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Raya S, Malla B, Thakali O, Angga MS, Segawa T, Sherchand JB, Haramoto E. Validation and application of high-throughput quantitative PCR for the simultaneous detection of microbial source tracking markers in environmental water. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 940:173604. [PMID: 38821279 DOI: 10.1016/j.scitotenv.2024.173604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2024] [Revised: 05/24/2024] [Accepted: 05/27/2024] [Indexed: 06/02/2024]
Abstract
No single microbial source tracking (MST) marker can be applied to determine the sources of fecal pollution in all water types. This study aimed to validate a high-throughput quantitative polymerase chain reaction (HT-qPCR) method for the simultaneous detection of multiple MST markers. A total of 26 fecal-source samples that had been previously collected from human sewage (n = 6) and ruminant (n = 3), dog (n = 6), pig (n = 6), chicken (n = 3), and duck (n = 2) feces in the Kathmandu Valley, Nepal, were used to validate 10 host-specific MST markers, i.e., Bacteroidales (BacHum, gyrB, BacR, and Pig2Bac), mitochondrial DNA (mtDNA) (swine, bovine, and Dog-mtDNA), and viral (human adenovirus, porcine adenovirus, and chicken/turkey parvovirus) markers, via HT-qPCR. Only Dog-mtDNA showed 100 % accuracy. All the tested bacterial markers showed a sensitivity of 100 %. Nine of the 10 markers were further used to identify fecal contamination in groundwater sources (n = 54), tanker filling stations (n = 14), drinking water treatment plants (n = 5), and river water samples (n = 6). The human-specific Bacteroidales marker BacHum and ruminant-specific Bacteroidales marker BacR was detected at a high ratio in river water samples (83 % and 100 %, respectively). The results of HT-qPCR were in agreement with the standard qPCR. The comparable performances of HT-qPCR and standard qPCR as well as the successful detection of MST markers in the fecal-source and water samples demonstrated the potential applicability of these markers for detecting fecal contamination sources via HT-qPCR.
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Affiliation(s)
- Sunayana Raya
- Department of Engineering, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511, Japan
| | - Bikash Malla
- Interdisciplinary Center for River Basin Environment, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511, Japan
| | - Ocean Thakali
- Department of Engineering, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511, Japan
| | - Made Sandhyana Angga
- Department of Engineering, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511, Japan
| | - Takahiro Segawa
- Center for Life Science, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi 409-3898, Japan.
| | - Jeevan B Sherchand
- Institute of Medicine, Tribhuvan University, Maharajgunj, Kathmandu 1524, Nepal
| | - Eiji Haramoto
- Interdisciplinary Center for River Basin Environment, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi 400-8511, Japan.
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Tay M, Lee B, Ismail MH, Yam J, Maliki D, Gin KYH, Chae SR, Ho ZJM, Teoh YL, Ng LC, Wong JCC. Usefulness of aircraft and airport wastewater for monitoring multiple pathogens including SARS-CoV-2 variants. J Travel Med 2024; 31:taae074. [PMID: 38813965 DOI: 10.1093/jtm/taae074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 05/17/2024] [Indexed: 05/31/2024]
Abstract
BACKGROUND As global travel resumed in coronavirus disease 2019 (COVID-19) endemicity, the potential of aircraft wastewater monitoring to provide early warning of disease trends for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants and other infectious diseases, particularly at international air travel hubs, was recognized. We therefore assessed and compared the feasibility of testing wastewater from inbound aircraft and airport terminals for 18 pathogens including SARS-CoV-2 in Singapore, a popular travel hub in Asia. METHODS Wastewater samples collected from inbound medium- and long-haul flights and airport terminals were tested for SARS-CoV-2. Next Generation Sequencing was carried out on positive samples to identify SARS-CoV-2 variants. Airport and aircraft samples were further tested for 17 other pathogens through quantitative reverse transcription polymerase chain reaction. RESULTS The proportion of SARS-CoV-2-positive samples and the average virus load was higher for wastewater samples from aircraft as compared with airport terminals. Cross-correlation analyses indicated that viral load trends from airport wastewater led local COVID-19 case trends by 2-5 days. A total of 10 variants (44 sub-lineages) were successfully identified from aircraft wastewater and airport terminals, and four variants of interest and one variant under monitoring were detected in aircraft and airport wastewater 18-31 days prior to detection in local clinical cases. The detection of five respiratory and four enteric viruses in aircraft wastewater samples further underscores the potential to expand aircraft wastewater to monitoring pathogens beyond SARS-CoV-2. CONCLUSION Our findings demonstrate the feasibility of aircraft wastewater testing for monitoring infectious diseases threats, potentially detecting signals before clinical cases are reported. The triangulation of similar datapoints from aircraft wastewater of international travel nodes could therefore serve as a useful early warning system for global health threats.
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Affiliation(s)
- Martin Tay
- Environmental Health Institute, National Environment Agency, Singapore
| | - Benjamin Lee
- Environmental Health Institute, National Environment Agency, Singapore
| | | | - Jerald Yam
- Environmental Health Institute, National Environment Agency, Singapore
| | | | - Karina Yew-Hoong Gin
- NUS Environmental Research Institute, National University of Singapore, Singapore
- Energy and Environmental Sustainability for Megacities (E2S2) Phase II, Campus for Research Excellence and Technological Enterprise (CREATE), Singapore
- Department of Civil & Environmental Engineering, National University of Singapore, Singapore
| | - Sae-Rom Chae
- Communicable Diseases Group, Ministry of Health, Singapore
- National Centre for Infectious Diseases, Singapore
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore
| | | | - Yee Leong Teoh
- Communicable Diseases Group, Ministry of Health, Singapore
- National Centre for Infectious Diseases, Singapore
| | - Lee Ching Ng
- Environmental Health Institute, National Environment Agency, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore
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Molale-Tom LG, Olanrewaju OS, Kritzinger RK, Fri J, Bezuidenhout CC. Heterotrophic bacteria in drinking water: evaluating antibiotic resistance and the presence of virulence genes. Microbiol Spectr 2024; 12:e0335923. [PMID: 38205959 PMCID: PMC10845987 DOI: 10.1128/spectrum.03359-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 12/08/2023] [Indexed: 01/12/2024] Open
Abstract
Heterotrophic bacteria, impacting those with infections or compromised immunity, pose heightened health risks when resistant to antibiotics. This study investigates heterotrophic plate count bacteria in water from North West-C (NWC) and North West-G (NWG) facilities, revealing prevalent β-hemolysis (NWC 82.5%, NWG 86.7%), enzyme production (98%), and antibiotic resistance, especially in NWC. NWG exhibits variations in hemolysin (P = 0.013), lipase (P = 0.009), and DNase activity (P = 0.006). Antibiotics, including ciprofloxacin, persist throughout treatment, with high resistance to β-lactams and trimethoprim (47%-100%), predominantly in NWC. Multiple antibiotic resistance index indicates that 90% of values exceed 0.20, signifying isolates from high antibiotic usage sources. Whole genome sequencing reveals diverse antibiotic resistance genes in heterotrophic strains, emphasizing their prevalence and health risks in water.IMPORTANCEThis study's findings are a stark reminder of a significant health concern: our water sources harbor antibiotic-resistant heterotrophic bacteria, which can potentially cause illness, especially in individuals with weakened immune systems or underlying infections. Antibiotic resistance among these bacteria is deeply concerning, as it threatens the effectiveness of antibiotics, critical for treating various infections. Moreover, detecting virulence factors in a notable proportion of these bacteria highlights their elevated risk to public health. This research underscores the immediate need for enhanced water treatment processes, rigorous water quality monitoring, and the development of strategies to combat antibiotic resistance in the environment. Safeguarding the safety of our drinking water is imperative to protect public health and mitigate the spread of antibiotic-resistant infections, making these findings a compelling call to action for policymakers and public health authorities alike.
