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Dowdell KS, Potgieter SC, Olsen K, Lee S, Vedrin M, Caverly LJ, LiPuma JJ, Raskin L. Source-to-tap investigation of the occurrence of nontuberculous mycobacteria in a full-scale chloraminated drinking water system. Appl Environ Microbiol 2024; 90:e0060924. [PMID: 39109876 PMCID: PMC11409651 DOI: 10.1128/aem.00609-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Accepted: 07/08/2024] [Indexed: 09/19/2024] Open
Abstract
Nontuberculous mycobacteria (NTM) in drinking water are a significant public health concern. However, an incomplete understanding of the factors that influence the occurrence of NTM in drinking water limits our ability to characterize risk and prevent infection. This study sought to evaluate the influence of season and water treatment, distribution, and stagnation on NTM in drinking water. Samples were collected source-to-tap in a full-scale, chloraminated drinking water system approximately monthly from December 2019 to November 2020. NTM were characterized using culture-dependent (plate culture with matrix-assisted laser desorption ionization-time-of-flight mass spectrometry [MALDI-TOF MS] isolate analysis) and culture-independent methods (quantitative PCR and genome-resolved metagenomics). Sampling locations included source waters, three locations within the treatment plant, and five buildings receiving water from the distribution system. Building plumbing samples consisted of first draw, 5-min flush, and full flush cold-water samples. As the study took place during the COVID-19 pandemic, the influence of reduced water usage in three of the five buildings was also investigated. The highest NTM densities source-to-tap were found in the summer first draw building water samples (107 gene copies/L), which also had the lowest monochloramine concentrations. Flushing was found to be effective for reducing NTM and restoring disinfectant residuals, though flush times necessary to improve water quality varied by building. Clinically relevant NTM species, including Mycobacterium avium, were recovered via plate culture, with increased occurrence observed in buildings with higher water age. Four of five NTM metagenome-assembled genomes were identified to the species level and matched identified isolates.IMPORTANCENTM infections are increasing in prevalence, difficult to treat, and associated with high morbidity and mortality rates. Our lack of understanding of the factors that influence NTM occurrence in drinking water limits our ability to prevent infections, accurately characterize risk, and focus remediation efforts. In this study, we comprehensively evaluated NTM in a full-scale drinking water system, showing that various steps in treatment and distribution influence NTM presence. Stagnant building water contained the highest NTM densities source-to-tap and was associated with low disinfectant residuals. We illustrated the differences in NTM detection and characterization obtained from culture-based and culture-independent methods, highlighting the complementarity between these approaches. We demonstrated that focusing NTM mitigation efforts in building plumbing systems, which have the highest NTM densities source-to-tap, has potential for immediate positive effects. We also identified steps during treatment that increase NTM levels, which provides beneficial information for utilities seeking to reduce NTM in finished water.
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Affiliation(s)
- Katherine S Dowdell
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Sarah C Potgieter
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Kirk Olsen
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Soojung Lee
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Matthew Vedrin
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Lindsay J Caverly
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - John J LiPuma
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Lutgarde Raskin
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, Michigan, USA
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2
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Lee-Masi M, Coulter C, Chow SJ, Zaitchik B, Jacangelo JG, Exum NG, Schwab KJ. Two-year evaluation of Legionella in an aging residential building: Assessment of multiple potable water remediation approaches. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 941:173710. [PMID: 38830423 PMCID: PMC11238177 DOI: 10.1016/j.scitotenv.2024.173710] [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: 02/23/2024] [Revised: 05/30/2024] [Accepted: 05/31/2024] [Indexed: 06/05/2024]
Abstract
Legionella is an opportunistic waterborne pathogen that is difficult to eradicate in colonized drinking water pipes. Legionella control is further challenged by aging water infrastructure and lack of evidence-based guidance for building treatment. This study assessed multiple premise water remediation approaches designed to reduce Legionella pneumophila within a residential building located in an aging, urban drinking water system over a two-year period. Samples (n = 745) were collected from hot and cold-water lines and quantified via most probable number culture. Building-level treatment approaches included three single heat shocks, three single chemical shocks, and continuous low-level chemical disinfection in the potable water system. The building was highly colonized with L. pneumophila with 71 % L. pneumophila positivity. Single heat shocks had a statistically significant L. pneumophila reduction one day post treatment but no significant L. pneumophila reduction at one week, two weeks, and four weeks post treatment. The first two chemical shocks resulted in statistically significant L. pneumophila reduction at two days and four weeks post treatment, but there was a significant L. pneumophila increase at four weeks following the third chemical shock. Continuous low-level chemical disinfection resulted in statistically significant L. pneumophila reduction at ten weeks post treatment implementation. This demonstrates that in a building highly colonized with L. pneumophila, sustained remediation is best achieved using continuous low-level chemical treatment.
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Affiliation(s)
- Monica Lee-Masi
- Department of Environmental Health & Engineering, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe St, Baltimore, MD 21205, United States
| | - Caroline Coulter
- Department of Environmental Health & Engineering, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe St, Baltimore, MD 21205, United States
| | - Steven J Chow
- Department of Environmental Health & Engineering, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe St, Baltimore, MD 21205, United States
| | - Benjamin Zaitchik
- Department of Earth and Planetary Sciences, Johns Hopkins Krieger School of Arts and Sciences, 3400 N. Charles St., Baltimore, MD 21218, United States
| | - Joseph G Jacangelo
- Department of Environmental Health & Engineering, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe St, Baltimore, MD 21205, United States; Stantec, 1299 Pennsylvania Ave. NW Ste 405, Washington, DC 20004, United States
| | - Natalie G Exum
- Department of Environmental Health & Engineering, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe St, Baltimore, MD 21205, United States
| | - Kellogg J Schwab
- Department of Environmental Health & Engineering, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe St, Baltimore, MD 21205, United States.
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3
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Lippai A, Ágoston C, Szunyogh L. The impact of stagnation on the microbial quality of constructed water systems after COVID-19 shutdowns. Biol Futur 2024:10.1007/s42977-024-00231-5. [PMID: 39048893 DOI: 10.1007/s42977-024-00231-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 07/14/2024] [Indexed: 07/27/2024]
Abstract
In response to COVID-19 pandemic, governments all over the world limited the movement of people and mandated temporary closure of different institutions. While, these measures helped to reduce the spread of COVID-19, stagnant water can cause water quality deterioration. Stagnation is considered in context with the proliferation of pathogenic and facultatively pathogenic bacteria which pose potential health risks to humans. The objective of this study was to document the hygienic microbiological status of different water systems after the first shutdowns (between 18th March 2020 and 18th May 2020) in Hungary in comparison with a reference period (between 3rd January 2020 to 17th March). During the reference period drinking waters were compliant > 95% of total samples to the parametric values. After the short period shutdowns, the ratio of tnon-compliant drinking water samples was 6.6%: mainly Pseudomonas aeruginosa (7%) and coliform bacteria (5%) resulted poor water quality. The microscopic analysis of drinking waters showed that after low water demand the values of non-compliant samples also increased due to the proliferation of Amoebozoa and other Protozoa species. The compliant pool waters' ratio was also high in the reference period (97-99%), while after the shutdowns more samples were positive in both pool operation type (fill-and-drain pools and pools with recirculation) due to the proliferation of P. aeruginosa (14%) and micrococci (12%). Legionella non-compliant samples in hot tap water did not show significant difference during both studied periods (15%) although after stagnation the Legionella CFU (colony forming unit) values of the samples increased markedly.
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Affiliation(s)
- Anett Lippai
- Biokör Technology and Environmental Protection Ltd., Bláthy Ottó utca 41., Budapest, 1089, Hungary.
| | - Csaba Ágoston
- Biokör Technology and Environmental Protection Ltd., Bláthy Ottó utca 41., Budapest, 1089, Hungary
| | - Lilla Szunyogh
- Budapest Spas cPlc., Orlay utca 5-7., Budapest, 1117, Hungary
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4
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Nisar MA, Ross KE, Brown MH, Bentham R, Best G, Eyre NS, Leterme SC, Whiley H. Increased flushing frequency of a model plumbing system initially promoted the formation of viable but non culturable cells but ultimately reduced the concentration of culturable and total Legionella DNA. Heliyon 2024; 10:e32334. [PMID: 38933949 PMCID: PMC11200333 DOI: 10.1016/j.heliyon.2024.e32334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 05/30/2024] [Accepted: 06/02/2024] [Indexed: 06/28/2024] Open
Abstract
Legionella is the causative agent of Legionnaires' disease, and its prevalence in potable water is a significant public health issue. Water stagnation within buildings increases the risk of Legionella. However, there are limited studies investigating how stagnation arising through intermittent usage affects Legionella proliferation and the studies that are available do not consider viable but non culturable (VBNC) Legionella. This study used a model plumbing system to examine how intermittent water stagnation affects both VBNC and culturable Legionella. The model plumbing system contained a water tank supplying two biofilm reactors. The model was initially left stagnant for ≈5 months (147 days), after which one reactor was flushed daily, and the other weekly. Biofilm coupons, and water samples were collected for analysis at days 0, 14 and 28. These samples were analysed for culturable and VBNC Legionella, free-living amoebae, and heterotrophic bacteria. After 28 days, once-a-day flushing significantly (p < 0.001) reduced the amount of biofilm-associated culturable Legionella (1.5 log10 reduction) compared with weekly flushing. However, higher counts of biofilm-associated VBNC Legionella (1 log10 higher) were recovered from the reactor with once-a-day flushing compared with weekly flushing. Likewise, once-a-day flushing increased the population of biofilm-associated Vermamoeba vermiformis (approximately 3 log10 higher) compared with weekly flushing, which indicated a positive relationship between VBNC Legionella and V. vermiformis. This is the first study to investigate the influence of stagnation on VBNC Legionella under environmental conditions. Overall, this study showed that a reduction in water stagnation decreased culturable Legionella but not VBNC Legionella.
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Affiliation(s)
- Muhammad Atif Nisar
- College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
| | - Kirstin E. Ross
- College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
| | - Melissa H. Brown
- College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
- ARC Training Centre for Biofilm Research and Innovation, Flinders University, Bedford Park, SA, 5042, Australia
| | - Richard Bentham
- College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
| | - Giles Best
- College of Medicine and Public Health, Flinders University, Bedford Park, SA, 5042, Australia
- Flow Cytometry Facility, Flinders University, Bedford Park, SA, 5042, Australia
| | - Nicholas S. Eyre
- College of Medicine and Public Health, Flinders University, Bedford Park, SA, 5042, Australia
| | - Sophie C. Leterme
- College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
- ARC Training Centre for Biofilm Research and Innovation, Flinders University, Bedford Park, SA, 5042, Australia
- Institute for Nanoscience and Technology, Flinders University, Bedford Park, SA, 5042, Australia
| | - Harriet Whiley
- College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
- ARC Training Centre for Biofilm Research and Innovation, Flinders University, Bedford Park, SA, 5042, Australia
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5
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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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6
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Joshi S, Richard R, Hogue D, Brown J, Cahill M, Kotta V, Call K, Butzine N, Marcos-Hernández M, Alja'fari J, Voth-Gaeddert L, Boyer T, Hamilton KA. Water Quality Trade-offs for Risk Management Interventions in a Green Building. ENVIRONMENTAL SCIENCE : WATER RESEARCH & TECHNOLOGY 2024; 10:767-786. [PMID: 39185481 PMCID: PMC11343562 DOI: 10.1039/d3ew00650f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/27/2024]
Abstract
Premise plumbing water quality degradation has led to negative health impacts from pathogen outbreaks (e.g., Legionella pneumophila and non-tuberculous mycobacteria), as well as chronic effects from exposure to heavy metals or disinfection by-products (DBP). Common water quality management interventions include flushing, heat shock (thermal disinfection), supplemental disinfection (shock or super chlorination), and water heater temperature setpoint change. In this study, a Legionella pneumophila- colonized Leadership in Energy and Environmental Design (LEED) certified building was monitored to study health-relevant water quality changes before and after three controlled management interventions: (1) flushing at several points throughout the building; (2) changing the water heater set point; and (3) a combination of interventions (1) and (2) by flushing during a period of elevated water heater set point (incompletely performed due to operational issues). Microbial (culturable L. pneumophila, the L. pneumophila mip gene, and cATP) and physico-chemical (pH, temperature, conductivity, disinfectant residual, disinfection by-products (DBPs; total trihalomethanes, TTHM), and heavy metals) water quality were monitored alongside building occupancy as approximated using Wi-Fi logins. Flushing alone resulted in a significant decrease in cATP and L. pneumophila concentrations (p = 0.018 and 0.019, respectively) and a significant increase in chlorine concentrations (p = 0.002) as well as iron and DBP levels (p = 0.002). Copper concentrations increased during the water heater temperature setpoint increase alone to 140°F during December 2022 (p = 0.01). During the flushing and elevated temperature in parts of the building in February 2023, there was a significant increase in chlorine concentrations (p = 0.002) and iron (p = 0.002) but no significant decrease in L. pneumophila concentrations in the drinking water samples (p = 0.27). This study demonstrated the potential impacts of short term or incompletely implemented interventions which in this case were not sufficient to holistically improve water quality. As implementing interventions is logistically- and time-intensive, more effective and holistic approaches are needed for informing preventative and corrective actions that are beneficial for multiple water quality and sustainability goals.
