# Molecular hydrogen in agriculture.
> 農業における分子状水素の役割：植物ストレス耐性と生産性向上への応用


## Abstract

This review examines the expanding body of research on molecular hydrogen (H₂) as an agricultural tool. H₂, commonly delivered via hydrogen-saturated water, has been shown to alleviate multiple plant stresses, including salinity, heavy metal exposure, and drought conditions. Beyond stress mitigation, H₂ application is associated with improvements in plant growth, productivity, and post-harvest durability. Given the global pressures of population growth and food security concerns, environmentally benign strategies such as H₂ supplementation are gaining attention. The review discusses how both endogenous and exogenously applied H₂ influences plant cellular functions and stress tolerance mechanisms. While the precise molecular pathways through which H₂ acts in plant systems remain incompletely characterized, its safety profile and ease of application support its potential integration into future agricultural and horticultural practices.

### Mechanism

Exogenously supplied H₂, primarily via hydrogen-saturated water, modulates plant cellular functions to reduce damage from salinity, heavy metals, and drought stress; however, the precise intracellular molecular mechanisms remain to be fully elucidated.

## Bibliographic

- **Authors**: Zulfiqar F, Russell G, Hancock JT
- **Journal**: Planta
- **Year**: 2021 (2021-08-21)
- **PMID**: [34420086](https://pubmed.ncbi.nlm.nih.gov/34420086/)
- **DOI**: [10.1007/s00425-021-03706-0](https://doi.org/10.1007/s00425-021-03706-0)
- **Study type**: review
- **Delivery route**: hydrogen-rich water
- **Effect reported**: not assessed

## Delivery context

Hydrogen-rich water is a low-risk delivery route, but the achievable systemic hydrogen dose is bounded. For clinical applications, inhalation is the most efficient route; inhalation, however, carries explosion risk, and concentration matters (empirical LFL of 10% applies to inhalation environments; high-concentration devices are documented in the Consumer Affairs Agency accident database and are not recommended).

## Safety notes

Hydrogen-rich water is a low-risk delivery route, but the achievable systemic hydrogen dose is bounded. For clinical applications, inhalation is the most efficient route; inhalation, however, carries explosion risk, and concentration matters (empirical LFL of 10% applies to inhalation environments; 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 34420086. https://h2-papers.org/en/papers/34420086
> **Source**: PubMed PMID [34420086](https://pubmed.ncbi.nlm.nih.gov/34420086/)