Hydrogen Water Loses Antimicrobial Power Over Time, Study Finds
- Authors
- Angelica Luevanos-Aguilera
- Journal
- Microbial Drug Resistance
- Year
- 2025
- DOI
- 10.1089/mdr.2024.0213
- Study Type
- Cell Culture
- Outcome
- Positive
- Peer Reviewed
- Yes
- Country
- Mexico
- Health Condition
- Wound Infections
- Body System
- Integumentary
TL;DR
The study found that the germ-killing power of electrolyzed water and chlorine-based disinfectants decreases over time, especially when they lose their chlorine content.
Key Finding
Electrolyzed water's ability to kill bacteria depends critically on maintaining free chlorine levels, and disinfectants with alkaline pH remain more stable and effective over time than those with neutral or acidic pH.
Summary
Researchers tested how well electrolyzed water (water treated with electricity) and chlorine-based disinfectants kill bacteria, and how their effectiveness changes over time when stored at warm temperatures. They found that these disinfectants work best when they contain higher levels of free chlorine (the active antimicrobial ingredient) and maintain an alkaline (basic) pH, but they gradually lose their killing power as the free chlorine breaks down during storage.
Practical Takeaway
This laboratory study suggests that electrolyzed water products used for disinfection may lose effectiveness during storage as their active ingredients degrade. However, this research tested disinfectant properties in controlled lab conditions using bacteria cultures—not in actual wound care or on human skin—so the findings may not directly translate to real-world use. The results indicate that storage conditions and formulation matter significantly for maintaining disinfectant potency.
Abstract
This study evaluated the antimicrobial efficacy of electrolyzed water (EW) and chlorine-based disinfectant (CLD) over time, focusing on the impact of pH, free chlorine (FCL), and oxidation-reduction potential (ORP). EW and CLD are commonly used for wound care and surgical instrument disinfection, but their chemical instability limits their use. The study was conducted in the Microbiology Laboratory of the University of Guanajuato, using Escherichia coli ATCC 25922 as the test organism. Disinfectants were maintained at 40°C, with systematic monitoring of pH, FCL, and ORP. Minimum bactericidal concentration was used to assess antimicrobial activity before and after thermal exposure. Statistical analyses included Kruskal-Wallis one-way ANOVA, and the Friedman test. Results showed that the antimicrobial activity of EW depended on FCL concentration, with a significant correlation between the absence of FCL and increased minimum bactericidal concentration (p < 0.01). Disinfectants with alkaline pH demonstrated greater stability over time (p < 0.01). The findings highlight the importance of FCL, pH, and ORP in the effectiveness of these disinfectants and underscore their limitations due to chemical instability in clinical settings.