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Tang L, Rhoads WJ, Eichelberg A, Hamilton KA, Julian TR. Applications of Quantitative Microbial Risk Assessment to Respiratory Pathogens and Implications for Uptake in Policy: A State-of-the-Science Review. ENVIRONMENTAL HEALTH PERSPECTIVES 2024; 132:56001. [PMID: 38728217 PMCID: PMC11086748 DOI: 10.1289/ehp12695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 02/28/2024] [Accepted: 03/08/2024] [Indexed: 05/12/2024]
Abstract
BACKGROUND Respiratory tract infections are major contributors to the global disease burden. Quantitative microbial risk assessment (QMRA) holds potential as a rapidly deployable framework to understand respiratory pathogen transmission and inform policy on infection control. OBJECTIVES The goal of this paper was to evaluate, motivate, and inform further development of the use of QMRA as a rapid tool to understand the transmission of respiratory pathogens and improve the evidence base for infection control policies. METHODS We conducted a literature review to identify peer-reviewed studies of complete QMRA frameworks on aerosol inhalation or contact transmission of respiratory pathogens. From each of the identified studies, we extracted and summarized information on the applied exposure model approaches, dose-response models, and parameter values, including risk characterization. Finally, we reviewed linkages between model outcomes and policy. RESULTS We identified 93 studies conducted in 16 different countries with complete QMRA frameworks for diverse respiratory pathogens, including SARS-CoV-2, Legionella spp., Staphylococcus aureus, influenza, and Bacillus anthracis. Six distinct exposure models were identified across diverse and complex transmission pathways. In 57 studies, exposure model frameworks were informed by their ability to model the efficacy of potential interventions. Among interventions, masking, ventilation, social distancing, and other environmental source controls were commonly assessed. Pathogen concentration, aerosol concentration, and partitioning coefficient were influential exposure parameters as identified by sensitivity analysis. Most (84%, n = 78 ) studies presented policy-relevant content including a) determining disease burden to call for policy intervention, b) determining risk-based threshold values for regulations, c) informing intervention and control strategies, and d) making recommendations and suggestions for QMRA application in policy. CONCLUSIONS We identified needs to further the development of QMRA frameworks for respiratory pathogens that prioritize appropriate aerosol exposure modeling approaches, consider trade-offs between model validity and complexity, and incorporate research that strengthens confidence in QMRA results. https://doi.org/10.1289/EHP12695.
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Affiliation(s)
- Lizhan Tang
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - William J. Rhoads
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Antonia Eichelberg
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Kerry A. Hamilton
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona, USA
- Biodesign Institute Center for Environmental Health Engineering, Arizona State University, Tempe, Arizona, USA
| | - Timothy R. Julian
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
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Clements E, Crank K, Nerenberg R, Atkinson A, Gerrity D, Hannoun D. Quantitative Microbial Risk Assessment Framework Incorporating Water Ages with Legionella pneumophila Growth Rates. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:6540-6551. [PMID: 38574283 PMCID: PMC11025131 DOI: 10.1021/acs.est.4c01208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 03/20/2024] [Accepted: 03/21/2024] [Indexed: 04/06/2024]
Abstract
Water age in drinking water systems is often used as a proxy for water quality but is rarely used as a direct input in assessing microbial risk. This study directly linked water ages in a premise plumbing system to concentrations of Legionella pneumophila via a growth model. In turn, the L. pneumophila concentrations were used for a quantitative microbial risk assessment to calculate the associated probabilities of infection (Pinf) and clinically severe illness (Pcsi) due to showering. Risk reductions achieved by purging devices, which reduce water age, were also quantified. The median annual Pinf exceeded the commonly used 1 in 10,000 (10-4) risk benchmark in all scenarios, but the median annual Pcsi was always 1-3 orders of magnitude below 10-4. The median annual Pcsi was lower in homes with two occupants (4.7 × 10-7) than with one occupant (7.5 × 10-7) due to more frequent use of water fixtures, which reduced water ages. The median annual Pcsi for homes with one occupant was reduced by 39-43% with scheduled purging 1-2 times per day. Smart purging devices, which purge only after a certain period of nonuse, maintained these lower annual Pcsi values while reducing additional water consumption by 45-62%.
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Affiliation(s)
- Emily Clements
- Southern
Nevada Water Authority, P.O. Box 99954, Las Vegas, Nevada 89193, United States
| | - Katherine Crank
- Southern
Nevada Water Authority, P.O. Box 99954, Las Vegas, Nevada 89193, United States
| | - Robert Nerenberg
- Department
of Civil & Environmental Engineering & Earth Science, University of Notre Dame, 156 Fitzpatrick Hall, Notre
Dame, Indiana 46556, United States
| | - Ariel Atkinson
- Southern
Nevada Water Authority, P.O. Box 99954, Las Vegas, Nevada 89193, United States
| | - Daniel Gerrity
- Southern
Nevada Water Authority, P.O. Box 99954, Las Vegas, Nevada 89193, United States
| | - Deena Hannoun
- Southern
Nevada Water Authority, P.O. Box 99954, Las Vegas, Nevada 89193, United States
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Liu S, Xia S, Zhang X, Cai X, Yang J, Hu Y, Zhou S, Wang H. Microbial communities exhibit distinct diversities and assembly mechanisms in rainwater and tap-water storage systems. WATER RESEARCH 2024; 253:121305. [PMID: 38367380 DOI: 10.1016/j.watres.2024.121305] [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: 12/18/2023] [Revised: 02/08/2024] [Accepted: 02/10/2024] [Indexed: 02/19/2024]
Abstract
Roof-harvested rainwater stored for potable and nonpotable usages represent a clean and sustainable water supply resource. However, the microbial dynamics and mechanisms of community assembly in long-termed operated rainwater storage systems remain elusive. In this study, characteristics of microbial communities in different habitats were systematically compared within rainwater and tap-water simulated storage systems (SWSSs) constructed with different tank materials (PVC, stainless steel and cement). Distinct microbial communities were observed between rainwater and tap-water SWSSs for both water and biofilm samples (ANOSIM, p < 0.05), with lower diversity indexes noted in rainwater samples. Notably, a divergent potential pathogen profile was observed between rainwater and tap-water SWSSs, with higher relative abundances of potential pathogens noted in rainwater SWSSs. Moreover, tank materials had a notable impact on microbial communities in rainwater SWSSs (ANOSIM, p < 0.05), rather than tap-water SWSSs, illustrating the distinct interplay between water chemistry and engineering factors in shaping the SWSS microbiomes. Deterministic processes contributed predominantly to the microbial community assembly in cement rainwater SWSSs and all tap-water SWSSs, which might be ascribed to the high pH levels in cement rainwater SWSSs and low-nutrient levels in all tap-water SWSSs, respectively. However, microbial communities in the PVC and stainless-steel rainwater SWSSs were mainly driven by stochastic processes. Overall, the results provided insights to the distinct microbial assembly mechanisms and potential health risks in stored roof-harvested rainwater, highlighting the importance of developing tailored microbial management strategies for the storage and utilization of rainwater.
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Affiliation(s)
- Sihang Liu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Siqing Xia
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
| | - Xiaodong Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Xucheng Cai
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Jinhao Yang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Yuxing Hu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Shuang Zhou
- School of Medicine, Tongji University, Shanghai 200092, China
| | - Hong Wang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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Carpio-Vallejo E, Düker U, Waldowski J, Nogueira R. Contribution of rooftop rainwater harvesting to climate adaptation in the city of Hannover: Water quality and health issues of rainwater storage in cisterns and ponds. Int J Hyg Environ Health 2024; 256:114320. [PMID: 38184969 DOI: 10.1016/j.ijheh.2024.114320] [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: 09/18/2023] [Revised: 12/19/2023] [Accepted: 01/02/2024] [Indexed: 01/09/2024]
Abstract
Rooftop rainwater harvesting systems and blue-green infrastructure are becoming important resilience alternatives for urban climate adaptation. This study sheds light on the largely unreported physicochemical and microbiological quality of private roof-harvested rainwater (RHRW). We aimed to identify the physicochemical and microbiological characteristics of RHRW, explore potential correlations between them and assess probable health risks associated with recreational interactions of children with the water. RHRW was collected from cisterns and ponds located in an inner courtyard in Hanover, Germany. Physicochemical parameters were measured on site and samples were collected once a month in two campaigns in 2020 and 2021. Escherichia coli concentrations ranged from 1 × 10° to 24.1 × 102 MPN/100 mL, Enterococci from 1 × 10° to 19.7 × 102 MPN/100 mL, Salmonella from 1 × 102 to 39 × 103 CFU/100 mL and Pseudomonas aeruginosa from 1 × 10° to 3 × 103 MPN/100 mL. Correlation analysis indicated potential relationships between bacteria, oxygen, and water temperature. The results of the health risk assessment indicated a potential risk of gastrointestinal illnesses due to exposure to Enterococci and Salmonella spp. present in the cisterns and ponds, highlighting the need for appropriate regulations and guidelines for RHRW aimed for non-potable uses. Blue-green infrastructure, when effectively managed and maintained, can offer benefits both by enhancing urban climate resilience and promoting citizens well-being.
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Affiliation(s)
| | - Urda Düker
- Gottfried Wilhelm Leibniz Universität Hannover, Welfengarten 1, 30167, Hannover, Germany
| | - Jessica Waldowski
- Grundstücksentwässerung, Stadtentwässerung Hannover, Sorststraße 16, 30165, Hannover, Germany
| | - Regina Nogueira
- Gottfried Wilhelm Leibniz Universität Hannover, Welfengarten 1, 30167, Hannover, Germany.
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Wang Q, Jiang G, Sun Z, Liang Y, Liu F, Shi J. Water quality and microecosystem of water tanks in karst mountainous area, Southwest China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:12948-12965. [PMID: 38236565 DOI: 10.1007/s11356-024-31959-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 01/06/2024] [Indexed: 01/19/2024]
Abstract
Karst mountainous areas in Southwest China, the world's largest bare karst area, are faced with growing water shortages. Rainwater harvesting plays an important role in alleviating water shortage. However, there remains a substantial gap in the research regarding the water quality of tanks. Water samples were seasonally collected from ten tanks to investigate the physicochemical properties, microbial communities, and their key influencing factors. The result showed that pH, turbidity, chroma, DOC, and CODMn exceeded drinking water guidelines. The alkaline pH value and the deterioration of sensory properties was the main feature of tank water, from which the over-standard rate of the uncleaned water tanks was higher. Moreover, principal component analyses suggested that tank water quality was influenced by human activities, catchment areas, and material cycling processes within the tanks, of which in-tank microbial activities were the most important driving factors in water quality variation. Proteobacteria, Actinobacteria, Bacteroidetes, Cyanobacteria, Firmicutes, and Verrucomicrobia were the predominant bacterial phyla in water tanks. Acinetobacter, Cyanobium-PCC-6307, CL500-29-marine-group, Candidatus-Aquiluna, and Exiguobacterium were the most abundant genera. The bacterial communities were significantly affected by the management practices. Higher relative abundance of Cyanobacteria and lower relative abundance of Proteobacteria was detected in the uncleaned tanks, which was a sign of tank water quality deterioration. The microbial community structure was closely related to the environmental factors. There was evidence that the water quality was affected by the existence of a microecosystem dominated by photosynthetic microorganisms in the water tanks. In addition, Acinetobacter, Enterobacter, Pseudomonas, and Legionella identified as the potential opportunistic pathogenic genera were frequently detected but the relative abundances except Acinetobacter were low in the tanks. Overall, our findings indicated that management style influences water quality and bacterial communities of tank water.
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Affiliation(s)
- Qigang Wang
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
- Key Laboratory of Karst Dynamics, MNR/GZAR, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, 541004, China
| | - Guanghui Jiang
- School of Civil Engineering and Architecture, Guangxi University, Nanning, 530004, China.
| | - Ziyong Sun
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
| | - Yueming Liang
- Key Laboratory of Karst Dynamics, MNR/GZAR, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, 541004, China
| | - Fan Liu
- Key Laboratory of Karst Dynamics, MNR/GZAR, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, 541004, China
- Pingguo Observation and Research Station for Karst Ecosystems, Pingguo, 531400, China
| | - Jie Shi
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
- Key Laboratory of Karst Dynamics, MNR/GZAR, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, 541004, China
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Nahusenay H, Tola A, Sisay Tessema T, Vipham J, Woldegiorgis AZ. Seasonal Comparison of Microbial Hygiene Indicators in Raw and Pasteurized Milk and Cottage Cheese Collected across Dairy Value Chain in Three Regions of Ethiopia. Foods 2023; 12:4377. [PMID: 38137180 PMCID: PMC10743099 DOI: 10.3390/foods12244377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 11/29/2023] [Accepted: 12/03/2023] [Indexed: 12/24/2023] Open
Abstract
A longitudinal design with a simple random sampling method was used to collect and compare microbial hygiene levels between the dry season (January to April) and wet season (June to August). A total of 456 milk and cottage cheese samples were collected from each site along the dairy value chain from three regions. Enumeration of total aerobic mesophilic bacteria (APC), total coliforms (TCC), and Escherichia coli (EC) was performed according to standard methods. Independent t-tests were employed to assess the significant variation at (p < 0.05) between the two seasons. The cumulative result of APC of 7.61 log cfu/mL and g and TCC of 3.50 log cfu/mL in the dry season were significantly higher than the wet season of 7.15 log cfu/mL and 2.49 log cfu/mL, respectively, whereas generic E. coli count (EC) was significantly higher in the wet season (0.70 log cfu/mL and g) than that in the dry season (0.40 log cfu/mL and g). The results of hygienic indicator microbial load significantly varied with season. Hence, hygienic milk production and handling practices that comprehend seasonal influence should be implemented to improve the safety of milk.
