In response to Dubrova (1), our intent is to provide a cogent argument for the experimental design in Wickliffe et al. (2) and address concerns expressed by Dubrova in his letter.
The central question is “What are the actual, biological consequences of exposure to doses and, more importantly, dose rates of ionizing radiation that cannot be investigated in a controlled laboratory experiment?” (3). This question forms the core of recent efforts to explore the ultra-low-dose component of the current radiation effects models that are used to predict risk. A major weakness of the application of these models to low-dose-rate radiation is the lack of empirical substantiation. Under laboratory conditions, actual continuous, chronic exposure to low-dose-rate radiation is difficult to administer. The only alternative is to find those habitats where this type of exposure exists (3 ,4). Our study...