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Affiliation(s)
- Lesego G. Molale-Tom
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Oluwaseyi S. Olanrewaju
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Rinaldo K. Kritzinger
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Justine Fri
- Antimicrobial Resistance and Phage Bio-Control Research Laboratory, Department of Microbiology, Faculty of Natural and Agricultural Sciences, North-West University, Mmabatho, South Africa
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Custodio M, Peñaloza R, Ochoa S, De la Cruz H, Rodríguez C, Cuadrado W. Microbial and potentially toxic elements risk assessment in high Andean river water based on Monte Carlo simulation, Peru. Sci Rep 2023; 13:21473. [PMID: 38053001 PMCID: PMC10697974 DOI: 10.1038/s41598-023-48853-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 11/30/2023] [Indexed: 12/07/2023] Open
Abstract
The study evaluated microbial and Potentially Toxic Elements-PTEs risks in high Andean river water in Peru using Monte Carlo simulation. A total of 144 water samples were collected from four rivers and evaluated for physicochemical parameters, PTEs and bacterial pathogens. The microbial risk analysis for exposure to pathogens present in the water was based on the probability of occurrence of diseases associated with Escherichia coli, Pseudomonas aeruginosa and enterococci. PTEs risk analysis was performed using a Monte Carlo simulation approach. The results showed that the highest microbial risk due to exposure to water contaminated by E. coli, P. aeruginosa and enterococci was recorded in the Miraflores and Chia rivers. Meanwhile, the analysis of carcinogenic and non-carcinogenic risk by PTEs in adults and children revealed that the Chia river presents a high risk of contamination by PTEs, especially the carcinogenic risk for children. The Monte Carlo simulation indicated a 56.16% and 94.85% probability of exceeding the limit value of 0.0001 for carcinogenic risk in adults and children, respectively. It can be concluded that children consuming the waters of the Chia river are potentially at risk of As toxicity.
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Affiliation(s)
- María Custodio
- Centro de Investigación en Medicina de Altura y Medio Ambiente, Facultad de Medicina Humana, Universidad Nacional del Centro del Perú, Av. Mariscal Castilla N° 3989-4089, Huancayo, Peru.
| | - Richard Peñaloza
- Centro de Investigación en Medicina de Altura y Medio Ambiente, Facultad de Medicina Humana, Universidad Nacional del Centro del Perú, Av. Mariscal Castilla N° 3989-4089, Huancayo, Peru
| | - Salomé Ochoa
- Centro de Investigación en Medicina de Altura y Medio Ambiente, Facultad de Medicina Humana, Universidad Nacional del Centro del Perú, Av. Mariscal Castilla N° 3989-4089, Huancayo, Peru
| | - Heidi De la Cruz
- Facultad de Ingeniería Química, Universidad Nacional del Centro del Perú, Av. Mariscal Castilla N° 3989-4089, Huancayo, Peru
| | - Ciro Rodríguez
- Centro de Investigación en Medicina de Altura y Medio Ambiente, Facultad de Medicina Humana, Universidad Nacional del Centro del Perú, Av. Mariscal Castilla N° 3989-4089, Huancayo, Peru
| | - Walter Cuadrado
- Universidad Nacional Autónoma Altoandina de Tarma, Jr. Huaraz 431, Tarma, Peru
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Panizzolo M, Gea M, Carraro E, Gilli G, Bonetta S, Pignata C. Occurrence of human pathogenic viruses in drinking water and in its sources: A review. J Environ Sci (China) 2023; 132:145-161. [PMID: 37336605 DOI: 10.1016/j.jes.2022.07.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 07/19/2022] [Accepted: 07/21/2022] [Indexed: 06/21/2023]
Abstract
Since many waterborne diseases are caused by human pathogenic viruses, virus monitoring of drinking water (DW) and DW sources is crucial for public health. Therefore, the aim of this review was to describe the occurrence of human pathogenic viruses in DW and DW sources; the occurrence of two viruses proposed as novel indicators of human faecal contamination (Pepper mild mottle virus and Tobacco mosaic virus) was also reported. This research was focused on articles that assessed viral occurrence using molecular methods in the surface water used for DW production (SW-D), groundwater used for DW production (GW-D), DW and bottled-DW (BW). A total of 1544 studies published in the last 10 years were analysed, and 79 were ultimately included. In considering the detection methods, filtration is the most common concentration technique, while quantitative polymerase chain reaction is the most common quantification technique. Regarding virus occurrence in SW-D, GW-D, and DW, high percentages of positive samples were reported for adenovirus, polyomavirus and Pepper mild mottle virus. Viral genomes were frequently detected in SW-D and rarely in GW-D, suggesting that GW-D may be a safe DW source. Viral genomes were also detected in DW, posing a possible threat to human health. The lowest percentages of positive samples were found in Europe, while the highest were found in Asia and South America. Only three articles assessed viral occurrence in BW. This review highlights the lack of method standardization and the need for legislation updates.
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Affiliation(s)
- Marco Panizzolo
- Department of Public Health and Pediatrics, University of Torino, Piazza Polonia 94, 10126, Torino, Italy
| | - Marta Gea
- Department of Public Health and Pediatrics, University of Torino, Piazza Polonia 94, 10126, Torino, Italy.
| | - Elisabetta Carraro
- Department of Public Health and Pediatrics, University of Torino, Piazza Polonia 94, 10126, Torino, Italy
| | - Giorgio Gilli
- Department of Public Health and Pediatrics, University of Torino, Piazza Polonia 94, 10126, Torino, Italy
| | - Silvia Bonetta
- Department of Life Sciences and Systems Biology, University of Torino, via Accademia Albertina 13, 10123, Torino, Italy
| | - Cristina Pignata
- Department of Public Health and Pediatrics, University of Torino, Piazza Polonia 94, 10126, Torino, Italy
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Goh SG, Haller L, Ng C, Charles FR, Jitxin L, Chen H, He Y, Gin KYH. Assessing the additional health burden of antibiotic resistant Enterobacteriaceae in surface waters through an integrated QMRA and DALY approach. JOURNAL OF HAZARDOUS MATERIALS 2023; 458:132058. [PMID: 37459761 DOI: 10.1016/j.jhazmat.2023.132058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 06/15/2023] [Accepted: 07/12/2023] [Indexed: 07/26/2023]
Abstract
Antibiotic resistant Enterobacteriaceae pose a significant threat to public health. However, limited studies have evaluated the health risks associated with exposure to antibiotic-resistant bacteria (ARB), especially in natural environments. While quantitative microbial risk assessment (QMRA) assesses microbial risks in terms of the probability of infection, it does not account for the severity of health outcomes. In this study, a QMRA-DALY model was developed to integrate QMRA with health burden (disability-adjusted life years (DALY)) from infections caused by ARB. The model considers uncertainties in probability of infection and health burden assessment using Monte Carlo simulations. The study collected antimicrobial resistance (AMR) surveillance data from surface waters with different land uses. Results revealed water bodies with agricultural land use to be the main AMR hotspots, with the highest additional health burden observed in infections caused by meropenem-resistant E. coli (∆DALY = 0.0105 DALY/event) compared to antibiotic-susceptible E. coli. The estimated ∆DALY for antibiotic-resistant K. pneumoniae was lower than for antibiotic-resistant E. coli (highest ∆DALY = 0.00048 DALY/event). The study highlights the need for better evaluation of AMR associated health burden, and effective measures to mitigate the risks associated with antibiotic-resistant bacteria in natural environments.
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Affiliation(s)
- Shin Giek Goh
- NUS Environmental Research Institute, National University of Singapore, Singapore 117411, Singapore
| | - Laurence Haller
- NUS Environmental Research Institute, National University of Singapore, Singapore 117411, Singapore
| | - Charmaine Ng
- NUS Environmental Research Institute, National University of Singapore, Singapore 117411, Singapore
| | - Francis Rathinam Charles
- NUS Environmental Research Institute, National University of Singapore, Singapore 117411, Singapore
| | - Lim Jitxin
- NUS Environmental Research Institute, National University of Singapore, Singapore 117411, Singapore
| | - Hongjie Chen
- NUS Environmental Research Institute, National University of Singapore, Singapore 117411, Singapore
| | - Yiliang He
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Karina Yew-Hoong Gin
- NUS Environmental Research Institute, National University of Singapore, Singapore 117411, Singapore; Department of Civil & Environmental Engineering, National University of Singapore, Singapore 117576, Singapore.
