wang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Yingzi Lin
- School of Municipal and Environmental Engineering, Jilin Jianzhu University, Changchun 130118, PR China
| | - Tinglin Huang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
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Wan Q, Cao R, Wen G, Xu X, Xia Y, Wu G, Li Y, Wang J, Xu H, Lin Y, Huang T. Efficacy of UV-LED based advanced disinfection processes in the inactivation of waterborne fungal spores: Kinetics, photoreactivation, mechanism and energy requirements. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 803:150107. [PMID: 34525763 DOI: 10.1016/j.scitotenv.2021.150107] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 08/14/2021] [Accepted: 08/30/2021] [Indexed: 06/13/2023]
Abstract
The contamination of fungi in water supply systems poses great risks to environment and human health. In this work, UV light-emitting diodes (UV-LEDs)-based advanced disinfection processes (ADPs) including UV-LEDs/hydrogen peroxide (H2O2), UV-LEDs/persulfate (PS) and UV-LEDs/peroxymonosulfate (PMS), were adopted for waterborne fungal spores inactivation. Overall comparisons of the UV-LEDs-based ADPs with respect to the control efficiency of photoreactivation and energy consumption were also evaluated. Results showed that culturability reduction of the fungal spores treated by UV-LEDs was not enhanced with the addition H2O2, PMS, and PS according to the results of heterotrophic plate counts and reaction rate constants; A. niger was expected to have higher UV resistance followed by T. harzianum and P. polonicum. However, UV-LEDs-ADPs inactivation, especially at the wavelengths of 280 and 265/280 nm, could accelerate the permeabilization of fungal spores as characterized by flow cytometry. Take P. polonicum for example, the percentage of membrane permeabilized spores was 98.0%, 98.7%, 97.6% and 82.6% after treatment by UV280/H2O2, UV280/PS, UV280/PMS and UV280 alone, respectively at the fluence of 100 mJ/cm2. The direct attack of free radicals in the processes of UV-LEDs-ADPs further enhanced the membrane damage and lowered the photoreactivation level, thus improved the inactivation efficiency. UV-LEDs/H2O2 was considered as an effective process in the disinfection of fungal spores with the advantages of enhancing the damage of membrane, inhibiting photoreactivation and comparable energy consumption compared with UV-LEDs alone.
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Affiliation(s)
- Qiqi Wan
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Ruihua Cao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Gang Wen
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, PR China.
| | - Xiangqian Xu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Yuancheng Xia
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Gehui Wu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Yangfan Li
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Jingyi Wang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Huining Xu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Yingzi Lin
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; School of Municipal and Environmental Engineering, Jilin Jianzhu University, Changchun 130118, PR China
| | - Tinglin Huang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
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Li GQ, Huo ZY, Wu QY, Chen Z, Wu YH, Lu Y, Hu HY. Photolysis of free chlorine and production of reactive radicals in the UV/chlorine system using polychromatic spectrum LEDs as UV sources. CHEMOSPHERE 2022; 286:131828. [PMID: 34416584 DOI: 10.1016/j.chemosphere.2021.131828] [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: 05/28/2021] [Revised: 08/02/2021] [Accepted: 08/05/2021] [Indexed: 06/13/2023]
Abstract
Recently, ultraviolet light-emitting diodes (UV-LEDs) and chlorine combined system has been employed as an emerging advanced oxidation process. However, UV-LEDs were commonly considered as monochromatic UV sources. In this study, the obvious quantum yields of chlorine photolysis under 265 nm and 280 nm LEDs irradiations were investigated with treating LEDs as polychromatic UV sources. Particularly, Φobs-poly of HOCl and OCl⁻ for 265 nm LED were found to be 1.50 and 0.70 mol E-1, respectively, whereas Φobs-poly of HOCl and OCl⁻ for 280 nm LED were 1.28 and 0.64 mol E-1, respectively. It was identified that Φobs-poly were 5.66-14.63 % lower than Φobs-mono. This suggests that obvious quantum yield using peak emission wavelength would overestimate the true quantum yield. The production of radical species in LED UV/chlorine systems were determined by the degradation of BA, and illustrated by a mathematical model. Different trends were observed for 265 nm and 280 nm LED UV/chlorine systems as pH increased from 5.0 to 10.0. As pH increased, the formation of OH continuously decreased in both 265 nm and 280 nm LED systems. The formation of Cl increased at neutral pH and more Cl and OH were formed due to the higher molar absorbance coefficient at 280 nm. The chlorine dose-dependent effects on radical productions at pH of 5.0, 7.5 and 10.0 were also assessed. At pH of 5.0, OH was the main radical product and had linear correlation with chlorine dose. At pH of 7.5, the productions of OH and Cl showed similar profiles that increased rapidly at low chlorine dosage and then slowed down.
