Hydrogen Gas Inhalation Proves Safe in 72-Hour Mouse Safety Study
- Authors
- JohnN Kheir, AlexisR Cole, Ali Raza, Humera Ahmed, BrianD Polizzotti, RobertF Padera, Nick Andrews
- Journal
- Medical Gas Research
- Year
- 2019
- DOI
- 10.4103/2045-9912.266988
- Study Type
- Mouse
- Outcome
- Positive
- Peer Reviewed
- Yes
- Country
- United States
- Health Condition
- General Health
- Body System
- Whole Body
TL;DR
Inhaling hydrogen gas for 72 hours was found to be safe for healthy mice, except for a possible decrease in their spontaneous movement.
Key Finding
Inhaled hydrogen gas at 2.27% concentration appeared safe in healthy mice over 72 hours, with no damage to organs or abnormal blood work, though treated mice showed decreased spontaneous movement.
Summary
Researchers exposed healthy female mice to inhaled hydrogen gas (at about 2.4% concentration) for 72 hours to test whether it was safe. They checked the mice's behavior, blood work, and organ tissue under a microscope before and after exposure. The mice breathing hydrogen gas showed no significant problems with weight, organ damage, or blood chemistry, though they were slightly less active than control mice.
Practical Takeaway
This early animal study suggests inhaled hydrogen gas may be tolerable at this concentration, but it is limited to a short 72-hour exposure in mice. Much longer studies and human trials would be needed before any conclusions could be drawn about safety in people. The decrease in activity in hydrogen-treated mice also warrants further investigation.
Abstract
The purpose of this work was to determine the safety of inhaled hydrogen gas in healthy animals. Female mice were exposed to medical air with or without hydrogen gas (concentration 2.4%) for 72 hours (n = 25 mice/group). Mice underwent a standardized and validated neurobehavioral examination, SmithKline Beecham, Harwell, Imperial College, Royal London Hospital, Phenotype Assessment (SHIRPA) protocol, prior to and following the exposure period. Blood was withdrawn for serologic evaluation and all major organ tissues were evaluated histologically. The average hydrogen concentration within the chamber was 2.27%. Following exposure, there was no significant change in body weight in either group. Similarly, there was no significant change in the total SHIRPA score, although hydrogen-treated mice exhibited significantly lower spontaneous locomotor activity (P 0.05 for all). Hydrogen gas did not appear to cause significant adverse effects when administered to healthy mice for 72 hours, with the possible exception of decreased spontaneous locomotor activity. The study was approved by the Institutional Animal Care and Use Committee at Boston Children's Hospital, USA (approved number 18-01-3536) on January 25, 2018.