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Affiliation(s)
- Henok Nahusenay
- Center for Food Science and Nutrition, College of Natural Sciences, Addis Ababa University, New Graduate Building, Addis Ababa P.O. Box 1176, Ethiopia;
- Food Science and Nutrition Research Directorate, Ethiopian Institute of Agricultural Research, Addis Ababa P.O. Box 036, Ethiopia
| | - Alganesh Tola
- Holeta Agricultural Centre, Ethiopian Institute of Agricultural Research, Holeta P.O. Box 036, Ethiopia;
| | - Tesfaye Sisay Tessema
- Institute of Biotechnology, New Graduate Building, Addis Ababa University, New Graduate Building, Addis Ababa P.O. Box 1176, Ethiopia;
| | - Jessie Vipham
- Department of Animal Science and Industry, Kansas State University, 247 Weber Hall, Manhattan, KS 66506, USA;
| | - Ashagrie Zewdu Woldegiorgis
- Center for Food Science and Nutrition, College of Natural Sciences, Addis Ababa University, New Graduate Building, Addis Ababa P.O. Box 1176, Ethiopia;
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7
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Fu S, Zhang Y, Wang R, Qiu Z, Song W, Yang Q, Shen L. A novel culture-enriched metagenomic sequencing strategy effectively guarantee the microbial safety of drinking water by uncovering the low abundance pathogens. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 345:118737. [PMID: 37657296 DOI: 10.1016/j.jenvman.2023.118737] [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: 04/02/2023] [Revised: 07/21/2023] [Accepted: 07/31/2023] [Indexed: 09/03/2023]
Abstract
Assessing the presence of waterborne pathogens and antibiotic resistance genes (ARGs) is crucial for managing the environmental quality of drinking water sources. However, detecting low abundance pathogens in such settings is challenging. In this study, a workflow was developed to enrich for broad spectrum pathogens from drinking water samples. A mock community was used to evaluate the effectiveness of various enrichment broths in detecting low-abundance pathogens. Monthly metagenomic surveillance was conducted in a drinking water source from May to September 2021, and water samples were subjected to five enrichment procedures for 6 h to recover the majority of waterborne bacterial pathogens. Oxford Nanopore Technology (ONT) was used for metagenomic sequencing of enriched samples to obtain high-quality pathogen genomes. The results showed that selective enrichment significantly increased the proportions of targeted bacterial pathogens. Compared to direct metagenomic sequencing of untreated water samples, targeted enrichment followed by ONT sequencing significantly improved the detection of waterborne pathogens and the quality of metagenome-assembled genomes (MAGs). Eighty-six high-quality MAGs, including 70 pathogen MAGs, were obtained from ONT sequencing, while only 12 MAGs representing 10 species were obtained from direct metagenomic sequencing of untreated water samples. In addition, ONT sequencing improved the recovery of mobile genetic elements and the accuracy of phylogenetic analysis. This study highlights the urgent need for efficient methodologies to detect and manage microbial risks in drinking water sources. The developed workflow provides a cost-effective approach for environmental management of drinking water sources with microbial risks. The study also uncovered pathogens that were not detected by traditional methods, thereby advancing microbial risk management of drinking water sources.
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Affiliation(s)
- Songzhe Fu
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Northwest University, Xi'an, 710069, China; Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University), Ministry of Education, 116023, China.
| | - Yixiang Zhang
- CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences. Shanghai, China; University of Chinese Academy of Sciences, Shanghai, China
| | - Rui Wang
- Key Laboratory of Environment Controlled Aquaculture (Dalian Ocean University), Ministry of Education, 116023, China
| | - Zhiguang Qiu
- School of Environment and Energy, Shenzhen Graduate School, Peking University, Shenzhen, 518055, China
| | - Weizhi Song
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, SAR, Hong Kong, China
| | - Qian Yang
- Center for Microbial Ecology and Technology, Ghent University, Ghent, Belgium
| | - Lixin Shen
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Northwest University, Xi'an, 710069, China.
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Castier M, de Barros Barreto P. Economic attractiveness of domestic rainwater harvesting in Brazilian cities. DISCOVER WATER 2023; 3:9. [PMID: 38013984 PMCID: PMC10234589 DOI: 10.1007/s43832-023-00033-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 05/11/2023] [Indexed: 11/29/2023]
Abstract
Brazil is the fifth largest country by area in the world, with a variety of climates in its territory. This work assesses the economic attractiveness of domestic rainwater harvesting direct feed systems, for the replacement of non-drinking water, in 148 locations of the Brazilian territory considering hourly rainfall data for the 14-year period between 2008 and 2021. The water tariff and consumption data for each location were also considered along with estimated hourly and monthly consumption patterns. With annual operating expenses at 1% of the capital expenditure and an annual discount rate of 8%, the net present value for the 14-year period is positive in only 15 locations, which are among those with the highest water tariffs in the country. The results of these base case simulations discourage the installation of domestic RWH systems in most of the Brazilian locations considered. However, the results also show that, depending on house occupancy, filtration equipment cost, water tariff, and catchment area, outcomes more favorable to the installation of RWH systems are obtained, especially in cities of Brazil's southern and southeastern regions.
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Affiliation(s)
- Marcelo Castier
- Chemical Engineering Program, Texas A &M University at Qatar, Education City, Doha, Qatar
| | - Paula de Barros Barreto
- Facultad de Ciencias de la Ingeniería, Universidad Paraguayo Alemana, Lopez de Vega 1279, San Lorenzo, Paraguay
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Jahne MA, Schoen ME, Kaufmann A, Pecson BM, Olivieri A, Sharvelle S, Anderson A, Ashbolt NJ, Garland JL. Enteric pathogen reduction targets for onsite non-potable water systems: A critical evaluation. WATER RESEARCH 2023; 233:119742. [PMID: 36848851 PMCID: PMC10084472 DOI: 10.1016/j.watres.2023.119742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 02/10/2023] [Accepted: 02/11/2023] [Indexed: 06/18/2023]
Abstract
Onsite non-potable water systems (ONWS) collect and treat local source waters for non-potable end uses such as toilet flushing and irrigation. Quantitative microbial risk assessment (QMRA) has been used to set pathogen log10-reduction targets (LRTs) for ONWS to achieve the risk benchmark of 10-4 infections per person per year (ppy) in a series of two efforts completed in 2017 and 2021. In this work, we compare and synthesize the ONWS LRT efforts to inform the selection of pathogen LRTs. For onsite wastewater, greywater, and stormwater, LRTs for human enteric viruses and parasitic protozoa were within 1.5-log10 units between 2017 and 2021 efforts, despite differences in approaches used to characterize pathogens in these waters. For onsite wastewater and greywater, the 2017 effort used an epidemiology-based model to simulate pathogen concentrations contributed exclusively from onsite waste and selected Norovirus as the viral reference pathogen; the 2021 effort used municipal wastewater pathogen data and cultivable adenoviruses as the reference viral pathogen. Across source waters, the greatest differences occurred for viruses in stormwater, given the newly available municipal wastewater characterizations used for modeling sewage contributions in 2021 and the different selection of reference pathogens (Norovirus vs. adenoviruses). The roof runoff LRTs support the need for protozoa treatment, but these remain difficult to characterize due to the pathogen variability in roof runoff across space and time. The comparison highlights adaptability of the risk-based approach, allowing for updated LRTs as site specific or improved information becomes available. Future research efforts should focus on data collection of onsite water sources.
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Affiliation(s)
- Michael A Jahne
- Office of Research and Development, U.S. Environmental Protection Agency, 26 W. Martin Luther King Dr., Cincinnati, OH 45268, USA.
| | - Mary E Schoen
- Soller Environmental, LLC, 3022 King St., Berkeley, CA 94703, USA
| | - Anya Kaufmann
- Trussell Technologies, Inc., 1939 Harrison St., Oakland, CA 94612, USA
| | - Brian M Pecson
- Trussell Technologies, Inc., 1939 Harrison St., Oakland, CA 94612, USA
| | | | - Sybil Sharvelle
- Colorado State University, Department of Civil and Environmental Engineering, 1372 Campus Delivery, Fort Collins, CO 80523, USA
| | - Anita Anderson
- Minnesota Department of Health, 625 Robert St. N, St. Paul, MN 55164, USA
| | | | - Jay L Garland
- Office of Research and Development, U.S. Environmental Protection Agency, 26 W. Martin Luther King Dr., Cincinnati, OH 45268, USA
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Alja'fari J, Sharvelle S, Brinkman NE, Jahne M, Keely S, Wheaton EA, Garland J, Welty C, Sukop MC, Meixner T. Characterization of roof runoff microbial quality in four U.S. cities with varying climate and land use characteristics. WATER RESEARCH 2022; 225:119123. [PMID: 36166998 PMCID: PMC10236986 DOI: 10.1016/j.watres.2022.119123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 09/09/2022] [Accepted: 09/14/2022] [Indexed: 06/04/2023]
Abstract
Roof runoff has the potential to serve as an important local water source in regions with growing populations and limited water supply. Given the scarcity of guidance regulating the use of roof runoff, a need exists to characterize the microbial quality of roof runoff. The objective of this 2-year research effort was to examine roof runoff microbial quality in four U.S. cities: Fort Collins, CO; Tucson, AZ; Baltimore, MD; and Miami, FL. Seven participants, i.e., homeowners and schools, were recruited in each city to collect roof runoff samples across 13 precipitation events. Sample collection was done as part of a citizen science approach. The presence and concentrations of indicator organisms and potentially human-infectious pathogens in roof runoff were determined using culture methods and digital droplet polymerase chain reaction (ddPCR), respectively. The analyzed pathogens included Salmonella spp., Campylobacter spp., Giardia duodenalis, and Cryptosporidium parvum. Several factors were evaluated to study their influence on the presence of potentially human-infectious pathogens including the physicochemical characteristics (total suspended solids, volatile suspended solids, total dissolved solids, chemical oxygen demand, and turbidity) of roof runoff, concentrations of indicator organisms, presence/absence of trees, storm properties (rainfall depth and antecedent dry period), percent of impervious cover surrounding each sampling location, seasonality, and geographical location. E. coli and enterococci were detected in 73.4% and 96.2% of the analyzed samples, respectively. Concentrations of both E. coli and enterococci ranged from <0 log10 to >3.38 log10 MPN/100 mL. Salmonella spp. invA, Campylobacter spp. ceuE, and G. duodenalis β - giardin gene targets were detected in 8.9%, 2.5%, and 5.1% of the analyzed samples, respectively. Campylobacter spp. mapA and C. parvum 18S rRNA gene targets were not detected in any of the analyzed samples. The detection of Salmonella spp. invA was influenced by the geographical location of the sampling site (Chi-square p-value < 0.001) as well as the number of antecedent dry days prior to a rain event (p-value = 0.002, negative correlation). The antecedent dry period was negatively correlated with the occurrence of Campylobacter spp. ceuE as well (p-value = 0.07). On the other hand, the presence of G. duodenalis β-giardin in roof runoff was positively correlated with rainfall depth (p-value = 0.05). While physicochemical parameters and impervious area were not found to be correlated with the presence/absence of potentially human-infectious pathogens, significant correlations were found between meteorological parameters and the presence/absence of potentially human-infectious pathogens. Additionally, a weak, yet significant positive correlation, was found only between the concentrations of E. coli and those of Giardia duodenalis β-giardin. This dataset represents the largest-scale study to date of enteric pathogens in U.S. roof runoff collections and will inform treatment targets for different non-potable end uses for roof runoff. However, the dataset is limited by the low percent detection of bacterial and protozoan pathogens, an issue that is likely to persist challenging the characterization of roof runoff microbial quality given sampling limitations related to the volume and number of samples.
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Affiliation(s)
- Jumana Alja'fari
- Department of Civil and Environmental Engineering, Colorado State University, 700 Meridian Avenue, Fort Collins, CO 80523, USA.
| | - Sybil Sharvelle
- Department of Civil and Environmental Engineering, Colorado State University, 700 Meridian Avenue, Fort Collins, CO 80523, USA
| | - Nichole E Brinkman
- Office of Research and Development, U.S. Environmental Protection Agency, 26 West Martin Luther King Dr., Cincinnati, OH 45268, USA
| | - Michael Jahne
- Office of Research and Development, U.S. Environmental Protection Agency, 26 West Martin Luther King Dr., Cincinnati, OH 45268, USA
| | - Scott Keely
- Office of Research and Development, U.S. Environmental Protection Agency, 26 West Martin Luther King Dr., Cincinnati, OH 45268, USA
| | - Emily A Wheaton
- Office of Research and Development, U.S. Environmental Protection Agency, 26 West Martin Luther King Dr., Cincinnati, OH 45268, USA
| | - Jay Garland
- Office of Research and Development, U.S. Environmental Protection Agency, 26 West Martin Luther King Dr., Cincinnati, OH 45268, USA
| | - Claire Welty
- Department of Chemical, Biological, and Environmental Engineering and Center for Urban Environmental Research and Education, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA
| | - Michael C Sukop
- Department of Earth and Environment, Florida International University, 11200 SW 8th Street, Miami, FL 33199, USA
| | - Thomas Meixner
- Department of Hydrology and Atmospheric Sciences, The University of Arizona, 1133 E. James E. Rogers Way, Tucson, AZ 85721, USA
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11
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Morgado ME, Hudson CL, Chattopadhyay S, Ta K, East C, Purser N, Allard S, Ferrier MD, Sapkota AR, Sharma M, Goldstein RR. The effect of a first flush rainwater harvesting and subsurface irrigation system on E. coli and pathogen concentrations in irrigation water, soil, and produce. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 843:156976. [PMID: 35768032 DOI: 10.1016/j.scitotenv.2022.156976] [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: 04/12/2022] [Revised: 06/10/2022] [Accepted: 06/21/2022] [Indexed: 06/15/2023]
Abstract
Climate change is stressing irrigation water sources, necessitating the evaluation of alternative waters such as harvested rainwater to determine if they meet water quality and food safety standards. We collected water, soil, and produce samples between June and August 2019 from two vegetable rain garden (VRG) sites in Frederick, Maryland that harvest rainwater using a first flush system, and deliver this water to produce through subsurface irrigation. The raised VRG beds include layers of gravel, sand, and soil that act as filters. We recorded the average surface soil moisture in each bed as well as antecedent precipitation. All water (n = 29), soil (n = 55), and produce (n = 57) samples were tested for generic E. coli using standard membrane filtration, and water samples were also tested for Salmonella spp. and Listeria monocytogenes by selective enrichment. No Salmonella spp. or L. monocytogenes isolates were detected in any water samples throughout the study period. Average E. coli levels from all harvested rainwater samples at both sites (1.2 and 24.4 CFU/100 mL) were well below the Good Agricultural Practices food safety guidelines. Only 7 % (3/44) of produce samples from beds irrigated with harvested rainwater were positive for E. coli. E. coli levels in soil samples were positively associated with average surface soil moisture (r2 = 0.13, p = 0.007). Additionally, E. coli presence in water samples was marginally associated with a shorter length of antecedent dry period (fewer days since preceding rainfall) (p = 0.058). Our results suggest that harvested rainwater collected through a first flush system and applied to produce through subsurface irrigation meets current food safety standards. Soil moisture monitoring could further reduce E. coli contamination risks from harvested rainwater-irrigated produce. First flush and subsurface irrigation systems could help mitigate climate change-related water challenges while protecting food safety and security.