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Alegbeleye O, Sant'Ana AS. Microbiological quality of irrigation water for cultivation of fruits and vegetables: An overview of available guidelines, water testing strategies and some factors that influence compliance. ENVIRONMENTAL RESEARCH 2023; 220:114771. [PMID: 36586712 DOI: 10.1016/j.envres.2022.114771] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 11/06/2022] [Accepted: 11/07/2022] [Indexed: 06/17/2023]
Abstract
Contaminated irrigation water is among many potential vehicles of human pathogens to food plants, constituting significant public health risks especially for the fresh produce category. This review discusses some available guidelines or regulations for microbiological safety of irrigation water, and provides a summary of some common methods used for characterizing microbial contamination. The goal of such exploration is to understand some of the considerations that influence formulation of water testing guidelines, describe priority microbial parameters particularly with respect to food safety risks, and attempt to determine what methods are most suitable for their screening. Furthermore, the review discusses factors that influence the potential for microbiologically polluted irrigation water to pose substantial risks of pathogenic contamination to produce items. Some of these factors include type of water source exploited, irrigation methods, other agro ecosystem features/practices, as well as pathogen traits such as die-off rates. Additionally, the review examines factors such as food safety knowledge, other farmer attitudes or inclinations, level of social exposure and financial circumstances that influence adherence to water testing guidelines and other safe water application practices. A thorough understanding of relevant risk metrics for the application and management of irrigation water is necessary for the development of water testing criteria. To determine sampling and analytical approach for water testing, factors such as agricultural practices (which differ among farms and regionally), as well as environmental factors that modulate how water quality may affect the microbiological safety of produce should be considered. Research and technological advancements that can improve testing approach and the determination of target levels for hazard characterization or description for the many different pollution contexts as well as farmer adherence to testing requirements, are desirable.
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Affiliation(s)
- Oluwadara Alegbeleye
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil
| | - Anderson S Sant'Ana
- Department of Food Science and Nutrition, Faculty of Food Engineering, University of Campinas, Campinas, SP, Brazil.
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CrAssphage May Be Viable Markers of Contamination in Pristine and Contaminated River Water. mSystems 2023; 8:e0128222. [PMID: 36744944 PMCID: PMC9948693 DOI: 10.1128/msystems.01282-22] [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] [Indexed: 02/07/2023] Open
Abstract
Viruses are the most biologically abundant entities and may be ideal indicators of fecal pollutants in water. Anthropogenic activities have triggered drastic ecosystem changes in rivers, leading to substantial shifts in chemical and biological attributes. Here, we evaluate the viability of using the presence of crAssphage as indicators of fecal contamination in South African rivers. Shotgun analysis revealed diverse crAssphage viruses in these rivers, which are impacted by chemical and biological pollution. Overall, the diversity and relative abundances of these viruses was higher in contaminated sites compared to pristine locations. In contrast to fecal coliform counts, crAssphage sequences were detected in pristine rivers, supporting the assertion that the afore mentioned marker may be a more accurate indicator of fecal contamination. Our data demonstrate the presence of diverse putative hosts which includes members of the phyla Bacteroidota, Pseudomonadota, Verrucomicrobiota, and Bacillota. Phylogenetic analysis revealed novel subfamilies, suggesting that rivers potentially harbor distinct and uncharacterized clades of crAssphage. These data provide the first insights regarding the diversity, distribution, and functional roles of crAssphage in rivers. Taken together, the results support the potential application of crAssphage as viable markers for water quality monitoring. IMPORTANCE Rivers support substantial populations and provide important ecosystem services. Despite the application of fecal coliform tests and other markers, we lack rapid and reproducible approaches for determining fecal contamination in rivers. Waterborne viral outbreaks have been reported even after fecal indicator bacteria (FIB) were suggested to be absent or below regulated levels of coliforms. This indicates a need to develop and apply improved indicators of pollutants in aquatic ecosystems. Here, we evaluate the viability of crAssphage as indicators of fecal contamination in two South African rivers. We assess the abundance, distribution, and diversity of these viruses in sites that had been predicted pristine or contaminated by FIB analysis. We show that crAssphage are ideal and sensitive markers for fecal contamination and describe novel clades of crAss-like phages. Known crAss-like subfamilies were unrepresented in our data, suggesting that the diversity of these viruses may reflect geographic locality and dependence.
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Lv B, Zhu G, Tian W, Guo C, Lu X, Han Y, An T, Cui Y, Jiang T. The prevalence of potential pathogens in ballast water and sediments of oceangoing vessels and implications for management. ENVIRONMENTAL RESEARCH 2023; 218:114990. [PMID: 36463990 DOI: 10.1016/j.envres.2022.114990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 11/26/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
Ballast water and sediments can serve as prominent vectors for the widespread dispersal of pathogens between geographically distant areas. However, information regarding the diversity and distribution of the bacterial pathogens in ballast water and sediments is highly limited. In this study, using high-throughput sequencing and quantitative PCR, we investigated the composition and abundance of potential pathogens, and their associations with indicator microorganisms. We accordingly detected 48 potential bacterial pathogens in the assessed ballast water and sediments, among which there were significant differences in the compositions and abundances of pathogenic bacterial communities characterizing ballast water and sediments. Rhodococcus erythropolis, Bacteroides vulgatus, and Vibrio campbellii were identified as predominant pathogens in ballast water, whereas Pseudomonas stutzeri, Mycobacterium paragordonae, and Bacillus anthracis predominated in ballast sediments. Bacteroidetes, Vibrio alginolyticus, Vibrio parahaemolyticus, and Escherichia coli were generally detected with median values of 8.54 × 103-1.22 × 107 gene copies (GC)/100 mL and 1.16 × 107-3.97 × 109 GC/100 g in ballast water and sediments, respectively. Notably, the concentrations of Shigella sp., Staphylococcus aureus, and V. alginolyticus were significantly higher in ballast sediments than in the water. In addition, our findings tend to confirm that the indicator species specified by the International Maritime Organization (IMO) might underestimate the pathogen risk in the ballast water and sediments, as these bacteria were unable to predict some potential pathogens assessed in this study. In summary, this study provides a comprehensive insight into the spectrum of the potential pathogens that transferred by ship ballast tanks and emphasizes the need for the implementation of IMO convention on ballast sediment management.
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Affiliation(s)
- Baoyi Lv
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai, 201306, China.
| | - Guorong Zhu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai, 201306, China
| | - Wen Tian
- Jiangyin Customs, Jiangyin, 214400, China
| | - Chong Guo
- Maritime Safety Bureau of Yangshan Port, Shanghai, 201306, China
| | - Xiaolan Lu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai, 201306, China
| | - Yangchun Han
- Maritime Safety Bureau of Yangshan Port, Shanghai, 201306, China
| | - Tingxuan An
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai, 201306, China
| | - Yuxue Cui
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecology and Environmental Sciences, East China Normal University, Shanghai, 200241, China
| | - Ting Jiang
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai, 201306, China
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Suzuki Y, Shimizu H, Tamai S, Hoshiko Y, Maeda T, Nukazawa K, Iguchi A, Masago Y, Ishii S. Simultaneous detection of various pathogenic Escherichia coli in water by sequencing multiplex PCR amplicons. ENVIRONMENTAL MONITORING AND ASSESSMENT 2023; 195:264. [PMID: 36600083 DOI: 10.1007/s10661-022-10863-6] [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: 10/05/2022] [Accepted: 12/19/2022] [Indexed: 06/17/2023]
Abstract
Waterborne diseases due to pathogen contamination in water are a serious problem all over the world. Accurate and simultaneous detection of pathogens in water is important to protect public health. In this study, we developed a method to simultaneously detect various pathogenic Escherichia coli by sequencing the amplicons of multiplex PCR. Our newly designed multiplex PCR amplified five genes for pathogenic E. coli (uidA, stx1, stx2, STh gene, and LT gene). Additional two PCR assays (for aggR and eae) were also designed and included in the amplicon sequencing analysis. The same assays were also used for digital PCR (dPCR). Strong positive correlations were observed between the sequence read count and the dPCR results for most of the genes targeted, suggesting that our multiplex PCR-amplicon sequencing approach could provide quantitative information. The method was also successfully applied to monitor the level of pathogenic E. coli in river water and wastewater samples. The approach shown here could be expanded by targeting genes for other pathogens.