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Affiliation(s)
- Sayalee Joshi
- The School of Sustainable Engineering and the Built Environment, Arizona State University, 660S College Ave, Tempe, AZ 85281, USA
- The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, 1001 S McAlister Ave, Tempe, AZ 85281, USA
| | - Rain Richard
- NCS Engineering, 202 E. Earll Drive Suite 110, Phoenix AZ 85012, USA
| | - Derek Hogue
- The School of Sustainable Engineering and the Built Environment, Arizona State University, 660S College Ave, Tempe, AZ 85281, USA
| | - James Brown
- The School of Sustainable Engineering and the Built Environment, Arizona State University, 660S College Ave, Tempe, AZ 85281, USA
| | - Molly Cahill
- The School of Sustainable Engineering and the Built Environment, Arizona State University, 660S College Ave, Tempe, AZ 85281, USA
- The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, 1001 S McAlister Ave, Tempe, AZ 85281, USA
| | - Vishnu Kotta
- The School of Sustainable Engineering and the Built Environment, Arizona State University, 660S College Ave, Tempe, AZ 85281, USA
- The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, 1001 S McAlister Ave, Tempe, AZ 85281, USA
| | - Kathryn Call
- The School of Sustainable Engineering and the Built Environment, Arizona State University, 660S College Ave, Tempe, AZ 85281, USA
| | - Noah Butzine
- The School of Sustainable Engineering and the Built Environment, Arizona State University, 660S College Ave, Tempe, AZ 85281, USA
- The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, 1001 S McAlister Ave, Tempe, AZ 85281, USA
| | - Mariana Marcos-Hernández
- The School of Sustainable Engineering and the Built Environment, Arizona State University, 660S College Ave, Tempe, AZ 85281, USA
- Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ, 85287-3005, USA
| | - Jumana Alja'fari
- The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, 1001 S McAlister Ave, Tempe, AZ 85281, USA
| | - Lee Voth-Gaeddert
- The Biodesign Institute Center for Health Through Microbiomes, Arizona State University, 1001 S McAlister Ave, Tempe, AZ 85281, USA
| | - Treavor Boyer
- The School of Sustainable Engineering and the Built Environment, Arizona State University, 660S College Ave, Tempe, AZ 85281, USA
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, PO Box 873005, Tempe, AZ 85287-3005, USA
| | - Kerry A Hamilton
- The School of Sustainable Engineering and the Built Environment, Arizona State University, 660S College Ave, Tempe, AZ 85281, USA
- The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, 1001 S McAlister Ave, Tempe, AZ 85281, USA
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7
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Ra K, Proctor C, Ley C, Angert D, Noh Y, Odimayomi T, Whelton AJ. Four buildings and a flush: Lessons from degraded water quality and recommendations on building water management. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2024; 18:100314. [PMID: 37854462 PMCID: PMC10579424 DOI: 10.1016/j.ese.2023.100314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 09/07/2023] [Accepted: 09/11/2023] [Indexed: 10/20/2023]
Abstract
A reduction in building occupancy can lead to stagnant water in plumbing, and the potential consequences for water quality have gained increasing attention. To investigate this, a study was conducted during the COVID-19 pandemic, focusing on water quality in four institutional buildings. Two of these buildings were old (>58 years) and large (>19,000 m2), while the other two were new (>13 years) and small (<11,000 m2). The study revealed significant decreases in water usage in the small buildings, whereas usage remained unchanged in the large buildings. Initial analysis found that residual chlorine was rarely detectable in cold/drinking water samples. Furthermore, the pH, dissolved oxygen, total organic carbon, and total cell count levels in the first draw of cold water samples were similar across all buildings. However, the ranges of heavy metal concentrations in large buildings were greater than observed in small buildings. Copper (Cu), lead (Pb), and manganese (Mn) sporadically exceeded drinking water limits at cold water fixtures, with maximum concentrations of 2.7 mg Cu L-1, 45.4 μg Pb L-1, 1.9 mg Mn L-1. Flushing the plumbing for 5 min resulted in detectable residual at fixtures in three buildings, but even after 125 min of flushing in largest and oldest building, no residual chlorine was detected at the fixture closest to the building's point of entry. During the pandemic, the building owner conducted fixture flushing, where one to a few fixtures were operated per visit in buildings with hundreds of fixtures and multiple floors. However, further research is needed to understand the fundamental processes that control faucet water quality from the service line to the faucet. In the absence of this knowledge, building owners should create and use as-built drawings to develop flushing plans and conduct periodic water testing.
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Affiliation(s)
- Kyungyeon Ra
- Lyles School of Civil Engineering, Purdue University, 550 Stadium Mall Drive, West Lafayette, IN, 47907, USA
| | - Caitlin Proctor
- Agricultural and Biological Engineering, Division of Environmental and Ecological Engineering, Purdue University, West Lafayette, IN, 47907, USA
| | - Christian Ley
- Division of Environmental and Ecological Engineering, Purdue University, West Lafayette, IN, 47907, USA
- Civil and Environmental Engineering, University of Colorado, 1111 Engineering Drive, Boulder, CO, 80309, USA
| | - Danielle Angert
- Division of Environmental and Ecological Engineering, Purdue University, West Lafayette, IN, 47907, USA
- Civil, Architectural and Environmental Engineering, University of Texas, 301E E Dean Keeton Street, Austin, TX, 78712, USA
| | - Yoorae Noh
- Lyles School of Civil Engineering, Purdue University, 550 Stadium Mall Drive, West Lafayette, IN, 47907, USA
| | - Tolulope Odimayomi
- Division of Environmental and Ecological Engineering, Purdue University, West Lafayette, IN, 47907, USA
- Civil and Environmental Engineering, Virginia Tech, 750 Drillfield Drive, Blacksburg, VA, 24061, USA
| | - Andrew J. Whelton
- Lyles School of Civil Engineering, Division of Environmental and Ecological Engineering, Purdue University, 550 Stadium Mall Drive, West Lafayette, IN, 47907, USA
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8
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Martinez Paz EF, Raskin L, Wigginton KR, Kerkez B. Toward the autonomous flushing of building plumbing: Characterizing oxidation-reduction potential and temperature sensor dynamics. WATER RESEARCH 2024; 251:121098. [PMID: 38219686 DOI: 10.1016/j.watres.2023.121098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 12/05/2023] [Accepted: 12/30/2023] [Indexed: 01/16/2024]
Abstract
Manual flushing of building plumbing is commonly used to address water quality issues that arise from water stagnation. Autonomous flushing informed by sensors has the potential to aid in the management of building plumbing, but a number of knowledge gaps hinder its application. This study evaluates autonomous flushing of building plumbing with online sensor and actuator nodes deployed under kitchen sinks in five residential houses. Online oxidation-reduction potential (ORP) and temperature data were collected for nine weeks during the winter and summer in houses with both free chlorine and chloramine. ORP levels in houses with free chlorine residuals decreased after overnight stagnation. The overnight decrease in ORP was not observed when tap water was automatically flushed for five minutes at 6:00 h every morning. ORP levels in houses with chloramine residuals did not decrease consistently after overnight stagnation, and daily automated flushes did not have an observable effect on the ORP signals. Additional laboratory experiments were carried out to evaluate ORP signals during chlorine decay and after incremental changes in chlorine, as would be expected in building plumbing conditions. Results from the lab and field deployments suggest on-line ORP sensors may be used to detect free chlorine decay due to stagnating water, but are not as effective in detecting chloramine decay. However, field results also suggest ORP may not respond as expected on a timely manner after free chlorine or chloramine have been restored, hindering their applicability in developing control algorithms. In this paper we tested twice-daily five-minute automatic flushing and found that it counteracts water quality degradation associated with overnight stagnation in free chlorine systems. An automatic sensor-based flushing is proposed using online temperature sensor data to determine when flushing has reached water from the main. The results suggest that flushing informed by temperature sensors can reduce the flushing time by 46 % compared to the preset five-minute static flush.
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Affiliation(s)
- Ernesto F Martinez Paz
- Department of Civil and Environmental Engineering, University of Michigan, 2350 Hayward Ave., 2044 GG Brown, Ann Arbor, MI 48109, USA
| | - Lutgarde Raskin
- Department of Civil and Environmental Engineering, University of Michigan, 2350 Hayward Ave., 2044 GG Brown, Ann Arbor, MI 48109, USA
| | - Krista R Wigginton
- Department of Civil and Environmental Engineering, University of Michigan, 2350 Hayward Ave., 2044 GG Brown, Ann Arbor, MI 48109, USA.
| | - Branko Kerkez
- Department of Civil and Environmental Engineering, University of Michigan, 2350 Hayward Ave., 2044 GG Brown, Ann Arbor, MI 48109, USA.
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9
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Abkar L, Moghaddam HS, Fowler SJ. Microbial ecology of drinking water from source to tap. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168077. [PMID: 37914126 DOI: 10.1016/j.scitotenv.2023.168077] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 10/20/2023] [Accepted: 10/21/2023] [Indexed: 11/03/2023]
Abstract
As drinking water travels from its source, through various treatment processes, hundreds to thousands of kilometres of distribution network pipes, to the taps in private homes and public buildings, it is exposed to numerous environmental changes, as well as other microbes living in both water and on surfaces. This review aims to identify the key locations and factors that are associated with changes in the drinking water microbiome throughout conventional urban drinking water systems from the source to the tap water. Over the past 15 years, improvements in cultivation-independent methods have enabled studies that allow us to answer such questions. As a result, we are beginning to move towards predicting the impacts of disturbances and interventions resulting ultimately in management of drinking water systems and microbial communities rather than mere observation. Many challenges still exist to achieve effective management, particularly within the premise plumbing environment, which exhibits diverse and inconsistent conditions that may lead to alterations in the microbiota, potentially presenting public health risks. Finally, we recommend the establishment of global collaborative projects on the drinking water microbiome that will enhance our current knowledge and lead to tools for operators and researchers alike to improve global access to high-quality drinking water.
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Affiliation(s)
- Leili Abkar
- Civil Engineering Department, University of British Columbia, Canada.
| | | | - S Jane Fowler
- Department of Biological Sciences, Simon Fraser University, Canada.
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10
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Huang CK, Weerasekara A, Lu J, Carter R, Weynberg KD, Thomson R, Bell S, Guo J. Extended water stagnation in buildings during the COVID-19 pandemic increases the risks posed by opportunistic pathogens. WATER RESEARCH X 2023; 21:100201. [PMID: 38098883 PMCID: PMC10719583 DOI: 10.1016/j.wroa.2023.100201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 09/05/2023] [Accepted: 09/09/2023] [Indexed: 12/17/2023]
Abstract
The regrowth and subsequent exposure of opportunistic pathogens (OPs) whilst reopening buildings that have been locked down due to the stay-at-home restrictions to limit the spread of COVID-19, is a public health concern. To better understand such microbiological risks due to lowered occupancy and water demand in buildings, first and post-flush water samples (n = 48) were sampled from 24 drinking water outlets from eight university buildings in two campuses (urban and rural), with various end-user occupancies. Both campuses were served with chlorinated water originating from a single drinking water distribution system in South-East Queensland, situated 14 km apart, where the rural campus had lower chlorine residuals. Culture-dependent and culture-independent methods (such as flow cytometry, qPCR and 16S rRNA gene amplicon sequencing) were used concurrently to comprehensively characterise the OPs of interest (Legionella spp., Pseudomonas aeruginosa, and nontuberculous mycobacteria (NTM)) and the premise plumbing microbiome. Results showed that buildings with extended levels of stagnation had higher and diverse levels of microbial growth, as observed in taxonomic structure and composition of the microbial communities. NTM were ubiquitous in all the outlets sampled, regardless of campus or end-user occupancy of the buildings. qPCR and culture demonstrated prevalent and higher concentrations of NTM in buildings (averaging 3.25 log10[estimated genomic copies/mL]) with extended stagnation in the urban campus. Furthermore, flushing the outlets for 30 minutes restored residual and total chlorine, and subsequently decreased the levels of Legionella by a reduction of 1 log. However, this approach was insufficient to restore total and residual chlorine levels for the outlets in the rural campus, where both Legionella and NTM levels detected by qPCR remained unchanged, regardless of building occupancy. Our findings highlight that regular monitoring of operational parameters such as residual chlorine levels, and the implementation of water risk management plans are important for non-healthcare public buildings, as the levels of OPs in these environments are typically not assessed.
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Affiliation(s)
- Casey K Huang
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, QLD 4072, Australia
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, QLD 4102, Australia
| | - Anjani Weerasekara
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, QLD 4072, Australia
- Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, QLD 4102, Australia
| | - Ji Lu
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, QLD 4072, Australia
| | - Robyn Carter
- Respiratory Research Unit, Gallipoli Medical Research Institute, QLD 4120, Australia
| | - Karen D. Weynberg
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Brisbane, QLD 4072, Australia
| | - Rachel Thomson
- Respiratory Research Unit, Gallipoli Medical Research Institute, QLD 4120, Australia
- Greenslopes Clinical Unit, The University of Queensland, QLD Australia
| | - Scott Bell
- Adult Cystic Fibrosis Centre, The Prince Charles Hospital, Australia
- Child Health Research Centre, Faculty of Medicine, The University of Queensland, QLD Australia
- Translational Research Institute, Australia
| | - Jianhua Guo
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, QLD 4072, Australia
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11
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Glassmeyer ST, Burns EE, Focazio MJ, Furlong ET, Gribble MO, Jahne MA, Keely SP, Kennicutt AR, Kolpin DW, Medlock Kakaley EK, Pfaller SL. Water, Water Everywhere, but Every Drop Unique: Challenges in the Science to Understand the Role of Contaminants of Emerging Concern in the Management of Drinking Water Supplies. GEOHEALTH 2023; 7:e2022GH000716. [PMID: 38155731 PMCID: PMC10753268 DOI: 10.1029/2022gh000716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 09/21/2023] [Accepted: 09/21/2023] [Indexed: 12/30/2023]
Abstract
The protection and management of water resources continues to be challenged by multiple and ongoing factors such as shifts in demographic, social, economic, and public health requirements. Physical limitations placed on access to potable supplies include natural and human-caused factors such as aquifer depletion, aging infrastructure, saltwater intrusion, floods, and drought. These factors, although varying in magnitude, spatial extent, and timing, can exacerbate the potential for contaminants of concern (CECs) to be present in sources of drinking water, infrastructure, premise plumbing and associated tap water. This monograph examines how current and emerging scientific efforts and technologies increase our understanding of the range of CECs and drinking water issues facing current and future populations. It is not intended to be read in one sitting, but is instead a starting point for scientists wanting to learn more about the issues surrounding CECs. This text discusses the topical evolution CECs over time (Section 1), improvements in measuring chemical and microbial CECs, through both analysis of concentration and toxicity (Section 2) and modeling CEC exposure and fate (Section 3), forms of treatment effective at removing chemical and microbial CECs (Section 4), and potential for human health impacts from exposure to CECs (Section 5). The paper concludes with how changes to water quantity, both scarcity and surpluses, could affect water quality (Section 6). Taken together, these sections document the past 25 years of CEC research and the regulatory response to these contaminants, the current work to identify and monitor CECs and mitigate exposure, and the challenges facing the future.