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Affiliation(s)
- Michele E Morgado
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, USA.
| | - Claire L Hudson
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, USA; Department of Biology, Hood College, Frederick, MD, USA.
| | - Suhana Chattopadhyay
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, USA.
| | - Kaitlin Ta
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, USA.
| | - Cheryl East
- United States Department of Agriculture, Agricultural Research Service, Northeast Area, Beltsville Agricultural Research Center, Environmental Microbial and Food Safety Laboratory, Beltsville, MD, USA.
| | - Nathan Purser
- Department of Biology, Hood College, Frederick, MD, USA.
| | - Sarah Allard
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, USA.
| | - M Drew Ferrier
- Department of Biology, Hood College, Frederick, MD, USA.
| | - Amy R Sapkota
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, USA.
| | - Manan Sharma
- United States Department of Agriculture, Agricultural Research Service, Northeast Area, Beltsville Agricultural Research Center, Environmental Microbial and Food Safety Laboratory, Beltsville, MD, USA.
| | - Rachel Rosenberg Goldstein
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, USA.
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12
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Ishaq S, Sadiq R, Chhipi-Shrestha G, Farooq S, Hewage K. Developing an Integrated "Regression-QMRA method" to Predict Public Health Risks of Low Impact Developments (LIDs) for Improved Planning. ENVIRONMENTAL MANAGEMENT 2022; 70:633-649. [PMID: 35543727 DOI: 10.1007/s00267-022-01657-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 04/25/2022] [Indexed: 06/14/2023]
Abstract
Worldwide Low Impact Developments (LIDs) are used for sustainable stormwater management; however, both the stormwater and LIDs carry microbial pathogens. The widespread development of LIDs is likely to increase human exposure to pathogens and risk of infection, leading to unexpected disease outbreaks in urban communities. The risk of infection from exposure to LIDs has been assessed via Quantitative Microbial Risk Assessment (QMRA) during the operation of these infrastructures; no effort is made to evaluate these risks during the planning phase of LID treatment train in urban communities. We developed a new integrated "Regression-QMRA method" by examining the relationship between pathogens' concentration and environmental variables. Applying of this methodology to a planned LID train shows that the predicted disease burden of diarrhea from Campylobacter is highest (i.e. 16.902 DALYs/1000 persons/yr) during landscape irrigation and playing on the LID train, followed by Giardia, Cryptosporidium, and Norovirus. These results illustrate that the risk of microbial infection can be predicted during the planning phase of LID treatment train. These predictions are of great value to municipalities and decision-makers to make informed decisions and ensure risk-based planning of stormwater systems before their development.
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Affiliation(s)
- Sadia Ishaq
- School of Engineering, University of British Columbia, Okanagan Campus, Kelowna, BC, V1V 1V7, Canada
| | - Rehan Sadiq
- School of Engineering, University of British Columbia, Okanagan Campus, Kelowna, BC, V1V 1V7, Canada.
| | - Gyan Chhipi-Shrestha
- School of Engineering, University of British Columbia, Okanagan Campus, Kelowna, BC, V1V 1V7, Canada
| | - Shaukat Farooq
- King Fahd University of Petroleum and Minerals (KFUPM), Dhahran, 31261, Saudi Arabia
| | - Kasun Hewage
- School of Engineering, University of British Columbia, Okanagan Campus, Kelowna, BC, V1V 1V7, Canada
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13
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Fiorentino A, Lofrano G, Cucciniello R, Carotenuto M, Motta O, Proto A, Rizzo L. Disinfection of roof harvested rainwater inoculated with E. coli and Enterococcus and post-treatment bacterial regrowth: Conventional vs solar driven advanced oxidation processes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 801:149763. [PMID: 34438135 DOI: 10.1016/j.scitotenv.2021.149763] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 08/15/2021] [Accepted: 08/15/2021] [Indexed: 06/13/2023]
Abstract
Solar driven advanced oxidation processes (AOPs) (an alternative solar photo Fenton like process (SPF), sunlight/H2O2 (SHP) and sunlight/chlorine (SCL)) and respective dark conditions, were compared for the first time to conventional (chlorination and UV-C radiation) disinfection processes, in the inactivation of E. coli and Entero strains inoculated in real roof-harvested rainwater (RHRW), to evaluate their possible safe use for crop irrigation. In this regard, bacterial regrowth was also evaluated 6, 12, 24 and 48 h after disinfection treatment. The SPF, using iminodisuccinic acid (IDS)-Cu complex as catalyst, was optimized (H2O2/IDS-Cu 55/1 best molar ratio) under mild conditions (spontaneous pH) and sunlight. The faster inactivation kinetics were observed for the SCL process (k = 1.473 min-1, t1/2 = 0.47 min for E. coli and k = 1.193 min-1, t1/2 = 0.57 min for Entero), while the most effective processes in controlling bacterial regrowth were SPF and SCL. Although UV-C radiation (0-1.3 × 104 μW s cm-2 dose range) was the second faster disinfection process (k = 1.242 min-1, t1/2 = 0.55 min for E. coli and k = 1.150 min-1, t1/2 = 0.60 min for Entero), it was the less effective process in controlling bacterial regrowth (>10 CFU 100 mL-1 already after 6 h post-treatment incubation). According to the bacterial inactivation and regrowth tests carried out in this work, SPF and SCL are interesting options for RHRW disinfection, in case of effluent use for crop irrigation.
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Affiliation(s)
- A Fiorentino
- Department of Chemistry and Biology "A. Zambelli", University of Salerno, via Giovanni Paolo II 132, 84084 Fisciano, SA, Italy
| | - G Lofrano
- Centro Servizi Metereologici e Tecnologici Avanzati (CeSMA), University of Naples Federico II, Via Cinthia 21, 80126 Naples, Italy.
| | - R Cucciniello
- Department of Chemistry and Biology "A. Zambelli", University of Salerno, via Giovanni Paolo II 132, 84084 Fisciano, SA, Italy
| | - M Carotenuto
- Department of Chemistry and Biology "A. Zambelli", University of Salerno, via Giovanni Paolo II 132, 84084 Fisciano, SA, Italy
| | - O Motta
- Department of Medicine Surgery and Dentistry, University of Salerno, via S. Allende, 84081 Baronissi, SA, Italy
| | - A Proto
- Department of Chemistry and Biology "A. Zambelli", University of Salerno, via Giovanni Paolo II 132, 84084 Fisciano, SA, Italy
| | - L Rizzo
- Department of Civil Engineering, University of Salerno, via Giovanni Paolo II 132, 84084 Fisciano, SA, Italy
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14
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Kusumawardhana A, Zlatanovic L, Bosch A, van der Hoek JP. Microbiological Health Risk Assessment of Water Conservation Strategies: A Case Study in Amsterdam. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:2595. [PMID: 33807661 PMCID: PMC7967349 DOI: 10.3390/ijerph18052595] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 02/24/2021] [Accepted: 03/03/2021] [Indexed: 11/24/2022]
Abstract
The aim of this study was to assess the health risks that may arise from the implementation of greywater reuse and rainwater harvesting for household use, especially for toilet flushing. In addition, the risk of cross connections between these systems and the drinking water system was considered. Quantitative microbial risk assessment (QMRA) is a method that uses mathematical modelling to estimate the risk of infection when exposure to pathogens happens and was used in this study to assess the health risks. The results showed that using rainwater without prior treatment for toilet flushing poses an annual infection risk from L. pneumophila at 0.64 per-person-per-year (pppy) which exceeds the Dutch standard of 10-4 pppy. The use of untreated greywater showed a risk that is below the standard. However, treatment is recommended due to the ability of P. aeruginosa to grow in the reuse system. Moreover, showering and drinking with cross-connected water has a high annual infection risk that exceeds the standard due to contact with Staphylococcus aureus and E. coli O157:H7. Several measures can be implemented to mitigate the risks such as treating the greywater and rainwater with a minimum of 5-log removal, closing the toilet lid while flushing, good design of greywater and rainwater collection systems, and rigorous plumbing installation procedures.
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Affiliation(s)
- Agung Kusumawardhana
- Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, P.O. Box 5, 2600 AA Delft, The Netherlands; (A.K.); (L.Z.)
| | - Ljiljana Zlatanovic
- Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, P.O. Box 5, 2600 AA Delft, The Netherlands; (A.K.); (L.Z.)
- Amsterdam Institute for Advanced Metropolitan Solutions, Kattenburgerstraat 5, 1018 JA Amsterdam, The Netherlands
- Water Supply Company Noord-Holland PWN, Rijksweg 501, 1991 AS Velserbroek, The Netherlands
| | - Arne Bosch
- Waternet, P.O. Box 94370, 1090 GJ Amsterdam, The Netherlands;
| | - Jan Peter van der Hoek
- Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, P.O. Box 5, 2600 AA Delft, The Netherlands; (A.K.); (L.Z.)
- Amsterdam Institute for Advanced Metropolitan Solutions, Kattenburgerstraat 5, 1018 JA Amsterdam, The Netherlands
- Waternet, P.O. Box 94370, 1090 GJ Amsterdam, The Netherlands;
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15
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Hozalski RM, LaPara TM, Zhao X, Kim T, Waak MB, Burch T, McCarty M. Flushing of Stagnant Premise Water Systems after the COVID-19 Shutdown Can Reduce Infection Risk by Legionella and Mycobacterium spp. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:15914-15924. [PMID: 33232602 DOI: 10.1021/acs.est.0c06357] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
There is concern about potential exposure to opportunistic pathogens when reopening buildings closed due to the COVID-19 pandemic. In this study, water samples were collected before, during, and after flushing showers in five unoccupied (i.e., for ∼2 months) university buildings with quantification of opportunists via a cultivation-based assay (Legionella pneumophila only) and quantitative PCR. L. pneumophila were not detected by either method; Legionella spp., nontuberculous mycobacteria (NTM), and Mycobacterium avium complex (MAC), however, were widespread. Using quantitative microbial risk assessment (QMRA), the estimated risks of illness from exposure to L. pneumophila and MAC via showering were generally low (i.e., less than a 10-7 daily risk threshold), with the exception of systemic infection risk from MAC exposure in some buildings. Flushing rapidly restored the total chlorine (as chloramine) residual and decreased bacterial gene targets to building inlet concentrations within 30 min. During the postflush stagnation period, the residual chlorine dissipated within a few days and bacteria rebounded, approaching preflush concentrations after 6-7 days. These results suggest that flushing can quickly improve water quality in unoccupied buildings, but the improvement may only last a few days.
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Affiliation(s)
- Raymond M Hozalski
- Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, Minneapolis 55455, Minnesota, United States
| | - Timothy M LaPara
- Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, Minneapolis 55455, Minnesota, United States
| | - Xiaotian Zhao
- Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, Minneapolis 55455, Minnesota, United States
| | - Taegyu Kim
- Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, Minneapolis 55455, Minnesota, United States
| | - Michael B Waak
- Norwegian University of Science and Technology, Trondheim 7031, Norway
- Department of Infrastructure, SINTEF Community, Trondheim 7031, Norway
| | - Tucker Burch
- Agricultural Research Service, U.S. Department of Agriculture, Marshfield, Wisconsin 54449, United States
| | - Michael McCarty
- School of Public Health, University of Minnesota, Minneapolis 55455, Minnesota, United States
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16
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Ishaq S, Sadiq R, Farooq S, Chhipi-Shrestha G, Hewage K. Investigating the public health risks of low impact developments at residential, neighbourhood, and municipal levels. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 744:140778. [PMID: 32717466 PMCID: PMC7336927 DOI: 10.1016/j.scitotenv.2020.140778] [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: 04/05/2020] [Revised: 07/03/2020] [Accepted: 07/04/2020] [Indexed: 05/04/2023]
Abstract
Low Impact Developments (LIDs) employ a series of vegetative techniques to retain rainfall close to the site of origin. Although LIDs offer sustainable runoff management, these infrastructures can be considered a risk to public health due to the presence of pathogens in the runoff and human exposure to contaminated water held in and transported by LIDs. The objective of this study is to examine the disease burden of Gastrointestinal illness (GI) from exposure to LIDs at the residential, neighbourhood, and municipal levels. The authors conducted a meta-analysis of literature on three water features: (1) harvested rainwater obtained from LIDs, (2) surface water, and (3) floodwater. A set of 32 studies were systematically selected to collect values of risks of infection and expressed as the disease burden, i.e. disability adjusted life years (DALYs). The results showed that the percentage of GI illness exceeding the health guidelines were high for harvested rainwater, i.e. 22% of annual disease burden exceeded the WHO guidelines (0.001 DALYs/1000 persons), and 2% exceeded the US EPA guidelines (5.75 DALYs/1000 bathers). Among the six exposures for harvested rainwater, exposure to spray irrigation, exceeded US EPA guidelines whereas; five exposures, i.e. flushing, hosing, daily shower, spray irrigation, and children playing, surpassed the WHO guidelines. Considering LID treatment, the values of annual disease burden from all the selected barriers were below US EPA guidelines however, these values exceeded the WHO guidelines for three barriers i.e. water plaza, grass swale, and open storage ponds. These findings provide a broader perspective of the disease burden associated with LIDs and emphasise to consider the type of exposures and required treatment barriers for developing LID infrastructures in urban areas.
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Affiliation(s)
- Sadia Ishaq
- School of Engineering, University of British Columbia, Okanagan Campus, Kelowna, BC V1V 1V7, Canada.
| | - Rehan Sadiq
- School of Engineering, University of British Columbia, Okanagan Campus, Kelowna, BC V1V 1V7, Canada.
| | - Shaukat Farooq
- King Fahd University of Petroleum and Minerals (KFUPM), Dhahran, 31261, Saudi Arabia
| | - Gyan Chhipi-Shrestha
- School of Engineering, University of British Columbia, Okanagan Campus, Kelowna, BC V1V 1V7, Canada.
| | - Kasun Hewage
- School of Engineering, University of British Columbia, Okanagan Campus, Kelowna, BC V1V 1V7, Canada.
