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Abstract Reductions in nonresidential water demand during the COVID-19 pandemic highlighted the importance of understanding how water age impacts drinking water quality and microbiota in piped distribution systems. Using benchtop model distribution systems, we aimed to characterize the impacts of elevated water age on microbiota in bulk water and pipe wall biofilms. Five replicate constant-flow reactors were fed with municipal chloraminated tap water for 6 months prior to building closures and 7 months after. After building closures, chloramine levels entering the reactors dropped; in the reactor bulk water and biofilms the mean cell counts and ATP concentrations increased over an order of magnitude while the detection of opportunistic pathogens remained low. Water age, and the corresponding physicochemical changes, strongly influenced microbial abundance and community composition. Differential initial microbial colonization also had a lasting influence on microbial communities in each reactor (i.e., historical contingency).
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Linkage of in-refrigerator water dispensing systems to elevated exposure to microbial contamination at the microbiome scale
In-refrigerator water dispensing systems are ubiquitous in residential homes with tap water as the inflow. Passage through these systems resulted in significant microbial growth in the water, with the abundance of potential opportunistic pathogens Mycobacterium and Pseudomonas increasing by 8,053- and 221-fold, respectively. Elevated exposure to microbial contaminants linked to in-refrigerator water dispensing systems may represent a significant public health concern.
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- Award ID(s):
- 2025339
- PAR ID:
- 10544828
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- American Journal of Infection Control
- Volume:
- 52
- Issue:
- 7
- ISSN:
- 0196-6553
- Page Range / eLocation ID:
- 857 to 859
- Subject(s) / Keyword(s):
- Mycobacterium Pseudomonas Drinking water Premise plumbing Point of use Filter
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.ajic.2024.03.001
