School of Earth and Environmental Sciences, University of Portsmouth, Portsmouth, Hampshire PO1 3QL, UK.
Biol Lett. 2012 Aug 23;8(4):594-7. doi: 10.1098/rsbl.2012.0150. Epub 2012 Apr 11.
It has been hypothesized that radiation-induced oxidative stress is the mechanism for a wide range of negative impacts on biota living in radioactively contaminated areas around Chernobyl. The present study tests this hypothesis mechanistically, for the first time, by modelling the impacts of radiolysis products within the cell resulting from radiations (low linear energy transfer β and γ), and dose rates appropriate to current contamination types and densities in the Chernobyl exclusion zone and at Fukushima. At 417 µGy h(-1) (illustrative of the most contaminated areas at Chernobyl), generation of radiolysis products did not significantly impact cellular concentrations of reactive oxygen species, or cellular redox potential. This study does not support the hypothesis that direct oxidizing stress is a mechanism for damage to organisms exposed to chronic radiation at dose rates typical of contaminated environments.
据推测,放射性诱导的氧化应激是切尔诺贝利周围放射性污染地区内生物多样性受到广泛负面影响的机制。本研究首次通过模拟辐射(低线性能量转移β和γ)在细胞内产生的辐射分解产物以及与切尔诺贝利禁区和福岛当前污染类型和密度相适应的剂量率,从机制上检验了这一假设。在 417 µGy h(-1)(切尔诺贝利污染最严重地区的代表性剂量率)下,辐射分解产物的生成并没有显著影响细胞内活性氧物质的浓度或细胞氧化还原电位。本研究不支持这样的假设,即直接氧化应激是生物体在典型污染环境的剂量率下暴露于慢性辐射时受到损害的机制。