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17
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Reyneke B, Hamilton KA, Fernández-Ibáñez P, Polo-López MI, McGuigan KG, Khan S, Khan W. EMA-amplicon-based sequencing informs risk assessment analysis of water treatment systems. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 743:140717. [PMID: 32679496 DOI: 10.1016/j.scitotenv.2020.140717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 06/29/2020] [Accepted: 07/01/2020] [Indexed: 06/11/2023]
Abstract
Illumina amplicon-based sequencing was coupled with ethidium monoazide bromide (EMA) pre-treatment to monitor the total viable bacterial community and subsequently identify and prioritise the target organisms for the health risk assessment of the untreated rainwater and rainwater treated using large-volume batch solar reactor prototypes installed in an informal settlement and rural farming community. Taxonomic assignments indicated that Legionella and Pseudomonas were the most frequently detected genera containing opportunistic bacterial pathogens in the untreated and treated rainwater at both sites. Additionally, Mycobacterium, Clostridium sensu stricto and Escherichia/Shigella displayed high (≥80%) detection frequencies in the untreated and/or treated rainwater samples at one or both sites. Numerous exposure scenarios (e.g. drinking, cleaning) were subsequently investigated and the health risk of using untreated and solar reactor treated rainwater in developing countries was quantified based on the presence of L. pneumophila, P. aeruginosa and E. coli. The solar reactor prototypes were able to reduce the health risk associated with E. coli and P. aeruginosa to below the 1 × 10-4 annual benchmark limit for all the non-potable uses of rainwater within the target communities (exception of showering for E. coli). However, the risk associated with intentional drinking of untreated or treated rainwater exceeded the benchmark limit (E. coli and P. aeruginosa). Additionally, while the solar reactor treatment reduced the risk associated with garden hosing and showering based on the presence of L. pneumophila, the risk estimates for both activities still exceeded the annual benchmark limit. The large-volume batch solar reactor prototypes were thus able to reduce the risk posed by the target bacteria for non-potable activities rainwater is commonly used for in water scarce regions of sub-Saharan Africa. This study highlights the need to assess water treatment systems in field trials using QMRA.
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Affiliation(s)
- B Reyneke
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa
| | - K A Hamilton
- School for Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ 85281, United States; The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, Tempe, AZ 85281, United States
| | - P Fernández-Ibáñez
- Plataforma Solar de Almeria-CIEMAT, P.O. Box 22, Tabernas, Almería, Spain; Nanotechnology and Integrated BioEngineering Centre, School of Engineering, University of Ulster, Newtownabbey, Northern Ireland, United Kingdom
| | - M I Polo-López
- Plataforma Solar de Almeria-CIEMAT, P.O. Box 22, Tabernas, Almería, Spain
| | - K G McGuigan
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - S Khan
- Faculty of Health Sciences, University of Johannesburg, PO Box 17011, Doornfontein 2028, South Africa
| | - W Khan
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa.
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18
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Jamal R, Mubarak S, Sahulka SQ, Kori JA, Tajammul A, Ahmed J, Mahar RB, Olsen MS, Goel R, Weidhaas J. Informing water distribution line rehabilitation through quantitative microbial risk assessment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 739:140021. [PMID: 32758946 DOI: 10.1016/j.scitotenv.2020.140021] [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: 04/27/2020] [Revised: 06/01/2020] [Accepted: 06/04/2020] [Indexed: 06/11/2023]
Abstract
Poor urban water quality has been linked to diminished source water quality, poorly functioning water treatment systems and infiltration into distribution lines after treatment resulting in microbiological contamination. With limited funding to rehabilitate distribution lines, developing nations need tools to identify the areas of greatest concern to human health so as to target cost effective remediation approaches. Herein, a case study of Hyderabad, Pakistan was used to demonstrate the efficacy of combining quantitative microbial risk assessment (QMRA) for multiple pathogens with spatial distribution system modeling to identify areas for pipe rehabilitation. Abundance of Escherichia coli, Enterococcus (enterococci), Salmonella spp., Shigella spp., Giardia intestinalis, Vibrio cholera, norovirus GI and adenovirus 40/41, were determined in 85 locations including the source water, treatment plant effluent and the city distribution lines. Bayesian statistics and Monte Carlo simulations were used in the QMRA to account for left-censored microbial abundance distributions. Bacterial and viral abundances in the distribution system samples decreased as follows: 9400 ± 19,800 norovirus gene copies/100 mL (average ± standard deviation, 100% of samples positive); 340 ± 2200 enterococci CFU/100 mL (94%), 71 ± 97 Shigella sp. CFU/100 mL (97%), 60 ± 360 E. coli CFU/100 mL (89%), 35 ± 79 adenovirus gene copies/100 mL (100%), and 21 ± 46 Salmonella sp. CFU/100 mL (76%). The QMRA revealed unacceptable probabilities of illness (>1 in 10,000 illness level) from the four exposure routes considered (drinking water, or only showering, tooth brushing, and rinsing vegetables consumed raw). Disease severity indices based on the QMRA combined with mapping the distribution system revealed areas for targeted rehabilitation. The combined intensive sampling, risk assessment and mapping can be used in low- and middle-income countries to target distribution system rehabilitation efforts and improve health outcomes.
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Affiliation(s)
- Rubayat Jamal
- Civil and Environmental Engineering, University of Utah, 110 Central Campus Drive Suite 2000, Salt Lake City, UT 84112, USA
| | - Shaista Mubarak
- US Pakistan Center for Advanced Studies in Water, Mehran University of Engineering and Technology, Jamshoro, 76062, Sindh, Pakistan
| | - Sierra Q Sahulka
- Civil and Environmental Engineering, University of Utah, 110 Central Campus Drive Suite 2000, Salt Lake City, UT 84112, USA
| | - Junaid A Kori
- US Pakistan Center for Advanced Studies in Water, Mehran University of Engineering and Technology, Jamshoro, 76062, Sindh, Pakistan
| | - Ayesha Tajammul
- US Pakistan Center for Advanced Studies in Water, Mehran University of Engineering and Technology, Jamshoro, 76062, Sindh, Pakistan
| | - Jamil Ahmed
- US Pakistan Center for Advanced Studies in Water, Mehran University of Engineering and Technology, Jamshoro, 76062, Sindh, Pakistan
| | - Rasool B Mahar
- US Pakistan Center for Advanced Studies in Water, Mehran University of Engineering and Technology, Jamshoro, 76062, Sindh, Pakistan
| | | | - Ramesh Goel
- Civil and Environmental Engineering, University of Utah, 110 Central Campus Drive Suite 2000, Salt Lake City, UT 84112, USA
| | - Jennifer Weidhaas
- Civil and Environmental Engineering, University of Utah, 110 Central Campus Drive Suite 2000, Salt Lake City, UT 84112, USA.
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19
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Maguvu TE, Bezuidenhout CC, Kritzinger R, Tsholo K, Plaatjie M, Molale-Tom LG, Mienie CM, Coertze RD. Combining physicochemical properties and microbiome data to evaluate the water quality of South African drinking water production plants. PLoS One 2020; 15:e0237335. [PMID: 32790793 PMCID: PMC7425920 DOI: 10.1371/journal.pone.0237335] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 07/23/2020] [Indexed: 12/17/2022] Open
Abstract
Anthropogenic activities in catchments used for drinking water production largely contaminates source waters, and this may impact the quality of the final drinking water product. These contaminants may also affect taxonomic and functional profiles of the bacterial communities in the drinking water. Here, we report an integrated insight into the microbiome and water quality of four water treatment plants (NWC, NWE, WCA and NWG) that supply portable water to communities in South Africa. A new scoring system based on combined significant changes of physicochemical parameters and microbial abundance from raw to treated water was used to evaluate the effectiveness of the treatment plants at water purification. Physicochemical parameters which include total soluble solids, turbidity, pH, nitrites and phosphorus among others, were measured in source, treated, and distributed water. There were general statistically significant (P ≤ 0.05) differences between raw and treated water, demonstrating the effectiveness of the purification process. Illumina sequencing of the 16S rRNA gene was used for taxonomic profiling of the microbial communities and this data was used to infer functional attributes of the communities. Structure and composition of the bacterial communities differed significantly (P < 0.05) among the treatment plants, only NWE and NWG showed no significant differences (P > 0.05), this correlated with the predicted functional profile of the microbial communities obtained from Phylogenetic Investigation of Communities by Reconstruction of Observed States (PICRUSt), as well as the likely pollutants of source water. Bacteroidetes, Chlorobi and Fibrobacteres significantly differed (P < 0.05) between raw and distributed water. PICRUSt inferred a number of pathways involved in the degradation of xenobiotics such as Dichlorodiphenyltrichloroethane, atrazine and polycyclic aromatic hydrocarbons. More worryingly, was the presence of pathways involved in beta-lactam resistance, potential pathogenic Escherichia coli infection, Vibrio cholerae infection, and Shigellosis. Also present in drinking and treated water were OTUs associated with a number of opportunistic pathogens.
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Affiliation(s)
- Tawanda E. Maguvu
- Unit for Environmental Sciences and Management - Microbiology, North-West University, Potchefstroom, South Africa
- * E-mail:
| | - Cornelius C. Bezuidenhout
- Unit for Environmental Sciences and Management - Microbiology, North-West University, Potchefstroom, South Africa
| | - Rinaldo Kritzinger
- Unit for Environmental Sciences and Management - Microbiology, North-West University, Potchefstroom, South Africa
| | - Karabo Tsholo
- Unit for Environmental Sciences and Management - Microbiology, North-West University, Potchefstroom, South Africa
| | - Moitshepi Plaatjie
- Unit for Environmental Sciences and Management - Microbiology, North-West University, Potchefstroom, South Africa
| | - Lesego G. Molale-Tom
- Unit for Environmental Sciences and Management - Microbiology, North-West University, Potchefstroom, South Africa
| | - Charlotte M. Mienie
- Unit for Environmental Sciences and Management - Microbiology, North-West University, Potchefstroom, South Africa
| | - Roelof D. Coertze
- Unit for Environmental Sciences and Management - Microbiology, North-West University, Potchefstroom, South Africa
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Huang C, Shen Y, Smith RL, Dong S, Nguyen TH. Effect of disinfectant residuals on infection risks from Legionella pneumophila released by biofilms grown under simulated premise plumbing conditions. ENVIRONMENT INTERNATIONAL 2020; 137:105561. [PMID: 32088542 DOI: 10.1016/j.envint.2020.105561] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 02/05/2020] [Accepted: 02/06/2020] [Indexed: 06/10/2023]
Abstract
The ubiquitous presence of biofilms in premise plumbing and stagnation, which commonly occurs in premise plumbing, can exacerbate the decay of chlorine residual in drinking water. Using biofilms grown in a simulated premise plumbing setup fed directly with freshly treated water at two full-scale water treatment plants, we previously determined the mass transfer coefficients for chlorine decay in premise plumbing. These coefficients coupled with inactivation kinetics of L. pneumophila released from biofilms reported previously were integrated into a Monte Carlo framework to estimate the infection risk of biofilm-derived L. pneumophila from 1 to 48 h of stagnation. The annual infection risk was significantly higher when water stayed stagnant for up to 48 h in pipes covered internally with biofilms, compared to clean pipes without biofilms. The decay of residual chlorine due to biofilms during 48-hour stagnation led to up to 6 times increase in the annual infection risk compared to the case where biofilms was absent. Global sensitivity analysis revealed that the rate of L. pneumophila detachment from biofilms and the decay of chlorine residual during stagnation are the two most important factors influencing the infection risks. Stagnation caused by water use patterns and water-saving devices in the premise plumbing can lead to increased infection risk by biofilm-derived L. pneumophila. Overall, this study's findings suggested that biofilms could induce chlorine decay and consequently increase L. pneumophila infection risk. Thus, reducing stagnation, maintaining residual chlorine, and suppressing biofilm growth could contribute to better management of L. pneumophila infection risk.
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Affiliation(s)
- Conghui Huang
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
| | - Yun Shen
- Department of Chemical and Environmental Engineering, The University of California, Riverside, Riverside, CA 92521, United States
| | - Rebecca L Smith
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
| | - Shengkun Dong
- Guangdong Engineering Technology Research Center of Water Security Regulation and Control for Southern China, Key Laboratory of Water Cycle and Water Security in Southern China of Guangdong Higher Education Institute, School of Civil Engineering, Sun Yat-sen University, Guangzhou, Guangdong 510275, China.
| | - Thanh H Nguyen
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States.
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Zhang X, Xia S, Zhao R, Wang H. Effect of temperature on opportunistic pathogen gene markers and microbial communities in long-term stored roof-harvested rainwater. ENVIRONMENTAL RESEARCH 2020; 181:108917. [PMID: 31759642 DOI: 10.1016/j.envres.2019.108917] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 11/07/2019] [Accepted: 11/10/2019] [Indexed: 06/10/2023]
Abstract
Roof-harvested rainwater (RHRW) has received increasing attention in recent years as an alternative water source for domestic use, yet its biological stability during storage is not fully understood. This study investigated the effects of temperature (4 °C, 20 °C and 30 °C) on the microbiological characteristics of RHRW over a storage period of 60 days by targeting different microbial groups including total bacteria and fecal indictor Escherichia coli, bacterial opportunistic pathogen genera and species (Legionella spp, Legionella pneumophila, Mycobacterium spp, Mycobacterium avium, Pseudomonas aeruginosa), and two amoebas (Acanthamoeba and Vermamoeba vermiformis). The rainwater chemistry demonstrated no obvious change during storage. The highest biomass was observed in RHRW stored at 30 °C, as measured by heterotrophic bacterial counts, adenosine triphosphate, and 16S rRNA gene numbers. Gene markers of E. coli, Legionella spp., P. aeruginosa, and V. vermiformis were detected in fresh RHRW and can persist during RHRW storage; whereas P. aeruginosa was the only species demonstrated significant regrowth at higher storage temperatures (P < 0.05). Acanthamoeba spp. was only detected in RHRW after 50 days of storage at three investigated temperatures, highlighting increased health risks in long-term stored RHRW. Bacterial community compositions were significantly different in RHRW stored at different temperatures, with increased variations among triplicate storage bottles noted at higher temperatures along with storage time. The results provide insights into RHRW storage practices in terms of mitigating microbial contamination risks.
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Affiliation(s)
- Xiaodong Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Siqing Xia
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China
| | - Renzun Zhao
- Civil, Architectural and Environmental Engineering Department, North Carolina Agricultural and Technical State University, Greensboro, NC 27411, USA
| | - Hong Wang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.