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Affiliation(s)
- Susan T. Glassmeyer
- U.S. Environmental Protection AgencyOffice of Research and DevelopmentCincinnatiOHUSA
| | | | - Michael J. Focazio
- Retired, Environmental Health ProgramEcosystems Mission AreaU.S. Geological SurveyRestonVAUSA
| | - Edward T. Furlong
- Emeritus, Strategic Laboratory Sciences BranchLaboratory & Analytical Services DivisionU.S. Geological SurveyDenverCOUSA
| | - Matthew O. Gribble
- Gangarosa Department of Environmental HealthRollins School of Public HealthEmory UniversityAtlantaGAUSA
| | - Michael A. Jahne
- U.S. Environmental Protection AgencyOffice of Research and DevelopmentCincinnatiOHUSA
| | - Scott P. Keely
- U.S. Environmental Protection AgencyOffice of Research and DevelopmentCincinnatiOHUSA
| | - Alison R. Kennicutt
- Department of Civil and Mechanical EngineeringYork College of PennsylvaniaYorkPAUSA
| | - Dana W. Kolpin
- U.S. Geological SurveyCentral Midwest Water Science CenterIowa CityIAUSA
| | | | - Stacy L. Pfaller
- U.S. Environmental Protection AgencyOffice of Research and DevelopmentCincinnatiOHUSA
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12
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Ghoochani S, Hadiuzzaman M, Mirza N, Brown SP, Salehi M. Effects of water chemistry and flow on lead release from plastic pipes versus copper pipes, implications for plumbing decontamination. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 337:122520. [PMID: 37678732 DOI: 10.1016/j.envpol.2023.122520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 08/25/2023] [Accepted: 09/04/2023] [Indexed: 09/09/2023]
Abstract
Despite being corrosion-resistant, plastic potable water pipes might accumulate heavy metals on their surface if they convey metal-contaminated tap water. This study examined the influence of water pH and flow conditions on lead (Pb) release from new and biofilm-laden potable water pipes to provide insights regarding decontamination. For this purpose, biofilms were grown onto new crosslinked polyethylene (PEX-A), high-density polyethylene (HDPE), and copper pipes for three months. Lead was then deposited onto the new and biofilm-laden pipes through 5 d exposure experiments under flow conditions. After that, lead release experiments were conducted by exposing the lead-accumulated pipes to lead-free synthetic tap water for 5 d, under both stagnant and water flow conditions. The metal accumulation study showed no significant difference in lead uptake by new pipes and their biofilm-laden counterparts under flow conditions. This could be attributed to the detachment of biofilms that have accumulated lead as water flows through the pipes. Water flow conditions significantly influenced the lead release from new and biofilm-laden water pipes. A lower water pH of 5.0 increased the release of lead from plastic pipes into the contact water, compared to pH 6.0 and 7.8. The greatest percentage of lead was released from biofilm-laden HDPE pipes (5.3%, 120 h) compared to biofilm-laden copper pipes (3.9%, 6 h) and PEX-A (3.7%, 120 h) and after exposure to lead-free synthetic tap water at pH 5.0, under stagnant conditions. On the other hand, under water flow conditions, the greatest lead release was found for new PEX-A pipes (4.4%, 120 h), new HDPE pipes (2.7%, 120 h), and biofilm-laden copper pipes (3.7%, 2 h).
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Affiliation(s)
- Shima Ghoochani
- Department of Civil Engineering, The University of Memphis, Memphis, TN, USA
| | - Md Hadiuzzaman
- Department of Civil Engineering, University of Missouri, Columbia, MO, USA
| | - Nahreen Mirza
- Department of Biological Sciences, The University of Memphis, Memphis, TN, USA
| | - Shawn P Brown
- Department of Biological Sciences, The University of Memphis, Memphis, TN, USA
| | - Maryam Salehi
- Department of Civil Engineering, University of Missouri, Columbia, MO, USA.
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13
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Clements E, Irwin C, Taflanidis A, Bibby K, Nerenberg R. Impact of fixture purging on water age and excess water usage, considering stochastic water demands. WATER RESEARCH 2023; 245:120643. [PMID: 37748346 DOI: 10.1016/j.watres.2023.120643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 09/13/2023] [Accepted: 09/17/2023] [Indexed: 09/27/2023]
Abstract
Higher water ages are linked with water quality decline as chlorine dissipates, temperatures become more favorable for microbial growth, and metals and organic matter leach from the pipes. Water fixtures with automated purging devices can limit water age in premise plumbing systems, but also increase water use. To develop purging strategies that lower age while also minimizing water use, the stochastic nature of water demands must be considered. In this research, a hydraulic plumbing network model, with stochastic demands at fixtures, was used to compare water age and water use for five purging conditions: purging at regular intervals, "smart" purging (considering the time of last use), purging with different volumes of water, purging at different fixtures, and the purging with different levels of home occupancy. Higher purging frequency and volume resulted in lower water ages, but higher water use. Purging greatly reduced the variability in water ages, avoiding extreme ages entirely. Water age was minimized by scheduling the purging around occupancy behavior, such as before the occupants wake up or return from work. Scheduled purging used more water than smart purging. Purging after 12 h of nonuse used only 55% of the additional water required for purging every 12 h. Purging after 24 h of nonuse at the kitchen tap and shower used only 38% of the additional water required for purging every 24 h, while maintaining lower water ages and removing the variability in water ages. While larger purging volumes had a greater impact on water age, there were diminishing returns. Purging has a larger impact on low-occupancy homes because fixtures have less frequent use. Overall, this research provides a methodology to compare purging strategies that minimize both water age and water use. While the numerical results presented here are only valid for the specific layout and usage habits, they provide insights and trends applicable to other cases.
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Affiliation(s)
- Emily Clements
- Department of Civil and Environmental Engineering and Earth Sciences 156 Fitzpatrick Hall, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Christopher Irwin
- Department of Civil and Environmental Engineering and Earth Sciences 156 Fitzpatrick Hall, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Alexandros Taflanidis
- Department of Civil and Environmental Engineering and Earth Sciences 156 Fitzpatrick Hall, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Kyle Bibby
- Department of Civil and Environmental Engineering and Earth Sciences 156 Fitzpatrick Hall, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Robert Nerenberg
- Department of Civil and Environmental Engineering and Earth Sciences 156 Fitzpatrick Hall, University of Notre Dame, Notre Dame, IN 46556, USA.
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14
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Kunz JM, Hannapel E, Vander Kelen P, Hils J, Hoover ER, Edens C. Effects of the COVID-19 Pandemic on Legionella Water Management Program Performance across a United States Lodging Organization. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:6885. [PMID: 37835155 PMCID: PMC10572137 DOI: 10.3390/ijerph20196885] [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: 07/19/2023] [Revised: 09/21/2023] [Accepted: 09/27/2023] [Indexed: 10/15/2023]
Abstract
Legionella, the bacterium that causes Legionnaires' disease, can grow and spread in building water systems and devices. The COVID-19 pandemic impacted building water systems through reductions in water usage. Legionella growth risk factors can be mitigated through control measures, such as flushing, to address stagnation, as part of a water management program (WMP). A national lodging organization (NLO) provided WMP data, including Legionella environmental testing results for periods before and during the pandemic. The statistical analysis revealed an increased risk of water samples testing positive for Legionella during the pandemic, with the greatest increase in risk observed at the building's cold-water entry test point. Sample positivity did not vary by season, highlighting the importance of year-round Legionella control activities. The NLO's flushing requirements may have prevented an increased risk of Legionella growth during the pandemic. However, additional control measures may be needed for some facilities that experience Legionella detections. This analysis provides needed evidence for the use of flushing to mitigate the impacts of building water stagnation, as well as the value of routine Legionella testing for WMP validation. Furthermore, this report reinforces the idea that WMPs remain the optimal tool to reduce the risk of Legionella growth and spread in building water systems.
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Affiliation(s)
- Jasen M. Kunz
- Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Mailstop H24-11, 1600 Clifton Road, Atlanta, GA 30333, USA
| | - Elizabeth Hannapel
- Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Mailstop H24-6, 1600 Clifton Road, Atlanta, GA 30333, USA; (E.H.); (C.E.)
| | - Patrick Vander Kelen
- Division of Environmental Health Science and Practice, National Center for Environmental Health, Centers for Disease Control and Prevention, Mailstop S106-5, 4770 Buford Highway, Atlanta, GA 30341, USA; (P.V.K.); (E.R.H.)
| | - Janie Hils
- Division of Environmental Health Science and Practice, National Center for Environmental Health, Centers for Disease Control and Prevention, Mailstop S106-5, 4770 Buford Highway, Atlanta, GA 30341, USA; (P.V.K.); (E.R.H.)
- Oak Ridge Institute for Science and Education, P.O. Box 117, Oak Ridge, TN 37830, USA
| | - Edward Rickamer Hoover
- Division of Environmental Health Science and Practice, National Center for Environmental Health, Centers for Disease Control and Prevention, Mailstop S106-5, 4770 Buford Highway, Atlanta, GA 30341, USA; (P.V.K.); (E.R.H.)
| | - Chris Edens
- Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Mailstop H24-6, 1600 Clifton Road, Atlanta, GA 30333, USA; (E.H.); (C.E.)
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15
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Fasciana T, Palermo M, Arrigo I, Tricoli MR, Diquattro O, Giammanco A. Editorial: Special Issue: " Legionella pneumophila: A Microorganism with a Thousand Faces". Microorganisms 2023; 11:2392. [PMID: 37894050 PMCID: PMC10609420 DOI: 10.3390/microorganisms11102392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 09/04/2023] [Accepted: 09/06/2023] [Indexed: 10/29/2023] Open
Abstract
Legionella pneumophila is a microorganism that is able to contaminate the freshwater environment and, consequently, human-made water systems [...].
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Affiliation(s)
- Teresa Fasciana
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialities, University of Palermo, 90127 Palermo, Italy;
- Legionella Reference Laboratory, University of Palermo, 90127 Palermo, Italy; (I.A.); (M.R.T.)
| | - Mario Palermo
- Sicilian Health Department, Public Health and Environmental Risks Service, 90127 Palermo, Italy;
| | - Ignazio Arrigo
- Legionella Reference Laboratory, University of Palermo, 90127 Palermo, Italy; (I.A.); (M.R.T.)
| | - Maria Rita Tricoli
- Legionella Reference Laboratory, University of Palermo, 90127 Palermo, Italy; (I.A.); (M.R.T.)
| | - Orazia Diquattro
- Laboratory of Microbiology, A. O. Ospedali Riuniti “Villa Sofia-Cervello”, 90100 Palermo, Italy;
| | - Anna Giammanco
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialities, University of Palermo, 90127 Palermo, Italy;
- Legionella Reference Laboratory, University of Palermo, 90127 Palermo, Italy; (I.A.); (M.R.T.)
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16
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Nisar MA, Ross KE, Brown MH, Bentham R, Xi J, Hinds J, Jamieson T, Leterme SC, Whiley H. The composition of planktonic prokaryotic communities in a hospital building water system depends on both incoming water and flow dynamics. WATER RESEARCH 2023; 243:120363. [PMID: 37494744 DOI: 10.1016/j.watres.2023.120363] [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: 03/23/2023] [Revised: 07/13/2023] [Accepted: 07/14/2023] [Indexed: 07/28/2023]
Abstract
In recent years, the frequency of nosocomial infections has increased. Hospital water systems support the growth of microbes, especially opportunistic premise plumbing pathogens. In this study, planktonic prokaryotic communities present in water samples taken from hospital showers and hand basins, collected over three different sampling phases, were characterized by 16S rRNA gene amplicon sequencing. Significant differences in the abundance of various prokaryotic taxa were found through univariate and multivariate analysis. Overall, the prokaryotic communities of hospital water were taxonomically diverse and dominated by biofilm forming, corrosion causing, and potentially pathogenic bacteria. The phyla Proteobacteria, Actinobacteriota, Bacteroidota, Planctomycetota, Firmicutes, and Cyanobacteria made up 96% of the relative abundance. The α-diversity measurements of prokaryotic communities showed no difference in taxa evenness and richness based on sampling sites (shower or hand basins), sampling phases (months), and presence or absence of Vermamoeba vermiformis. However, β-diversity measurements showed significant clustering of prokaryotic communities based on sampling phases, with the greatest difference observed between the samples collected in phase 1 vs phase 2/3. Importantly, significant difference was observed in prokaryotic communities based on flow dynamics of the incoming water. The Pielou's evenness diversity index revealed a significant difference (Kruskal Wallis, p < 0.05) and showed higher species richness in low flow regime (< 13 minutes water flushing per week and ≤ 765 flushing events per six months). Similarly, Bray-Curtis dissimilarity index found significant differences (PERMANOVA, p < 0.05) in the prokaryotic communities of low vs medium/high flow regimes. Furthermore, linear discriminant analysis effect size showed that several biofilm forming (e.g., Pseudomonadales), corrosion causing (e.g., Desulfobacterales), extremely environmental stress resistant (e.g., Deinococcales), and potentially pathogenic (e.g., Pseudomonas) bacterial taxa were in higher amounts under low flow regime conditions. This study demonstrated that a hospital building water system consists of a complex microbiome that is shaped by incoming water quality and the building flow dynamics arising through usage.
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Affiliation(s)
- Muhammad Atif Nisar
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
| | - Kirstin E Ross
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
| | - Melissa H Brown
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia; ARC Training Centre for Biofilm Research and Innovation, Flinders University, Bedford Park, SA, Australia
| | - Richard Bentham
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
| | - James Xi
- Enware Australia Pty Ltd, Caringbah, NSW, Australia
| | - Jason Hinds
- Enware Australia Pty Ltd, Caringbah, NSW, Australia
| | - Tamar Jamieson
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia; Institute for Nanoscience and Technology, Flinders University, Bedford Park, SA, Australia
| | - Sophie C Leterme
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia; ARC Training Centre for Biofilm Research and Innovation, Flinders University, Bedford Park, SA, Australia; Institute for Nanoscience and Technology, Flinders University, Bedford Park, SA, Australia
| | - Harriet Whiley
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia; ARC Training Centre for Biofilm Research and Innovation, Flinders University, Bedford Park, SA, Australia.
