Rehabilitation


Draft document: Rehabilitation
Submitted by Mikhail Balonov, ICRP C2, Institute of Radiation Hygiene, St. Petersburg, Russia
Commenting as an individual

GENERAL COMMENTS This is very important, long-awaited ICRP document. It contains scientifically-based advice on provision of radiation safety and more in the areas with elevated radiation levels. Among those, the areas with radioactive residues from past activities or nuclear/radiological events (including accidents) are of primary importance. Concerning the scope of the document under consideration, is not the issue of Protection of Individuals Living in TERRITORIES WITH ELEVATED RADIATION LEVELS more general than the issue of Protection of Individuals Living in LONG TERM CONTAMINATED TERRITORIES AFTER A NUCLEAR ACCIDENT OR A RADIATION EMERGENCY? I mean in terms of Application of the Commission''s Recommendations. If so, the document scope could be widened. It would be helpful to define in this document widely used terms as ‘contaminated territory’, ‘contaminated foodstuffs’, etc. More generally, to consider applicability of the adjective ‘contaminated’ to the protection against environmental radiation. Generally, there is little reference in the draft document under consideration to the technical descriptions of remediation technologies, eg IAEA’s TRS-363, EC’s project STRATEGY, etc. I don’t mean technologies should be presented in detail but at least grouped as mentioned in para (57) and referred to. More guidance could be given on the establishing of reference levels and derived reference levels for typical existing situations and respective exposure pathways. The issue of mass health surveillance does not seem to be directly relevant to rehabilitation of areas with elevated radiation levels and, more generally, to radiological protection against long-term low-level radiation. Radiation monitoring is first activity to be applied in areas affected by radioactive fallout. The monitoring data will be inevitably converted in dose estimates that can be used in order to project possible health consequences. ‘Often, the majority of persons will have received very low doses and will not need subsequent medical care or follow-up [WHO 2006]’. However, if dose-based assessment defines a population group with substantially elevated risk of health effects and ‘medical monitoring’ of that group is justified with regard of early detection and treatment of cases, then health surveillance should be implemented. Still this does not seem to be a part of rehabilitation process. This point is all the more relevant to epidemiological studies of radiation-induced health effects. SPECIFIC COMMENTS Paragraphs (4), (5). In the reviewer’s view, the transition from an emergency exposure situation to a following existing exposure situation depends not only from the level of exposure but also from the pace of change of environmental radiation conditions. From the Russian Chernobyl experience, we considered emergency situation (intermediate phase) as long as radiation conditions (air dose rate, radionuclide concentrations in foodstuffs, etc) were substantially changing during weeks to months and switched to late/recovery stage (actually, existing exposure situation) when their changes slowed down to substantial changes during years and decades. Paragraphs (11), (55), (80), etc. The statement ‘In a post-accidental situation, the main exposure pathway will generally be the ingestion of foodstuffs’ is too general. That depends on radionuclide composition, environmental properties, etc. For instance, in some Chernobyl-affected areas with soils reach of clay (black soil, etc) the role of internal exposure is negligible (few per cents of total dose) because of strong fixation of 137Cs in soil and low transfer to biota. In many affected areas contribution of external and internal exposures to population dose is comparable to each other and only in areas with organic (peaty) soil the internal exposure really dominates. Concerning 5.1 Radiation monitoring, it would be useful to define in (69) the ultimate practical objective of radiation monitoring as comparison of obtained human exposure levels with reference levels as input in procedures of justification and optimization of remediation actions if any. More on that can be found in IAEA’s RS-G-1.8 on Environmental and Source Monitoring for Purposes of Radiation Protection that includes guidance on environmental monitoring in prolonged exposure situations and on practical interpretation of monitoring data. In para (82), for consistency, the reviewer would not recommend to set derived national reference levels (DRLs) of radionuclides in foodstuffs higher than recommended by CAC based on consideration of import conditions. In para (83) reference to international guidance on agricultural countermeasures IAEA’s TRS-363 would be helpful.


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