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22
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Bae S, Maestre JP, Kinney KA, Kirisits MJ. An examination of the microbial community and occurrence of potential human pathogens in rainwater harvested from different roofing materials. WATER RESEARCH 2019; 159:406-413. [PMID: 31121408 DOI: 10.1016/j.watres.2019.05.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 04/29/2019] [Accepted: 05/09/2019] [Indexed: 05/24/2023]
Abstract
While harvested rainwater can serve as an alternative water supply, microbial contaminants within the collection system can negatively affect water quality. Here, we investigated the impact of roofing material on the microbial quality of rainwater freshly harvested from pilot-scale roofs (concrete tile, cool, green, Galvalume® metal, and asphalt fiberglass shingle). The microbial quality of freshly harvested rainwater from six rain events over two years was analyzed by high-throughput sequencing and culture-dependent and -independent techniques. The concentrations of total coliform were significantly different among rainwaters harvested from the various roofing materials (p-value >0.05). However, the fecal coliform concentrations and the copy numbers of Enterococcus 23S rRNA genes and total Bacteria 16S rRNA genes did not vary by type of roofing material in a statistically significant way. Potential human pathogens such as Legionella, Escherichia coli O157:H7, Shiga-toxin-producing Escherichia coli, and adenovirus were detected at least once in rainwater harvested from the different roofing materials, even though the lowest occurrence of those potential human pathogens was noted from the metal roof. Also, substantial variation in the microbial communities from the different roofing materials was observed at the family and genus levels. These results demonstrate that the type of roofing material affects the microbial quality of freshly harvested rainwater, indicating that the choice of roofing material could shape the microbial community structure entering a rainwater storage tank. Given that detection of potential pathogens in the freshly harvested rainwater also differed between roofing materials, the type of roofing used to capture rainwater needs to be considered in rainwater harvesting system design, particularly if the water is intended for potable use.
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Affiliation(s)
- Sungwoo Bae
- Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, E1A 07-03, 11576, Singapore.
| | - Juan P Maestre
- Department of Civil, Architectural, and Environmental Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Kerry A Kinney
- Department of Civil, Architectural, and Environmental Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Mary Jo Kirisits
- Department of Civil, Architectural, and Environmental Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
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White Teeth and Healthy Skeletons for All: The Path to Universal Fluoride-Free Drinking Water in Tanzania. WATER 2019. [DOI: 10.3390/w11010131] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Fluorosis has been prevalent in the great East African Rift Valley (EARV) since before this region was given a name. In the Tanganyika days, Germans reported elevated fluoride concentrations in natural waters. In the 1930s, the clear relationship between high fluoride level and mottling of teeth was established. Since then, the global research community has engaged in the battle to provide fluoride-free drinking water, and the battle is not yet won for low-income communities. An applicable concept for fluoride-free drinking water in the EARV was recently presented, using the Kilimanjaro as a rainwater harvesting park. The Kilimanjaro concept implies that rainwater is harvested, stored on the Kilimanjaro mountains, gravity-transported to the point of use, eventually blended with natural water and treated for distribution. This article provides a roadmap for the implementation of the Kilimanjaro concept in Tanzania. Specifically, the current paper addresses the following: (i) presents updated nationwide information on fluoride contaminated areas, (ii) discusses the quality and quantity of rainwater, and current rainwater harvesting practices in Tanzania, (iii) highlights how low-cost water filters based on Fe0/biochar can be integrating into rainwater harvesting (RWH) systems to provide clean drinking water, and (iv) discusses the need for strict regulation of RWH practices to optimize water collection and storage, while simplifying the water treatment chain, and recommends strict analytical monitoring of water quality and public education to sustain public health in the EARV. In summary, it is demonstrated that, by combining rainwater harvesting and low-cots water treatment methods, the Kilimanjaro concept has the potential to provide clean drinking water, and overcome fluorosis on a long-term basis. However, a detailed design process is required to determine: (i) institutional roles, and community contributions and participation, (ii) optimal location and sizing of conveyance and storage facilities to avoid excessive pumping costs, and (iii) project funding mechanisms, including prospects for government subsidy. By drawing attention to the Kilimanjaro concept, the article calls for African engineers and scientists to take the lead in translating this concept into reality for the benefit of public health, while simultaneously increasing their self-confidence to address other developmental challenges pervasive in Africa.
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24
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Walker JT. The influence of climate change on waterborne disease and Legionella: a review. Perspect Public Health 2019; 138:282-286. [PMID: 30156484 DOI: 10.1177/1757913918791198] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Climate change is predicted to have a major impact on people's lives with the recent extreme weather events and varying abnormal temperature profiles across the world raising concerns. The impacts of global warming are already being observed, from rising sea levels and melting snow and ice to changing weather patterns. Scientists state unequivocally that these trends cannot be explained by natural variability in climate alone. Human activities, especially the burning of fossil fuels, have warmed the earth by dramatically increasing concentrations of heat-trapping gases in the atmosphere; as these concentrations increase, the more the earth will warm. Climate change and related extreme weather events are being exacerbated sooner than has previously been considered and are already adversely affecting ecosystems and human health by increasing the burden and type of disease at a local level. Changes to the marine environment and freshwater supplies already affect significant parts of the world's population and warmer temperatures, especially in more temperate regions, may see an increased spread and transmission of diseases usually associated with warmer climes including, for example, cholera and malaria; these impacts are likely to become more severe in a greater number of countries. This review discusses the impacts of climate change including changes in infectious disease transmission, patterns of waterborne diseases and the likely consequences of climate change due to warmer water, drought, higher rainfall, rising sea levels and flooding.
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Affiliation(s)
- J T Walker
- Public Health England, Porton, Salisbury SP1 3DX, UK
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25
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Chubaka CE, Whiley H, Edwards JW, Ross KE. Lead, Zinc, Copper, and Cadmium Content of Water from South Australian Rainwater Tanks. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:E1551. [PMID: 30041401 PMCID: PMC6068815 DOI: 10.3390/ijerph15071551] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 07/16/2018] [Accepted: 07/20/2018] [Indexed: 01/22/2023]
Abstract
Rainwater is consumed for drinking water in many parts of Australia, either preferentially over municipal water or in regional or remote areas, because rainwater is the primary source of water. Previous rainwater studies in other areas in Australia have shown the levels of some metals to be above the Australian Drinking Water Guidelines (ADWG). This study assessed the level of metals in rainwater harvested in the Adelaide region. Water samples were collected from 53 tanks from three different sampling corridors. A total of 365 water samples were analysed for lead, zinc, copper, and cadmium using atomic absorption spectrophotometry. In 47 out of the 53 tanks, lead was above the ADWG of 0.01 ppm in at least one sample (with 180/365 samples above 0.01 ppm). Zinc was above the ADWG (3.0 ppm) in 53/365 samples, copper was above the ADWG (2.0 ppm) in eight samples out of 365 samples, and cadmium was above the ADWG (0.002 ppm) in 19 samples out of 365 samples. These data are consistent with other studies of rainwater quality in Australia. Comparisons of levels of metals and volume of rainfall in the sampling and preceding month, roof material, and tank material, the presence of a first-flush device, sampling corridor, and sample pH showed that the roof material was related to higher levels of metals. There was a significant relationship between sampling corridors and the levels of lead and zinc. Nine of the tanks surveyed had filters installed. There was a small, but statistically significant, decrease in the levels of metals that passed through a filter prior to collection but, in those samples, filters did not remove metals to below guideline concentrations. An estimate of exposure, and a brief discussion of health risks as a result of exposure to metals, is presented.
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Affiliation(s)
- Chirhakarhula E Chubaka
- Environmental Health, College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide 5001, Australia.
| | - Harriet Whiley
- Environmental Health, College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide 5001, Australia.
| | - John W Edwards
- Environmental Health, College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide 5001, Australia.
| | - Kirstin E Ross
- Environmental Health, College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide 5001, Australia.
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26
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Steege L, Moore G. The presence and prevalence of Legionella spp in collected rainwater and its aerosolisation during common gardening activities. Perspect Public Health 2018; 138:254-260. [PMID: 29969060 DOI: 10.1177/1757913918786322] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
AIMS To determine the presence and prevalence of Legionella spp in domestic rainwater storage butts and to quantify its aerosolisation when collected rainwater is used for common gardening activities. METHODS Volunteers were asked to take a water sample from their garden rainwater storage butt. The presence of Legionella was determined using quantitative polymerase chain reaction (qPCR). Two new rainwater storage butts were installed on-site at PHE Porton and positioned in sunlight or in the shade. Ambient conditions and those within the two 'experimental' water butts were continually monitored. A cyclone air sampler was used to detect the presence of Legionella in the air when collected rainwater was poured from a watering can or delivered via a hosepipe attached to a submersible water butt pump. RESULTS A total of 63 volunteers provided water samples from 113 different rainwater storage butts. Legionella spp was detected in 107 of these samples at a mean concentration of 4.7 × 104 genomic units l-1. Two of these samples also contained L. pneumophila. The water butt positioned in the shade stored water at a significantly lower temperature than that exposed to sunlight. While the concentration of Legionella was significantly higher in this cooler water, meteorological conditions rather than conditions within the water butt had the greatest effect upon Legionella concentration. No Legionella was detected in the air when rainwater was poured from a watering can. However, using a hose pipe on a 'fine spray' setting increased both the number of organisms detected in the air and their dissemination. CONCLUSION In this study, Legionella spp were common contaminants of collected rainwater. However, the use of rainwater for common gardening activities should not be discouraged. Aerosolisation of Legionella when using a watering can is minimal and any increased risk associated with hose pipe use can be mitigated by using a coarse spray setting.
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Affiliation(s)
- L Steege
- Biosafety, Air and Water Microbiology Group, National Infection Service, Public Health England, Salisbury, UK.,School of Biosciences and Medicine, University of Surrey, Guildford, UK
| | - G Moore
- Biosafety, Air and Water Microbiology Group, National Infection Service, Public Health England, Porton Down, Salisbury SP4 0JG, UK
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27
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Lundy L, Revitt M, Ellis B. An impact assessment for urban stormwater use. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:19259-19270. [PMID: 29082472 DOI: 10.1007/s11356-017-0547-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 10/23/2017] [Indexed: 06/07/2023]
Abstract
Stormwater has the potential to provide a non-potable water supply which requires less treatment than municipal wastewaters with the added benefit of reducing pollution and erosion issues in receiving water bodies. However, the adoption of stormwater collection and use as an accepted practice requires that the perceived risks, particularly those associated with public health, are addressed. This paper considers the human health concerns associated with stormwater quality when used for a range of non-potable applications using E. coli, a commonly found pollutant in urban stormwater which is also widely included in human health-based water quality standards and guidelines. Based on a source-pathway-receptor model, scores are allocated, on a scale of 0 to 5, to benchmark increasing the likelihoods of exposure to stormwater during different occupational and non-occupational applications and magnitude of impacts which may result. The impacts are assessed by comparing median stormwater E. coli levels with the reported guideline levels relating to different stormwater uses. Combination of the exposure and impact scores provides an overall risk score for each stormwater application. Low or medium risks are shown to be associated with most stormwater uses except for domestic car washing and occupational irrigation of edible raw food crops where the predicted highest levels of risk posed by median E. coli levels in stormwater necessitate the introduction of remedial actions.
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Affiliation(s)
- Lian Lundy
- Urban Pollution Research Centre, Middlesex University, The Burroughs, Hendon, London, NW4 4BT, UK.
| | - Michael Revitt
- Urban Pollution Research Centre, Middlesex University, The Burroughs, Hendon, London, NW4 4BT, UK
| | - Bryan Ellis
- Urban Pollution Research Centre, Middlesex University, The Burroughs, Hendon, London, NW4 4BT, UK
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28
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Chidamba L, Korsten L. Relative proportions of E. coli and Enterococcus spp. may be a good indicator of potential health risks associated with the use of roof harvested rainwater stored in tanks. ENVIRONMENTAL MONITORING AND ASSESSMENT 2018; 190:177. [PMID: 29488034 DOI: 10.1007/s10661-018-6554-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 02/13/2018] [Indexed: 06/08/2023]
Abstract
A total of 285 water samples were collected from 71 roof harvested rainwater tanks from four villages in different provinces over a two-year (2013-2014) period during the early (October to December) and late (January to March) rainy season. Water quality was evaluated based on Escherichia coli, faecal coliforms and Enterococcus spp. prevalence using the IDEXX Quanti-Tray quantification system. Real-Time PCR was used to analyse a subset of 168 samples for the presence of Shigella spp., Salmonella spp. and E. coli virulence genes (stx1, stx2 and eaeA). Escherichia coli were detected in 44.1% of the samples, Enterococcus spp. in 57.9% and faecal coliforms in 95.7%. The most prevalent E. coli concentrations in harvested rainwater were observed in 29.1% of samples and 22.5% for Enterococcus spp. and, were within 1-10 cfu/100 ml and 10-100 cfu/100 ml, respectively, whereas those for faecal coliforms (36.6%) were within 100-1000 cfu/100 ml. On average 16.8% of the samples had neither E. coli nor Enterococcus spp. detected, while 33.9% had only Enterococcus spp. and 23.7% had only E. coli. E. coli and Enterococcus spp. were detected together in 25.5% of the samples. Evaluation of samples for potential pathogenic bacteria showed all tested samples to be negative for the Shigella spp. ipaH gene, while five tested positive for Salmonella ipaB gene. None of the samples tested positive for the stx1 and stx2 genes, and only two tested positive for the eaeA gene. These findings are potentially useful in the development of a simplified risk assessment strategy based on the concentrations of indicator bacteria.
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Affiliation(s)
- Lizyben Chidamba
- Research Group for Plant Health and Food Safety, Department of Plant and Soil Sciences, University of Pretoria, Room: 2-18, Hatfield Campus, Agriculture Building, Private Bag X20, Hatfield/Pretoria, South Africa
| | - Lise Korsten
- Research Group for Plant Health and Food Safety, Department of Plant and Soil Sciences, University of Pretoria, Room: 2-18, Hatfield Campus, Agriculture Building, Private Bag X20, Hatfield/Pretoria, South Africa.