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Affiliation(s)
- Yoshihiro Suzuki
- Department of Civil and Environmental Engineering, Faculty of Engineering, University of Miyazaki, Miyazaki, Japan.
| | - Hiroki Shimizu
- Department of Civil and Environmental Engineering, Faculty of Engineering, University of Miyazaki, Miyazaki, Japan
| | - Shouichiro Tamai
- Department of Civil and Environmental Engineering, Faculty of Engineering, University of Miyazaki, Miyazaki, Japan
| | - Yuki Hoshiko
- Department of Biological Functions Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyushu, 808-0196, Japan
- Present address: Division of Microbiology, Department of Infectious Medicine, Kurume University School of Medicine, 67 Asahi-Machi, Kurume-City, Fukuoka, 830-0011, Japan
| | - Toshinari Maeda
- Department of Biological Functions Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyushu, 808-0196, Japan
| | - Kei Nukazawa
- Department of Civil and Environmental Engineering, Faculty of Engineering, University of Miyazaki, Miyazaki, Japan
| | - Atsushi Iguchi
- Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan
| | - Yoshifumi Masago
- Center for Climate Change Adaptation, National Institute for Environmental Studies, Ibaraki, Japan
| | - Satoshi Ishii
- Department of Soil, Water, and Climate, University of Minnesota, Falcon Heights, MN, USA
- Bio Technology Institute, University of Minnesota, Falcon Heights, MN, USA
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Gu X, Yang Y, Mao F, Lee WL, Armas F, You F, Needham DM, Ng C, Chen H, Chandra F, Gin KY. A comparative study of flow cytometry-sorted communities and shotgun viral metagenomics in a Singapore municipal wastewater treatment plant. IMETA 2022; 1:e39. [PMID: 38868719 PMCID: PMC10989988 DOI: 10.1002/imt2.39] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 04/30/2022] [Accepted: 06/19/2022] [Indexed: 06/14/2024]
Abstract
Traditional or "bulk" viral enrichment and amplification methods used in viral metagenomics introduce unavoidable bias in viral diversity. This bias is due to shortcomings in existing viral enrichment methods and overshadowing by the more abundant viral populations. To reduce the complexity and improve the resolution of viral diversity, we developed a strategy coupling fluorescence-activated cell sorting (FACS) with random amplification and compared this to bulk metagenomics. This strategy was validated on both influent and effluent samples from a municipal wastewater treatment plant using the Modified Ludzack-Ettinger (MLE) process as the treatment method. We found that DNA and RNA communities generated using bulk samples were mostly different from those derived following FACS for both treatments before and after MLE. Before MLE treatment, FACS identified five viral families and 512 viral annotated contigs. Up to 43% of mapped reads were not detected in bulk samples. Nucleo-cytoplasmic large DNA viral families were enriched to a greater extent in the FACS-coupled subpopulations compared with bulk samples. FACS-coupled viromes captured a single-contig viral genome associated with Anabaena phage, which was not observed in bulk samples or in FACS-sorted samples after MLE. These short metagenomic reads, which were assembled into a high-quality draft genome of 46 kbp, were found to be highly dominant in one of the pre-MLE FACS annotated virome fractions (57.4%). Using bulk metagenomics, we identified that between Primary Settling Tank and Secondary Settling Tank viromes, Virgaviridae, Astroviridae, Parvoviridae, Picobirnaviridae, Nodaviridae, and Iridoviridae were susceptible to MLE treatment. In all, bulk and FACS-coupled metagenomics are complementary approaches that enable a more thorough understanding of the community structure of DNA and RNA viruses in complex environmental samples, of which the latter is critical for increasing the sensitivity of detection of viral signatures that would otherwise be lost through bulk viral metagenomics.
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Affiliation(s)
- Xiaoqiong Gu
- Department of Civil and Environmental EngineeringNational University of SingaporeSingaporeSingapore
- Antimicrobial Resistance Interdisciplinary Research GroupSingapore‐MIT Alliance for Research and TechnologySingaporeSingapore
| | - Yi Yang
- NUS Environmental Research InstituteNational University of SingaporeSingaporeSingapore
| | - Feijian Mao
- Department of Civil and Environmental EngineeringNational University of SingaporeSingaporeSingapore
| | - Wei Lin Lee
- Antimicrobial Resistance Interdisciplinary Research GroupSingapore‐MIT Alliance for Research and TechnologySingaporeSingapore
| | - Federica Armas
- Antimicrobial Resistance Interdisciplinary Research GroupSingapore‐MIT Alliance for Research and TechnologySingaporeSingapore
| | - Fang You
- Department of Civil and Environmental EngineeringNational University of SingaporeSingaporeSingapore
| | - David M. Needham
- Monterey Bay Aquarium Research InstituteMoss LandingCaliforniaUSA
- GEOMAR Helmholtz Centre for Ocean ResearchOcean EcoSystems Biology UnitKielGermany
- Department of Biological EngineeringMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
| | - Charmaine Ng
- Department of Civil and Environmental EngineeringNational University of SingaporeSingaporeSingapore
| | - Hongjie Chen
- Department of Civil and Environmental EngineeringNational University of SingaporeSingaporeSingapore
- Antimicrobial Resistance Interdisciplinary Research GroupSingapore‐MIT Alliance for Research and TechnologySingaporeSingapore
| | - Franciscus Chandra
- Department of Civil and Environmental EngineeringNational University of SingaporeSingaporeSingapore
| | - Karina Yew‐Hoong Gin
- Department of Civil and Environmental EngineeringNational University of SingaporeSingaporeSingapore
- NUS Environmental Research InstituteNational University of SingaporeSingaporeSingapore
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12
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Lanrewaju AA, Enitan-Folami AM, Sabiu S, Edokpayi JN, Swalaha FM. Global public health implications of human exposure to viral contaminated water. Front Microbiol 2022; 13:981896. [PMID: 36110296 PMCID: PMC9468673 DOI: 10.3389/fmicb.2022.981896] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 08/05/2022] [Indexed: 01/08/2023] Open
Abstract
Enteric viruses are common waterborne pathogens found in environmental water bodies contaminated with either raw or partially treated sewage discharge. Examples of these viruses include adenovirus, rotavirus, noroviruses, and other caliciviruses and enteroviruses like coxsackievirus and polioviruses. They have been linked with gastroenteritis, while some enteric viruses have also been implicated in more severe infections such as encephalitis, meningitis, hepatitis (hepatitis A and E viruses), cancer (polyomavirus), and myocarditis (enteroviruses). Therefore, this review presents information on the occurrence of enteric viruses of public health importance, diseases associated with human exposure to enteric viruses, assessment of their presence in contaminated water, and their removal in water and wastewater sources. In order to prevent illnesses associated with human exposure to viral contaminated water, we suggest the regular viral monitoring of treated wastewater before discharging it into the environment. Furthermore, we highlight the need for more research to focus on the development of more holistic disinfection methods that will inactivate waterborne viruses in municipal wastewater discharges, as this is highly needed to curtail the public health effects of human exposure to contaminated water. Moreover, such a method must be devoid of disinfection by-products that have mutagenic and carcinogenic potential.