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17
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Yao M, Zhang Y, Dai Z, Ren A, Fang J, Li X, van der Meer W, Medema G, Rose JB, Liu G. Building water quality deterioration during water supply restoration after interruption: Influences of premise plumbing configuration. WATER RESEARCH 2023; 241:120149. [PMID: 37270942 DOI: 10.1016/j.watres.2023.120149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 05/26/2023] [Accepted: 05/28/2023] [Indexed: 06/06/2023]
Abstract
Premise plumbing plays an essential role in determining the final quality of drinking water consumed by customers. However, little is known about the influences of plumbing configuration on water quality changes. This study selected parallel premise plumbing in the same building with different configurations, i.e., laboratory and toilet plumbing. Water quality deteriorations induced by premise plumbing under regular and interrupted water supply were investigated. The results showed that most of the water quality parameters did not vary under regular supply, except Zn, which was significantly increased by laboratory plumbing (78.2 to 260.7 µg/l). For the bacterial community, the Chao1 index was significantly increased by both plumbing types to a similar level (52 to 104). Laboratory plumbing significantly changed the bacterial community, but toilet plumbing did not. Remarkably, water supply interruption/restoration led to serious water quality deterioration in both plumbing types but resulted in different changes. Physiochemically, discoloration was observed only in laboratory plumbing, along with sharp increases in Mn and Zn. Microbiologically, the increase in ATP was sharper in toilet plumbing than in laboratory plumbing. Some opportunistic pathogen-containing genera, e.g., Legionella spp. and Pseudomonas spp., were present in both plumbing types but only in disturbed samples. This study highlighted the esthetic, chemical, and microbiological risks associated with premise plumbing, for which system configuration plays an important role. Attention should be given to optimizing premise plumbing design for managing building water quality.
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Affiliation(s)
- Mingchen Yao
- Key Laboratory of Drinking Water Science and Technology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing, China; Sanitary engineering, Department of Water management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, P.O. Box 5048, Delft, GA 2600, the Netherlands
| | - Yue Zhang
- Key Laboratory of Drinking Water Science and Technology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing, China
| | - Zihan Dai
- Key Laboratory of Drinking Water Science and Technology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing, China
| | - Anran Ren
- Key Laboratory of Drinking Water Science and Technology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing, China
| | - Jiaxing Fang
- Key Laboratory of Drinking Water Science and Technology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Membrane Science and Technology, Faculty of Science and Technology, University of Twente, P.O. Box 217, Enschede 7500AE, the Netherlands
| | - Xiaoming Li
- Key Laboratory of Drinking Water Science and Technology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing, China
| | - Walter van der Meer
- Membrane Science and Technology, Faculty of Science and Technology, University of Twente, P.O. Box 217, Enschede 7500AE, the Netherlands; Oasen Drinkwater, PO BOX 122, Gouda, AC 2800, the Netherlands
| | - Gertjan Medema
- Sanitary engineering, Department of Water management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, P.O. Box 5048, Delft, GA 2600, the Netherlands; KWR Watercycle Research Institute, P.O. Box 1072, Nieuwegein 3430 BB, the Netherlands; Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI 48823, United States of America
| | - Joan B Rose
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI 48823, United States of America
| | - Gang Liu
- Key Laboratory of Drinking Water Science and Technology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing, China.
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18
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Grimard-Conea M, Prévost M. Controlling Legionella pneumophila in Showerheads: Combination of Remedial Intervention and Preventative Flushing. Microorganisms 2023; 11:1361. [PMID: 37374862 DOI: 10.3390/microorganisms11061361] [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: 05/01/2023] [Revised: 05/17/2023] [Accepted: 05/20/2023] [Indexed: 06/29/2023] Open
Abstract
Shock chlorination and remedial flushing are suggested to address Legionella pneumophila (Lp) contamination in buildings or during their (re)commissioning. However, data on general microbial measurements (adenosine tri-phosphate [ATP], total cell counts [TCC]), and the abundance of Lp are lacking to support their temporary implementation with variable water demands. In this study, the weekly short-term (3-week) impact of shock chlorination (20-25 mg/L free chlorine, 16 h) or remedial flushing (5-min flush) combined with distinct flushing regimes (daily, weekly, stagnant) was investigated in duplicates of showerheads in two shower systems. Results showed that the combination of stagnation and shock chlorination prompted biomass regrowth, with ATP and TCC in the first draws reaching large regrowth factors of 4.31-7.07-fold and 3.51-5.68-fold, respectively, from baseline values. Contrastingly, remedial flushing followed by stagnation generally resulted in complete or larger regrowth in Lp culturability and gene copies (gc). Irrespective of the intervention, daily flushed showerheads resulted in significantly (p < 0.05) lower ATP and TCC, as well as lower Lp concentrations than weekly flushes, in general. Nonetheless, Lp persisted at concentrations ranging from 11 to 223 as the most probable number per liter (MPN/L) and in the same order of magnitude (103-104 gc/L) than baseline values after remedial flushing, despite daily/weekly flushing, unlike shock chlorination which suppressed Lp culturability (down 3-log) for two weeks and gene copies by 1-log. This study provides insights on the most optimal short-term combination of remedial and preventative strategies that can be considered pending the implementation of suitable engineering controls or building-wide treatment.
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Affiliation(s)
- Marianne Grimard-Conea
- Industrial Chair in Drinking Water, Department of Civil, Mining and Geological Engineering, Polytechnique Montreal, Montreal, QC H3C 3A7, Canada
| | - Michèle Prévost
- Industrial Chair in Drinking Water, Department of Civil, Mining and Geological Engineering, Polytechnique Montreal, Montreal, QC H3C 3A7, Canada
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19
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Logan-Jackson AR, Batista MD, Healy W, Ullah T, Whelton AJ, Bartrand TA, Proctor C. A Critical Review on the Factors that Influence Opportunistic Premise Plumbing Pathogens: From Building Entry to Fixtures in Residences. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:6360-6372. [PMID: 37036108 DOI: 10.1021/acs.est.2c04277] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Residential buildings provide unique conditions for opportunistic premise plumbing pathogen (OPPP) exposure via aerosolized water droplets produced by showerheads, faucets, and tubs. The objective of this review was to critically evaluate the existing literature that assessed the impact of potentially enhancing conditions to OPPP occurrence associated with residential plumbing and to point out knowledge gaps. Comprehensive studies on the topic were found to be lacking. Major knowledge gaps identified include the assessment of OPPP growth in the residential plumbing, from building entry to fixtures, and evaluation of the extent of the impact of typical residential plumbing design (e.g., trunk and branch and manifold), components (e.g., valves and fixtures), water heater types and temperature setting of operation, and common pipe materials (copper, PEX, and PVC/CPVC). In addition, impacts of the current plumbing code requirements on OPPP responses have not been assessed by any study and a lack of guidelines for OPPP risk management in residences was identified. Finally, the research required to expand knowledge on OPPP amplification in residences was discussed.
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Affiliation(s)
- Alshae' R Logan-Jackson
- Building Energy and Environment Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Marylia Duarte Batista
- Building Energy and Environment Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - William Healy
- Building Energy and Environment Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Tania Ullah
- Building Energy and Environment Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Andrew J Whelton
- Lyles School of Civil Engineering, Division of Environmental and Ecological Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Timothy A Bartrand
- Environmental Science, Policy, and Research Institute, Bala Cynwyd, Pennsylvania 19004, United States
| | - Caitlin Proctor
- Agricultural and Biological Engineering, Division of Environmental and Ecological Engineering, Purdue University, West Lafayette, Indiana 47907, United States
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20
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Lombardi A, Borriello T, De Rosa E, Di Duca F, Sorrentino M, Torre I, Montuori P, Trama U, Pennino F. Environmental Monitoring of Legionella in Hospitals in the Campania Region: A 5-Year Study. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:ijerph20085526. [PMID: 37107807 PMCID: PMC10138562 DOI: 10.3390/ijerph20085526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 04/06/2023] [Accepted: 04/13/2023] [Indexed: 05/11/2023]
Abstract
Legionella is a pathogen that colonizes soils, freshwater, and building water systems. People who are most affected are those with immunodeficiencies, so it is necessary to monitor its presence in hospitals. The purpose of this study was to evaluate the presence of Legionella in water samples collected from hospitals in the Campania region, Southern Italy. A total of 3365 water samples were collected from January 2018 to December 2022 twice a year in hospital wards from taps and showers, tank bottoms, and air-treatment units. Microbiological analysis was conducted in accordance with the UNI EN ISO 11731:2017, and the correlations between the presence of Legionella and water temperature and residual chlorine were investigated. In total, 708 samples (21.0%) tested positive. The most represented species was L. pneumophila 2-14 (70.9%). The serogroups isolated were 1 (27.7%), 6 (24.5%), 8 (23.3%), 3 (18.9%), 5 (3.1%), and 10 (1.1%). Non-pneumophila Legionella spp. represented 1.4% of the total. Regarding temperature, the majority of Legionella positive samples were found in the temperature range of 26.0-40.9 °C. An influence of residual chlorine on the presence of the bacterium was observed, confirming that chlorine disinfection is effective for controlling contamination. The positivity for serogroups other than serogroup 1 suggested the need to continue environmental monitoring of Legionella and to focus on the clinical diagnosis of other serogroups.
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Affiliation(s)
- Annalisa Lombardi
- Department of Public Health, University “Federico II”, Via Sergio Pansini N° 5, 80131 Naples, Italy
| | - Tonia Borriello
- Department of Public Health, University “Federico II”, Via Sergio Pansini N° 5, 80131 Naples, Italy
| | - Elvira De Rosa
- Department of Public Health, University “Federico II”, Via Sergio Pansini N° 5, 80131 Naples, Italy
| | - Fabiana Di Duca
- Department of Public Health, University “Federico II”, Via Sergio Pansini N° 5, 80131 Naples, Italy
| | - Michele Sorrentino
- Department of Public Health, University “Federico II”, Via Sergio Pansini N° 5, 80131 Naples, Italy
| | - Ida Torre
- Department of Public Health, University “Federico II”, Via Sergio Pansini N° 5, 80131 Naples, Italy
| | - Paolo Montuori
- Department of Public Health, University “Federico II”, Via Sergio Pansini N° 5, 80131 Naples, Italy
| | - Ugo Trama
- General Directorate of Health, Campania Region, Centro Direzionale C3, 80143 Naples, Italy
| | - Francesca Pennino
- Department of Public Health, University “Federico II”, Via Sergio Pansini N° 5, 80131 Naples, Italy
- Correspondence:
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21
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Kim T, Zhao X, LaPara TM, Hozalski RM. Flushing Temporarily Improves Microbiological Water Quality for Buildings Supplied with Chloraminated Surface Water but Has Little Effect for Groundwater Supplies. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:5453-5463. [PMID: 36952669 DOI: 10.1021/acs.est.2c08123] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Microbial communities in premise plumbing systems were investigated after more than 2 months of long-term stagnation, during a subsequent flushing event, and during post-flush stagnation. Water samples were collected from showers in buildings supplied with chlorinated groundwater, untreated groundwater, and chloraminated surface water. The building supplied with chlorinated groundwater generally had the lowest bacterial concentrations across all sites (ranging from below quantification limit to 5.2 log copies/L). For buildings supplied with untreated groundwater, bacterial concentrations (5.0 to 7.6 log copies/L) and microbial community diversity index (ACE) values were consistent throughout sampling. Nontuberculous mycobacteria (NTM) and Legionella pneumophila were not detected in any groundwater-supplied buildings. Total bacteria, Legionella spp., and NTM were abundant in the surface water-supplied buildings following long-term stagnation (up to 7.6, 6.2, and 7.6 log copies/L, respectively). Flushing decreased these concentrations by ∼1 to >4 log units and reduced microbial community diversity, but the communities largely recovered within a week of post-flush stagnation. The results suggest that buildings supplied with disinfected surface water are more likely than buildings supplied with treated or untreated groundwater to experience deleterious changes in microbiological water quality during stagnation and that the water quality improvements from flushing with chloraminated water, while substantial, are short-lived.
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Affiliation(s)
- Taegyu Kim
- Department of Civil, Environmental, and Geo- Engineering, University of Minnesota Twin Cities, 500 Pillsbury Drive S.E., Minneapolis, Minnesota 55455, United States
| | - Xiaotian Zhao
- Department of Civil, Environmental, and Geo- Engineering, University of Minnesota Twin Cities, 500 Pillsbury Drive S.E., Minneapolis, Minnesota 55455, United States
| | - Timothy M LaPara
- Department of Civil, Environmental, and Geo- Engineering, University of Minnesota Twin Cities, 500 Pillsbury Drive S.E., Minneapolis, Minnesota 55455, United States
- Biotechnology Institute, University of Minnesota Twin Cities, 1479 Gortner Avenue, St. Paul, Minnesota 55108, United States
| | - Raymond M Hozalski
- Department of Civil, Environmental, and Geo- Engineering, University of Minnesota Twin Cities, 500 Pillsbury Drive S.E., Minneapolis, Minnesota 55455, United States
- Biotechnology Institute, University of Minnesota Twin Cities, 1479 Gortner Avenue, St. Paul, Minnesota 55108, United States
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22
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Vosloo S, Huo L, Chauhan U, Cotto I, Gincley B, Vilardi KJ, Yoon B, Bian K, Gabrielli M, Pieper KJ, Stubbins A, Pinto AJ. Gradual Recovery of Building Plumbing-Associated Microbial Communities after Extended Periods of Altered Water Demand during the COVID-19 Pandemic. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:3248-3259. [PMID: 36795589 PMCID: PMC9969676 DOI: 10.1021/acs.est.2c07333] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 02/06/2023] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
COVID-19 pandemic-related building restrictions heightened drinking water microbiological safety concerns post-reopening due to the unprecedented nature of commercial building closures. Starting with phased reopening (i.e., June 2020), we sampled drinking water for 6 months from three commercial buildings with reduced water usage and four occupied residential households. Samples were analyzed using flow cytometry and full-length 16S rRNA gene sequencing along with comprehensive water chemistry characterization. Prolonged building closures resulted in 10-fold higher microbial cell counts in the commercial buildings [(2.95 ± 3.67) × 105 cells mL-1] than in residential households [(1.11 ± 0.58) × 104 cells mL-1] with majority intact cells. While flushing reduced cell counts and increased disinfection residuals, microbial communities in commercial buildings remained distinct from those in residential households on the basis of flow cytometric fingerprinting [Bray-Curtis dissimilarity (dBC) = 0.33 ± 0.07] and 16S rRNA gene sequencing (dBC = 0.72 ± 0.20). An increase in water demand post-reopening resulted in gradual convergence in microbial communities in water samples collected from commercial buildings and residential households. Overall, we find that the gradual recovery of water demand played a key role in the recovery of building plumbing-associated microbial communities as compared to short-term flushing after extended periods of reduced water demand.