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Affiliation(s)
- Guo-Qiang Li
- School of Ecology and Environment, Zhengzhou University, Zhengzhou, 450001, PR China; Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Zheng-Yang Huo
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Qian-Yuan Wu
- Shenzhen Laboratory of Microorganism Application and Risk Control, Graduate School at Shenzhen, 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), Beijing Laboratory for Environmental Frontier Technologies, 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), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, 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), Beijing Laboratory for Environmental Frontier Technologies, 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), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing, 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Suzhou, 215163, PR China.
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Nunayon SS, Zhang HH, Chan V, Kong RYC, Lai ACK. Study of synergistic disinfection by UVC and positive/negative air ions for aerosolized Escherichia coli, Salmonella typhimurium, and Staphylococcus epidermidis in ventilation duct flow. INDOOR AIR 2022; 32:e12957. [PMID: 34796996 DOI: 10.1111/ina.12957] [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: 03/21/2021] [Revised: 10/29/2021] [Accepted: 10/30/2021] [Indexed: 06/13/2023]
Abstract
The efficacy of the in-duct application of ultraviolet waveband C (UVC) emitting at 254 nm wavelength and air ions against aerosolized bacteria was studied in a full-scale 9-m long ventilation duct. Combined positive and negative ion polarities (bipolar ions) and combined UVC and ions were tested. The UVC was generated by a mercury-type UVC lamp and air ions were generated by positive and negative polarity ionizers. Escherichia coli (E. coli), Salmonella typhimurium (S. typhimurium), and Staphylococcus epidermidis (S. epidermidis)were tested at a concentration of 108 to 109 cells in 50 ml of sterilized distilled water. The case in which the positive ionizer was placed first, followed by the negative ionizer, demonstrated significantly higher disinfection efficiencies for E. coli (p = 0.007) and S. typhimurium (p < 0.001), but lower efficiency for S. epidermidis (p = 0.01) than the reversed sequence. The combination of UVC (3.71 J/m2 ) and air ions (1.13 × 1012 ions/m3 for positive ions and 8.00 × 1011 ions/m3 for negative ions) led to higher inactivation than individual disinfection agents operating under the same dose. A synergetic inactivation effect was observed for S. epidermidis under the combined UVC and positive ion case, while the combined UVC and negative ion case showed significant synergy effects for E. coli and S. typhimurium.
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Affiliation(s)
- Sunday S Nunayon
- Department of Architecture and Civil Engineering, City University of Hong Kong, Hong Kong, China
| | - Hui H Zhang
- Department of Architecture and Civil Engineering, City University of Hong Kong, Hong Kong, China
| | - Vincent Chan
- Department of Biomedical Engineering, Khalifa University of Science and Technology, Abu Dhabi, UAE
| | - Richard Y C Kong
- Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - Alvin C K Lai
- Department of Architecture and Civil Engineering, City University of Hong Kong, Hong Kong, China
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Lv R, Liu D, Zhou J. Bacterial spore inactivation by non-thermal technologies: resistance and inactivation mechanisms. Curr Opin Food Sci 2021. [DOI: 10.1016/j.cofs.2020.12.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Lv R, Liu D, Wang W, Xu E, Ding T, Ye X, Zhou J. Proteomic response and molecular regulatory mechanisms of Bacillus cereus spores under ultrasound treatment. ULTRASONICS SONOCHEMISTRY 2021; 78:105732. [PMID: 34474268 PMCID: PMC8411229 DOI: 10.1016/j.ultsonch.2021.105732] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 08/03/2021] [Accepted: 08/17/2021] [Indexed: 05/03/2023]
Abstract
This study was aimed at providing new insights on the proteomic response of bacterial spores to ultrasound. Data-independent-acquisition method was used to quantify the proteome change of Bacillus cereus spores after ultrasound treatment (200 W). This study revealed that 2485 proteins were extracted from Bacillus cereus spores, most of them were related to metabolism. After ultrasound treatment, the expression of 340 proteins were significantly changed (the fold change ≥ 2 and p < 0.05), of which 207 proteins were significantly down-regulated. KEGG pathway analysis showed that differentially expressed proteins mainly distributed in metabolism pathway, cell process pathway and genetic information processing pathway after ultrasound treatment. Furthermore, this study analyzed the differentially expressed proteins in significant enrichment pathways. In particular, the expression of key proteins in the phosphorylation reaction of spores was significantly decreased after ultrasound treatment. Thus, ATP synthesis rate decreased and the phosphorylation reaction inhibited. Also, the decrease of the expression of key proteins related to the tricarboxylic acid cycle led to the decrease of nutrients metabolism of spores. Ultrasound treatment induced the down-regulation of fatty acid synthetase expression and promoted fatty acid metabolism at the same time. The content of fatty acids decreased in spores consequently.