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Waso M, Khan S, Khan W. Development and small-scale validation of a novel pigeon-associated mitochondrial DNA source tracking marker for the detection of fecal contamination in harvested rainwater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 615:99-106. [PMID: 28963900 DOI: 10.1016/j.scitotenv.2017.09.229] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 09/18/2017] [Accepted: 09/21/2017] [Indexed: 06/07/2023]
Abstract
The current study was aimed at designing and validating (on a small-scale) a novel pigeon mitochondrial DNA (mtDNA) microbial source tracking (MST) marker for the detection of pigeon fecal matter in harvested rainwater. The pigeon mtDNA MST marker was designed to target the mtDNA Cytochrome b gene by employing mismatch amplification mutation assay kinetics. The pigeon marker was validated by screening 69 non-pigeon and 9 pigeon fecal samples. The host-sensitivity of the assay was determined as 1.00 while the host-specificity of the assay was 0.96. Harvested rainwater samples (n=60) were screened for the prevalence of the marker with the mtDNA Cytochrome b marker detected in 78% of the samples. Bayes' theorem was applied to calculate the conditional probability of the marker detecting true pigeon contamination and the marker subsequently displayed a 99% probability of detecting true pigeon contamination in the harvested rainwater samples. In addition, the mtDNA Cytochrome b marker displayed high concurrence frequencies versus heterotrophic bacteria (78.3%), E. coli (73.3%), total coliforms (71.1%) and fecal coliforms (66.7%). This study thus validates that targeting mtDNA for the design of source tracking markers may be a valuable tool to detect avian fecal contamination in environmental waters.
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Affiliation(s)
- M Waso
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa
| | - S Khan
- Faculty of Health and Applied Sciences, Namibia University of Science and Technology, 13 Storch Street, Private Bag 13388, Windhoek 9000, Namibia
| | - W Khan
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa.
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Chubaka CE, Whiley H, Edwards JW, Ross KE. Microbiological Values of Rainwater Harvested in Adelaide. Pathogens 2018; 7:E21. [PMID: 29419793 PMCID: PMC5874747 DOI: 10.3390/pathogens7010021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 01/23/2018] [Accepted: 02/04/2018] [Indexed: 11/22/2022] Open
Abstract
In Australia, rainwater is an important source of water for many households. Unlike municipal water, rainwater is often consumed untreated. This study investigated the potential contamination of rainwater by microorganisms. Samples from 53 rainwater tanks across the Adelaide region were collected and tested using Colilert™ IDEXX Quanti-Tray*/2000. Twenty-eight out of the 53 tanks (53%) contained Escherichia coli. Samples collected from ten tanks contained E. coli at concentrations exceeding the limit of 150 MPN/100 mL for recreational water quality. A decline in E. coli was observed in samples collected after prolonged dry periods. Rainwater microbiological values depended on the harvesting environment conditions. A relationship was found between mounted TV antenna on rooftops and hanging canopies; and E. coli abundance. Conversely, there was no relationship between seasonality and E. coli or roof and tank structure materials and E. coli. In several tanks used for drinking water, samples collected prior to and after filtration showed that the filtration systems were not always successful at completely removing E. coli. These results differed from a study undertaken in the laboratory that found that a commercially available in-bench 0.45 µm filter cartridge successfully reduced E. coli in rainwater to 0 MPN/100 mL. After running a total of 265 L of rainwater which contained high levels of E. coli through the filter (half of the advertised filter lifespan), the filter cartridge became blocked, although E. coli remained undetected in filtered water. The difference between the laboratory study and field samples could be due to improper maintenance or installation of filters or recontamination of the faucet after filtration. The presence of E. coli in water that is currently used for drinking poses a potential health concern and indicates the potential for contamination with other waterborne pathogens.
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Affiliation(s)
- Chirhakarhula Emmanuel Chubaka
- Environmental Health, College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide 5001, South Australia.
| | - Harriet Whiley
- Environmental Health, College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide 5001, South Australia.
| | - John W Edwards
- Environmental Health, College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide 5001, South Australia.
| | - Kirstin E Ross
- Environmental Health, College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide 5001, South Australia.
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Waso M, Khan S, Khan W. Microbial source tracking markers associated with domestic rainwater harvesting systems: Correlation to indicator organisms. ENVIRONMENTAL RESEARCH 2018; 161:446-455. [PMID: 29216491 DOI: 10.1016/j.envres.2017.11.043] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 11/03/2017] [Accepted: 11/26/2017] [Indexed: 05/24/2023]
Abstract
Domestic rainwater harvesting (tank water) systems were screened for the presence of a panel of microbial source tracking (MST) markers and traditional indicator organisms. The indicator organisms were enumerated utilizing traditional culture-based methods, while the MST markers were quantified by quantitative PCR (qPCR). The indicators Escherichia coli (E. coli) and enterococci were also quantified using qPCR. Correlations and concurrence between these parameters were then investigated to determine which markers could be utilized to supplement traditional indicator analysis. Quantitative PCR analysis indicated that Bacteroides HF183, adenovirus, Lachnospiraceae and E. coli were detected and quantifiable in 100% of the tank water samples collected throughout the sampling period, while human mitochondrial DNA (mtDNA) was quantifiable in 90% of the tank water samples and Bifidobacterium adolescentis (B. adolescentis) and enterococci were quantifiable in 67% of the tank water samples, respectively. Significant positive correlations were recorded for Lachnospiraceae versus heterotrophic bacteria (p = 0.000), adenovirus versus E. coli (culturing) (p = 0.000) and heterotrophic bacteria (p = 0.024), the HF183 marker versus E. coli (qPCR) (p = 0.024) and B. adolescentis versus fecal coliforms (p = 0.037). In addition, 100% concurrence was observed for the HF183 marker, adenovirus and Lachnospiraceae versus E. coli (qPCR), enterococci (qPCR) and heterotrophic bacteria, amongst others. Based on the correlations and the concurrence analysis, the HF183 marker, Lachnospiraceae and adenovirus may be utilized to supplement indicator organism analysis for the monitoring of harvested rainwater quality.
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Affiliation(s)
- M Waso
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag ×1, Stellenbosch, 7602, South Africa
| | - S Khan
- Faculty of Health and Applied Sciences, Namibia University of Science and Technology, 13 Storch Street, Private Bag 13388, Windhoek, Namibia
| | - W Khan
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag ×1, Stellenbosch, 7602, South Africa.
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Waso M, Dobrowsky PH, Hamilton KA, Puzon G, Miller H, Khan W, Ahmed W. Abundance of Naegleria fowleri in roof-harvested rainwater tank samples from two continents. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:5700-5710. [PMID: 29230646 DOI: 10.1007/s11356-017-0870-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 11/28/2017] [Indexed: 05/24/2023]
Abstract
Roof-harvested rainwater (RHRW) has been used as an alternative source of water in water scarce regions of many countries. The microbiological and chemical quality of RHRW has been questioned due to the presence of bacterial and protozoan pathogens. However, information on the occurrence of pathogenic amoeba in RHRW tank samples is needed due to their health risk potential and known associations with opportunistic pathogens. Therefore, this study aims to determine the quantitative occurrence of Naegleria fowleri in RHRW tank samples from Southeast Queensland (SEQ), Australia (AU), and the Kleinmond Housing Scheme located in Kleinmond, South Africa (SA). In all, 134 and 80 RHRW tank samples were collected from SEQ, and the Kleinmond Housing Scheme, Western Cape, SA, respectively. Quantitative PCR (qPCR) assays were used to measure the concentrations of N. fowleri, and culture-based methods were used to measure fecal indicator bacteria (FIB) Escherichia coli (E. coli) and Enterococcus spp. Of the 134 tank water samples tested from AU, 69 and 62.7% were positive for E. coli, and Enterococcus spp., respectively. For the SA tank water samples, FIB analysis was conducted for samples SA-T41 to SA-T80 (n = 40). Of the 40 samples analyzed from SA, 95 and 35% were positive for E. coli and Enterococcus spp., respectively. Of the 134 water samples tested in AU, 15 (11.2%) water samples were positive for N. fowleri, and the concentrations ranged from 1.7 × 102 to 3.6 × 104 gene copies per 100 mL of water. Of the 80 SA tank water samples screened for N. fowleri, 15 (18.8%) tank water samples were positive for N. fowleri and the concentrations ranged from 2.1 × 101 to 7.8 × 104 gene copies per 100 mL of tank water. The prevalence of N. fowleri in RHRW tank samples from AU and SA thus warrants further development of dose-response models for N. fowleri and a quantitative microbial risk assessment (QMRA) to inform and prioritize strategies for reducing associated public health risks.
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Affiliation(s)
- Monique Waso
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa
| | - Penelope Heather Dobrowsky
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa
| | - Kerry Ann Hamilton
- Drexel University, 3141 Chestnut Street, Philadelphia, PA, 19104, USA
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Brisbane, QLD, 4102, Australia
| | - Geoffrey Puzon
- CSIRO Land and Water, Private Bag No.5, Wembley, WA, 6913, Australia
| | - Haylea Miller
- CSIRO Land and Water, Private Bag No.5, Wembley, WA, 6913, Australia
| | - Wesaal Khan
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa
| | - Warish Ahmed
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Brisbane, QLD, 4102, Australia.
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Ahmed W, Zhang Q, Ishii S, Hamilton K, Haas C. Microfluidic quantification of multiple enteric and opportunistic bacterial pathogens in roof-harvested rainwater tank samples. ENVIRONMENTAL MONITORING AND ASSESSMENT 2018; 190:105. [PMID: 29383497 DOI: 10.1007/s10661-018-6482-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 01/16/2018] [Indexed: 06/07/2023]
Abstract
Potable and non-potable uses of roof-harvested rainwater (RHRW) are increasing due to water shortages. To protect human health risks, it is important to identify and quantify disease-causing pathogens in RHRW so that appropriate treatment options can be implemented. We used a microfluidic quantitative PCR (MFQPCR) system for the quantitative detection of a wide array of fecal indicator bacteria (FIB) and pathogens in RHRW tank samples along with culturable FIB and conventional qPCR analysis of selected pathogens. Among the nine pathogenic bacteria and their associated genes tested with the MFQPCR, 4.86 and 2.77% samples were positive for Legionella pneumophila and Shigella spp., respectively. The remaining seven pathogens were absent. MFQPCR and conventional qPCR results showed good agreement. Therefore, direct pathogen quantification by MFQPCR systems may be advantageous for circumstances where a thorough microbial analysis is required to assess the public health risks from multiple pathogens that occur simultaneously in the target water source.
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Affiliation(s)
- Warish Ahmed
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Dutton Park, Queensland, 4102, Australia.
| | - Qian Zhang
- BioTechnology Institute, University of Minnesota, Saint Paul, MN, 55108, USA
| | - Satoshi Ishii
- BioTechnology Institute, University of Minnesota, Saint Paul, MN, 55108, USA
| | - Kerry Hamilton
- Drexel University, 3141 Chestnut Street, Philadelphia, PA, 19104, USA
| | - Charles Haas
- Drexel University, 3141 Chestnut Street, Philadelphia, PA, 19104, USA
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Assessment of Water Quality in Roof-Harvested Rainwater Barrels in Greater Philadelphia. WATER 2018. [DOI: 10.3390/w10020092] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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A Review of Roof Harvested Rainwater in Australia. JOURNAL OF ENVIRONMENTAL AND PUBLIC HEALTH 2018; 2018:6471324. [PMID: 29606962 PMCID: PMC5828256 DOI: 10.1155/2018/6471324] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 11/15/2017] [Accepted: 11/20/2017] [Indexed: 12/19/2022]
Abstract
To address concern regarding water sustainability, the Australian Federal Government and many state governments have implemented regulatory mechanisms and incentives to support households to purchase and install rainwater harvesting systems. This has led to an increase in rainwater harvesting in regional and urban Australia. This review examines the implementation of the regulatory mechanisms across Australia. In addition, the literature investigating the potential health consequences of rainwater consumption in Australia was explored. Studies demonstrated that although trace metals such as arsenic, cadmium, chromium, lead, and iron were present in Australian rainwater, these metallic elements were generally found below the health limit guideline, except in high industrial areas. In addition, pathogenic or indicator microorganisms that include, but are not limited to, Escherichia coli, total and faecal coliforms, Campylobacter, Salmonella, Legionella, Pseudomonas, Cryptosporidium, Enterococci, Giardia, Aeromonas, and Mycobacterium avium Complex (MAC) have been detected in rainwater collected in Australia. However, epidemiological evidence suggests that drinking rainwater does not increase the risk of gastrointestinal disease. It was also identified that there is a need for further research investigating the potential for rainwater to be a source of infection for opportunistic pathogens.
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Igbinosa IH, Aighewi IT. Assessment of the Physicochemical and Heavy Metal Qualities of Rooftop Harvested Rainwater in a Rural Community. GLOBAL CHALLENGES (HOBOKEN, NJ) 2017; 1:1700011. [PMID: 31565281 PMCID: PMC6607327 DOI: 10.1002/gch2.201700011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 06/01/2017] [Indexed: 05/08/2023]
Abstract
This study is conducted to assess the quality of harvested rainwater. Rooftop rainwater samples are collected between April and September 2015 from Ugbihioko village near Benin City, Nigeria. Heavy metal concentration and physicochemical quality are determined with the use of standard analytical techniques for water quality, and the results are compared to the World Health Organization (WHO) acceptable limits for drinking water. Of the different water quality parameters, the results show that temperature is within WHO drinking water standards for all locations, but pH, turbidity, sulfate, chloride, and nitrate concentrations vary considerably and do not meet the standards for all locations. Regarding the maximum acceptable concentration (MAC), electrical conductivity is well below the MAC for all cases; the heavy metals copper and iron are above the MAC for all cases; the light metals sodium and potassium are below the MAC for all cases. Lead is above the MAC for all locations, except for in one location; and selenium varied, with some sites having selenium concentrations above the MAC. The results from this study show that public health education or advising is vital for mitigating the possible risks that can be linked to the use of harvested rainwater without treatment.