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Affiliation(s)
- Solize Vosloo
- Department
of Civil and Environmental Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 021115, United States
| | - Linxuan Huo
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, 311 Ferst Drive, Atlanta, Georgia 30318, United States
| | - Umang Chauhan
- Department
of Civil and Environmental Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 021115, United States
| | - Irmarie Cotto
- Department
of Civil and Environmental Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 021115, United States
| | - Benjamin Gincley
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, 311 Ferst Drive, Atlanta, Georgia 30318, United States
| | - Katherine J. Vilardi
- Department
of Civil and Environmental Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 021115, United States
| | - Bryan Yoon
- Department
of Civil and Environmental Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 021115, United States
| | - Kaiqin Bian
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, 311 Ferst Drive, Atlanta, Georgia 30318, United States
| | - Marco Gabrielli
- Dipartimento
di Ingegneria Civile e Ambientale - Sezione Ambientale, Politecnico di Milano, 20133 Milan, Italy
| | - Kelsey J. Pieper
- Department
of Civil and Environmental Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 021115, United States
| | - Aron Stubbins
- Department
of Civil and Environmental Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 021115, United States
| | - Ameet J. Pinto
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, 311 Ferst Drive, Atlanta, Georgia 30318, United States
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23
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Molina JJ, Bennassar M, Palacio E, Crespi S. Impact of prolonged hotel closures during the COVID-19 pandemic on Legionella infection risks. Front Microbiol 2023; 14:1136668. [PMID: 36910223 PMCID: PMC9998907 DOI: 10.3389/fmicb.2023.1136668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 02/10/2023] [Indexed: 03/14/2023] Open
Abstract
In general, it is accepted that water stagnation and lack or poor maintenance in buildings are risk factors for Legionella growth. Then, in theory, the prolonged hotel closures due to the COVID-19 pandemic may have increased the risk of Legionella infections. However, there are very few field studies comparing the level of Legionella colonization in buildings before the pandemic and the new situation created after the lockdown. The objective of this study was to analyze these differences in a group of hotels that experienced prolonged closures in 2020 due to the COVID-19 pandemic. We have studied the Legionella spp. results, analyzed by standard culture, from the domestic water distribution systems of 73 hotels that experienced closures (from 1 to >4 months) during 2020, immediately after the reopening. The results were compared with those obtained in similar samplings of 2019. For the comparative analysis, we divided the hotels in two groups: Group A that have suffered closures for ≤3 months and Group B that remained closed for more than 3 months, both in relation to the opening period of 2019. In the Group B (36 sites), the frequency of positive samples in the hot water system increased from 6.7% in 2019 to 14.0% in 2020 (p < 0.05). In the Group A (37 sites), no significant differences were observed. No statistically significant differences were observed in terms of positive sites (defined as hotels with at least 1 positive sample), Legionella spp. concentrations and prevalence of Legionella pneumophila sg1 between the samplings of the two periods studied. The results suggest that hotels that suffered the longest prolonged closures (> 3 months) could have carried a higher risk of exposure to Legionella in the domestic hot water system. These findings highlight the importance of adequate preopening cleaning and disinfection procedures for hotel water systems, and the convenience of considering the most effective disinfection methods especially for hot water systems and after prolonged closure periods.
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Affiliation(s)
- Jhon J. Molina
- Environmental Health and Laboratory Services, Biolinea Int., Palma, Spain
- Environmental Analytical Chemistry Laboratory, Department of Chemistry, University of the Balearic Islands, Palma, Spain
| | | | - Edwin Palacio
- Environmental Analytical Chemistry Laboratory, Department of Chemistry, University of the Balearic Islands, Palma, Spain
| | - Sebastian Crespi
- Environmental Health and Laboratory Services, Biolinea Int., Palma, Spain
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24
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Scanlon M, Taylor E, Waltz K. Evaluating Efficacy of a COVID-19 Alternative Care Site Preparedness Assessment Tool for Catastrophic Healthcare Surge Capacity during Pandemic Response. Healthcare (Basel) 2023; 11:324. [PMID: 36766899 PMCID: PMC9914666 DOI: 10.3390/healthcare11030324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/23/2022] [Accepted: 01/18/2023] [Indexed: 01/24/2023] Open
Abstract
During the COVID-19 pandemic, implementing catastrophic healthcare surge capacity required a network of facility infrastructure beyond the immediate hospital to triage the rapidly growing numbers of infected individuals and treat emerging disease cases. Providing regional continuity-of-care requires an assessment of buildings for alternative care sites (ACS) to extend healthcare operations into non-healthcare settings. The American Institute of Architects (AIA) appointed a COVID-19 ACS Task Force involving architects, engineers, public health, and healthcare professionals to conduct a charrette (i.e., intensive workshop) to establish guidance during the alert phase of the pandemic. The task force developed an ACS Preparedness Assessment Tool (PAT) for healthcare teams to assist with their rapid evaluation of building sites for establishing healthcare operations in non-healthcare settings. The tool was quickly updated (V2.0) and then translated into multiple languages. Subsequently, the authors of this manuscript reviewed the efficacy of the PAT V2.0 in the context of reported case studies from healthcare teams who developed a COVID-19 ACS in community settings. In summary, policy makers should re-examine the role of the built environment during emergency pandemic response and its impact on patients and health professionals. An updated ACS PAT tool should be established as part of the public health preparedness for implementing catastrophic healthcare surge capacity.
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Affiliation(s)
- Molly Scanlon
- Department of Community, Environment, and Policy, Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, AZ 85724, USA
| | - Ellen Taylor
- Research, The Center for Health Design, Concord, CA 94520, USA
| | - Kirsten Waltz
- Architecture & Planning, Johns Hopkins Health System, Baltimore, MD 21201, USA
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25
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Mare R, Mare C, Hadarean A, Hotupan A, Rus T. COVID-19 and Water Variables: Review and Scientometric Analysis. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:957. [PMID: 36673718 PMCID: PMC9859563 DOI: 10.3390/ijerph20020957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 12/29/2022] [Accepted: 12/30/2022] [Indexed: 06/17/2023]
Abstract
COVID-19 has changed the world since 2020, and the field of water specifically, boosting scientific productivity (in terms of published articles). This paper focuses on the influence of COVID-19 on scientific productivity with respect to four water variables: (i) wastewater, (ii) renewable water resources, (iii) freshwater withdrawal, and (iv) access to improved and safe drinking water. The field's literature was firstly reviewed, and then the maps were built, emphasizing the strong connections between COVID-19 and water-related variables. A total of 94 countries with publications that assess COVID-19 vs. water were considered and evaluated for how they clustered. The final step of the research shows that, on average, scientific productivity on the water topic was mostly conducted in countries with lower COVID-19 infection rates but higher development levels as represented by gross domestic product (GDP) per capita and the human development index (HDI). According to the statistical analysis, the water-related variables are highly significant, with positive coefficients. This validates that countries with higher water-related values conducted more research on the relationship with COVID-19. Wastewater and freshwater withdrawal had the highest impact on the scientific productivity with respect to COVID-19. Access to safe drinking water becomes insignificant in the presence of the development parameters.
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Affiliation(s)
- Roxana Mare
- Department of Building Services Engineering, Faculty of Building Services Engineering, Technical University of Cluj-Napoca, 128-130 21 Decembrie 1989 Blv., 400604 Cluj-Napoca, Romania
| | - Codruța Mare
- Department of Statistics-Forecasts-Mathematics, Faculty of Economics and Business Administration, Babes-Bolyai University, 58-60 Teodor Mihali Str., 400591 Cluj-Napoca, Romania
- Interdisciplinary Centre for Data Science, Babes-Bolyai University, 68 Avram Iancu Str., 4th Floor, 400083 Cluj-Napoca, Romania
| | - Adriana Hadarean
- Department of Building Services Engineering, Faculty of Building Services Engineering, Technical University of Cluj-Napoca, 128-130 21 Decembrie 1989 Blv., 400604 Cluj-Napoca, Romania
| | - Anca Hotupan
- Department of Building Services Engineering, Faculty of Building Services Engineering, Technical University of Cluj-Napoca, 128-130 21 Decembrie 1989 Blv., 400604 Cluj-Napoca, Romania
| | - Tania Rus
- Department of Building Services Engineering, Faculty of Building Services Engineering, Technical University of Cluj-Napoca, 128-130 21 Decembrie 1989 Blv., 400604 Cluj-Napoca, Romania
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26
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Temporal trends in legionellosis national notification data and the effect of COVID-19, Switzerland, 2000-2020. Int J Hyg Environ Health 2023; 247:113970. [PMID: 35508422 DOI: 10.1016/j.ijheh.2022.113970] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/31/2022] [Accepted: 04/04/2022] [Indexed: 11/21/2022]
Abstract
The notification rate of legionellosis in Switzerland and other European countries has markedly increased over the last 20 years. Here, we investigated the Swiss notification data on legionellosis from 2000 to 2020 in regards of overall time trend, content and data quality. We further explored the impact of the COVID-19 pandemic on the reported case numbers using an interrupted time series approach. Between 2000 and 2020, 5980 cases were included in our analysis. The annual crude notification rate for legionellosis cases increased from 1.1/100,000 population (CI: 0.9-1.4) in 2000 to 5.6/100,000 population (CI: 5.1-6.1) in 2020. In recent years, the summer peaks have been more pronounced and some shifted earlier in the year. The highest notification rate was recorded in 2018 with 6.7/100,000 population (CI: 6.2-7.3). The hospitalisation rate for notified cases remained high across all study years (89.9%), while the case fatality rate slightly decreased (from 7.7% to 3.6%). COVID-19 containment measures, such as travel restrictions and/or related behavioural changes, are associated with a temporary decline in cases of 35%. Overall, the quality of the notification data was good. Clinical data were more susceptible to interferences than data from laboratory reporting, which could be observed most clearly in the decline of clinical reports by 4.3 percentage points in 2020. As the case classification for Legionnaires' disease includes pneumonia symptoms, this decline could lead to an underestimation of Legionnaires' disease cases, yet the continuous reporting though the diagnostic laboratories suggested a robust surveillance system for legionellosis in Switzerland.
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27
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Ye JJ, Zheng JY, Chen YH, Kao YL, Kao YC, Chao SW. Investigation of a cluster of Legionnaires' disease during the outbreak of coronavirus disease 2019 pandemic in northeastern Taiwan, June 2021. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2022; 55:1159-1167. [PMID: 35570184 PMCID: PMC9068600 DOI: 10.1016/j.jmii.2022.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 03/25/2022] [Accepted: 04/16/2022] [Indexed: 12/27/2022]
Abstract
PURPOSE To describe the investigation and intervention of a cluster of Legionnaires' disease detected during the outbreak of coronavirus disease 2019 (COVID-19) pandemic. METHODS From June 7 to 22, 2021, 15 cases in the neighborhood near our hospital were detected. Information about residence, workplace, hospital visit, and potential exposures was collected. Sampling and decontamination were performed for potential sources. RESULTS All 15 patients had pneumonia when visiting the emergency room with negative COVID-19 test results. Most patients were male (73.3%) with the mean age of 65.7 years. The most common comorbidities were diabetes mellitus (40.0%) and hypertension (40%). The most common symptom was fever (93.3%). Two (13.3%) patients needed mechanical ventilators. Fever subsided within 2 days of treatment for most cases (85.7%). Five cases had exposure history at our hospital, and the other 10 lived or worked in the area within 2 km of our hospital, mostly in buildings A and B. Water sampling was carried out for our hospital, buildings A and B; one water sample from a cooling tower in our hospital cultured positive for Legionella bacteria. Early testing and treatment for suspected cases were carried out for the outbreak, and all cases were discharged with pneumonia resolution. CONCLUSION This was a community outbreak of Legionnaires' disease near our hospital. COVID-19 tests were repeated frequently before testing for Legionnaires' disease during the COVID-19 pandemic. Early recognition of Legionnaires' disease and timely treatment improved outcome.
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Affiliation(s)
- Jung-Jr Ye
- Division of Infectious Diseases, Department of Internal Medicine, Chang Gung Memorial Hospital at Kee-Lung, Kee-Lung, Taiwan,College of Medicine, Chang Gung University, Taoyuan, Taiwan,Corresponding author. 12F., No.222, Maijin Rd., Anle Dist., Keelung City, 204, Taiwan. Fax: +886 2 24335342
| | - Jun-Yuan Zheng
- Division of Infectious Diseases, Department of Internal Medicine, Chang Gung Memorial Hospital at Kee-Lung, Kee-Lung, Taiwan
| | - Ya-Hsuan Chen
- Hospital Infection Control Team, Chang Gung Memorial Hospital at Kee-Lung, Kee-Lung, Taiwan
| | - Ya-Ling Kao
- Hospital Infection Control Team, Chang Gung Memorial Hospital at Kee-Lung, Kee-Lung, Taiwan
| | - Yu-Chin Kao
- Hospital Infection Control Team, Chang Gung Memorial Hospital at Kee-Lung, Kee-Lung, Taiwan
| | - Shao-Wen Chao
- Department of Laboratory Medicine, Chang Gung Memorial Hospital at Kee-Lung, Kee-Lung, Taiwan
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28
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Li J, Ren A, van der Mark E, Liu G. Direct evidence of microbiological water quality changes on bacterial quantity and community caused by plumbing system. J Environ Sci (China) 2022; 116:175-183. [PMID: 35219416 DOI: 10.1016/j.jes.2021.04.028] [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: 04/15/2021] [Revised: 04/22/2021] [Accepted: 04/25/2021] [Indexed: 06/14/2023]
Abstract
Drinking water quality deteriorates from treatment plant to customer taps, especially in the plumbing system. There is no direct evidence about what the differences are contributed by plumbing system. This study compared the water quality in the water main and at customer tap by preparing a sampling tap on the water main. The biomass was quantified by adenosine triphosphate (ATP) and the microbial community was profiled by 454 pyrosequencing. The results showed that in distribution pipes, biofilm contributed >94% of the total biomass, while loose deposits showed little contribution (< 2%) because of the low amount of loose deposits. The distribution of biological stable water had minor effects on the microbiocidal water quality regarding both quantity (ATP 1 ng/L vs. 1.7 ng/L) and community of the bacteria. Whereas the plumbing system has significant contribution to the increase of active biomass (1.7 ng/L vs. 2.9 ng/L) and the changes of bacterial community. The relative abundance of Sphingomonas spp. at tap (22%) was higher than that at water main (2%), while the relative abundance of Pseudomonas spp. in tap water (15%) was lower than that in the water from street water main (29%). Though only one location was prepared and studied, the present study showed that the protocol of making sampling tap on water main offered directly evidences about the impacts of plumbing system on tap water quality, which makes it possible to distinguish and study the processes in distribution system and plumbing system separately.
