1
|
Zhang C, Sienkiewicz N, Struewing I, Mistry JH, Buse H, Hu Z, Lu J. Reconsider the burn: The transient effect of a chlorine burn on controlling opportunistic pathogens in a full-scale chloraminated engineered water system. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 933:172690. [PMID: 38670361 DOI: 10.1016/j.scitotenv.2024.172690] [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: 12/19/2023] [Revised: 04/20/2024] [Accepted: 04/20/2024] [Indexed: 04/28/2024]
Abstract
Nitrification is a serious water-quality issue in chloraminated engineered water systems (EWSs). Nitrification is often remediated by a chlorine burn (i.e., a free‑chlorine conversion), a short-term switch from chloramination to chlorination in EWSs. Opportunistic pathogens (OPs) are the dominant infectious agents in EWSs. However, the responses of OPs to a chlorine burn are unknown. This study for the first time assessed how a chlorine burn affected OPs in a full-scale EWS. We determined the impact of a 1.5-month chlorine burn on four dominant OPs (Legionella, Mycobacterium, Pseudomonas, and Vermamoeba vermiformis) in a representative full-scale chloraminated EWS in the United States. Legionella and Mycobacterium were the most abundant OPs. In the water main, the summed concentration of the four OPs during the chlorine burn [3.27 ± 1.58 log10(GCN·L-1); GCN: genome or gene copy number] was lower (p ≤ 0.001) than before the burn [4.83 ± 0.50 log10(GCN·L-1)]. After the burn, the summed concentration increased to 4.27 ± 0.68 log10(GCN·L-1), comparable to before the burn (p > 0.05), indicating a transient effect of the chlorine burn in the water main. At the residential sites, the summed concentrations of the four OPs were comparable (p > 0.05) at 5.50 ± 0.84, 5.27 ± 1.44, and 5.08 ± 0.71 log10(GCN·L-1) before, during, and after the chlorine burn, respectively. Therefore, the chlorine burn was less effective in suppressing OP (re)growth in the premise plumbing. The low effectiveness might be due to more significant water stagnation and disinfectant residual decay in the premise plumbing. Indeed, for the entire sampling period, the total chlorine residual concentration in the premise plumbing (1.8 mg Cl2·L-1) was lower than in the water main (2.4 mg Cl2·L-1). Consequently, for the entire sampling period, the summed concentration of the four OPs in the premise plumbing [5.26 ± 1.08 log10(GCN·L-1)] was significantly higher (p < 0.001) than in the water main [4.04 ± 1.25 log10(GCN·L-1)]. In addition, the chlorine burn substantially increased the levels of disinfection by-products (DBPs) in the water main. Altogether, a chlorine burn is transient or even ineffective in suppressing OP (re)growth but raises DBP concentrations in chloraminated EWSs. Therefore, the practice of chlorine burns to control nitrification should be optimized, reconsidered, or even replaced.
Collapse
Affiliation(s)
- Chiqian Zhang
- Civil Engineering Program, College of Engineering & Computer Science, Arkansas State University, AR 72467, United States
| | - Nathan Sienkiewicz
- Office of Research and Development, United States Environmental Protection Agency, Cincinnati, OH 45268, United States
| | - Ian Struewing
- Office of Research and Development, United States Environmental Protection Agency, Cincinnati, OH 45268, United States
| | - Jatin H Mistry
- United States Environmental Protection Agency, Region 6, Dallas, TX 75270, United States
| | - Helen Buse
- Office of Research and Development, United States Environmental Protection Agency, Cincinnati, OH 45268, United States
| | - Zhiqiang Hu
- Department of Civil & Environmental Engineering, University of Missouri, Columbia, MO 65211, United States
| | - Jingrang Lu
- Office of Research and Development, United States Environmental Protection Agency, Cincinnati, OH 45268, United States.
