# Estimation of the hydrogen concentration in rat tissue using an airtight tube following the administration of hydrogen via various routes.
> 各種投与経路による水素投与後のラット組織内水素濃度の推定：気密チューブを用いた新規測定法


## Abstract

This study examined hydrogen concentration dynamics in Wistar rat blood and organ tissues following four distinct delivery routes: oral hydrogen super-rich water, intraperitoneal hydrogen super-rich saline, intravenous hydrogen super-rich saline, and inhaled hydrogen gas. A newly developed measurement approach combined high-sensitivity sensor gas chromatography with tissue homogenization performed inside airtight tubes, enabling stable and precise quantification. Peak hydrogen concentrations were observed at 5 minutes post-administration for oral and intraperitoneal routes, whereas intravenous delivery produced a peak at 1 minute. Inhalation resulted in a significant and sustained elevation beginning at 30 minutes. These findings establish a reliable analytical framework for characterizing hydrogen pharmacokinetics across tissues, which may inform the design of future experimental and clinical investigations involving molecular hydrogen.

### Mechanism

Hydrogen concentration kinetics in rat tissues vary by delivery route: intravenous administration produces the fastest peak at 1 minute, oral and intraperitoneal routes peak at 5 minutes, and inhalation yields a sustained elevation from 30 minutes onward, reflecting differences in absorption and distribution pathways.

## Bibliographic

- **Authors**: Liu C, Kurokawa R, Fujino M, Hirano S, Sato B, Li XM
- **Journal**: Sci Rep
- **Year**: 2014 (2014-06-30)
- **PMID**: [24975958](https://pubmed.ncbi.nlm.nih.gov/24975958/)
- **DOI**: [10.1038/srep05485](https://doi.org/10.1038/srep05485)
- **PMC**: [PMC4074787](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4074787/)
- **Study type**: animal study
- **Delivery route**: mixed routes
- **Effect reported**: not assessed

## 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 24975958. https://h2-papers.org/en/papers/24975958
> **Source**: PubMed PMID [24975958](https://pubmed.ncbi.nlm.nih.gov/24975958/)