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Affiliation(s)
- Jun Li
- Key Laboratory of Drinking Water Science and Technology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Anran Ren
- Key Laboratory of Drinking Water Science and Technology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ed van der Mark
- Dunea Water Company, Plaza of the United Nations 11-15, Zoetermeer 2700 AT, the Netherlands
| | - Gang Liu
- Key Laboratory of Drinking Water Science and Technology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China; Sanitary engineering, Department of Water management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft 2600 GA, the Netherlands.
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29
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Scanlon MM, Gordon JL, Tonozzi AA, Griffin SC. Reducing the Risk of Healthcare Associated Infections from Legionella and Other Waterborne Pathogens Using a Water Management for Construction (WMC) Infection Control Risk Assessment (ICRA) Tool. Infect Dis Rep 2022; 14:341-359. [PMID: 35645218 PMCID: PMC9149880 DOI: 10.3390/idr14030039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 04/26/2022] [Accepted: 04/28/2022] [Indexed: 11/16/2022] Open
Abstract
Construction activities in healthcare settings potentially expose building occupants to waterborne pathogens including Legionella and have been associated with morbidity and mortality. A Water Management for Construction—Infection Control Risk Assessment (WMC-ICRA) tool was developed addressing gaps in building water management programs. This enables healthcare organizations to meet the requirements of ANSI/ASHRAE Standard 188 referenced in numerous guidelines and regulations. A WMC-ICRA was modeled after the ICRA required for prevention and control of airborne pathogens to reduce the risk of healthcare associated infections. The tool allows users to evaluate risk from waterborne pathogen exposure by analyzing construction activities by project category and building occupant risk group. The users then select an appropriate level of risk mitigation measures. Technical aspects (e.g., water age/stagnation, flushing, filtration, disinfection, validation testing), are presented to assist with implementation. An exemplar WMC-ICRA tool is presented as ready for implementation by infection prevention and allied professionals, addressing current gaps in water management, morbidity/mortality risk, and regulatory compliance. To reduce exposure to waterborne pathogens in healthcare settings and improve regulatory compliance, organizations should examine the WMC-ICRA tool, customize it for organization-specific needs, while formulating an organizational policy to implement during all construction activities.
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Affiliation(s)
- Molly M. Scanlon
- Standards and Research, Phigenics, LLC, 3S701 West Avenue, Suite 100, Warrenville, IL 60555, USA
- Department of Community, Environment and Policy, Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, AZ 85724, USA;
- Correspondence: ; Tel.: +1-844-850-4087
| | | | | | - Stephanie C. Griffin
- Department of Community, Environment and Policy, Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, AZ 85724, USA;
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Lancaster EC, Lee J. Potential environmental and health risk when returning to normal amidst COVID-19 vaccination. CURRENT OPINION IN ENVIRONMENTAL SCIENCE & HEALTH 2022; 26:100328. [PMID: 35155880 PMCID: PMC8817624 DOI: 10.1016/j.coesh.2022.100328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Due to the SARS-CoV-2 pandemic and restricted occupancy in work and school settings, there is a heightened risk for Legionella infection. An increase of stagnation in water pipe systems with limited water usage stimulates biofilm build-up, further facilitating Legionella proliferation. Individuals can inhale infected water aerosols and develop Legionellosis that can progress into mild flu-like symptoms or severe pneumonia. While SARS-CoV-2 vaccinations have been introduced globally, there is a concern for bacterial coinfections as individuals resume normal activities. Even with new SARS-CoV-2 variants circulating, Legionella persists as a public health threat as vulnerable communities' restrictions fluctuate. Proper water monitoring and management are critical while reopening communities. This article features Legionella characteristics and novel case reports amidst the pandemic. This article encourages greater awareness for building managers to minimize water stagnancy by disinfecting water distribution systems and promotes healthcare professionals to properly diagnose other illnesses during the ongoing pandemic to reduce morbidity and mortality.
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Affiliation(s)
- Emma C Lancaster
- Division of Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, OH, USA
| | - Jiyoung Lee
- Division of Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, OH, USA
- Department of Food Science & Technology, The Ohio State University, Columbus, OH, USA
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Variable Legionella Response to Building Occupancy Patterns and Precautionary Flushing. Microorganisms 2022; 10:microorganisms10030555. [PMID: 35336130 PMCID: PMC8950775 DOI: 10.3390/microorganisms10030555] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 02/21/2022] [Accepted: 02/26/2022] [Indexed: 02/04/2023] Open
Abstract
When stay-at-home orders were issued to slow the spread of COVID-19, building occupancy (and water demand) was drastically decreased in many buildings. There was concern that widespread low water demand may cause unprecedented Legionella occurrence and Legionnaires’ disease incidence. In lieu of evidenced-based guidance, many people flushed their water systems as a preventative measure, using highly variable practices. Here, we present field-scale research from a building before, during, and after periods of low occupancy, and controlled stagnation experiments. We document no change, a > 4-log increase, and a > 1.5-log decrease of L. pneumophila during 3- to 7-week periods of low water demand. L. pneumophila increased by > 1-log after precautionary flushing prior to reoccupancy, which was repeated in controlled boiler flushing experiments. These results demonstrate that the impact of low water demand (colloquially called stagnation) is not as straight forward as is generally assumed, and that some flushing practices have potential unintended consequences. In particular, stagnation must be considered in context with other Legionella growth factors like temperature and flow profiles. Boiler flushing practices that dramatically increase the flow rate and rapidly deplete boiler temperature may mobilize Legionella present in biofilms and sediment.
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Montagnino E, Lytle DA, Rose J, Cwiertny D, Whelton AJ. School and childcare center drinking water: Copper chemistry, health effects, occurrence, and remediation. AWWA WATER SCIENCE 2022; 4:e1270. [PMID: 35865674 PMCID: PMC9286453 DOI: 10.1002/aws2.1270] [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: 10/17/2021] [Revised: 01/12/2022] [Accepted: 01/18/2022] [Indexed: 06/15/2023]
Abstract
The study goal was to better understand the risks of elevated copper levels at US schools and childcare centers. Copper health effects, chemistry, occurrence, and remediation actions were reviewed. Of the more than 98,000 schools and 500,000 childcare centers, only 0.2% had copper water testing data in the federal Safe Drinking Water Information System database. Of the facilities designated public water systems, about 13% had reported an exceedance. Schools that were not designated a public water system (PWS) also had exceedances. Few studies document levels in schools and childcare centers. Widely different sampling and remedial actions were reported. Flushing contaminated water was the most evaluated remedial action but was unreliable because copper quickly rebounded when flushing stopped. Building water treatment systems have been used, but some were not capable of making the water safe. The health risk was difficult to determine due to the limited occurrence data and lack of best management practice studies. A national drinking water testing campaign and field studies are recommended.
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Affiliation(s)
| | | | - Joan Rose
- Michigan State UniversityEast LansingMichiganUSA
| | - David Cwiertny
- Department of Civil and Environmental EngineeringUniversity of IowaIowa CityIowaUSA
- Center for Health Effects of Environmental ContaminationUniversity of IowaIowa CityIowaUSA
- Public Policy CenterUniversity of IowaIowa CityIowaUSA
| | - Andrew J. Whelton
- Lyles School of Civil Engineering and Division of Environmental and Ecological EngineeringPurdue UniversityWest LafayetteIndianaUSA
- Center for Plumbing SafetyPurdue UniversityWest LafayetteIndianaUSA
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33
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Proctor C, Garner E, Hamilton KA, Ashbolt NJ, Caverly LJ, Falkinham JO, Haas CN, Prevost M, Prevots DR, Pruden A, Raskin L, Stout J, Haig SJ. Tenets of a holistic approach to drinking water-associated pathogen research, management, and communication. WATER RESEARCH 2022; 211:117997. [PMID: 34999316 PMCID: PMC8821414 DOI: 10.1016/j.watres.2021.117997] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 12/13/2021] [Accepted: 12/19/2021] [Indexed: 05/10/2023]
Abstract
In recent years, drinking water-associated pathogens that can cause infections in immunocompromised or otherwise susceptible individuals (henceforth referred to as DWPI), sometimes referred to as opportunistic pathogens or opportunistic premise plumbing pathogens, have received considerable attention. DWPI research has largely been conducted by experts focusing on specific microorganisms or within silos of expertise. The resulting mitigation approaches optimized for a single microorganism may have unintended consequences and trade-offs for other DWPI or other interests (e.g., energy costs and conservation). For example, the ecological and epidemiological issues characteristic of Legionella pneumophila diverge from those relevant for Mycobacterium avium and other nontuberculous mycobacteria. Recent advances in understanding DWPI as part of a complex microbial ecosystem inhabiting drinking water systems continues to reveal additional challenges: namely, how can all microorganisms of concern be managed simultaneously? In order to protect public health, we must take a more holistic approach in all aspects of the field, including basic research, monitoring methods, risk-based mitigation techniques, and policy. A holistic approach will (i) target multiple microorganisms simultaneously, (ii) involve experts across several disciplines, and (iii) communicate results across disciplines and more broadly, proactively addressing source water-to-customer system management.
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Affiliation(s)
- Caitlin Proctor
- Department of Agricultural and Biological Engineering, Division of Environmental and Ecological Engineering, Purdue University, West Lafayette, IN, USA
| | - Emily Garner
- Wadsworth Department of Civil & Environmental Engineering, West Virginia University, Morgantown, WV, USA
| | - Kerry A Hamilton
- School of Sustainable Engineering and the Built Environment and The Biodesign Centre for Environmental Health Engineering, Arizona State University, Tempe, AZ, USA
| | - Nicholas J Ashbolt
- Faculty of Science and Engineering, Southern Cross University, Gold Coast. Queensland, Australia
| | - Lindsay J Caverly
- Department of Pediatrics, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - Charles N Haas
- Department of Civil, Architectural & Environmental Engineering, Drexel University, Philadelphia, PA, USA
| | - Michele Prevost
- Department of Civil, Geological and Mining Engineering, Polytechnique Montreal, Montreal, Quebec, Canada
| | - D Rebecca Prevots
- Epidemiology Unit, Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Amy Pruden
- Department of Civil & Environmental Engineering, Virginia Tech, Blacksburg, VA USA
| | - Lutgarde Raskin
- Department of Civil & Environmental Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Janet Stout
- Department of Civil & Environmental Engineering, University of Pittsburgh, and Special Pathogens Laboratory, Pittsburgh, PA, USA
| | - Sarah-Jane Haig
- Department of Civil & Environmental Engineering, and Department of Environmental & Occupational Health, University of Pittsburgh, Pittsburgh, PA, USA.
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Practitioners’ Perspective on the Prevalent Water Quality Management Practices for Legionella Control in Large Buildings in the United States. WATER 2022. [DOI: 10.3390/w14040663] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Managing building water systems is complicated by the need to maintain hot water temperatures high enough to control the growth of Legionella spp. while minimizing the risk of scalding. This study assessed water quality management practices in large buildings in the United States. Surveys conducted with building water quality managers found that more than 85% of buildings have hot water temperatures that are consistent with scald risk mitigation guidelines (i.e., <122 °F/50 °C). However, nearly two thirds and three quarters of buildings do not comply with the common temperature guidance for opportunistic pathogen control, i.e., water heater setpoint > 140 °F (60 °C) and recirculation loop > 122 °F (50 °C), respectively; median values for both setpoint and recirculation loop temperatures are 10 °F (6 °C) or more below temperatures recommended for opportunistic pathogen control. These observations suggest that many buildings are prone to Legionella spp. risk. The study also found that 27% of buildings do not comply with guidelines for time to equilibrium hot water temperature, over 33% fail to monitor temperature in the recirculation loop, more than 70% fail to replace or disinfect showerheads, more than 40% lack a written management plan, and only a minority conduct any monitoring of residual disinfectant levels or microbiological quality. Given the rise in Legionellosis infections in recent years, coupled with highlighted water quality concerns because of prolonged water stagnation in plumbing, such as in buildings closed due to COVID-19, current management practices, which appear to be focused on scald risk, may need to be broadened to include greater attention to control of opportunistic pathogens. To accomplish this, there is a need for formal training and resources for facility managers.
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Farhat N, Kim L, Mineta K, Alarawi M, Gojobori T, Saikaly P, Vrouwenvelder J. Seawater desalination based drinking water: Microbial characterization during distribution with and without residual chlorine. WATER RESEARCH 2022; 210:117975. [PMID: 34952456 DOI: 10.1016/j.watres.2021.117975] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 12/12/2021] [Accepted: 12/14/2021] [Indexed: 06/14/2023]
Abstract
Monitoring the changes that occur to water during distribution is vital to ensure water safety. In this study, the biological stability of reverse osmosis (RO) produced drinking water, characterized by low cell concentration and low assimilable organic carbon, in combination with chlorine disinfection was investigated. Water quality at several locations throughout the existing distribution network was monitored to investigate whether microbial water quality changes can be identified. Results revealed that the water leaving the plant had an average bacterial cell concentration of 103 cells/mL. A 0.5-1.5 log increase in bacterial cell concentration was observed at locations in the network. The residual disinfectant was largely dissipated in the network from 0.5 mg/L at the treatment plant to less than 0.1 mg/L in the network locations. The simulative study involving miniature distribution networks, mimicking the dynamics of a distribution network, fed with the RO produced chlorinated and non-chlorinated drinking water revealed that distributing RO produced water without residual disinfection, especially at high water temperatures (25-30 °C), poses a higher chance for water quality change. Within six months of operation of the miniature network fed with unchlorinated RO produced water, the adenosine triphosphate (ATP) and total cell concentration (TCC) in the pipe biofilm were 4 × 102 pg ATP/cm2 and 1 × 107 cells/ cm2. The low bacterial cell concentration and organic carbon concentration in the RO-produced water did not prevent biofilm development inside the network with and without residual chlorine. The bacterial community analysis using 16S ribosomal RNA (rRNA) gene sequencing revealed that mesophilic bacteria with higher temperature tolerance and bacteria associated with oligotrophic, nutrient-poor conditions dominated the biofilm, with no indication of the existence of opportunistic pathogenic species. However, chlorination selected against most bacterial groups and the bacterial community that remained was mainly the bacteria capable of surviving disinfection regimes. Biofilms that developed in the presence of chlorine contained species classified as opportunistic pathogens. These biofilms have an impact on shaping the water quality received at the consumer tap. The presence of these bacteria on its own is not a health risk indicator; viability assessment and qPCRs targeting genes specific to the opportunistic pathogens as well as quantitative microbiological risk assessment (QMRA) should be included to assess the risk. The results from this study highlight the importance of implementing multiple barriers to ensure water safety. Changes in water quality detected even when high-quality disinfected RO-produced water is distributed highlight microbiological challenges that chlorinated systems endure, especially at high water temperatures.