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Affiliation(s)
| | - Abimbola Motunrayo Enitan-Folami
- Department of Biotechnology and Food Science, Durban University of Technology, Durban, South Africa
- *Correspondence: Abimbola Motunrayo Enitan-Folami,
| | - Saheed Sabiu
- Department of Biotechnology and Food Science, Durban University of Technology, Durban, South Africa
| | - Joshua Nosa Edokpayi
- Water and Environmental Management Research Group, Engineering and Agriculture, University of Venda, Thohoyandou, South Africa
| | - Feroz Mahomed Swalaha
- Department of Biotechnology and Food Science, Durban University of Technology, Durban, South Africa
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13
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Goh SG, Jiang P, Ng C, Le TH, Haller L, Chen H, Charles FR, Chen H, Liu X, He Y, Gin KYH. A new modelling framework for assessing the relative burden of antimicrobial resistance in aquatic environments. JOURNAL OF HAZARDOUS MATERIALS 2022; 424:127621. [PMID: 34763923 DOI: 10.1016/j.jhazmat.2021.127621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 09/30/2021] [Accepted: 10/25/2021] [Indexed: 06/13/2023]
Abstract
The infections caused by antibiotic resistant bacteria (ARB) can lead to higher medical costs, prolonged hospital stays, and increased mortality compared to bacteria that are susceptible to antibiotics. Challenges exist in quantifying the potential risk/burden associated with antimicrobial resistance (AMR) as there is a lack of dose-response models available for pathogens which are resistant to antibiotics, in addition to the fact that very little is known regarding the health risks posed by antibiotic resistant genes (ARG). In this paper, we proposed a new modelling framework to evaluate the relative burden of AMR in natural aquatic environments. With this framework, an AMR burden score for each sample was calculated based on burden coefficients assigned for each ARB and ARG, as well as weighted burdens for the separate ARBs and ARGs components. The method developed in this study was applied to assess the relative burden of AMR in local aquatic environments with different land uses at different seasons. The collected filed data were used to verify the applicability of the proposed relative burden assessment method. Through the established method, the spatial and temporal hotspots of AMR were identified, which could provide useful information to agencies for better control and management of AMR emergence in natural aquatic environments.
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Affiliation(s)
- Shin Giek Goh
- NUS Environmental Research Institute, National University of Singapore, 117411, Singapore
| | - Peng Jiang
- Department of Industrial Engineering and Engineering Management, Business School, Sichuan University, Chengdu 610064, China; Department of Industrial Engineering & Management, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Charmaine Ng
- NUS Environmental Research Institute, National University of Singapore, 117411, Singapore
| | - Thai-Hoang Le
- NUS Environmental Research Institute, National University of Singapore, 117411, Singapore
| | - Laurence Haller
- NUS Environmental Research Institute, National University of Singapore, 117411, Singapore
| | - Hongjie Chen
- NUS Environmental Research Institute, National University of Singapore, 117411, Singapore
| | | | - Huiting Chen
- NUS Environmental Research Institute, National University of Singapore, 117411, Singapore
| | - Xiao Liu
- Department of Industrial Engineering & Management, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yiliang He
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Karina Yew-Hoong Gin
- NUS Environmental Research Institute, National University of Singapore, 117411, Singapore; Department of Civil & Environmental Engineering, National University of Singapore, 117576, Singapore.
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14
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Goh SG, Liang L, Gin KYH. Assessment of Human Health Risks in Tropical Environmental Waters with Microbial Source Tracking Markers. WATER RESEARCH 2021; 207:117748. [PMID: 34837748 DOI: 10.1016/j.watres.2021.117748] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 10/06/2021] [Accepted: 10/07/2021] [Indexed: 06/13/2023]
Abstract
Human specific microbial source tracking (MST) markers which are highly specific to human waste contamination offer the advantage of better association with human pathogens than traditional microbial indicators. However, the performance of these MST markers may vary across different geographical regions. The magnitude of MST markers also plays an important role in interpreting the health risks. This study aims to (i) validate the specificity and sensitivity of human markers for tropical urban catchments; (ii) identify the threshold concentrations of MST markers, i.e. human polyomaviruses (HPyVs), Bacteroides thetaiotaomicron (B. theta) and Methanobrevibacter smithii (M. smithii), that correspond to the acceptable gastrointestinal (GI) illness risks associated with swimming using the QMRA approach; and (iii) validate the threshold concentrations of MST markers using the surveillance data obtained from the tropical urban environment. Among the three MST markers, HPyVs showed the highest specificity (100%) to sewage samples, followed by M. smithii (97%) and B. theta (90%). All MST markers showed 100% sensitivity towards sewage contamination, with B. theta present in highest abundance in sewage, followed by HPyVs and M. smithii. This study demonstrates a risk-based framework to identify the threshold concentrations of MST markers associated with GI illness risks in environmental waters by considering two main influencing factors (i.e. decay and dilution factors). This study successfully validated the B. theta threshold concentration range (581 to 8073 GC/100 mL) with field data (370 to 6500 GC/100 mL) in estimating GI illness risks with an Enterococcus model. Field data showed that the MST markers at threshold concentrations were able to classify the safe level in more than 83% of the samples, according to GI illness risks from Enterococcus and adenovirus. The study also highlighted the lack of associations between MST markers and GI illness risks from norovirus. With comprehensive information on specificity, sensitivity and threshold concentrations of MST markers, increasing confidence can be placed on identifying human source contamination and evaluating the health risks posed in environmental waters in Singapore.
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Affiliation(s)
- S G Goh
- NUS Environmental Research Institute, National University of Singapore, T-Lab Building, #02-01, 5A Engineering Drive 1 117411, Singapore
| | - L Liang
- Department of Civil & Environmental Engineering, Faculty of Engineering, National University of Singapore, Block E1A, #07-03,1 Engineering Drive 2 117576, Singapore
| | - K Y H Gin
- NUS Environmental Research Institute, National University of Singapore, T-Lab Building, #02-01, 5A Engineering Drive 1 117411, Singapore; Department of Civil & Environmental Engineering, Faculty of Engineering, National University of Singapore, Block E1A, #07-03,1 Engineering Drive 2 117576, Singapore.
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15
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Boufafa M, Kadri S, Redder P, Bensouilah M. Occurrence and distribution of fecal indicators and pathogenic bacteria in seawater and Perna perna mussel in the Gulf of Annaba (Southern Mediterranean). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:46035-46052. [PMID: 33884549 DOI: 10.1007/s11356-021-13978-4] [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: 10/06/2020] [Accepted: 04/13/2021] [Indexed: 06/12/2023]
Abstract
The identification of fecal contamination in coastal marine ecosystems is one of the main requirements for evaluation of potential risks to human health. The objective of this study was to investigate the occurrence and distribution of fecal indicators and pathogenic bacteria in seawaters and mussels collected monthly during a period of 1 year from four different sites in Northeastern Algeria (sites S1 to S4), through biochemical and molecular analyses. Our research is the first to use molecular analysis to unambiguously identify the potentially pathogenic bacteria present in Algerian Perna perna mussels. The obtained results revealed that the levels of fecal indicator bacteria (FIB) from both P. perna and seawater samples largely exceeded the permissible limits at S2 and S3. This is mainly related to their location close to industrial and coastal activity zones, which contain a mixture of urban, agricultural, and industrial pollutants. Besides, P. perna collected from all sites were severalfold more contaminated by FIB than seawater samples, primarily during the warm season of the study period. Biochemical and molecular analyses showed that isolated bacteria from both seawater and mussels were mainly potentially pathogenic species such as E. coli, Salmonella spp., Staphylococcus spp., Klebsiella spp., Pseudomonas spp., and Proteus spp.