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Affiliation(s)
- Ruiling Lv
- NingboTech University, Ningbo 315100, China; Ningbo Research Institute, Zhejiang University, Ningbo 315100, China; College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China
| | - Donghong Liu
- Ningbo Research Institute, Zhejiang University, Ningbo 315100, China; College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China
| | - Wenjun Wang
- Ningbo Research Institute, Zhejiang University, Ningbo 315100, China; College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China
| | - Enbo Xu
- Ningbo Research Institute, Zhejiang University, Ningbo 315100, China; College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China
| | - Tian Ding
- Ningbo Research Institute, Zhejiang University, Ningbo 315100, China; College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China
| | - Xingqian Ye
- Ningbo Research Institute, Zhejiang University, Ningbo 315100, China; College of Biosystems Engineering and Food Science, National-Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China
| | - Jianwei Zhou
- NingboTech University, Ningbo 315100, China; Ningbo Research Institute, Zhejiang University, Ningbo 315100, China.
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Song H, Lee JY, Lee HW, Ha JH. Inactivation of bacteria causing soft rot disease in fresh cut cabbage using slightly acidic electrolyzed water. Food Control 2021. [DOI: 10.1016/j.foodcont.2021.108217] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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37
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Huo ZY, Lee DM, Kim YJ, Kim SW. Solar-induced hybrid energy harvesters for advanced oxidation water treatment. iScience 2021; 24:102808. [PMID: 34308295 PMCID: PMC8283326 DOI: 10.1016/j.isci.2021.102808] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Water treatment based on advanced oxidation processes (AOPs) supplies clean water to rural areas lacking electric power supply and/or during natural disasters and pandemics. Considering the abundance of solar energy in the ambient environment, the solar-driven AOPs show an interesting potential to driving the water purification process. Involving the energy harvester (EH) that harvests mechanical or thermal energy into electricity to the solar-driven AOPs can achieve sustainable and self-powered water purification. Herein, we summarize the recent progress in the application of solar-induced hybrid EHs that harvest solar and mechanical/thermal energy simultaneously to drive AOP water treatment. A detailed discussion of the solar-induced hybrid EHs enabling AOP water treatment based on the mechanisms of piezo-, tribo-, pyro-, and thermo-assisted photocatalysis is provided. In addition, this paper explores future opportunities and strategies of the solar-induced hybrid EHs to drive the AOP water treatment in actual situations with unstable and fluctuating environmental conditions.
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Affiliation(s)
- Zheng-Yang Huo
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Dong-Min Lee
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Young-Jun Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Sang-Woo Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea.,SKKU Advanced Institute of Nanotechnology (SAINT), Samsung Advanced Institute for Health Sciences & Technology (SAIHST), Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
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Zhang T, Lv K, Lu Q, Wang L, Liu X. Removal of antibiotic-resistant genes during drinking water treatment: A review. J Environ Sci (China) 2021; 104:415-429. [PMID: 33985744 DOI: 10.1016/j.jes.2020.12.023] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 12/14/2020] [Accepted: 12/21/2020] [Indexed: 06/12/2023]
Abstract
Once contaminate the drinking water source, antibiotic resistance genes (ARGs) will propagate in drinking water systems and pose a serious risk to human health. Therefore, the drinking water treatment processes (DWTPs) are critical to manage the risks posed by ARGs. This study summarizes the prevalence of ARGs in raw water sources and treated drinking water worldwide. In addition, the removal efficiency of ARGs and related mechanisms by different DWTPs are reviewed. Abiotic and biotic factors that affect ARGs elimination are also discussed. The data on presence of ARGs in drinking water help come to the conclusion that ARGs pollution is prevalent and deserves a high priority. Generally, DWTPs indeed achieve ARGs removal, but some biological treatment processes such as biological activated carbon filtration may promote antibiotic resistance due to the enrichment of ARGs in the biofilm. The finding that disinfection and membrane filtration are superior to other DWTPs adds weight to the advice that DWTPs should adopt multiple disinfection barriers, as well as keep sufficient chlorine residuals to inhibit re-growth of ARGs during subsequent distribution. Mechanistically, DWTPs obtain direct and inderect ARGs reduction through DNA damage and interception of host bacterias of ARGs. Thus, escaping of intracellular ARGs to extracellular environment, induced by DWTPs, should be advoided. This review provides the theoretical support for developping efficient reduction technologies of ARGs. Future study should focus on ARGs controlling in terms of transmissibility or persistence through DWTPs due to their biological related nature and ubiquitous presence of biofilm in the treatment unit.