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Affiliation(s)
- Nadia Farhat
- Water Desalination and Reuse Center (WDRC), Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia.
| | - Lanhee Kim
- Water Desalination and Reuse Center (WDRC), Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Katsuhiko Mineta
- Computational Bioscience Research Center (CBRC), Division of Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Mohammed Alarawi
- Computational Bioscience Research Center (CBRC), Division of Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Takashi Gojobori
- Computational Bioscience Research Center (CBRC), Division of Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia; Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Pascal Saikaly
- Water Desalination and Reuse Center (WDRC), Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Johannes Vrouwenvelder
- Water Desalination and Reuse Center (WDRC), Division of Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia; Faculty of Applied Sciences, Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, Delft 2629 HZ, Netherlands
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36
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Pesantez JE, Alghamdi F, Sabu S, Mahinthakumar G, Berglund EZ. Using a digital twin to explore water infrastructure impacts during the COVID-19 pandemic. SUSTAINABLE CITIES AND SOCIETY 2022; 77:103520. [PMID: 34777984 PMCID: PMC8572083 DOI: 10.1016/j.scs.2021.103520] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 10/25/2021] [Accepted: 10/25/2021] [Indexed: 05/30/2023]
Abstract
During the coronavirus disease 2019 (COVID-19) pandemic, the daily pattern of activities changed dramatically for people across the globe, as they socially distanced and worked remotely. Changes in daily routines created changes in water consumption patterns. Significant changes in water demands can affect the operation of water distribution systems, resulting in new patterns of flow, with implications for water age, pressure, and energy consumption. This research develops a digital twin to couple Advanced Metering Infrastructure (AMI) data with a hydraulic model to assess impacts on infrastructure due to changes in water demands associated with the COVID-19 pandemic for a case study. Using 2019 and COVID-19 modeling scenarios, the hydraulic model was executed to evaluate changes to water quality based on water age, pressure across nodes in the network, and the energy required by the system to distribute potable water. A water supply interruption event was modeled as a water main break to assess network resiliency for 2019 and COVID-19 demands. A digital twin provides the capabilities to explore and visualize emerging consumption patterns and their effects on the functioning of water systems, providing valuable analyses for water utility managers and insight for optimizing infrastructure operations and planning for long-term impacts.
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Affiliation(s)
- Jorge E Pesantez
- Graduate Student, Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Raleigh, NC 27695, USA
| | - Faisal Alghamdi
- Graduate Student, Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Raleigh, NC 27695, USA
- Graduate Assistant, Department of Civil and Environmental Engineering, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Shreya Sabu
- Graduate Student, Department of Computer Science, North Carolina State University, Raleigh, NC 27695, USA
| | - G Mahinthakumar
- Professor, Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Raleigh, NC 27695, USA
| | - Emily Zechman Berglund
- Professor, Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Raleigh, NC 27695, USA
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37
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Bakchan A, Roy A, Faust KM. Impacts of COVID-19 social distancing policies on water demand: A population dynamics perspective. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 302:113949. [PMID: 34872171 PMCID: PMC8519786 DOI: 10.1016/j.jenvman.2021.113949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 09/15/2021] [Accepted: 10/14/2021] [Indexed: 06/13/2023]
Abstract
Social distancing policies (SDPs) implemented in response to the COVID-19 pandemic have led to temporal and spatial shifts in water demand across cities. Water utilities need to understand these demand shifts to respond to potential operational and water-quality issues. Aided by a fixed-effects model of citywide water demand in Austin, Texas, we explore the impacts of various SDPs (e.g., time after the stay home-work safe order, reopening phases) using daily demand data gathered between 2013 and 2020. Our approach uses socio-technical determinants (e.g., climate, water conservation policy) with SDPs to model water demand, while accounting for spatial and temporal effects (e.g., geographic variations, weekday patterns). Results indicate shifts in behavior of residential and nonresidential demands that offset the change at the system scale, demonstrating a spatial redistribution of water demand after the stay home-work safe order. Our results show that some phases of Texas's reopening phases had statistically significant relationships to water demand. While this yielded only marginal net effects on overall demand, it underscores behavioral changes in demand at sub-system spatial scales. Our discussions shed light on SDPs' impacts on water demand. Equipped with our empirical findings, utilities can respond to potential vulnerabilities in their systems, such as water-quality problems that may be related to changes in water pressure in response to demand variations.
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Affiliation(s)
- Amal Bakchan
- Civil, Architectural and Environmental Engineering, The University of Texas at Austin, 301 East Dean Keaton Street C1752, Austin, TX, 78712, United States.
| | - Arkajyoti Roy
- Management Science and Statistics, The University of Texas at San Antonio, One UTSA Cir., San Antonio, TX, 78249, United States.
| | - Kasey M Faust
- Civil, Architectural and Environmental Engineering, The University of Texas at Austin, 301 East Dean Keaton Street C1752, Austin, TX, 78712, United States.
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Salehi M. Global water shortage and potable water safety; Today's concern and tomorrow's crisis. ENVIRONMENT INTERNATIONAL 2022; 158:106936. [PMID: 34655888 DOI: 10.1016/j.envint.2021.106936] [Citation(s) in RCA: 78] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/10/2021] [Accepted: 10/11/2021] [Indexed: 05/28/2023]
Abstract
Climate change, severe droughts, population growth, demand increase, and poor management during the recent decades have further stressed the scarce freshwater resources worldwide and resulted in severe water shortages in many regions. The water utilities address the water shortage by providing alternative source of water, augment the supplied water, supply intermittently, and even bulk water delivery under severe water shortage conditions. On the other hand, many households store water in building storage tanks to cope with insufficient delivery of potable water due to frequent interruptions. All these practices could pose crucial risks to the chemical and microbiological quality of the water. However, consistent monitoring and implementation of mitigation strategies could lower the potential risks associated with these practices. It is critical to identify the potential hazards resulting from the alternative water supplies and distribution practices to develop temporary and long-term monitoring and mitigation plans and reduce the microbial and chemical contamination of potable water delivered to the consumers. This paper provides a holistic review of the significant hazards associated with the practices employed by the water utilities and water consumers to alleviate the potable water shortage and discusses the required monitoring and mitigation practices.
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Affiliation(s)
- Maryam Salehi
- Department of Civil Engineering, The University of Memphis, 3815 Central Avenue, 108C Engineering Science Bldg, Memphis, TN 38152, United States.
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39
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Richard R, Boyer TH. Pre- and post-flushing of three schools in Arizona due to COVID-19 shutdown. AWWA WATER SCIENCE 2021; 3:e1239. [PMID: 34901766 PMCID: PMC8646703 DOI: 10.1002/aws2.1239] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 08/03/2021] [Accepted: 08/11/2021] [Indexed: 01/14/2023]
Abstract
A one-day water sampling and flushing study was conducted for three schools in Maricopa County that experienced prolonged building inactivity due to the COVID-19 pandemic: an elementary school, middle school, and high school. Grab samples were taken at hand washing sinks, water fountains, and hose bibbs before and after flushing. Samples were analyzed for free chlorine, UVA254, copper, lead, total trihalomethanes, pH, conductivity, temperature, and Legionella species. All three schools experienced an increase in free chlorine post-flush. Copper concentrations were higher for first draw samples than post-flush samples for all schools. Conductivity, temperature, and pH did not see a major change after flushing. UVA254 values decreased after flushing. Bromoform species saw a 20% increase after flushing at the elementary school. Legionella spp. did not decrease post-flush at the elementary school. Overall, flushing changed the water quality at the schools. However, equipment flushing may be necessary to fully remediate Legionella spp. ARTICLE IMPACT STATEMENT Prolonged closure of buildings causes water quality issues such as lack of disinfectant and Legionella. Flushing can restore water quality.
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Affiliation(s)
- Rain Richard
- School of Sustainable Engineering and the Built Environment (SSEBE)Arizona State UniversityTempeArizonaUSA
- Biodesign Swette Center for Environmental BiotechnologyArizona State UniversityTempeArizonaUSA
| | - Treavor H. Boyer
- School of Sustainable Engineering and the Built Environment (SSEBE)Arizona State UniversityTempeArizonaUSA
- Biodesign Swette Center for Environmental BiotechnologyArizona State UniversityTempeArizonaUSA
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40
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Roy S, Mosteller K, Mosteller M, Webber K, Webber V, Webber S, Reid L, Walters L, Edwards MA. Citizen science chlorine surveillance during the Flint, Michigan federal water emergency. WATER RESEARCH 2021; 201:117304. [PMID: 34107367 DOI: 10.1016/j.watres.2021.117304] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 04/30/2021] [Accepted: 05/24/2021] [Indexed: 05/12/2023]
Abstract
Rising incidence of waterborne diseases including Legionellosis linked to low chlorine residuals in buildings and the availability of inexpensive testing options, create an opportunity for citizen science chorine monitoring to complement sampling done by water utilities. University researchers and Flint residents coordinated a citizen science chlorine surveillance campaign in Flint, Michigan in 2015-19, that helped expose the nature of two deadly Legionnaires Disease outbreaks in 2014-2015 during the Flint Water Crisis and progress of system recovery during the Federal emergency. Results obtained with an inexpensive color wheel were in agreement with a digital colorimeter (R2 =0.99; p = 2.81 × 10-21) at 15 sites geographically distributed across Flint. Blinded tests revealed good agreement between official (n = 2051) and citizen (n = 654) data in terms of determining whether regulatory guidelines for chlorine were met, but a discovery that the citizen data were statistically lower than the city's (p<0.00001) especially in warm summer months led to recommendations for increased flushing of service lines before measurements. This work suggests that expanded citizen surveillance of chlorine, site specific flushing advice, and guidance on decisions about water heater set point could help consumers reduce Legionella risks in their homes. Citizen science initiatives for chlorine monitoring offer a unique opportunity for mutually beneficial collaborations between consumers and utilities to reduce the main source of waterborne disease in developed countries.
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Affiliation(s)
- Siddhartha Roy
- Civil and Environmental Engineering, Virginia Tech, USA.
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41
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Ji B, Zhao Y, Wei T, Kang P. Water science under the global epidemic of COVID-19: Bibliometric tracking on COVID-19 publication and further research needs. JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING 2021; 9:105357. [PMID: 33747765 PMCID: PMC7959687 DOI: 10.1016/j.jece.2021.105357] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/22/2021] [Accepted: 03/12/2021] [Indexed: 05/05/2023]
Abstract
There are overwhelming increases of studies and over 200,000 publications related to all the aspects of COVID-19. Among them, 262 papers were published by authors from 67 countries regarding COVID-19 with water science and technology. Although the transmission routes of SARS-CoV-2 in water cycle have not been proved, the water and wastewater play an important role in the control of COVID-19 pandemic. Accordingly, it is scholarly relevant and interesting to look into publications of COVID-19 in water science and technology to track the investigations for moving forward in the years to come. It is believed that, through the literature survey, the question on what we know and what we do not know about COVID-19 so far can be clear, thus providing useful information for helping curbing the epidemic from water sector. This forms the basis of the current study. As such, a bibliometric analysis was conducted. It reveals that wastewater-based epidemiology (WBE) has recently gained global attention with the source and survival characteristics of coronavirus in the aquatic environment; the methodology of virus detection; the water hygiene; and the impact of the COVID-19 pandemic on the water ecosystem being the main topics in 2020. Various studies have shown that drinking water is safety whereas wastewater may be a potential risk during this pandemic. From the perspective of the water cycle, the scopes for further research needs are discussed and proposed, which could enhance the important role and value of water science in warning, monitoring, and predicting COVID-19 during epidemic outbreaks.
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Affiliation(s)
- Bin Ji
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an 710048, PR China
- Department of Municipal and Environmental Engineering, Faculty of Water Resources and Hydroelectric Engineering, Xi'an University of Technology, Xi'an 710048, PR China
| | - Yaqian Zhao
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an 710048, PR China
- Department of Municipal and Environmental Engineering, Faculty of Water Resources and Hydroelectric Engineering, Xi'an University of Technology, Xi'an 710048, PR China
| | - Ting Wei
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an 710048, PR China
- Chemical Engineering Department, University of Alcalá, Madrid, Spain
| | - Peiying Kang
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an 710048, PR China
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Hamilton KA, Kuppravalli A, Heida A, Joshi S, Haas CN, Verhougstraete M, Gerrity D. Legionnaires' disease in dental offices: Quantifying aerosol risks to dental workers and patients. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2021; 18:378-393. [PMID: 34161202 DOI: 10.1080/15459624.2021.1939878] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Legionella pneumophila is an opportunistic bacterial respiratory pathogen that is one of the leading causes of drinking water outbreaks in the United States. Dental offices pose a potential risk for inhalation or aspiration of L. pneumophila due to the high surface area to volume ratio of dental unit water lines-a feature that is conducive to biofilm growth. This is coupled with the use of high-pressure water devices (e.g., ultrasonic scalers) that produce fine aerosols within the breathing zone. Prior research confirms that L. pneumophila occurs in dental unit water lines, but the associated human health risks have not been assessed. We aimed to: (1) synthesize the evidence for transmission and management of Legionnaires' disease in dental offices; (2) create a quantitative modeling framework for predicting associated L. pneumophila infection risk; and (3) highlight influential parameters and research gaps requiring further study. We reviewed outbreaks, management guidance, and exposure studies and used these data to parameterize a quantitative microbial risk assessment (QMRA) model for L. pneumophila in dental applications. Probabilities of infection for dental hygienists and patients were assessed on a per-exposure and annual basis. We also assessed the impact of varying ventilation rates and the use of personal protective equipment (PPE). Following an instrument purge (i.e., flush) and with a ventilation rate of 1.2 air changes per hour, the median per-exposure probability of infection for dental hygienists and patients exceeded a 1-in-10,000 infection risk benchmark. Per-exposure risks for workers during a purge and annual risks for workers wearing N95 masks did not exceed the benchmark. Increasing air change rates in the treatment room from 1.2 to 10 would achieve an ∼85% risk reduction, while utilization of N95 respirators would reduce risks by ∼95%. The concentration of L. pneumophila in dental unit water lines was a dominant parameter in the model and driver of risk. Future risk assessment efforts and refinement of microbiological control protocols would benefit from expanded occurrence datasets for L. pneumophila in dental applications.
