Stress response signals can propagate between cells damaged by targeted effects (TE) of ionizing radiation (e.g. energy depositions and ionizations in the nucleus) and undamaged “bystander” cells, sometimes over long distances. Their consequences, called non-targeted effects (NTE), can substantially contribute to radiation-induced damage (e.g. cell death, genomic instability, carcinogenesis), particularly at low doses/dose rates (e.g. space exploration, some occupational and accidental exposures). In addition to controlled laboratory experiments, analysis of observational data on wild animal and plant populations from areas contaminated by radionuclides can enhance our understanding of radiation responses because such data span wide ranges of dose rates applied over many generations. Here we used a mechanistically-motivated mathematical model of TE and NTE to analyze published embryonic mortality data for plants (Arabidopsis thaliana) and rodents (Clethrionomys glareolus) from the Chernobyl nuclear power plant accident region. Although these species differed strongly in intrinsic radiosensitivities and post-accident radiation exposure magnitudes, model-based analysis suggested that NTE rather than TE dominated the responses of both organisms to protracted low-dose-rate irradiation. TE were predicted to become dominant only above the highest dose rates in the data. These results support the concept of NTE involvement in radiation-induced health risks from chronic radiation exposures.

应激反应信号可以在被电离辐射（例如细胞核中的能量沉积和电离）的靶向效应 (TE) 受损的细胞和未受损的“旁观者”细胞之间传播，有时传播距离很远。它们的后果，称为非靶向效应 (NTE)，可显着导致辐射诱导的损伤（例如细胞死亡、基因组不稳定、致癌），特别是在低剂量/剂量率下（例如太空探索、某些职业和意外照射）。除了受控的实验室实验外，对来自受放射性核素污染地区的野生动植物种群的观察数据进行分析可以增强我们对辐射响应的理解，因为这些数据涵盖了多代应用的广泛剂量率范围。拟南芥）和来自切尔诺贝利核电站事故区的啮齿动物（Clethrionomys glareolus）。尽管这些物种的内在放射敏感性和事故后辐射暴露量级差异很大，但基于模型的分析表明 NTE 而不是 TE 主导了两种生物对长期低剂量率辐射的反应。预计 TE 仅在数据中的最高剂量率以上才占主导地位。这些结果支持 NTE 参与慢性辐射暴露引起的辐射引起的健康风险的概念。