Dosimetric quantities

*** REVIEW COMMENTS FROM THE WORLD NUCLEAR ASSOCIATION *** 1 July 2005 Dr. Roger Clarke and Dr. Lars-Erik Holm International Commission on Radiological Protection SE-171 16 Stockholm Sweden Subject: ICRP Path Forward to the Next Recommendations WNA Views on the ICRP Proposed Profound Changes to the Current RP System and on Continuing to Build an International Consensus towards an Improved Proposal For several years, international policy on radiological protection has been under discussion with a view to a significant revision (recently delayed until 2006-2007). The focal point of this discussion has been an evolving draft proposal of the International Commission on Radiological Protection (ICRP). The ICRP’s seminal role in its field is well-known. Generally, ICRP recommendations are translated into the international and national standards that govern industry operations worldwide. The current ICRP draft proposal, which is entitled: “2005 Recommendations of the International Commission on Radiological Protection”, was presented in May 2004 at a key international conference called IRPA-11. This proposal emerged from two earlier forums jointly organized by ICRP and the Nuclear Energy Agency (NEA) of the Organization for Economic Co-operation and Development (OECD). Moreover, following IRPA-11, ICRP launched an open consultation on its draft proposal that ended in December 2004. This openness in the development of the next ICRP recommendations has been widely appreciated by the international RP community and no doubt helped many parties further reflect on the current RP system and on its potential evolution. Further to this open consultation process, ICRP acknowledged the overall negative reaction its draft proposal provoked. The key reasons that seem to explain this negative reaction are that: 1. The ICRP proposal includes a number of ‘Profound Changes’ to the current RP system 2. The general context does not warrant such changes 3. The overall rationale of the ICRP proposal is insufficient in view of such changes The most fundamental of these ‘Profound Changes’ (detailed herein in Annex A) are: 1. The introduction of maximum dose constraints that are given a primary, broader and stricter role than the current dose constraints (defined as part of the current optimization procedure) and even than the current dose limits. Figure 1 herein illustrates the potential magnitude of this issue for ‘Practices’. 2. An RP system to be based on natural background radiation rather than on the well-developed health risk-based approach of the current RP system. 3. A series of subsequent steps, beyond the introduction of a broad policy on the RP of non-human species, are prematurely introduced as an integral part of the RP system when the current common position of the international community (IAEA meeting in Vienna, June 2004) is to first develop an international consensus on the need for such a new component to the RP system, and then, if necessary, to develop and define its form and content. This effort is to be carried out through an IAEA plan of activities (yet to be approved by the Member States) that will coordinate, the input from many parties over the next few years, including that from IAEA, UNSCEAR, ICRP and many others. It would therefore seem more appropriate that ICRP puts forward its developmental work on non-human species for deliberation as part of this IAEA process before considering including it as an integral part of the RP system. Key factors that show that the general RP context does not warrant such ‘Profound Changes’ include: · There is widespread recognition of the need for stability in regulatory systems - many international and national regulations have only fairly recently been brought into line with the current RP system. · The current RP system is working well for ‘Practices’. · ICRP’s new scientific evidence that indicates that the overall risk from ionizing radiation is slightly lower than originally thought (ICRP60), is further confirmation of the adequacy of the current RP system. Our views are that the current RP system can and should be improved through consolidation and simplification with substantive changes being focused to correct specifically identified shortcomings or weaknesses. For a careful and smooth evolution of the current RP system, it is essential that any proposed changes do not unnecessarily disturb the current RP system for “Practices” (e.g. see Figure 1). The ICRP draft proposal should clearly identify shortcomings or weaknesses and explain how it specifically helps to address them. It is precisely this overall rationale that is currently insufficient. In March 2005, ICRP asserted that many comments on its draft proposal “arise because the Foundation Documents (FDs) have not yet been put out for consultation”. The resulting expectation was that ICRP’s five draft FDs would complement its draft proposal (including the overall rationale of the proposal). ICRP’s openness with regard to the consultation on these draft FDs is appreciated. Our review of these draft FDs confirms that they fall short especially in terms of an overall rationale for the proposed changes. In other words, the FDs do not seem to clearly identify the shortcomings or weaknesses of the current RP system or explain how the proposed changes specifically help to address them. We believe that before considering moving forward, this step is essential in order to fully understand and carefully assess any substantive