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Affiliation(s)
- Kerry A Hamilton
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona
- The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, Tempe, Arizona
| | - Aditya Kuppravalli
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona
- The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, Tempe, Arizona
- BASIS Scottsdale High School, Scottsdale, Arizona
| | - Ashley Heida
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona
- The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, Tempe, Arizona
| | - Sayalee Joshi
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona
- The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, Tempe, Arizona
| | - Charles N Haas
- Department of Civil, Architectural, and Environmental Engineering, Drexel University, Philadelphia, Pennsylvania
| | - Marc Verhougstraete
- Mel and Enid Zuckerman College of Public Health, The University of Arizona, Tucson, Arizona
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Causes, Factors, and Control Measures of Opportunistic Premise Plumbing Pathogens—A Critical Review. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11104474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This review critically analyses the chemical and physical parameters that influence the occurrence of opportunistic pathogens in the drinking water distribution system, specifically in premise plumbing. A comprehensive literature review reveals significant impacts of water age, disinfectant residual (type and concentration), temperature, pH, and pipe materials. Evidence suggests that there is substantial interplay between these parameters; however, the dynamics of such relationships is yet to be elucidated. There is a correlation between premise plumbing system characteristics, including those featuring water and energy conservation measures, and increased water quality issues and public health concerns. Other interconnected issues exacerbated by high water age, such as disinfectant decay and reduced corrosion control efficiency, deserve closer attention. Some common features and trends in the occurrence of opportunistic pathogens have been identified through a thorough analysis of the available literature. It is proposed that the efforts to reduce or eliminate their incidence might best focus on these common features.
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Closed Genome and Plasmid Sequences of Legionella pneumophila AW-13-4, Isolated from a Hot Water Loop System of a Large Occupational Building. Microbiol Resour Announc 2021; 10:10/1/e01276-20. [PMID: 33414354 PMCID: PMC8407730 DOI: 10.1128/mra.01276-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Unused water in unoccupied buildings can become stagnant, with reductions in temperature and levels of disinfectant resulting in increased microbial growth. We report the closed and complete genome and plasmid of Legionella pneumophila strain AW-13-4 (serogroup 1), which was isolated from a hot water loop system of a large building.
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Cassell K, Davis JL, Berkelman R. Legionnaires' disease in the time of COVID-19. Pneumonia (Nathan) 2021; 13:2. [PMID: 33407911 PMCID: PMC7787226 DOI: 10.1186/s41479-020-00080-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 12/20/2020] [Indexed: 11/26/2022] Open
Abstract
Due to similarities in initial disease presentation, clinicians may be inclined to repeatedly test community-acquired pneumonia cases for COVID-19 before recognizing the need to test for Legionnaires' disease. Legionnaires' disease is an illness characterized by pneumonia that has a summer/early fall seasonality due to favorable conditions for Legionella growth and exposure. Legionella proliferate in warm water environments and stagnant sections of indoor plumbing and cooling systems. During the ongoing pandemic crisis, exposures to aerosolized water from recently reopened office or retail buildings should be considered as an epidemiologic risk factor for Legionella exposure and an indication to test. The majority of Legionnaires' disease cases occurring each year are not diagnosed, and some experts recommend that all patients hospitalized with community-acquired pneumonia without a known etiology be tested for Legionella infection. Proper diagnosis can increase the likelihood of appropriate and timely antibiotic treatment, identify potential clusters of disease, and facilitate source attribution.
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Affiliation(s)
- Kelsie Cassell
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA.
| | - J Lucian Davis
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA
- Pulmonary, Critical Care, and Sleep Medicine Section, Yale School of Medicine, New Haven, CT, USA
| | - Ruth Berkelman
- Rollins School of Public Health, Emory University, Atlanta, GA, USA
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Triantafyllidou S, Burkhardt J, Tully J, Cahalan K, DeSantis M, Lytle D, Schock M. Variability and sampling of lead (Pb) in drinking water: Assessing potential human exposure depends on the sampling protocol. ENVIRONMENT INTERNATIONAL 2021; 146:106259. [PMID: 33395926 PMCID: PMC7879988 DOI: 10.1016/j.envint.2020.106259] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 10/30/2020] [Accepted: 10/31/2020] [Indexed: 05/27/2023]
Abstract
Lead (Pb) in drinking water has re-emerged as a modern public health threat which can vary widely in space and in time (i.e., between homes, within homes and even at the same tap over time). Spatial and temporal water Pb variability in buildings is the combined result of water chemistry, hydraulics, Pb plumbing materials and water use patterns. This makes it challenging to obtain meaningful water Pb data with which to estimate potential exposure to residents. The objectives of this review paper are to describe the root causes of intrinsic Pb variability in drinking water, which in turn impacts the numerous existing water sampling protocols for Pb. Such knowledge can assist the public health community, the drinking water industry, and other interested groups to interpret/compare existing drinking water Pb data, develop appropriate sampling protocols to answer specific questions relating to Pb in water, and understand potential exposure to Pb-contaminated water. Overall, review of the literature indicated that drinking water sampling for Pb assessment can serve many purposes. Regulatory compliance sampling protocols are useful in assessing community-wide compliance with a water Pb regulatory standard by typically employing practical single samples. More complex multi-sample protocols are useful for comprehensive Pb plumbing source determination (e.g., Pb service line, Pb brass faucet, Pb solder joint) or Pb form identification (i.e., particulate Pb release) in buildings. Exposure assessment sampling can employ cumulative water samples that directly capture an approximate average water Pb concentration over a prolonged period of normal household water use. Exposure assessment may conceivably also employ frequent random single samples, but this approach warrants further investigation. Each protocol has a specific use answering one or more questions relevant to Pb in water. In order to establish statistical correlations to blood Pb measurements or to predict blood Pb levels from existing datasets, the suitability of available drinking water Pb datasets in representing water Pb exposure needs to be understood and the uncertainties need to be characterized.
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Affiliation(s)
- Simoni Triantafyllidou
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions & Emergency Response, Water Infrastructure Division, 26 W. Martin Luther King Dr., Cincinnati, OH, United States.
| | - Jonathan Burkhardt
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions & Emergency Response, Water Infrastructure Division, 26 W. Martin Luther King Dr., Cincinnati, OH, United States
| | - Jennifer Tully
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions & Emergency Response, Water Infrastructure Division, 26 W. Martin Luther King Dr., Cincinnati, OH, United States
| | - Kelly Cahalan
- Oak Ridge Associated Universities at Time of This Work, Currently New York City Department of Environmental Protection, Bureau of Water Supply, Distribution Science and Planning, New York City, NY, United States
| | - Michael DeSantis
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions & Emergency Response, Water Infrastructure Division, 26 W. Martin Luther King Dr., Cincinnati, OH, United States
| | - Darren Lytle
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions & Emergency Response, Water Infrastructure Division, 26 W. Martin Luther King Dr., Cincinnati, OH, United States
| | - Michael Schock
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Solutions & Emergency Response, Water Infrastructure Division, 26 W. Martin Luther King Dr., Cincinnati, OH, United States
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Gude VG, Muire PJ. Preparing for outbreaks - Implications for resilient water utility operations and services. SUSTAINABLE CITIES AND SOCIETY 2021; 64:102558. [PMID: 33101881 PMCID: PMC7572320 DOI: 10.1016/j.scs.2020.102558] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 10/01/2020] [Accepted: 10/13/2020] [Indexed: 05/21/2023]
Abstract
Recent outbreaks have constantly disrupted our global economy and public health in numerous ways, impacting efficiency and prosperity across all sectors. This article focuses on the impacts of outbreaks (epidemics and pandemics) on water - wastewater utilities and water infrastructure and critically evaluates the issues underlining their impact on economic development and highlights the need for preparedness. A perspective on water infrastructure and industry-related impact on our society and economic development in the wake of the pandemic, COVID-19, is presented. Methods that could potentially institute safe, reliable, and efficient procedures for better preparedness and rapid recovery have been explored at length. The purpose of this article is therefore threefold: 1) to discuss the economic and public health impact of outbreaks on water and wastewater utilities and utility workforce; 2) to present case studies demonstrating utilities' preparedness and response to COVID-19, and 3) to review various alternatives for education and training as well as innovative processes and strategies for productivity during and after outbreaks. Strategies discussed in this article could be used as valuable tools for developing resiliency efforts, especially from the context of continuing water and wastewater utility operations and services in emergencies.
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Affiliation(s)
- Veera Gnaneswar Gude
- Department of Civil and Environmental Engineering, Mississippi State University, MS 39762, United States
| | - Preeti J Muire
- US Army Institute of Surgical Research, Fort Sam Houston, TX 78219, United States
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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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Cullom AC, Martin RL, Song Y, Williams K, Williams A, Pruden A, Edwards MA. Critical Review: Propensity of Premise Plumbing Pipe Materials to Enhance or Diminish Growth of Legionella and Other Opportunistic Pathogens. Pathogens 2020; 9:E957. [PMID: 33212943 PMCID: PMC7698398 DOI: 10.3390/pathogens9110957] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/12/2020] [Accepted: 11/13/2020] [Indexed: 12/20/2022] Open
Abstract
Growth of Legionella pneumophila and other opportunistic pathogens (OPs) in drinking water premise plumbing poses an increasing public health concern. Premise plumbing is constructed of a variety of materials, creating complex environments that vary chemically, microbiologically, spatially, and temporally in a manner likely to influence survival and growth of OPs. Here we systematically review the literature to critically examine the varied effects of common metallic (copper, iron) and plastic (PVC, cross-linked polyethylene (PEX)) pipe materials on factors influencing OP growth in drinking water, including nutrient availability, disinfectant levels, and the composition of the broader microbiome. Plastic pipes can leach organic carbon, but demonstrate a lower disinfectant demand and fewer water chemistry interactions. Iron pipes may provide OPs with nutrients directly or indirectly, exhibiting a high disinfectant demand and potential to form scales with high surface areas suitable for biofilm colonization. While copper pipes are known for their antimicrobial properties, evidence of their efficacy for OP control is inconsistent. Under some circumstances, copper's interactions with premise plumbing water chemistry and resident microbes can encourage growth of OPs. Plumbing design, configuration, and operation can be manipulated to control such interactions and health outcomes. Influences of pipe materials on OP physiology should also be considered, including the possibility of influencing virulence and antibiotic resistance. In conclusion, all known pipe materials have a potential to either stimulate or inhibit OP growth, depending on the circumstances. This review delineates some of these circumstances and informs future research and guidance towards effective deployment of pipe materials for control of OPs.
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Affiliation(s)
- Abraham C. Cullom
- Civil and Environmental Engineering, Virginia Tech, 1145 Perry St., 418 Durham Hall, Blacksburg, VA 24061, USA; (A.C.C.); (R.L.M.); (Y.S.); (A.P.)
| | - Rebekah L. Martin
- Civil and Environmental Engineering, Virginia Tech, 1145 Perry St., 418 Durham Hall, Blacksburg, VA 24061, USA; (A.C.C.); (R.L.M.); (Y.S.); (A.P.)
- Civil and Environmental Engineering, Virginia Military Institute, Lexington, VA 24450, USA
| | - Yang Song
- Civil and Environmental Engineering, Virginia Tech, 1145 Perry St., 418 Durham Hall, Blacksburg, VA 24061, USA; (A.C.C.); (R.L.M.); (Y.S.); (A.P.)
| | | | - Amanda Williams
- c/o Marc Edwards, Civil and Environmental Engineering, Virginia Tech, 1145 Perry St., 418 Durham Hall, Blacksburg, VA 24061, USA;
| | - Amy Pruden
- Civil and Environmental Engineering, Virginia Tech, 1145 Perry St., 418 Durham Hall, Blacksburg, VA 24061, USA; (A.C.C.); (R.L.M.); (Y.S.); (A.P.)
| | - Marc A. Edwards
- Civil and Environmental Engineering, Virginia Tech, 1145 Perry St., 418 Durham Hall, Blacksburg, VA 24061, USA; (A.C.C.); (R.L.M.); (Y.S.); (A.P.)
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50
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Prediction of Children’s Blood Lead Levels from Exposure to Lead in Schools’ Drinking Water—A Case Study in Tennessee, USA. WATER 2020. [DOI: 10.3390/w12061826] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Lead (Pb) exposure can delay children’s mental development and cause behavioral disorders and IQ deficits. With children spending a significant portion of their time at schools, it is critical to investigate the lead concentration in schools’ drinking water to prevent children’s exposure. The objectives of this work were to predict students’ geometric mean (GM) blood lead levels (BLLs), the fractions of at-risk students (those with BLLs > 5 μg/dL), and the total number of at-risk students in one Tennessee school district. School drinking water lead concentration data collected in 2019 were input into the Integrated Exposure Uptake Biokinetic (IEUBK) model and the Bowers’ model to predict BLLs for elementary school students and secondary school students, respectively. Sensitivity analyses were conducted for both models. Drinking water concentrations were qualitatively compared with data collected in 2017. Two scenarios were evaluated for each model to provide upper and median estimates. The weighted GM BLL upper and median estimates for elementary school students were 2.35 μg/dL and 0.99 μg/dL, respectively. This equated to an upper estimate of 1300 elementary school students (5.8%) and a median estimate of 140 elementary school students (0.6%) being at risk of elevated BLLs. Similarly, the weighted GM BLL upper and median estimates for secondary school students were 2.99 μg/dL and 1.53 μg/dL, respectively, and equated to an upper estimate of 6900 secondary school students (13.6%) and a median estimate of 300 secondary school students (0.6%) being at risk of elevated BLLs. Drinking water remediation efforts are recommended for schools exhibiting water lead concentrations greater than 15 μg/L. Site-specific soil lead concentration data are recommended since the IEUBK was deemed sensitive to soil lead concentrations. For this reason, soil lead remediation may have a greater impact on lowering children’s BLLs than drinking water lead remediation. Remediation efforts are especially vital at elementary schools to reduce the population’s baseline BLL and thus the BLL projected by Bowers’ model.
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