| |
Collapse
|
2
|
Barbosa A, Azevedo NF, Goeres DM, Cerqueira L. Ecology of Legionella pneumophila biofilms: The link between transcriptional activity and the biphasic cycle. Biofilm 2024; 7:100196. [PMID: 38601816 PMCID: PMC11004079 DOI: 10.1016/j.bioflm.2024.100196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 03/10/2024] [Accepted: 03/29/2024] [Indexed: 04/12/2024] Open
Abstract
There has been considerable discussion regarding the environmental life cycle of Legionella pneumophila and its virulence potential in natural and man-made water systems. On the other hand, the bacterium's morphogenetic mechanisms within host cells (amoeba and macrophages) have been well documented and are linked to its ability to transition from a non-virulent, replicative state to an infectious, transmissive state. Although the morphogenetic mechanisms associated with the formation and detachment of the L. pneumophila biofilm have also been described, the capacity of the bacteria to multiply extracellularly is not generally accepted. However, several studies have shown genetic pathways within the biofilm that resemble intracellular mechanisms. Understanding the functionality of L. pneumophila cells within a biofilm is fundamental for assessing the ecology and evaluating how the biofilm architecture influences L. pneumophila survival and persistence in water systems. This manuscript provides an overview of the biphasic cycle of L. pneumophila and its implications in associated intracellular mechanisms in amoeba. It also examines the molecular pathways and gene regulation involved in L. pneumophila biofilm formation and dissemination. A holistic analysis of the transcriptional activities in L. pneumophila biofilms is provided, combining the information of intracellular mechanisms in a comprehensive outline. Furthermore, this review discusses the techniques that can be used to study the morphogenetic states of the bacteria within biofilms, at the single cell and population levels.
Collapse
Affiliation(s)
- Ana Barbosa
- LEPABE – Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
- ALiCE – Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
| | - Nuno F. Azevedo
- LEPABE – Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
- ALiCE – Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
| | - Darla M. Goeres
- LEPABE – Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
- ALiCE – Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
- The Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| | - Laura Cerqueira
- LEPABE – Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
- ALiCE – Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
| |
Collapse
|
3
|
Zhang Y, Liu M, Wang J, Han K, Han F, Wang B, Xie S, Yuan C, Zhao M, Li S, Wang J. Bibliometric analysis of the association between drinking water pollution and bladder cancer. Front Oncol 2023; 13:1170700. [PMID: 37456244 PMCID: PMC10346845 DOI: 10.3389/fonc.2023.1170700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 06/15/2023] [Indexed: 07/18/2023] Open
Abstract
Background Bladder cancer has become an increasingly intractable health problem worldwide. Long-term drinking water pollution is known to promote its occurrence. This study aimed to analyze the research status, hot spots, and future trends of drinking water pollution and bladder cancer through extensive bibliometric examination to provide reference data for better prevention and management of bladder cancer. Methods The Scopus database developed by Elsevier was browsed for articles that met the predefined criteria using the search terms related to drinking water and bladder cancer. Included articles were further evaluated by year of publication, subject category, institution, article type, source journal, authors, co-authorship networks, and text mining of titles by R software packages tm, ggplot2 and VOSviewer software. Results In total, 687 articles were selected after a comprehensive literature search by the Scopus database, including 491 research articles, 98 review articles, 26 conference papers, 23 letters and 49 other documents. The total number of articles published showed an upward trend. The United States has the largest number of published articles (345 articles), institutions (7/10) and funding sponsors (top 5). The journal with the most publications was Environmental Health Perspectives, with 46 published. The highest number of citations up to 2330 times for a single article published in 2007 on the journal of Mutation Research. Professor Cantor K.P. was the highest number of publications with 35 articles and Smith A.H. was the most cited author with the number of citations reaching 6987 times overall and 225 times per article. The most frequent keywords excluding the search subject were "arsenic", "chlorination", "trihalomethane", and "disease agents". Conclusion This study is the first systematic bibliometric study of the literature publications on drinking water pollution and bladder cancer. It offers an overall and intuitive understanding of this topic in the past few years, and points out a clear direction research hotspots and reveals the trends for further in-depth study in future.
