# Molecular hydrogen and radiation protection.
> 分子状水素と放射線防護：選択的抗酸化作用を中心としたレビュー


## Abstract

Molecular hydrogen (H₂) functions as a selective antioxidant capable of neutralizing hydroxyl radicals (•OH) and peroxynitrite (ONOO⁻). Ionizing radiation (IR) generates •OH through radiolysis of water, leading to oxidative cellular damage and subsequent apoptosis. This review consolidates findings from irradiated cell cultures and multiple animal model experiments demonstrating H₂-mediated radioprotection, including the authors' initial reports. Additionally, a randomized, placebo-controlled clinical study in patients undergoing radiotherapy for liver tumors showed that H₂ consumption was associated with improved quality of life. Collectively, these findings indicate that H₂ holds promise as a non-toxic radioprotective agent with demonstrable efficacy across experimental and clinical settings.

### Mechanism

H₂ selectively scavenges hydroxyl radicals and peroxynitrite generated by radiolysis of water during ionizing radiation exposure, thereby reducing oxidative damage and apoptosis in irradiated cells and tissues.

## Bibliographic

- **Authors**: Chuai Y, Qian L, Sun X, Cai J
- **Journal**: Free Radic Res
- **Year**: 2012
- **PMID**: [22537465](https://pubmed.ncbi.nlm.nih.gov/22537465/)
- **DOI**: [10.3109/10715762.2012.689429](https://doi.org/10.3109/10715762.2012.689429)
- **Study type**: review
- **Delivery route**: mixed routes
- **Effect reported**: positive

## Delivery context

This study combines multiple delivery routes. As a general principle, the most efficient route for routine hydrogen intake is inhalation. Inhalation carries explosion risk (empirical LFL of 10%; high-concentration devices are documented in the Consumer Affairs Agency accident database and are not recommended).

## Safety notes

This study combines multiple delivery routes. As a general principle, the most efficient route for routine hydrogen intake is inhalation. Inhalation carries explosion risk (empirical LFL of 10%; high-concentration devices are documented in the Consumer Affairs Agency accident database and are not recommended).

See also:
- [Inhalation concentration and LFL / UFL](https://h2-papers.org/en/safety-notes/inhalation-concentration)
- [Consumer Affairs Agency accident cases](https://h2-papers.org/en/safety-notes/accident-cases)
- [Inhalation safety threshold lineage](https://h2-papers.org/en/safety-notes/lineage)

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> **Cite as**: H2 Papers — PMID 22537465. https://h2-papers.org/en/papers/22537465
> **Source**: PubMed PMID [22537465](https://pubmed.ncbi.nlm.nih.gov/22537465/)