During the Fukushima accident protective actions taken to reduce radiation exposure resulted in death and other clearly observable severe health effects among the public. This occurred although the radiation exposure, even if no protective action had been taken, was too low to result in any detectable adverse radiation-induced health effects.
This pointed out the need for a way to compare risks of radiation-induced health effects versus the risks of protective action. The fundamental issue is justification, i.e. will a particular action taken to reduce exposure do more good than harm. Protective action decisions are ultimately made by the public and public officials. Therefore what is needed is a means for the public and public officials to compare the risk of observable radiation-induced effects versus the risks of observable impacts from protective actions. This document does not help to address this issue and may add to the confusion of the public and professional community concerning health risks of radiation exposure versus the health impact of protective actions. For example:
- The document supports the use of risk estimates (e.g. Table 5.2) based on LNT at doses well below those from which any radiation-induced health effects would be seen. The document talks about great uncertainties in these estimates without clearly stating that at low doses no adverse radiation induced health effects will be detectable. This makes it impossible for the public to compare the health effects from exposure with those from protective actions.
- The document states that LNT based reference levels could be a basis for making decisions during an emergency but it does not point out that the reference levels in ICRP 103 have not been shown to be justified. ICRP 103 points out that such justification is beyond the expertise of ICRP but this is not highlighted in ICRP 103 or this document. It’s possible that the use of these reference levels were the basis for protective actions that resulted in deaths and other severe health effects during Fukushima.
It should be made clear that neither this document nor the reference levels in ICRP 103 provide a basis for making decisions resulting in justified protective actions during an emergency.
See for a further discussion of this issue: March 2018 Health Phys, 114(5):511–526; 2018; Saving Lives and Preventing Injuries from Unjustified Protective Actions – Method for Developing a Comprehensive Public Protective Action Strategy for a Severe NPP Emergency; J. Callen and T. McKenna