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Affiliation(s)
- Tuqiao Zhang
- Zhejiang Key Laboratory of Drinking Water Safety and Distribution Technology, Zhejiang University, Hangzhou 310058, China
| | - Kunyuan Lv
- Zhejiang Key Laboratory of Drinking Water Safety and Distribution Technology, Zhejiang University, Hangzhou 310058, China
| | - Qingxiao Lu
- Ocean College, Zhejiang University, Hangzhou 310058, China
| | - Lili Wang
- Environmental Engineering, Jiyang College of Zhejiang A & F University, Zhuji 311800, China
| | - Xiaowei Liu
- Zhejiang Key Laboratory of Drinking Water Safety and Distribution Technology, Zhejiang University, Hangzhou 310058, China; Ocean College, Zhejiang University, Hangzhou 310058, China.
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Shi Q, Chen Z, Liu H, Lu Y, Li K, Shi Y, Mao Y, Hu HY. Efficient synergistic disinfection by ozone, ultraviolet irradiation and chlorine in secondary effluents. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 758:143641. [PMID: 33261863 DOI: 10.1016/j.scitotenv.2020.143641] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/08/2020] [Accepted: 11/09/2020] [Indexed: 05/03/2023]
Abstract
Disinfection of secondary effluents is vital to provide a sustainable aquatic environment, minimize microbial risks and guarantee public and environmental safety. This study investigated the effectiveness of six treatment trains including single and combined disinfection processes (i.e., ozone alone, ultraviolet (UV) irradiation alone, chlorine alone, sequential ozone-UV, sequential ozone-chlorine and sequential ozone-UV-chlorine) on bacterial inactivation, as well as bulk water quality parameters such as color, turbidity, absorbance at 254 nm (UV254), dissolved organic carbon (DOC) and fluorescence based on samples collected from an actual water reclamation plant (WRP). For the single disinfection processes, when the ozone, UV and chlorine doses reached 5 mg/L, 15 mJ/cm2 and 4 mg/L, respectively, the log removal of Escherichia coli (E. coli) reached 5 log. A trailing phenomenon was observed with further increases in the disinfectant dosage. Under the combined treatment scenarios, ozone pretreatment resulted in substantial removal of color, turbidity, UV254, fluorescence excitation-emission matrix (FEEM) and chlorine consuming organics, thus enhancing the efficiency of subsequent UV irradiation or chlorine treatments. In the sequential ozone-UV-chlorine experiments, E. coli inactivation reached 7 log with ozone, UV and available chlorine of 3 mg/L, 5 or 10 mJ/cm2 and 2.5 mg/L, respectively. On the basis of the results from the actual WRP, the estimated operating cost per unit for the disinfection systems is 0.065 CNY/t, which is economical for long-term operation.
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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; 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.
| | - 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; School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, Jinan University, Guangzhou 510632, PR China; Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, 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
| | - Kuixiao Li
- Research and Development Center, Beijing Drainage Group Co., Ltd, Beijing 100124, PR China
| | - Yulong Shi
- Research and Development Center, Beijing Drainage Group Co., Ltd, Beijing 100124, 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
| | - 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; Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Shenzhen 518055, PR China.