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Affiliation(s)
- Mouna Boufafa
- Laboratory of Eco-biology for Marine Environment and Coastlines, Faculty of Science, Badji Moukhtar University, BP 12, 23000, Annaba, Algeria.
| | - Skander Kadri
- Laboratory of Eco-biology for Marine Environment and Coastlines, Faculty of Science, Badji Moukhtar University, BP 12, 23000, Annaba, Algeria
| | - Peter Redder
- Laboratoire de Microbiologie et Génétique Moléculaires, Centre de Biologie Intégrative, Université Paul Sabatier, 118 Route de Narbonne, 31062, Toulouse, France.
| | - Mourad Bensouilah
- Laboratory of Eco-biology for Marine Environment and Coastlines, Faculty of Science, Badji Moukhtar University, BP 12, 23000, Annaba, Algeria
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16
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Shi D, Ma H, Miao J, Liu W, Yang D, Qiu Z, Shen Z, Yin J, Yang Z, Wang H, Li H, Chen Z, Li J, Jin M. Levels of human Rotaviruses and Noroviruses GII in urban rivers running through the city mirror their infection prevalence in populations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 754:142203. [PMID: 32920413 PMCID: PMC7470703 DOI: 10.1016/j.scitotenv.2020.142203] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/02/2020] [Accepted: 09/02/2020] [Indexed: 06/11/2023]
Abstract
Enteric viruses exposed to water pose a huge threat to global public health and can lead to waterborne disease outbreaks. A sudden increase in enteric viruses in some water matrices also underpins the prevalence of corresponding waterborne diseases in communities over the same time period. However, few efforts have been focused on water matrices whose viral pollution may best reflect the clinical prevalence in communities. Here, a one-year surveillance of human enteric viruses including Enteroviruses (EnVs), Rotaviruses (HRVs), Astroviruses (AstVs), Noroviruses GII (HuNoVsGII) and Mastadenoviruses (HAdVs) in four representative water matrices: an urban river (UR) running through city, effluent from Wastewater Treatment Plant (EW), raw water for Urban Water Treatment Plant (RW), and tap water (TW) were performed by qPCR. The relationship between the virus detection frequency at each site and their prevalence in clinical PCR assay was further analyzed. We found that the detection frequencies of HRVs, HuNoVsGII, and AstVs in stools peaked in winter, while EnVs peaked in autumn. No EnVs occurred in EW, RW, or TW, but HuNoVsGII and AstVs occurred intensively in winter. For UR, all types of enteric viruses could be detected and the levels of acute gastroenteritis viruses (HRVs, HuNoVsGII, AstVs, and HAdVs) were highest in autumn or winter, whereas EnVs peaked in summer. In terms of correlation analyses, only HRVs and HuNoVsGII levels in UR showed a strong positive correlation with their prevalence in clinical stool samples. This study indicated that HRVs and HuNoVsGII levels in URs may mirror the local virus prevalence, thereby implying the possibility of revealing their local epidemiology by monitoring them in the URs.
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Affiliation(s)
- Danyang Shi
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, No.1, Dali Road, Tianjin 300050, China
| | - Hui Ma
- Department of Clinical Laboratory, Tianjin Children's Hospital, No. 238, Longyan Road, Tianjin 300134, China
| | - Jing Miao
- Department of Public Health, Shanxi University of Chinese Medicine, Xianyang 712046, China
| | - Weili Liu
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, No.1, Dali Road, Tianjin 300050, China
| | - Dong Yang
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, No.1, Dali Road, Tianjin 300050, China
| | - Zhigang Qiu
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, No.1, Dali Road, Tianjin 300050, China
| | - Zhiqiang Shen
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, No.1, Dali Road, Tianjin 300050, China
| | - Jing Yin
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, No.1, Dali Road, Tianjin 300050, China
| | - Zhongwei Yang
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, No.1, Dali Road, Tianjin 300050, China
| | - Huaran Wang
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, No.1, Dali Road, Tianjin 300050, China
| | - Haibei Li
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, No.1, Dali Road, Tianjin 300050, China
| | - Zhengshan Chen
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, No.1, Dali Road, Tianjin 300050, China
| | - Junwen Li
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, No.1, Dali Road, Tianjin 300050, China.
| | - Min Jin
- Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin Institute of Environmental & Operational Medicine, No.1, Dali Road, Tianjin 300050, China.
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17
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Ahmed W, Toze S, Veal C, Fisher P, Zhang Q, Zhu Z, Staley C, Sadowsky MJ. Comparative decay of culturable faecal indicator bacteria, microbial source tracking marker genes, and enteric pathogens in laboratory microcosms that mimic a sub-tropical environment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 751:141475. [PMID: 32890804 DOI: 10.1016/j.scitotenv.2020.141475] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 08/02/2020] [Accepted: 08/02/2020] [Indexed: 06/11/2023]
Abstract
Enteric pathogens can be present in drinking water catchments due to several point and non-point sources of faecal contamination. Pathogen and contaminant signatures will decay due to environmental stresses, such as temperature, Ultra Violet (UV) radiation, salinity, and predation. In this study, we determined the decay of the culturable faecal indicator bacterium (FIB) Escherichia coli (E. coli), two sewage-associated marker genes (Bacteroides HF183 and crAssphage CPQ_056), and enteric pathogens (Campylobacter spp., human adenovirus 40/41, and Cryptosporidium parvum) in two freshwater laboratory microcosms using culture-based, quantitative PCR (qPCR) and vital dye (determine the fraction of viable Cryptosporidium oocysts) assays. Freshwater samples from the Lake Wappa and Lake Wivenhoe (Australia) were seeded with untreated sewage and C. parvum oocysts, and their declining concentrations were measured over a 28-day period. Moreover, 16S rRNA amplicon sequencing was also undertaken to determine the change/shift in sewage-associated bacterial communities using SourceTracker. Overall, culturable E. coli and the HF183 marker gene decayed significantly (p < 0.05) faster than did the qPCR measured enteric pathogens suggesting that the absence of culturable FIB or qPCR HF183 in water samples may not indicate the absence of pathogens. The decay of crAssphage was similar to that of HAdV 40/41 and other pathogens tested, suggesting crAssphage may be a better surrogate for enteric viruses in sub-tropical catchment waters. The decay rates were greater at 25 °C compared to 15 °C, suggesting that FIB and pathogens persist longer in the winter season compared to summer. Overall decay rates of the tested microorganisms in this microcosm study suggest that sub-tropical conditions, especially temperature, have a negative impact on the persistence of tested microorganisms. Sewage-associated bacterial communities also showed similar patterns. Based on the results, which showed differences in simulated summer and winter temperatures for pathogen decay, corresponding management options and treatment need to be adjusted accordingly to minimize human health risks effectively.
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Affiliation(s)
- Warish Ahmed
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, QLD, Australia.
| | - Simon Toze
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, QLD, Australia
| | - Cameron Veal
- Seqwater, 117 Brisbane Street, Ipswich, QLD, Australia
| | - Paul Fisher
- Seqwater, 117 Brisbane Street, Ipswich, QLD, Australia
| | - Qian Zhang
- Department of Soil, Water, and Climate, and the BioTechnology Institute, University of Minnesota, St. Paul, MN 55108, USA
| | - Zhigang Zhu
- Department of Surgery, University of Minnesota, MN 55455, USA
| | | | - Michael J Sadowsky
- Department of Soil, Water, and Climate, and the BioTechnology Institute, University of Minnesota, St. Paul, MN 55108, USA
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18
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Jacquin C, Yu D, Sander M, Domagala KW, Traber J, Morgenroth E, Julian TR. Competitive co-adsorption of bacteriophage MS2 and natural organic matter onto multiwalled carbon nanotubes. WATER RESEARCH X 2020; 9:100058. [PMID: 32613183 PMCID: PMC7322093 DOI: 10.1016/j.wroa.2020.100058] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 06/05/2020] [Accepted: 06/06/2020] [Indexed: 05/04/2023]
Abstract
A leading challenge in drinking water treatment is to remove small-sized viruses from the water in a simple and efficient manner. Multi-walled carbon nanotubes (MWCNT) are new generation adsorbents with previously demonstrated potential as filter media to improve virus removal. This study therefore aimed to evaluate the field applicability of MWCNT-filters for virus removal in water containing natural organic matter (NOM) as co-solute to viruses, using batch equilibrium experiments. Contrary to previous studies, our results showed with MS2 bacteriophages single-solute systems that the affinity of MWCNT for MS2 was low, since after 3 h of equilibration only 4 log10 reduction value (LRV) of MS2 (20 mL at an initial concentration of 106 PFU MS2/mL) were reached. Single solute experiments with Suwannee river NOM (SRNOM) performed with environmentally-relevant concentrations showed MWCNT surface saturation at initial SRNOM concentrations between 10 and 15 mgC/L, for water pH between 5.2 and 8.7. These results suggested that at NOM:virus ratios found in natural waters, the NOM would competitively suppress virus adsorption onto MWCNT, even at low NOM concentrations. We confirmed this expectation with SRNOM-MS2 co-solute experiments, which showed an exponential decrease of the MS2 LRV by MWCNT with an increase in the initial SRNOM concentration. More interestingly, we showed that pre-equilibrating MWCNT with a SRNOM solution at a concentration as low as 0.4 mgC/L resulted in a LRV decrease of 3 for MS2, due to the formation of a negatively charged SRNOM adlayer on the MWCNT surface. Complementary batch experiments with natural NOM-containing waters and competition experiments with SRNOM in the presence of CaCl2 confirmed that the presence of NOM in waters challenges virus removal by MWCNT-filters, irrespective of the concentration and type of NOM and also in the presence of Ca2+. We therefore conclude that MWCNT-filters produced with commercially available pristine MWCNT cannot be considered as a viable technology for drinking water virus removal.
