# Radiation Effects of Normal B-Lymphoblastoid Cells after Exposing Them to Low-Dose-Rate Irradiation from Tritium β-rays

## TL;DR

This study investigates how low-dose tritium radiation affects mitochondria in B-lymphoblastoid cells, finding significant changes in ATP levels at 500 mGy.

## Contribution

The study reveals that tritium β-rays uniquely affect mitochondrial function at low doses, distinct from X-rays.

## Key findings

- Tritium β-rays at 500 mGy significantly reduced ATP levels compared to sham-irradiated cells.
- X-ray irradiation at the same dose did not show similar ATP level changes.
- Mitochondrial sensitivity to tritium β-rays suggests their importance in assessing tritium radiation risks.

## Abstract

Tritium is one of the most significant fuels in fusion reactors and it also represents an important radioactive isotope discharged into the environment from nuclear power plants. The risk of tritium should be answered before the construction of fusion reactors. Mitochondria have been identified as a potentially sensitive target for investigating low-dose/low-dose-rate radiation effects, with extensive experimental results obtained using X-ray irradiation. In this manuscript, we experimentally studied the impact of mitochondrial function regulation on tritium radiation biological effects. It was found that there was no significant difference in cell viability induced by different doses. However, the results of ATP levels showed a considerable difference after irradiation at a dose of 500 mGy by tritium β-rays compared to the sham-irradiated sample, while the levels obtained with X-ray irradiation were almost identical to the sham-irradiated sample. In contrast, ATP levels for both tritium β-rays and X-rays at a dose of 1.0 Gy showed little difference compared to the sham-irradiated sample. This suggests that mitochondria might be a potentially sensitive target for investigating tritium β-ray irradiation effects, and they are helpful for the risk evaluation of tritium for the development of fusion energy.

The effects of tritium at low doses and low dose rates have received increasing attention due to recent developments in fusion energy and the associated risks of tritium releases into the environment. Mitochondria have been identified as a potential candidate for studying the effects of low-dose/low-dose-rate radiation, with extensive experimental results obtained using X-ray irradiation. In this study, irradiation experiments were conducted on normal B-lymphoblastoid cells using HTO at varying doses. When compared to X-ray irradiation, no significant differences in cell viability induced by different doses were observed. However, the results of ATP levels showed a significant difference between the irradiated sample at a dose of 500 mGy by tritium beta-rays and the sham-irradiated sample, while the levels obtained with X-ray irradiation were almost identical to the sham-irradiated sample. In contrast, ATP levels for both tritium beta-rays and X-rays at a dose of 1.0 Gy showed minimal differences compared to the sham-irradiated sample. Furthermore, distinct effects at 500 mGy were also confirmed in both ROS levels and apoptosis results obtained through tritium beta-ray irradiation. This suggests that mitochondria might be a potential sensitive target for investigating the effects of tritium beta-ray irradiation.