Microbiological quality of drinking water from water dispensers

Thomas D. Hile; Raeann Leal; Stephen G. Dunbar; Ryan G. Sinclair; Thomas D. Hile; Raeann Leal; Stephen G. Dunbar; Ryan G. Sinclair

doi:10.3934/microbiol.2025039

AIMS Microbiology

2025, Volume 11, Issue 4: 891-914. doi: 10.3934/microbiol.2025039

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Review

Microbiological quality of drinking water from water dispensers

1.
School of Science and Health, Crafton Hills College, Yucaipa, CA 92399, USA
2.
Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
3.
Marine Research Group, Loma Linda University, CA 92350 USA
4.
School of Public Health, Loma Linda University, Loma Linda, CA 92350, USA

Received: 15 April 2025 Revised: 01 December 2025 Accepted: 05 December 2025 Published: 11 December 2025

The consumption of drinking water from sources other than tap water, such as bottled water or water dispenser (WD) machines, is increasing worldwide, driven by consumer preferences for health, convenience, and taste. This trend raises concerns about potential microbial contamination and associated public health risks. In this review, we aimed to comprehensively analyze the scientific literature on microbial contamination in water dispenser machines, evaluate the quality of dispensed water, identify sources of contamination and potential health implications, and propose solutions to mitigate these risks. We conducted a comprehensive search of scientific databases, including PubMed, EBSCO, and Google Scholar, using relevant keywords related to water dispenser contamination. Abstracts and methods of identified studies were critically appraised to ensure rigorous assessment of microbial contamination. Our analysis of approximately 70 studies revealed that despite consumer perceptions of health benefits, water dispenser machines can harbor higher levels of microbial contamination than the tap water sources supplying them. This review underscores the potential public health risks associated with water dispenser use, and highlights the need for increased vigilance, regular maintenance, and further research to ensure the safety of dispensed water.
- contaminants,
- disadvantaged communities,
- outbreaks,
- microorganisms,
- water-borne diseases
Citation: Thomas D. Hile, Raeann Leal, Stephen G. Dunbar, Ryan G. Sinclair. Microbiological quality of drinking water from water dispensers[J]. AIMS Microbiology, 2025, 11(4): 891-914. doi: 10.3934/microbiol.2025039

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Abstract

The consumption of drinking water from sources other than tap water, such as bottled water or water dispenser (WD) machines, is increasing worldwide, driven by consumer preferences for health, convenience, and taste. This trend raises concerns about potential microbial contamination and associated public health risks. In this review, we aimed to comprehensively analyze the scientific literature on microbial contamination in water dispenser machines, evaluate the quality of dispensed water, identify sources of contamination and potential health implications, and propose solutions to mitigate these risks. We conducted a comprehensive search of scientific databases, including PubMed, EBSCO, and Google Scholar, using relevant keywords related to water dispenser contamination. Abstracts and methods of identified studies were critically appraised to ensure rigorous assessment of microbial contamination. Our analysis of approximately 70 studies revealed that despite consumer perceptions of health benefits, water dispenser machines can harbor higher levels of microbial contamination than the tap water sources supplying them. This review underscores the potential public health risks associated with water dispenser use, and highlights the need for increased vigilance, regular maintenance, and further research to ensure the safety of dispensed water.

Conflict of interest

All authors declare the have no conflicts of interest in this paper.

Author contributions

Thomas Hile designed the study, conducted the research, and wrote the initial draft of the review. Raeann Leal compiled and completed the tables and contributed to the editing of the manuscript. Ryan Sinclair reviewed and edited the introduction, methods, results, and discussion sections. Stephen G. Dunbar provided editorial input on the abstract, discussion, recommendations, and overall structure of the review. All authors reviewed and approved the final manuscript.

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