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Affiliation(s)
- Isoken Henrietta Igbinosa
- Department of Environmental Management and ToxicologyFaculty of Life SciencesUniversity of BeninBenin City300283Nigeria
| | - Isoken Tito Aighewi
- Department of Environmental Management and ToxicologyFaculty of Life SciencesUniversity of BeninBenin City300283Nigeria
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Gikas GD, Tsihrintzis VA. Effect of first-flush device, roofing material, and antecedent dry days on water quality of harvested rainwater. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:21997-22006. [PMID: 28785942 DOI: 10.1007/s11356-017-9868-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Accepted: 07/31/2017] [Indexed: 06/07/2023]
Abstract
Two rainwater harvesting systems, which included first-flush diversion devices, connected to the roofs of two adjacent buildings, were monitored for water quality. The roofs were constructed from different materials, i.e., one roof was covered with ceramic tiles and the other was made of concrete. Water quality samples from the two storage tanks and the first-flush devices were collected and analyzed, showing satisfactory water quality in the tanks for residential non-potable use, while the water in the first-flush device was of poorer quality. Between the two collection surfaces, statistically significant differences were found only in the concentrations of NH4-N, orthophosphate, and Ca2+. Total coliforms were detected in both the storage tanks and the first-flush devices, indicating that disinfection of harvested rainwater may be necessary if it is collected for potable uses. Finally, first-flush water quality was related to antecedent dry days, showing that when the number of dry days increased, the accumulation of materials on the concrete roof was reduced while it was increased on the ceramic tile roof. This is attributed to the fact that the concrete roof is nearly horizontal (very slightly sloped), and the wind action easily removes various materials which accumulate on it.
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Affiliation(s)
- Georgios D Gikas
- Laboratory of Ecological Engineering and Technology, Department of Environmental Engineering, School of Engineering, Democritus University of Thrace, 67100, Xanthi, Greece
| | - Vassilios A Tsihrintzis
- Centre for the Assessment of Natural Hazards and Proactive Planning, & Laboratory of Reclamation Works and Water Resources Management, Department of Infrastructure and Rural Development, School of Rural and Surveying Engineering, National Technical University of Athens, Zografou, 157 80, Athens, Greece.
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Hamilton KA, Ahmed W, Toze S, Haas CN. Human health risks for Legionella and Mycobacterium avium complex (MAC) from potable and non-potable uses of roof-harvested rainwater. WATER RESEARCH 2017; 119:288-303. [PMID: 28500949 DOI: 10.1016/j.watres.2017.04.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 03/30/2017] [Accepted: 04/02/2017] [Indexed: 05/25/2023]
Abstract
A quantitative microbial risk assessment (QMRA) of opportunistic pathogens Legionella pneumophila (LP) and Mycobacterium avium complex (MAC) was undertaken for various uses of roof-harvested rainwater (RHRW) reported in Queensland, Australia to identify appropriate usages and guide risk management practices. Risks from inhalation of aerosols due to showering, swimming in pools topped up with RHRW, use of a garden hose, car washing, and toilet flushing with RHRW were considered for LP while both ingestion (drinking, produce consumption, and accidental ingestion from various activities) and inhalation risks were considered for MAC. The drinking water route of exposure presented the greatest risks due to cervical lymphadenitis and disseminated infection health endpoints for children and immune-compromised populations, respectively. It is therefore not recommended that these populations consume untreated rainwater. LP risks were up to 6 orders of magnitude higher than MAC risks for the inhalation route of exposure for all scenarios. Both inhalation and ingestion QMRA simulations support that while drinking, showering, and garden hosing with RHRW may present the highest risks, car washing and clothes washing could constitute appropriate uses of RHRW for all populations, and toilet flushing and consumption of lettuce irrigation with RHRW would be appropriate for non- immune-compromised populations.
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Affiliation(s)
- Kerry A Hamilton
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Qld 4102, Australia; Drexel University, 3141 Chestnut Street, Philadelphia, PA 19104, USA.
| | - Warish Ahmed
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Qld 4102, Australia
| | - Simon Toze
- CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Qld 4102, Australia
| | - Charles N Haas
- Drexel University, 3141 Chestnut Street, Philadelphia, PA 19104, USA
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Igbinosa IH, Aighewi IT. Quality assessment and public health status of harvested rainwater in a peri-urban community in Edo State of Nigeria. ENVIRONMENTAL MONITORING AND ASSESSMENT 2017; 189:405. [PMID: 28726176 DOI: 10.1007/s10661-017-6122-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 07/10/2017] [Indexed: 06/07/2023]
Abstract
The harvested rainwater is an alternative water source in communities where there is limited or scarcity of water distribution system. However, contamination of roof-harvested rainwater is of immense concern to the general public health. Therefore, this study was initiated to assess the levels of physicochemical quality and heavy metal concentrations in the harvested rainwater from Oluku communities in Benin City, Edo State, Nigeria. The roof-harvested rainwater samples were collected from 20 independent different residential households in Oluku communities, between April 2015 and September 2015. Physicochemical analyses were carried out using standard analytical methods, and heavy metal concentrations were determined using atomic absorption spectrophotometry. The evaluation of the rainwater harvesting shows that 60% (12/20) of the roofs were made of corrugated iron sheets; aluminum sheets, 20% (4/20); asbestos, 10% (2/20); and open space was 10% (2/20). Also, the storage systems used for the storage of harvested rainwater were as follows: PVC tanks, 20% (4/20); drums, 30% (6/20); buckets, 25% (5/20); and wells, 25% (5/20). The physicochemical indicators investigated (temperature, nitrate, chlorine content, electrical conductivity, phosphate, total dissolved solids, and sulfate) were within World Health Organization (WHO) guidelines. However, some pH levels of the roof-harvested rainwater were acidic and below the WHO standard. Furthermore, a high value of turbidity was observed in some locations and exceeded the WHO guidelines. Though some heavy metal indicators (Zn, Na, K, and Ca) in this study were within the WHO guidelines, some locations revealed heavy metal (Cu, Fe, and Cd) concentrations slightly above the WHO guidelines. There is need for proper rainwater harvesting system and continuous monitoring of harvested rainwater for potable uses.
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Affiliation(s)
- Isoken H Igbinosa
- Department of Environmental Management and Toxicology, Faculty of Life Sciences, University of Benin, Private Mail Bag 1154, Benin City, Nigeria.
| | - Isoken T Aighewi
- Department of Environmental Management and Toxicology, Faculty of Life Sciences, University of Benin, Private Mail Bag 1154, Benin City, Nigeria
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Ford L, Bharadwaj L, McLeod L, Waldner C. Human Health Risk Assessment Applied to Rural Populations Dependent on Unregulated Drinking Water Sources: A Scoping Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2017; 14:ijerph14080846. [PMID: 28788087 PMCID: PMC5580550 DOI: 10.3390/ijerph14080846] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 07/15/2017] [Accepted: 07/25/2017] [Indexed: 01/28/2023]
Abstract
Safe drinking water is a global challenge for rural populations dependent on unregulated water. A scoping review of research on human health risk assessments (HHRA) applied to this vulnerable population may be used to improve assessments applied by government and researchers. This review aims to summarize and describe the characteristics of HHRA methods, publications, and current literature gaps of HHRA studies on rural populations dependent on unregulated or unspecified drinking water. Peer-reviewed literature was systematically searched (January 2000 to May 2014) and identified at least one drinking water source as unregulated (21%) or unspecified (79%) in 100 studies. Only 7% of reviewed studies identified a rural community dependent on unregulated drinking water. Source water and hazards most frequently cited included groundwater (67%) and chemical water hazards (82%). Most HHRAs (86%) applied deterministic methods with 14% reporting probabilistic and stochastic methods. Publications increased over time with 57% set in Asia, and 47% of studies identified at least one literature gap in the areas of research, risk management, and community exposure. HHRAs applied to rural populations dependent on unregulated water are poorly represented in the literature even though almost half of the global population is rural.
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Affiliation(s)
- Lorelei Ford
- School of Environment and Sustainability, University of Saskatchewan, 117 Science Place, Saskatoon SK S7N 5C8, Canada.
| | - Lalita Bharadwaj
- School of Public Health, University of Saskatchewan, 107 Wiggins Road, Saskatoon SK S7N 2Z4, Canada.
| | - Lianne McLeod
- Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon SK S7N 5B4, Canada.
| | - Cheryl Waldner
- Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon SK S7N 5B4, Canada.
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Chaudhry RM, Hamilton KA, Haas CN, Nelson KL. Drivers of Microbial Risk for Direct Potable Reuse and de Facto Reuse Treatment Schemes: The Impacts of Source Water Quality and Blending. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2017; 14:E635. [PMID: 28608808 PMCID: PMC5486321 DOI: 10.3390/ijerph14060635] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 06/06/2017] [Accepted: 06/07/2017] [Indexed: 11/16/2022]
Abstract
Although reclaimed water for potable applications has many potential benefits, it poses concerns for chemical and microbial risks to consumers. We present a quantitative microbial risk assessment (QMRA) Monte Carlo framework to compare a de facto water reuse scenario (treated wastewater-impacted surface water) with four hypothetical Direct Potable Reuse (DPR) scenarios for Norovirus, Cryptosporidium, and Salmonella. Consumer microbial risks of surface source water quality (impacted by 0-100% treated wastewater effluent) were assessed. Additionally, we assessed risks for different blending ratios (0-100% surface water blended into advanced-treated DPR water) when source surface water consisted of 50% wastewater effluent. De facto reuse risks exceeded the yearly 10-4 infections risk benchmark while all modeled DPR risks were significantly lower. Contamination with 1% or more wastewater effluent in the source water, and blending 1% or more wastewater-impacted surface water into the advanced-treated DPR water drove the risk closer to the 10-4 benchmark. We demonstrate that de facto reuse by itself, or as an input into DPR, drives microbial risks more so than the advanced-treated DPR water. When applied using location-specific inputs, this framework can contribute to project design and public awareness campaigns to build legitimacy for DPR.
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Affiliation(s)
- Rabia M Chaudhry
- Civil and Environmental Engineering, University of California, Berkeley, CA 94720, USA.
- Engineering Research Center for Re-Inventing the Nation's Urban Water Infrastructure (ReNUWIt), Berkeley, CA 94720-1710, USA.
| | - Kerry A Hamilton
- Drexel University Department of Civil, Architectural, and Environmental Engineering, 3141 Chestnut Street, Philadelphia, PA 19104, USA.
| | - Charles N Haas
- Drexel University Department of Civil, Architectural, and Environmental Engineering, 3141 Chestnut Street, Philadelphia, PA 19104, USA.
| | - Kara L Nelson
- Civil and Environmental Engineering, University of California, Berkeley, CA 94720, USA.
- Engineering Research Center for Re-Inventing the Nation's Urban Water Infrastructure (ReNUWIt), Berkeley, CA 94720-1710, USA.
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Hamilton KA, Ahmed W, Palmer A, Smith K, Toze S, Haas CN. Seasonal Assessment of Opportunistic Premise Plumbing Pathogens in Roof-Harvested Rainwater Tanks. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:1742-1753. [PMID: 28040888 DOI: 10.1021/acs.est.6b04814] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A seasonal study on the occurrence of six opportunistic premise plumbing pathogens (OPPPs) in 24 roof-harvested rainwater (RHRW) tanks repeatedly sampled over six monthly sampling events (n = 144) from August 2015 to March 2016 was conducted using quantitative qPCR. Fecal indicator bacteria (FIB) Escherichia coli (E. coli) and Enterococcus spp. were enumerated using culture-based methods. All tank water samples over the six events were positive for at least one OPPP (Legionella spp., Legionella pneumophila, Mycobacterium avium, Mycobacterium intracellulare, Pseudmonas aeruginosa, or Acanthamoeba spp.) during the entire course of the study. FIB were positively but weakly correlated with P. aeruginosa (E. coli vs P. aeruginosa τ = 0.090, p = 0.027; Enterococcus spp. vs P. aeruginosa τ = 0.126, p = 0.002), but not the other OPPPs. FIBs were more prevalent during the wet season than the dry season, and L. pneumophila was only observed during the wet season. However, concentrations of Legionella spp., M. intracellulare, Acanthamoeba spp., and M. avium peaked during the dry season. Correlations were assessed between FIB and OPPPs with meteorological variables, and it was determined that P. aeruginosa was the only OPPP positively associated with an increased antecedent dry period, suggesting stagnation time may play a role for the occurrence of this OPPP in tank water. Infection risks may exceed commonly cited benchmarks for uses reported in the rainwater usage survey such as pool top-up, and warrant further exploration through quantitative microbial risk assessment (QMRA).
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Affiliation(s)
- Kerry A Hamilton
- CSIRO Land and Water , Ecosciences Precinct, 41 Boggo Road, Dutton Park, Queensland 4102, Australia
- Drexel University , 3141 Chestnut Street, Philadelphia, Pennsylvania 19104, United States
| | - Warish Ahmed
- CSIRO Land and Water , Ecosciences Precinct, 41 Boggo Road, Dutton Park, Queensland 4102, Australia
| | - Andrew Palmer
- CSIRO Land and Water , Ecosciences Precinct, 41 Boggo Road, Dutton Park, Queensland 4102, Australia
| | - Kylie Smith
- CSIRO Land and Water , Ecosciences Precinct, 41 Boggo Road, Dutton Park, Queensland 4102, Australia
| | - Simon Toze
- CSIRO Land and Water , Ecosciences Precinct, 41 Boggo Road, Dutton Park, Queensland 4102, Australia
| | - Charles N Haas
- Drexel University , 3141 Chestnut Street, Philadelphia, Pennsylvania 19104, United States
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Schoen ME, Ashbolt NJ, Jahne MA, Garland J. Risk-based enteric pathogen reduction targets for non-potable and direct potable use of roof runoff, stormwater, and greywater. MICROBIAL RISK ANALYSIS 2017; 5:32-43. [PMID: 31534999 PMCID: PMC6750756 DOI: 10.1016/j.mran.2017.01.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
This paper presents risk-based enteric pathogen log reduction targets for non-potable and potable uses of a variety of alternative source waters (i.e., locally-collected greywater, roof runoff, and stormwater). A probabilistic Quantitative Microbial Risk Assessment (QMRA) was used to derive the pathogen log10 reduction targets (LRTs) that corresponded with an infection risk of either 10-4 per person per year (ppy) or 10-2 ppy. The QMRA accounted for variation in pathogen concentration and sporadic pathogen occurrence (when data were available) in source waters for reference pathogens in the genera Rotavirus, Mastadenovirus(human adenoviruses), Norovirus, Campylobacter, Salmonella, Giardia and Cryptosporidium. Non-potable uses included indoor use (for toilet flushing and clothes washing) with occasional accidental ingestion of treated non-potable water (or cross-connection with potable water), and unrestricted irrigation for outdoor use. Various exposure scenarios captured the uncertainty from key inputs, i.e., the pathogen concentration in source water; the volume of water ingested; and for the indoor use, the frequency of and the fraction of the population exposed to accidental ingestion. Both potable and non-potable uses required pathogen treatment for the selected waters and the LRT was generally greater for potable use than non-potable indoor use and unrestricted irrigation. The difference in treatment requirements among source waters was driven by the microbial quality of the water - both the density and occurrence of reference pathogens. Greywater from collection systems with 1000 people had the highest LRTs; however, those for greywater collected from a smaller population (~ 5 people), which have less frequent pathogen occurrences, were lower. Stormwater had highly variable microbial quality, which resulted in a range of possible treatment requirements. The microbial quality of roof runoff, and thus the resulting LRTs, remains uncertain due to lack of relevant pathogen data.