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40
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Farag MA, Mesak MA, Saied DB, Ezzelarab NM. Uncovering the dormant food hazards, a review of foodborne microbial spores' detection and inactivation methods with emphasis on their application in the food industry. Trends Food Sci Technol 2021. [DOI: 10.1016/j.tifs.2020.10.037] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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41
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Kebbi Y, Muhammad AI, Sant'Ana AS, do Prado‐Silva L, Liu D, Ding T. Recent advances on the application of UV‐LED technology for microbial inactivation: Progress and mechanism. Compr Rev Food Sci Food Saf 2020; 19:3501-3527. [DOI: 10.1111/1541-4337.12645] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 08/29/2020] [Accepted: 09/16/2020] [Indexed: 12/13/2022]
Affiliation(s)
- Yasmine Kebbi
- College of Biosystems Engineering and Food Science National‐Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment Zhejiang Key Laboratory for Agro‐Food Processing Zhejiang University Hangzhou China
| | - Aliyu Idris Muhammad
- College of Biosystems Engineering and Food Science National‐Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment Zhejiang Key Laboratory for Agro‐Food Processing Zhejiang University Hangzhou China
- Department of Agricultural and Environmental Engineering Faculty of Engineering Bayero University Kano Nigeria
| | - Anderson S. Sant'Ana
- Department of Food Science Faculty of Food Engineering University of Campinas Campinas SP Brazil
| | | | - Donghong Liu
- College of Biosystems Engineering and Food Science National‐Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment Zhejiang Key Laboratory for Agro‐Food Processing Zhejiang University Hangzhou China
- Ningbo Research Institute Zhejiang University Ningbo China
| | - Tian Ding
- College of Biosystems Engineering and Food Science National‐Local Joint Engineering Laboratory of Intelligent Food Technology and Equipment Zhejiang Key Laboratory for Agro‐Food Processing Zhejiang University Hangzhou China
- Ningbo Research Institute Zhejiang University Ningbo China
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42
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Wan Q, Wen G, Cao R, Zhao H, Xu X, Xia Y, Wu G, Lin W, Wang J, Huang T. Simultaneously enhance the inactivation and inhibit the photoreactivation of fungal spores by the combination of UV-LEDs and chlorine: Kinetics and mechanisms. WATER RESEARCH 2020; 184:116143. [PMID: 32688151 DOI: 10.1016/j.watres.2020.116143] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 06/30/2020] [Accepted: 07/02/2020] [Indexed: 06/11/2023]
Abstract
Waterborne fungi have been recognized as an emerging environmental contaminant in recent years. This work was to investigate the inactivation efficiency and mechanisms of ultraviolet light-emitting diodes (UV-LEDs)/chlorine (Cl2) (265, 280 and 265/280 nm combination) and LPUV/Cl2 (254 nm) treatments for three fungal species compared with individual disinfection processes. Control of photoreactivation for fungal species inactivated by UV-LEDs/Cl2 and LPUV/Cl2 was also evaluated. The results revealed that the combined UV-LEDs/Cl2 and LPUV/Cl2 processes, especially UV-LEDs/Cl2, exhibited better inactivation performance compared to UV alone and Cl2 alone based on the inactivation rate constants, and an evident synergistic effect was observed. For example, the inactivation rates for Penicillium polonicum in the processes of UV265/Cl2, UV280/Cl2, UV265/280/Cl2 and LPUV/Cl2 was 0.142, 0.168, 0.174 and 0.106 cm2/mJ, respectively, which were all approximately 1.5-fold higher than that of UV alone. The synergistic effect of fungal spores inactivation by UV-LEDs/Cl2 and LPUV/Cl2 was due to the high level production of intracellular reactive oxygen species and the reaction of potential extracellular free radicals. Resistance of the tested fungal spores was as follows: Trichoderma harzianum < Penicillium polonicum < Aspergillus niger. In addition, the joint effect of DNA and other cellular damage resulted in the inhibition of photoreactivation of fungal spores inactivated by UV-LEDs/Cl2 and LPUV/Cl2 compared with that of fungal spore inactivated by UV alone. This study may provide reference for controlling the dissemination of waterborne fungi utilizing combined UV-LEDs and free chlorine processes.
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Affiliation(s)
- Qiqi Wan
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Gang Wen
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China.