Collapse
Affiliation(s)
- Ying Zhang
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, China
- Center for Single-Cell Omics and Tumor Liquid Biopsy, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Mei Liu
- Department of Laboratory Medicine, Wuhan Hankou Hospital, Wuhan, China
| | - Jiajun Wang
- Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Kexin Han
- Center for Single-Cell Omics and Tumor Liquid Biopsy, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Fuyu Han
- Center for Single-Cell Omics and Tumor Liquid Biopsy, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Bicheng Wang
- Department of Pathology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Si Xie
- Department of Laboratory Medicine, Wuhan Children’s Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chunhui Yuan
- Department of Laboratory Medicine, Wuhan Children’s Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Mingdeng Zhao
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, China
| | - Shuo Li
- Center for Single-Cell Omics and Tumor Liquid Biopsy, Zhongnan Hospital of Wuhan University, Wuhan, China
- Department of Clinical Laboratory, Renmin Hospital of Wuhan University, Wuhan, China
| | - Jun Wang
- Department of Laboratory Medicine, Wuhan Children’s Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| |
Collapse
|
4
|
Nisar MA, Ros KE, Brown MH, Bentham R, Best G, Xi J, Hinds J, Whiley H. Stagnation arising through intermittent usage is associated with increased viable but non culturable Legionella and amoeba hosts in a hospital water system. Front Cell Infect Microbiol 2023; 13:1190631. [PMID: 37351181 PMCID: PMC10282743 DOI: 10.3389/fcimb.2023.1190631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 05/18/2023] [Indexed: 06/24/2023] Open
Abstract
Hospital water systems are a significant source of Legionella, resulting in the potentially fatal Legionnaires' disease. One of the biggest challenges for Legionella management within these systems is that under unfavorable conditions Legionella transforms itself into a viable but non culturable (VBNC) state that cannot be detected using the standard methods. This study used a novel method (flow cytometry-cell sorting and qPCR [VFC+qPCR] assay) concurrently with the standard detection methods to examine the effect of temporary water stagnation, on Legionella spp. and microbial communities present in a hospital water system. Water samples were also analyzed for amoebae using culture and Vermamoeba vermiformis and Acanthamoeba specific qPCR. The water temperature, number and duration of water flow events for the hand basins and showers sampled was measured using the Enware Smart Flow® monitoring system. qPCR analysis demonstrated that 21.8% samples were positive for Legionella spp., 21% for L. pneumophila, 40.9% for V. vermiformis and 4.2% for Acanthamoeba. All samples that were Legionella spp. positive using qPCR (22%) were also positive for VBNC Legionella spp.; however, only 2.5% of samples were positive for culturable Legionella spp. 18.1% of the samples were positive for free-living amoebae (FLA) using culture. All samples positive for Legionella spp. were also positive for FLA. Samples with a high heterotrophic plate count (HPC ≥ 5 × 103 CFU/L) were also significantly associated with high concentrations of Legionella spp. DNA, VBNC Legionella spp./L. pneumophila (p < 0.01) and V. vermiformis (p < 0.05). Temporary water stagnation arising through intermittent usage (< 2 hours of usage per month) significantly (p < 0.01) increased the amount of Legionella spp. DNA, VBNC Legionella spp./L. pneumophila, and V. vermiformis; however, it did not significantly impact the HPC load. In contrast to stagnation, no relationship was observed between the microbes and water temperature. In conclusion, Legionella spp. (DNA and VBNC) was associated with V. vermiformis, heterotrophic bacteria, and stagnation occurring through intermittent usage. This is the first study to monitor VBNC Legionella spp. within a hospital water system. The high percentage of false negative Legionella spp. results provided by the culture method supports the use of either qPCR or VFC+qPCR to monitor Legionella spp. contamination within hospital water systems.
Collapse
Affiliation(s)
- Muhammad Atif Nisar
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
| | - Kirstin E. Ros
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
| | - Melissa H. Brown
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
- Australian Research Council Training Centre for Biofilm Research and Innovation, Flinders University, Bedford Park, SA, Australia
| | - Richard Bentham
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
| | - Giles Best
- College of Medicine and Public Health, Flinders University, Bedford Park, SA, Australia
- Flow Cytometry Facility, Flinders University, Bedford Park, SA, Australia
| | - James Xi
- Enware Australia Pty Ltd., Caringbah, NSW, Australia
| | - Jason Hinds
- Enware Australia Pty Ltd., Caringbah, NSW, Australia
| | - Harriet Whiley
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
- Australian Research Council Training Centre for Biofilm Research and Innovation, Flinders University, Bedford Park, SA, Australia
| |
Collapse
|
5
|
Zhou Q, Huang J, Guo K, Lou Y, Wang H, Zhou R, Tang J, Hou P. Spatiotemporal distribution of opportunistic pathogens and microbial community in centralized rural drinking water: One year survey in China. ENVIRONMENTAL RESEARCH 2023; 218:115045. [PMID: 36513125 DOI: 10.1016/j.envres.2022.115045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 11/18/2022] [Accepted: 12/09/2022] [Indexed: 06/17/2023]
Abstract
Centralized water supply in rural areas, supported by small waterworks (small-central mode) and by municipal water treatment plants (urban-extension mode), is an important guarantee to implement the Rural Revitalization Strategy Plan (2018-2022) in China. Opportunistic pathogens (OPs) could not be evaluated by the national drinking water sanitation standards in China (GB 5749-2022), posing potential microbial risks in rural drinking water. In this study, the spatiotemporal distribution of OPs, microbial community and the associated functional composition under two central water supply modes were investigated by molecular approaches. The results indicated that OPs were widely presented in the rural drinking water regardless of water supply modes, and were more abundant than those in the urban tap water. The insufficient residual chlorine and higher turbidity triggered more microbial proliferation, posing a seasonal variation of OPs gene copy numbers and bacterial community compositions. In warm seasons of summer and autumn, the gene copies of E. coli, M. avium, Pseudomonas spp. and the amoeba host Acanthamoeba spp. achieved up to 4.92, 3.94, 6.75 and 3.74 log10 (gene copies/mL), respectively. Potential functional prediction indicated higher relative abundance of pathogenic genes and infectious risks associated with the rural drinking water under small-central water supply mode. This one-year survey of the spatiotemporal distribution of OPs and microbial community provided scientific insights into microbial safety of rural drinking water, prompting attention on small-central water supply mode against OPs risks.
