Goodhead D T
Medical Research Council, Radiobiology Unit, Chilton, Didcot, United Kingdom.
Health Phys. 1988 Aug;55(2):231-40. doi: 10.1097/00004032-198808000-00015.
Studies of the spatial and temporal distribution of microscopic radiation doses lead to potentially important questions regarding conventional approaches to radiation protection. The short ranges of alpha-particle and Auger-electron emissions from radionuclides lead to uncertainties in assessing their hazards. The conventional extrapolations from intermediate doses to low doses and dose rates are questioned by observed dose-rate effects in the so-called "initial slope," by the total lack of data for single tracks in cells and by the possibility of multiple-cell effects. At all subcellular levels, even down to DNA, high linear-energy-transfer (LET) radiations can produce unique initial damage, different from that possible with low-LET radiations, and therefore may even, in principle, produce unique final biological effects. This questions simple extrapolations from low- to high-LET radiations and the application of universal quality factors to diverse effects. Further understanding of these questions could lead, in future, to substantial increases or decreases in estimations of risk.
对微观辐射剂量的空间和时间分布的研究引发了关于传统辐射防护方法的潜在重要问题。放射性核素发射的α粒子和俄歇电子射程较短，这导致在评估其危害时存在不确定性。从中间剂量到低剂量和剂量率的传统外推法受到了所谓“初始斜率”中观察到的剂量率效应、细胞中单轨迹数据的完全缺乏以及多细胞效应可能性的质疑。在所有亚细胞水平，甚至低至DNA层面，高传能线密度（LET）辐射都能产生独特的初始损伤，这与低LET辐射可能造成的损伤不同，因此原则上甚至可能产生独特的最终生物学效应。这对从低LET辐射到高LET辐射的简单外推以及将通用品质因数应用于各种效应提出了质疑。对这些问题的进一步理解未来可能会导致风险估计大幅增加或减少。