| | - Ruihua Cao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Hui Zhao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Xiangqian Xu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Yuancheng Xia
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Gehui Wu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Wei Lin
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Jingyi Wang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Tinglin Huang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
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Jiang Y, Ai C, Liao X, Liu D, Ding T. Effect of slightly acidic electrolyzed water (SAEW) and ultraviolet light illumination pretreatment on microflora inactivation of coriander. Lebensm Wiss Technol 2020. [DOI: 10.1016/j.lwt.2020.109898] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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44
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Zhai Y, Tian J, Ping R, Xiu H, Xiang Q, Shen R, Wang Z. Effects of ultraviolet-C light-emitting diodes at 275 nm on inactivation of Alicyclobacillusacidoterrestris vegetative cells and its spores as well as the quality attributes of orange juice. FOOD SCI TECHNOL INT 2020; 27:334-343. [PMID: 32954800 DOI: 10.1177/1082013220957529] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Alicyclobacillus acidoterrestris is a thermoacidophilic, spore-forming bacillus. A. acidoterrestris and its spores can survive in pasteurized juices and cause microbial spoilage. In this work, the effects of ultraviolet-C light-emitting diodes at 275 nm on the inactivation of A. acidoterrestris vegetative cells and its spores in commercial pasteurized orange juice were studied. Meanwhile, the effects of ultraviolet-C light-emitting diodes on the quality attributes of the orange juice were also investigated. The quantities of A. acidoterrestris vegetative cells and its spores inoculated in orange juice were reduced by 6.04 and 2.49 log10 CFU/mL after ultraviolet-C light-emitting diode treatment at 220 mJ/cm2, respectively. The Weibull and Weibull plus tail models were satisfactorily fitted to estimate the reductions of A. acidoterrestris vegetative cells and its spores in orange juice, respectively. Physicochemical properties (pH, titratable acidity, total soluble solids, and clarity) of orange juice did not change significantly after exposure to ultraviolet-C light-emitting diodes. However, the total phenolic content of orange juice decreased with increasing fluence. In addition, ultraviolet-C light-emitting diode treatment at a higher fluence led to a noticeable color difference. These results indicate that ultraviolet-C light-emitting diode treatment has a potential application in the juice processing industry.
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Affiliation(s)
- Yafei Zhai
- College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, PR China.,Henan Key Laboratory of Cold Chain Food Quality and Safety Control, Zhengzhou, PR China.,Henan Collaborative Innovation Center of Food Production and Safety, Zhengzhou, PR China
| | - Jiali Tian
- College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, PR China
| | - Ruonan Ping
- College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, PR China
| | - Hongxia Xiu
- College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, PR China
| | - Qisen Xiang
- College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, PR China.,Henan Key Laboratory of Cold Chain Food Quality and Safety Control, Zhengzhou, PR China.,Henan Collaborative Innovation Center of Food Production and Safety, Zhengzhou, PR China
| | - Ruiling Shen
- College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, PR China.,Henan Key Laboratory of Cold Chain Food Quality and Safety Control, Zhengzhou, PR China.,Henan Collaborative Innovation Center of Food Production and Safety, Zhengzhou, PR China
| | - Zhangcun Wang
- College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, PR China.,Henan Key Laboratory of Cold Chain Food Quality and Safety Control, Zhengzhou, PR China.,Henan Collaborative Innovation Center of Food Production and Safety, Zhengzhou, PR China
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45
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Prasad A, Du L, Zubair M, Subedi S, Ullah A, Roopesh MS. Applications of Light-Emitting Diodes (LEDs) in Food Processing and Water Treatment. FOOD ENGINEERING REVIEWS 2020. [PMCID: PMC7223679 DOI: 10.1007/s12393-020-09221-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Light-emitting diode (LED) technology is an emerging nonthermal food processing technique that utilizes light energy with wavelengths ranging from 200 to 780 nm. Inactivation of bacteria, viruses, and fungi in water by LED treatment has been studied extensively. LED technology has also shown antimicrobial efficacy in food systems. This review provides an overview of recent studies of LED decontamination of water and food. LEDs produce an antibacterial effect by photodynamic inactivation due to photosensitization of light absorbing compounds in the presence of oxygen and DNA damage; however, such inactivation is dependent on the wavelength of light energy used. Commercial applications of LED treatment include air ventilation systems in office spaces, curing, medical applications, water treatment, and algaculture. As low penetration depth and high-intensity usage can challenge optimal LED treatment, optimization studies are required to select the right light wavelength for the application and to standardize measurements of light energy dosage.
