Hydrogen Gas Inhalation Shows No DNA Damage Risk in Safety Study
- Authors
- Cordelia Salomez-Ihl, Stephane Tanguy, Jean-Pierre Alcaraz, Chloe Davin, Victor Pascal-Moussellard, Mariem Jabeur, Pierrick Bedouch, Ludovic Le Hegarat, Valerie Fessard, Anne-Louise Blier, Huet Sylvie, Philippe Cinquin, Francois Boucher
- Journal
- Mutation Research. Genetic Toxicology and Environmental Mutagenesis
- Year
- 2024
- DOI
- 10.1016/j.mrgentox.2024.503736
- Study Type
- Rat
- Outcome
- Neutral
- Peer Reviewed
- Yes
- Country
- France
- Health Condition
- Genetic Toxicity Assessment
- Body System
- Respiratory
TL;DR
Breathing in a mixture of 3.1% hydrogen gas for 72 hours did not cause genetic damage in rats.
Key Finding
Rats exposed to 3.1% hydrogen gas for 72 hours showed no signs of genetic damage (genotoxicity) in blood, liver, or lung tissue across multiple standardized tests.
Summary
Researchers tested whether inhaling hydrogen gas could damage DNA in rats. Male rats breathed a mixture containing 3.1% hydrogen gas for 72 hours, and scientists examined their blood, liver, and lungs for signs of genetic damage using three different laboratory tests. The hydrogen-exposed rats showed no DNA damage or genetic abnormalities compared to control animals.
Practical Takeaway
This animal study suggests that short-term hydrogen gas inhalation at the tested concentration does not cause detectable genetic damage in rats. However, this is a preclinical study in animals only—it does not directly demonstrate safety in humans, and longer-term exposure effects remain unstudied. More research, including human trials, would be needed before drawing conclusions about hydrogen inhalation safety for people.
Abstract
Preclinical and clinical studies have shown that molecular hydrogen (H2) has anti-oxidant, anti-inflammatory, and anti-apoptotic properties. Safety data are available in the literature and acute toxicity has been tested in isolated cells and laboratory animals. We have evaluates the genotoxicity of H2 in vivo in rats after 72 h exposure, following the International Council for Harmonization guidelines ICH S2 (R1). The study was conducted on three groups of male Wistar rats: a negative control group, a positive control group receiving methyl methanesulfonate, and a H2-treated group receiving a 3.1% H2 gas mixture for 72 h. Alkaline comet, formamidopyrimidine DNA glycosylase (Fpg)-modified comet and bone marrow micronucleus assays were performed. H2 exposure increased neither comet-tail DNA intensity (DNA damage) nor frequency of “hedgehogs” in blood, liver, lungs, or bronchoalveolar lavage fluid. No increase in Fpg-sensitive sites in lungs, no induction of micronucleus formation, and no imbalance of immature erythrocyte to total erythrocyte ratio (IME%) was observed in rats exposed to H2. The ICH S2 (R1) test-battery revealed no in vivo genotoxicity in Wistar rats after 72 h inhalation of a mixture containing 3.1% H2.