Collapse
Affiliation(s)
- Qiaomei Zhou
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, PR China.
| | - Jingang Huang
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, PR China; The Belt and Road Information Research Institute, Hangzhou Dianzi University, Hangzhou, 310018, PR China.
| | - Kangyin Guo
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, PR China; Zhejiang Sunrise Garment Group Co., Ltd., Shengzhou, 312400, PR China
| | - Yucheng Lou
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| | - Haibo Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China.
| | - Rongbing Zhou
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| | - Junhong Tang
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| | - Pingzhi Hou
- The Belt and Road Information Research Institute, Hangzhou Dianzi University, Hangzhou, 310018, PR China
| |
Collapse
|
6
|
Zhang C, Struewing I, Mistry JH, Wahman DG, Pressman J, Lu J. Legionella and other opportunistic pathogens in full-scale chloraminated municipal drinking water distribution systems. WATER RESEARCH 2021; 205:117571. [PMID: 34628111 PMCID: PMC8629321 DOI: 10.1016/j.watres.2021.117571] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 08/02/2021] [Accepted: 08/13/2021] [Indexed: 05/06/2023]
Abstract
Water-based opportunistic pathogens (OPs) are a leading cause of drinking-water-related disease outbreaks, especially in developed countries such as the United States (US). Physicochemical water quality parameters, especially disinfectant residuals, control the (re)growth, presence, colonization, and concentrations of OPs in drinking water distribution systems (DWDSs), while the relationship between OPs and those parameters remain unclear. This study aimed to quantify how physicochemical parameters, mainly monochloramine residual concentration, hydraulic residence time (HRT), and seasonality, affected the occurrence and concentrations of four common OPs (Legionella, Mycobacterium, Pseudomonas, and Vermamoeba vermiformis) in four full-scale DWDSs in the US. Legionella as a dominant OP occurred in 93.8% of the 64 sampling events and had a mean density of 4.27 × 105 genome copies per liter. Legionella positively correlated with Mycobacterium, Pseudomonas, and total bacteria. Multiple regression with data from the four DWDSs showed that Legionella had significant correlations with total chlorine residual level, free ammonia concentration, and trihalomethane concentration. Therefore, Legionella is a promising indicator of water-based OPs, reflecting microbial water quality in chloraminated DWDSs. The OP concentrations had strong seasonal variations and peaked in winter and/or spring possibly because of reduced water usage (i.e., increased water stagnation or HRT) during cold seasons. The OP concentrations generally increased with HRT presumably because of disinfectant residual decay, indicating the importance of well-maintaining disinfectant residuals in DWDSs for OP control. The concentrations of Mycobacterium, Pseudomonas, and V. vermiformis were significantly associated with total chlorine residual concentration, free ammonia concentration, and pH and trihalomethane concentration, respectively. Overall, this study demonstrates how the significant spatiotemporal variations of OP concentrations in chloraminated DWDSs correlated with critical physicochemical water quality parameters such as disinfectant residual levels. This work also indicates that Legionella is a promising indicator of OPs and microbial water quality in chloraminated DWDSs.
Collapse
Affiliation(s)
- Chiqian Zhang
- Pegasus Technical Services, Inc., Cincinnati, Ohio, USA
| | - Ian Struewing
- Office of Research and Development, United States Environmental Protection Agency, Cincinnati, Ohio, USA
| | - Jatin H Mistry
- United States Environmental Protection Agency, Region 6, Dallas, Texas, USA
| | - David G Wahman
- Office of Research and Development, United States Environmental Protection Agency, Cincinnati, Ohio, USA
| | - Jonathan Pressman
- Office of Research and Development, United States Environmental Protection Agency, Cincinnati, Ohio, USA
| | - Jingrang Lu
- Office of Research and Development, United States Environmental Protection Agency, Cincinnati, Ohio, USA.
| |
Collapse
|