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Affiliation(s)
- Céline Jacquin
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600, Dübendorf, Switzerland
- Corresponding author.
| | - Diya Yu
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600, Dübendorf, Switzerland
| | - Michael Sander
- Institute of Biogeochemistry and Pollutant Dynamics (IBP), Department of Environmental Systems Science, ETH Zürich, 8092, Zürich, Switzerland
| | - Kamila W. Domagala
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for High Performance Ceramics, Überlandstrasse 129, 8600, Dübendorf, Switzerland
- AGH, University of Science and Technology, Faculty of Materials Science and Ceramics, al. Mickiewicza 30, 30-059, Krakow, Poland
| | - Jacqueline Traber
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600, Dübendorf, Switzerland
| | - Eberhard Morgenroth
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600, Dübendorf, Switzerland
- ETH Zürich, Institute of Environmental Engineering, 8093, Zürich, Switzerland
| | - Timothy R. Julian
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600, Dübendorf, Switzerland
- Swiss Tropical and Public Health, P.O. Box, 4001, Basel, Switzerland
- University of Basel, P.O. Box, 4002, Basel, Switzerland
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19
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Rowell CER, Dobrovolny HM. Energy Requirements for Loss of Viral Infectivity. FOOD AND ENVIRONMENTAL VIROLOGY 2020; 12:281-294. [PMID: 32757142 PMCID: PMC7405386 DOI: 10.1007/s12560-020-09439-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 07/31/2020] [Indexed: 06/11/2023]
Abstract
Outside the host, viruses will eventually lose their ability to infect cells due to conformational changes that occur to proteins on the viral capsid. In order to undergo a conformational change, these proteins require energy to activate the chemical reaction that leads to the conformational change. In this study, data from the literature is used to calculate the energy required for viral inactivation for a variety of different viruses by means of the Arrhenius equation. We find that some viruses (rhinovirus, poliovirus, human immunodeficiency virus, Alkhumra hemorrhagic fever virus, and hepatitis A virus) have high inactivation energies, indicative of breaking of a chemical double bond. We also find that several viruses (respiratory syncytial virus, poliovirus, and norovirus) have nonlinear Arrhenius plots, suggesting that there is more than a single pathway for inactivation of these viruses.
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Affiliation(s)
- Caroline E R Rowell
- Department of Chemistry, Wingate University, Hendersonville, NC, USA
- Department of Physics and Astronomy, Texas Christian University, Fort Worth, TX, USA
| | - Hana M Dobrovolny
- Department of Physics and Astronomy, Texas Christian University, Fort Worth, TX, USA.
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20
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Brooks YM, Spirito CM, Bae JS, Hong A, Mosier EM, Sausele DJ, Fernandez-Baca CP, Epstein JL, Shapley DJ, Goodman LB, Anderson RR, Glaser AL, Richardson RE. Fecal indicator bacteria, fecal source tracking markers, and pathogens detected in two Hudson River tributaries. WATER RESEARCH 2020; 171:115342. [PMID: 31841955 DOI: 10.1016/j.watres.2019.115342] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 11/21/2019] [Accepted: 11/25/2019] [Indexed: 05/08/2023]
Abstract
Volunteer monitoring in the Hudson River watershed since 2012 has identified that the Wallkill River and Rondout Creek tributary complex have elevated concentrations of the fecal indicator bacteria, enterococci. Concentrations of enterococci do not provide insight into the sources of pollution and are imperfect indicators of health risks. In 2017, the regular monthly volunteer monitoring campaign for culturable enterococci at 24 sites on the Wallkill and Rondout expanded to include: (1) culturable measurements of E. coli and quantification of E. coli and Enterococcus specific markers vis nanoscale qPCR, (2) microbial source tracking (MST) assays (avian, human, bovine, and equine) via real time PCR and nanoscale qPCR, and 3) quantification of 12 gastrointestinal pathogens including viruses, bacteria, and protozoa via nanoscale qPCR. Three human associated MST markers (HumM2, HF183, and B. theta) corroborated that human pollution was present in Rondout Creek and widespread in the Wallkill River. The presence of B. theta was associated with increased concentrations of culturable E. coli. Genes for adenovirus 40 and 41 conserved region, rotavirus A NSP3, E. coli eae and stx1, and Giardia lamblia 18S rRNA were detected in >45% of samples. Abundance of rotavirus A NSP3 genes was significantly correlated to the bovine marker gene, CowM3, though wild bird sources cannot be ruled out. This is the first study to investigate potential fecal pollution sources and pathogen concentrations in Hudson tributaries during the months of peak recreational use.
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Affiliation(s)
- Yolanda M Brooks
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Catherine M Spirito
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Justin S Bae
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Anna Hong
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Emma M Mosier
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Desiree J Sausele
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA
| | | | | | - Dan J Shapley
- Riverkeeper Inc, 20 Secor Road, Ossining, NY, 10562, USA
| | - Laura B Goodman
- Population Medicine and Diagnostic Sciences, Cornell University Animal Health Diagnostic Center, Ithaca, NY, 14853, USA
| | - Renee R Anderson
- Population Medicine and Diagnostic Sciences, Cornell University Animal Health Diagnostic Center, Ithaca, NY, 14853, USA
| | - Amy L Glaser
- Population Medicine and Diagnostic Sciences, Cornell University Animal Health Diagnostic Center, Ithaca, NY, 14853, USA
| | - Ruth E Richardson
- Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA.
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21
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Ahmed W, Payyappat S, Cassidy M, Harrison N, Besley C. Sewage-associated marker genes illustrate the impact of wet weather overflows and dry weather leakage in urban estuarine waters of Sydney, Australia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 705:135390. [PMID: 31838427 DOI: 10.1016/j.scitotenv.2019.135390] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 11/03/2019] [Accepted: 11/04/2019] [Indexed: 05/18/2023]
Abstract
This study investigates the impact of wet weather overflows (WWOs) at three estuarine locations in Sydney, NSW, Australia. WWOs can occur when infiltration of stormwater leads to an excess volume of flow within the sewerage system, resulting in the release of diluted sewage into the environment. Sewage contamination poses a risk to human health due to the presence of pathogens. The magnitude of sewage contamination was monitored using established and novel sewage-associated marker genes, Bacteroides HF183, pepper mild mottle virus (PMMoV), crAssphage CPQ_056, Lachnospiraceae (Lachno3) marker genes along with culturable fecal indicator bacteria (FIB) Escherichia coli (E. coli) and enterococci. Water samples were collected at two water depths (0.5 m below the water surface and 1 m above the bottom surface) during one dry weather and two storm events. Analysis of sewage-associated marker genes showed greater (i.e., 3-5 orders of magnitude) concentrations in water samples collected during the storm events compared to dry weather event. Water samples were also analysed for four animal feces-associated marker genes targeting avian (GFD), dog (BacCan-UCD), cow (cowM2) and horse (HoF597) species to determine the extent of animal fecal contamination. Among the four marker genes, cowM2 and HoF597 could not be detected, while GFD marker gene was consistently present and BacCan-UCD was occasionally detected. Overall results suggested that after rainfall, untreated sewage from WWOs was present at sampling locations. In addition, microbial source tracking (MST) monitoring was able to distinguish the presence of a leaking sewer impacting on the recreational area during dry weather condition. This study demonstrated the capability of the MST monitoring approach to understand sources (sewage or animal) of fecal contamination. This capability will greatly enhance management decisions assisting in the prioritisation of remediation efforts of the sewerage system to improve estuarine bathing water quality and diminish human health risk.