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Affiliation(s)
- Amritha Prasad
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2P5 Canada
| | - Lihui Du
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2P5 Canada
| | - Muhammad Zubair
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2P5 Canada
| | - Samir Subedi
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2P5 Canada
| | - Aman Ullah
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2P5 Canada
| | - M. S. Roopesh
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2P5 Canada
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46
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Wan Q, Wen G, Cao R, Xu X, Zhao H, Li K, Wang J, Huang T. Comparison of UV-LEDs and LPUV on inactivation and subsequent reactivation of waterborne fungal spores. WATER RESEARCH 2020; 173:115553. [PMID: 32028247 DOI: 10.1016/j.watres.2020.115553] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 01/22/2020] [Accepted: 01/25/2020] [Indexed: 06/10/2023]
Abstract
Recently, the contamination of fungi in water supply systems has been an area of increasing concern, such as Aspergillus spp. and Penicillium spp. It can cause some waterborne issues such as odor, taste and formation of mycotoxins. Ultraviolet light emitting diodes (UV-LEDs) are considered as a potential alternative to conventional mercury lamps for water disinfection. This study has compared the performance of LPUV (low pressure ultraviolet) and UV-LEDs with emissions at 265, 280 nm and combination emissions at 265/280 nm to test inactivation efficiency, reactivation, viability and electrical energy consumption in the treatment of three water-borne fungal species (Aspergillus niger, Penicillium polonicum, Trichoderma harzianum) at a batch water disinfection system. The results showed that the performances of UV-LEDs were superior for the inactivation of fungal spores compared to the 254 nm (LP), while no statistically differences were observed among the UV-LEDs (p > 0.05). The average photoreactivation rate (k1) of fungal spores irradiated by UV-LEDs and 254 nm (LP) follows the order: T. harzianum > A. niger > P. polonicum. Compared with LPUV, UV-LEDs irradiation at 280 nm and 265/280 nm more efficiently inhibits photoreactivation, which was attributed to that irradiation of 280 nm and 265/280 nm would cause greater membrane damage and increase intracellular reactive oxygen species level of fungal spores according to the flow cytometric results. The electrical energy consumption of UV-LEDs was higher than that of LPUV, which was due to its lower wall plug efficiency. The results of this study can provide additional and beneficial information for the reasonable exploitation of UV-LEDs in water disinfection.
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Affiliation(s)
- Qiqi Wan
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Gang Wen
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China.
| | - Ruihua Cao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Xiangqian Xu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Hui Zhao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Kai Li
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Jingyi Wang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Tinglin Huang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
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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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48
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Zhu Z, Shan L, Hu F, Li Z, Zhong D, Yuan Y, Zhang J. Biofilm formation potential and chlorine resistance of typical bacteria isolated from drinking water distribution systems. RSC Adv 2020; 10:31295-31304. [PMID: 35520667 PMCID: PMC9056398 DOI: 10.1039/d0ra04985a] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 08/17/2020] [Indexed: 11/30/2022] Open
Abstract
Biofilms are the main carrier of microbial communities throughout drinking water distribution systems (DWDSs), and strongly affect the safety of drinking water. Understanding biofilm formation potential and chlorine resistance is necessary for exploring future disinfection strategies and preventing water-borne diseases. This study investigated biofilm formation of five bacterial strains isolated from a simulated DWDS at different incubation times (24 h, 48 h, and 72 h), then evaluated chlorine resistance of 72 h incubated biofilms under chlorine concentrations of 0.3, 0.6, 1, 2, 4, and 10 mg L−1. All five bacterial strains had biofilm formation potential when incubated for 72 h. The biofilm formation potential of Acinetobacter sp. was stronger than that of Bacillus cereus, Microbacterium sp. and Sphingomonas sp. were moderate, and that of Acidovorax sp. was weak. In contrast, the order of chlorine resistance was Bacillus sp. > Sphingomonas sp. > Microbacterium sp. > Acidovorax sp. > Acinetobacter sp. Thus, the chlorine resistance of a single-species biofilm has little relation with the biofilm formation potential. The biofilm biomass is not a major factor affecting chlorine resistance. Moreover, the chlorine resistance of a single-species biofilm is highly related to the physiological state of bacterial cells, such as their ability to form spores or secrete extracellular polymeric substances, which could reduce the sensitivity of the single-species biofilm to a disinfectant or otherwise protect the biofilm. Biofilms are the main carrier of microbial communities throughout drinking water distribution systems (DWDSs), and strongly affect the safety of drinking water.![]()
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Affiliation(s)
- Zebing Zhu
- School of Civil Engineering and Architecture
- East China Jiao Tong University
- Nanchang
- China
- State Key Laboratory of Urban Water Resource and Environment
| | - Lili Shan