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Affiliation(s)
- Mary E Schoen
- Soller Environmental, Inc., 3022 King St., Berkeley, CA 94703, USA
| | - Nicholas J Ashbolt
- Rm. 3-57D South Academic Building, School of Public Health, University of Alberta, Edmonton AB T6G 2G7, Canada
| | - Michael A Jahne
- U.S. Environmental Protection Agency, 26 W. Martin Luther King Drive, Cincinnati OH 45268, USA
| | - Jay Garland
- U.S. Environmental Protection Agency, 26 W. Martin Luther King Drive, Cincinnati OH 45268, USA
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Strauss A, Dobrowsky PH, Ndlovu T, Reyneke B, Khan W. Comparative analysis of solar pasteurization versus solar disinfection for the treatment of harvested rainwater. BMC Microbiol 2016; 16:289. [PMID: 27938342 PMCID: PMC5148859 DOI: 10.1186/s12866-016-0909-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 12/06/2016] [Indexed: 12/20/2022] Open
Abstract
Background Numerous pathogens and opportunistic pathogens have been detected in harvested rainwater. Developing countries, in particular, require time- and cost-effective treatment strategies to improve the quality of this water source. The primary aim of the current study was thus to compare solar pasteurization (SOPAS; 70 to 79 °C; 80 to 89 °C; and ≥90 °C) to solar disinfection (SODIS; 6 and 8 hrs) for their efficiency in reducing the level of microbial contamination in harvested rainwater. The chemical quality (anions and cations) of the SOPAS and SODIS treated and untreated rainwater samples were also monitored. Results While the anion concentrations in all the samples were within drinking water guidelines, the concentrations of lead (Pb) and nickel (Ni) exceeded the guidelines in all the SOPAS samples. Additionally, the iron (Fe) concentrations in both the SODIS 6 and 8 hr samples were above the drinking water guidelines. A >99% reduction in Escherichia coli and heterotrophic bacteria counts was then obtained in the SOPAS and SODIS samples. Ethidium monoazide bromide quantitative polymerase chain reaction (EMA-qPCR) analysis revealed a 94.70% reduction in viable Legionella copy numbers in the SOPAS samples, while SODIS after 6 and 8 hrs yielded a 50.60% and 75.22% decrease, respectively. Similarly, a 99.61% reduction in viable Pseudomonas copy numbers was observed after SOPAS treatment, while SODIS after 6 and 8 hrs yielded a 47.27% and 58.31% decrease, respectively. Conclusion While both the SOPAS and SODIS systems reduced the indicator counts to below the detection limit, EMA-qPCR analysis indicated that SOPAS treatment yielded a 2- and 3-log reduction in viable Legionella and Pseudomonas copy numbers, respectively. Additionally, SODIS after 8 hrs yielded a 2-log and 1-log reduction in Legionella and Pseudomonas copy numbers, respectively and could be considered as an alternative, cost-effective treatment method for harvested rainwater.
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Affiliation(s)
- André Strauss
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa
| | - Penelope Heather Dobrowsky
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa
| | - Thando Ndlovu
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa
| | - Brandon Reyneke
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa
| | - Wesaal Khan
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch, 7602, South Africa.
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45
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Reyneke B, Dobrowsky PH, Ndlovu T, Khan S, Khan W. EMA-qPCR to monitor the efficiency of a closed-coupled solar pasteurization system in reducing Legionella contamination of roof-harvested rainwater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 553:662-670. [PMID: 26990076 DOI: 10.1016/j.scitotenv.2016.02.108] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 02/12/2016] [Accepted: 02/15/2016] [Indexed: 06/05/2023]
Abstract
Solar pasteurization is effective in reducing the level of indicator organisms in stored rainwater to within drinking water standards. However, Legionella spp. were detected at temperatures exceeding the recommended pasteurization temperatures using polymerase chain reaction assays. The aim of the current study was thus to apply EMA quantitative polymerase chain reaction (EMA-qPCR) to determine whether the Legionella spp. detected were intact cells and therefore possibly viable at pasteurization temperatures >70°C. The BacTiter-Glo™ Microbial Cell Viability Assay was also used to detect the presence of ATP in the tested samples, as ATP indicates the presence of metabolically active cells. Chemical analysis also indicated that all anions and cations were within the respective drinking water guidelines, with the exception of iron (mean: 186.76 μg/L) and aluminium (mean: 188.13 μg/L), which were detected in the pasteurized tank water samples at levels exceeding recommended guidelines. The BacTiter-Glo™ Microbial Cell Viability Assay indicated the presence of viable cells for all pasteurized temperatures tested, with the percentage of ATP (in the form of relative light units) decreasing with increasing temperature [70-79°C (96.7%); 80- 89°C (99.2%); 90-95°C (99.7%)]. EMA-qPCR then indicated that while solar pasteurization significantly reduced (p<0.05) the genomic copy numbers of intact Legionella cells in the pasteurized tank water (~99%), no significant difference (p>0.05) in the mean copy numbers was detected with an increase in the pasteurization temperature, with 6 × 10(3) genomic copies/mL DNA sample obtained at 95°C. As intact Legionella cells were detected in the pasteurized tank water samples, quantitative microbial risk assessment studies need to be conducted to determine the potential health risk associated with using the water for domestic purposes.
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Affiliation(s)
- B Reyneke
- Department of Microbiology, Faculty of Science, University of Stellenbosch, Private Bag X1, Stellenbosch 7602, South Africa
| | - P H Dobrowsky
- Department of Microbiology, Faculty of Science, University of Stellenbosch, Private Bag X1, Stellenbosch 7602, South Africa
| | - T Ndlovu
- Department of Microbiology, Faculty of Science, University of Stellenbosch, Private Bag X1, Stellenbosch 7602, South Africa
| | - S Khan
- Department of Biomedical Sciences, Faculty of Health and Wellness Sciences, Cape Peninsula University of Technology, P.O. Box 1906, Bellville 7535, South Africa
| | - W Khan
- Department of Microbiology, Faculty of Science, University of Stellenbosch, Private Bag X1, Stellenbosch 7602, South Africa.
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46
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Rainwater Harvesting Typologies for UK Houses: A Multi Criteria Analysis of System Configurations. WATER 2016. [DOI: 10.3390/w8040129] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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47
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Nygren BL, O'Reilly CE, Rajasingham A, Omore R, Ombok M, Awuor AO, Jaron P, Moke F, Vulule J, Laserson K, Farag TH, Nasrin D, Nataro JP, Kotloff KL, Levine MM, Derado G, Ayers TL, Lash RR, Breiman RF, Mintz ED. The Relationship Between Distance to Water Source and Moderate-to-Severe Diarrhea in the Global Enterics Multi-Center Study in Kenya, 2008-2011. Am J Trop Med Hyg 2016; 94:1143-9. [PMID: 26928833 DOI: 10.4269/ajtmh.15-0393] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 01/21/2016] [Indexed: 11/07/2022] Open
Abstract
In the developing world, fetching water for drinking and other household uses is a substantial burden that affects water quantity and quality in the household. We used logistic regression to examine whether reported household water fetching times were a risk factor for moderate-to-severe diarrhea (MSD) using case-control data of 3,359 households from the Global Enterics Multi-Center Study in Kenya in 2009-2011. We collected additional global positioning system (GPS) data for a subset of 254 randomly selected households and compared GPS-based straight line and actual travel path distances to fetching times reported by respondents. GPS-based data were highly correlated with respondent-provided times (Spearman correlation coefficient = 0.81, P < 0.0001). The median estimated one-way distance to water source was 200 m for cases and 171 for controls (Wilcoxon rank sums/Mann-Whitney P = 0.21). A round-trip fetching time of > 30 minutes was reported by 25% of cases versus 15% of controls and was significantly associated with MSD where rainwater was not used in the last 2 weeks (odds ratio = 1.97, 95% confidence interval = 1.56-2.49). These data support the United Nations definition of access to an improved water source being within 30 minutes total round-trip travel time.
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Affiliation(s)
- Benjamin L Nygren
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Ciara E O'Reilly
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Anangu Rajasingham
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Richard Omore
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Maurice Ombok
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Alex O Awuor
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Peter Jaron
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Fenny Moke
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - John Vulule
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Kayla Laserson
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Tamer H Farag
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Dilruba Nasrin
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - James P Nataro
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Karen L Kotloff
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Myron M Levine
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Gordana Derado
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Tracy L Ayers
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - R Ryan Lash
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Robert F Breiman
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Eric D Mintz
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya; Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya; Center for Vaccine Development, School of Medicine, University of Maryland, Baltimore, Maryland; Centers for Disease Control and Prevention, Nairobi, Kenya
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48
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Stephen DM, Barnett AG. Effect of temperature and precipitation on salmonellosis cases in South-East Queensland, Australia: an observational study. BMJ Open 2016; 6:e010204. [PMID: 26916693 PMCID: PMC4769393 DOI: 10.1136/bmjopen-2015-010204] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE Foodborne illnesses in Australia, including salmonellosis, are estimated to cost over $A1.25 billion annually. The weather has been identified as being influential on salmonellosis incidence, as cases increase during summer, however time series modelling of salmonellosis is challenging because outbreaks cause strong autocorrelation. This study assesses whether switching models is an improved method of estimating weather-salmonellosis associations. DESIGN We analysed weather and salmonellosis in South-East Queensland between 2004 and 2013 using 2 common regression models and a switching model, each with 21-day lags for temperature and precipitation. RESULTS The switching model best fit the data, as judged by its substantial improvement in deviance information criterion over the regression models, less autocorrelated residuals and control of seasonality. The switching model estimated a 5 °C increase in mean temperature and 10 mm precipitation were associated with increases in salmonellosis cases of 45.4% (95% CrI 40.4%, 50.5%) and 24.1% (95% CrI 17.0%, 31.6%), respectively. CONCLUSIONS Switching models improve on traditional time series models in quantifying weather-salmonellosis associations. A better understanding of how temperature and precipitation influence salmonellosis may identify where interventions can be made to lower the health and economic costs of salmonellosis.
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Affiliation(s)
- Dimity Maree Stephen
- Institute of Health and Biomedical Innovation, School of Public Health and Social Work, Queensland University of Technology, Kelvin Grove, Queensland, Australia
| | - Adrian Gerard Barnett
- Institute of Health and Biomedical Innovation, School of Public Health and Social Work, Queensland University of Technology, Kelvin Grove, Queensland, Australia
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49
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Lu J, Struewing I, Vereen E, Kirby AE, Levy K, Moe C, Ashbolt N. Molecular Detection of Legionella
spp. and their associations with Mycobacterium
spp., Pseudomonas aeruginosa
and amoeba hosts in a drinking water distribution system. J Appl Microbiol 2016; 120:509-21. [DOI: 10.1111/jam.12996] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 10/08/2015] [Accepted: 10/27/2015] [Indexed: 01/12/2023]
Affiliation(s)
- J. Lu
- U.S. EPA National Exposure Research Laboratory; Cincinnati OH USA
| | | | - E. Vereen
- Center for Global Safe Water; Sanitation and Hygiene; Emory University; Atlanta GA USA
| | - A. E. Kirby
- Center for Global Safe Water; Sanitation and Hygiene; Emory University; Atlanta GA USA
| | - K. Levy
- Center for Global Safe Water; Sanitation and Hygiene; Emory University; Atlanta GA USA
| | - C. Moe
- Center for Global Safe Water; Sanitation and Hygiene; Emory University; Atlanta GA USA
| | - N. Ashbolt
- School of Public Health; University of Alberta; Edmonton AB Canada
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50
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Church J, Verbyla ME, Lee WH, Randall AA, Amundsen TJ, Zastrow DJ. Dishwashing water recycling system and related water quality standards for military use. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 529:275-284. [PMID: 26025638 DOI: 10.1016/j.scitotenv.2015.05.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 04/29/2015] [Accepted: 05/03/2015] [Indexed: 06/04/2023]
Abstract
As the demand for reliable and safe water supplies increases, both water quality and available quantity are being challenged by population growth and climate change. Greywater reuse is becoming a common practice worldwide; however, in remote locations of limited water supply, such as those encountered in military installations, it is desirable to expand its classification to include dishwashing water to maximize the conservation of fresh water. Given that no standards for dishwashing greywater reuse by the military are currently available, the current study determined a specific set of water quality standards for dishwater recycling systems for U.S. military field operations. A tentative water reuse standard for dishwashing water was developed based on federal and state regulations and guidelines for non-potable water, and the developed standard was cross-evaluated by monitoring water quality data from a full-scale dishwashing water recycling system using an innovative electrocoagulation and ultrafiltration process. Quantitative microbial risk assessment (QMRA) was also performed based on exposure scenarios derived from literature data. As a result, a specific set of dishwashing water reuse standards for field analysis (simple, but accurate) was finalized as follows: turbidity (<1 NTU), Escherichia coli (<50 cfu mL(-1)), and pH (6-9). UV254 was recommended as a surrogate for organic contaminants (e.g., BOD5), but requires further calibration steps for validation. The developed specific water standard is the first for dishwashing water reuse and will be expected to ensure that water quality is safe for field operations, but not so stringent that design complexity, cost, and operational and maintenance requirements will not be feasible for field use. In addition the parameters can be monitored using simple equipment in a field setting with only modest training requirements and real-time or rapid sample turn-around. This standard may prove useful in future development of civilian guidelines.
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Affiliation(s)
- Jared Church
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL, USA
| | - Matthew E Verbyla
- Department of Civil and Environmental Engineering, University of South Florida, Tampa, FL, USA
| | - Woo Hyoung Lee
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL, USA.
| | - Andrew A Randall
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL, USA
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