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Affiliation(s)
- Warish Ahmed
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Dutton Park, QLD 4102, Australia.
| | - Sudhi Payyappat
- Sydney Water, 1 Smith Street, Parramatta, NSW 2150, Australia
| | - Michele Cassidy
- Sydney Water, 1 Smith Street, Parramatta, NSW 2150, Australia
| | - Nathan Harrison
- Sydney Water, 1 Smith Street, Parramatta, NSW 2150, Australia
| | - Colin Besley
- Sydney Water, 1 Smith Street, Parramatta, NSW 2150, Australia
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22
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Padovan A, Kennedy K, Rose D, Gibb K. Microbial quality of wild shellfish in a tropical estuary subject to treated effluent discharge. ENVIRONMENTAL RESEARCH 2020; 181:108921. [PMID: 31757407 DOI: 10.1016/j.envres.2019.108921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 09/26/2019] [Accepted: 11/11/2019] [Indexed: 06/10/2023]
Abstract
Elevated faecal indicator levels in beaches around Darwin Harbour including near effluent outfalls have led to concerns about the safety of popular, locally harvested aquatic foods. To address these concerns, the impact of treated effluent discharge on the microbial quality of aquatic foods was assessed using culture-based and molecular tools. Seawater, shellfish (mangrove snails Telescopium and Nerita balteata, the local black lip oyster Saccostrea cucullata) and mud crabs (Scylla serrata) were collected from 13 sites close (impacted) and distal (reference) to two effluent discharge locations, in creeks and coastal areas. Sampling occurred over two dry seasons and one wet season. E. coli, typical sewage related pathogens, Salmonella and norovirus, and the molecular faecal marker Bacteroides, as well as naturally occurring marine bacteria, Vibrio parahaemolyticus and Vibrio vulnificus were tested in biota. E. coli and faecal coliforms were measured in water in water. The highest concentration of faecal coliforms in water was from the Buffalo Creek discharge site. At sites located in creeks including reference creeks, the highest concentrations of faecal coliforms in water were measured in the wet season compared to the dry season, whereas in coastal sites, no or only few (<10) faecal coliforms were detected. E. coli concentrations in both snail species were significantly higher in the wet season compared to the dry season (P < 0.0001) at both the treated effluent discharge sites and reference sites with some samples exceeding the acceptable Australian and New Zealand Food Standards (ANZFS) level based on E. coli levels in bivalves. E. coli concentrations in all of the S. cucullata samples were either below the detection limit or below the ANZFS limit for E. coli. No E. coli exceedances occurred in cooked mud crabs although low E. coli levels were measured in 3 cooked mud crab samples. Only one shellfish sample (T. telescopium) was positive for Salmonella. Norovirus and Bacteroides were not detected in any of the shellfish samples tested. V. parahaemolyticus and V. vulnificus were significantly more prevalent in shellfish samples during the wet season. Twelve virulent strains of V. parahaemolyticus were detected in T. telescopium and two in N. balteata. There was no significant difference in V. parahaemolyticus prevalence between sites. V. parahaemolyticus was detected in cooked S. serrata samples from three sites in the wet season and once in the 2016 dry season. V. vulnificus was detected in both T. telescopium and N. balteata, but not in any of the S. cucullata samples. One cooked crab meat sample from a reference site was positive for V. vulnificus. The prevalence of V. vulnificus was significantly higher at the reference sites compared to the discharge or potential impact sites. The lack of correlation between E. coli and targeted faecal pathogens in biota confirm that traditional faecal markers are not suitable surrogates for faecal pollution, at least not in the tropics. The higher prevalence of E. coli, V. parahaemolyticus and V. vulnificus in biota during the wet season compared to the dry season irrespective of treated sewage influence suggests that marine snails should not be harvested and consumed from creeks during the wet season. Any future aquaculture involving shellfish should consider these data when developing appropriate shellfish quality assurance protocols and for making decisions on where to situate farms.
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Affiliation(s)
- Anna Padovan
- Research Institute of the Environment and Livelihoods, Charles Darwin University, Darwin, Northern Territory, 0909, Australia.
| | - Karen Kennedy
- Power Water Corporation, Water Services, P.O. Box 37471, Winnellie, Northern Territory, 0821, Australia
| | - Dianne Rose
- Power Water Corporation, Water Services, P.O. Box 37471, Winnellie, Northern Territory, 0821, Australia
| | - Karen Gibb
- Research Institute of the Environment and Livelihoods, Charles Darwin University, Darwin, Northern Territory, 0909, Australia
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23
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Tran NH, Reinhard M, Khan E, Chen H, Nguyen VT, Li Y, Goh SG, Nguyen QB, Saeidi N, Gin KYH. Emerging contaminants in wastewater, stormwater runoff, and surface water: Application as chemical markers for diffuse sources. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 676:252-267. [PMID: 31048157 DOI: 10.1016/j.scitotenv.2019.04.160] [Citation(s) in RCA: 93] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 04/10/2019] [Accepted: 04/10/2019] [Indexed: 06/09/2023]
Abstract
Diffuse sources of pollution such as sewer leakages, sewer overflows, illicit discharges and stormwater runoff affect the urban surface water quality but often remain unknown. Therefore, the development of chemical markers for identifying and characterizing the origin of diffuse sources of pollution in urban surface waters is a requisite for protecting and managing urban water resources. In this study, the occurrence of 31 emerging contaminants (ECs) in untreated wastewater, treated wastewater, urban stormwater runoff, agricultural stormwater runoff, and freshwater bodies was investigated. Artificial sweeteners (ASs), pharmaceuticals and personal care products (PPCPs) were more frequently detected in the collected water samples. In raw wastewater, 21 target ECs were detected 100% in the collected samples with median concentrations ranging from 49.6 to 77,721 ng/L, while in freshwater bodies, only 13 compounds were found with detection frequency >50%. The median concentration of the majority of detected ECs in freshwater samples was below 100 ng/L. The suitability of ECs as chemical markers of diffuse sources in an urban watershed was assessed using a suite of criteria, including the detection frequency (DF), detection ratio (DR) (i.e. the ratio between median concentration and method quantification limit of a compound) and attenuation rates (i.e., biodegradation, sorption and abiotic degradation) in wastewater treatment processes. In addition, we propose a new key criterion, the concentration ratio (CR) of labile to conservative compounds, to evaluate the applicability of suitable chemical markers for source tracking. Using this new set of criteria (i.e. CR, DF, DR and attenuation rates), our analysis showed that among the investigated ECs, only acesulfame (ACE), acetaminophen (ACT), cyclamate (CYC), saccharin (SAC) were suitable as chemical markers of diffuse sources in surface waters. For caffeine (CF), N,N-diethyl-meta-toluamide (DEET), crotamiton (CTMT), triclocarban (TCC) and triclosan (TCS), their median concentration ratio to sucralose (SUC) in water bodies was consistently higher than that in raw wastewater, suggesting that these compounds might be unsuitable as chemical markers of sewage leakage in surface waters for this study area.
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Affiliation(s)
- Ngoc Han Tran
- NUS Environmental Research Institute, National University of Singapore, 5A Engineering Drive 1, T-Lab Building, Singapore 117411, Singapore; Institute of Research and Development, Duy Tan University, Da Nang 550000, Viet Nam.
| | - Martin Reinhard
- Department of Civil and Environmental Engineering, Stanford University, CA 94305, USA
| | - Eakalak Khan
- Department of Civil and Environmental Engineering, University of Nevada, Las Vegas (UNLV), 4505S Maryland Pkwy, Las Vegas, NV 89154, USA
| | - Huiting Chen
- NUS Environmental Research Institute, National University of Singapore, 5A Engineering Drive 1, T-Lab Building, Singapore 117411, Singapore
| | | | - Yiwen Li
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Shin Giek Goh
- Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576, Singapore
| | - Q B Nguyen
- Institute of Research and Development, Duy Tan University, Da Nang 550000, Viet Nam
| | - Nazanin Saeidi
- Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576, Singapore
| | - Karina Yew-Hoong Gin
- NUS Environmental Research Institute, National University of Singapore, 5A Engineering Drive 1, T-Lab Building, Singapore 117411, Singapore; Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576, Singapore.
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