- School of Civil Engineering and Architecture
- East China Jiao Tong University
- Nanchang
- China
| | - Fengping Hu
- School of Civil Engineering and Architecture
- East China Jiao Tong University
- Nanchang
- China
| | - Zehua Li
- School of Civil Engineering and Architecture
- East China Jiao Tong University
- Nanchang
- China
| | - Dan Zhong
- State Key Laboratory of Urban Water Resource and Environment
- School of Environment
- Harbin Institute of Technology
- Harbin
- China
| | - Yixing Yuan
- State Key Laboratory of Urban Water Resource and Environment
- School of Environment
- Harbin Institute of Technology
- Harbin
- China
| | - Jie Zhang
- State Key Laboratory of Urban Water Resource and Environment
- School of Environment
- Harbin Institute of Technology
- Harbin
- China
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49
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Bing S, Zang YT, Li YJ, Shu DQ. The synergistic effects of slightly acidic electrolyzed water and UV-C light on the inactivation of Salmonella enteritidis on contaminated eggshells. Poult Sci 2019; 98:6914-6920. [PMID: 31392328 PMCID: PMC8913955 DOI: 10.3382/ps/pez454] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 07/25/2019] [Indexed: 12/02/2022] Open
Abstract
Salmonella enteritidis (S. enteritidis) infection has been recognized as one of the most common bacterial causes of human gastroenteritis worldwide and is closely associated with eggs. Slightly acidic electrolyzed water (SAEW) is an emerging environmentally friendly technology for disinfecting eggshell surfaces to remove dirt and pathogenic microorganisms. However, the efficiency of SAEW could be affected by the presence of manure. UV-based advanced oxidation processes have been studied to improve the microorganism's inactivation effect of disinfection. Therefore, in this study, the synergistic bactericidal efficacy of SAEW and UV-C light (ultraviolet lamp, λ = 254 nm) for inactivation of S. enteritidis on artificially inoculated eggshells with or without manure was evaluated, and the bactericidal efficacy of different combination treatments of SAEW and UV-C light was compared. Without manure interference, complete inactivation (reduction of 6.54 log10 CFU/g) of S. enteritidis on the surface of eggshells was achieved following a 4-min treatment with SAEW+UV at an available chlorine concentration (ACC) of 20 mg/L. In the presence of manure, a 3.02 log reduction was achieved following a 4-min treatment with SAEW+UV at an ACC of 30 mg/L. Simultaneous treatment with SAEW and UV light exhibits higher bactericidal activity for eggshells than other combination process methods with UV and SAEW. The results suggest that the combined treatment of SAEW+UV is a novel method to enhance the microbial safety of eggshells.
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Affiliation(s)
- Sh Bing
- Jiangxi Agricultural University, Jiangxi 330045, China
| | - Y T Zang
- Jiangxi Agricultural University, Jiangxi 330045, China
| | - Y J Li
- Jiangxi Agricultural University, Jiangxi 330045, China
| | - D Q Shu
- Jiangxi Agricultural University, Jiangxi 330045, China
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50
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Umar M, Roddick F, Fan L. Moving from the traditional paradigm of pathogen inactivation to controlling antibiotic resistance in water - Role of ultraviolet irradiation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 662:923-939. [PMID: 30795480 DOI: 10.1016/j.scitotenv.2019.01.289] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 01/21/2019] [Accepted: 01/22/2019] [Indexed: 06/09/2023]
Abstract
Ultraviolet (UV) irradiation has proven an effective tool for inactivating microorganisms in water. There is, however, a need to look at disinfection from a different perspective because microbial inactivation alone may not be sufficient to ensure the microbiological safety of the treated water since pathogenic genes may still be present, even after disinfection. Antibiotic resistance genes (ARGs) are of a particular concern since they enable microorganisms to become resistant to antibiotics. UV irradiation has been widely used for disinfection and more recently for destroying ARGs. While UV lamps remain the principal technology to achieve this objective, UV light emitting diodes (UV-LEDs) are novel sources of UV irradiation and have increasingly been reported in lab-scale investigations as a potential alternative. This review discusses the current state of the applications of UV technology for controlling antibiotic resistance during water and wastewater treatment. Since UV-LEDs possess several attractive advantages over conventional UV lamps, the impact of UV-LED characteristics (single vs combined wavelengths, and operational parameters such as periodic or pulsed and continuous irradiation, pulse repetition frequencies, duty cycle), type of organism, and fluence response, are critically reviewed with a view to highlighting the research needs for addressing future disinfection challenges. The energy efficiency of the reported UV processes is also evaluated with a focus on relating the findings to disinfection efficacy. The greater experience with UV lamps could be useful for investigating UV-LEDs for similar applications (i.e., antibiotic resistance control), and hence identification of future research directions.
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Affiliation(s)
- Muhammad Umar
- Norwegian Institute for Water Research (NIVA), Gaustadallèen 21, NO-0349 Oslo, Norway.
| | - Felicity Roddick
- Department of Chemical and Environmental Engineering, School of Engineering, RMIT University, Melbourne 3001, Australia
| | - Linhua Fan
- Department of Chemical and Environmental Engineering, School of Engineering, RMIT University, Melbourne 3001, Australia
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