changes to the current RP system. Concerning the ‘Profound Changes’ highlighted herein (Annex A), the FDs do not seem to bring explanations that would allow us to modify our position. WNA therefore feels it important to first draw the attention of the international RP community to the WNA views about the ICRP draft proposal in the context of continuing to build an international consensus towards an improved draft proposal. In the next pages, these views are presented in the following categories: I. Areas that seem to be in line with the current international consensus II. Areas that seem to have evolved but need to progress further III. Areas that seem to depart from the current international consensus To complement our broad comments on the draft proposal, we also offer herein (Appendix E) a few specific comments on each of the FDs. Given the current Profound Changes in the draft proposal, we have not attempted to provide a comprehensive list of specific comments on the FDs. We feel it more appropriate to offer such more comprehensive specific comments at a later stage once the overall rationale of the ICRP proposal has been expressed more clearly. We hope that this overall rationale will help better understand the ‘Profound Changes’ that ICRP is proposing to the current RP system. In view of the upcoming ICRP deliberations, we hope that this information could be useful to a wide range of interested parties for the preparation of their own submissions to ICRP. Sylvain Saint-Pierre Director for Environment and Radiological Protection * see our e-mail submission for the graphic on the info below * Current RP System(as applied by the nuclear industry) ICRP Proposed Profound Changesto the Current RP System “Dose Limit” (individual-related, for “Practices” only) – numerically set by ICRP for adoption into regulatory standards “Dose Limit” (individual-related, for “Planned or Normal Situations” only) – numerically set by ICRP for adoption into regulatory standards “Maximum Dose Constraints” (for “All Situations”) – numerically set by ICRP for adoption into regulatory standards “Maximum Dose Constraints” (for normal situations multiple sources) – numerically set by ICRP “Current Dose Constraint” (as an upper bound to the “Optimization” process) – numerically set by the local stakeholders. In some circumstances, this can translate into an “Authorized Level” “Dose Constraints” for Specific Situations (as an upper bound to the Optimization process) – numerically set by the local stakeholders. This seems to no longer can translate into an “Authorized Level” “Authorized Level” Note – Complementary information to Figure I is included in Annex D * text carries on * WNA Views on the ICRP Draft Proposal (and FDs) in the Context of Continuing to Build an International Consensus towards an Improved Draft Proposal I - Areas that seem to be in line with the current international consensus 1. “There is no hurry” – in terms of significant work that lies ahead for the development and completion of a suitable proposal for the next recommendations. 2. The overall intent to consolidate and simplify the current RP system with a view to making it easier to understand and comprehend. 3. The indications that the proposal “will consolidate and replace all the numerical advice included in and developed” since ICRP60 “(stand-alone document)”. II - Areas that seem to have evolved but need to progress further 1. The draft proposal shows progress in terms of the consolidation of information into a main stand-alone document. ICRP should consider further consolidating this information. Key suggestions for the main stand-alone document are: · Significantly expand (preferably at the beginning) the rationale that identifies the specific shortcomings or weaknesses of the current RP system and explain how the proposal specifically helps to address them, without unnecessarily disturbing the rest of the current RP system. · Significantly expand (preferably at the beginning) the core information about the ICRP itself (its mission, role, aim, scope, etc., including its relationships with other key international organisations) so that a non-familiar reader can have a broader view and understanding of ICRP and of its recommendations. This would be of great value to a broad range of stakeholders. · Group all policies together along with the key numerical values of protection (i.e. dose limits). Simply stating that some or all post-ICRP60 policies continue to be valid does not really address the current concern about consolidation, simplification and clarity and in fact appears to be in contradiction to this objective. A stand-alone document explaining which values hold would be better. · Simplify the number of key numerical values of protection. At the international level, numerical dose limits should be kept whereas numerical maximum dose constraints should not as the latter cannot possibly be integrated without raising important issues about the current RP system. (Though, the current concept of dose constraints should be kept.) Annex B herein further elaborates on this issue. · The supporting scientific information (such as the radiation weighting factors) could be integrated into separate more detailed documentation. This would facilitate updating this data without triggering a review of the main document. 2. It is well recognized that the RP system for 'Intervention' is causing some difficulties. Further ICRP guidance in this respect would be most welcome provided that it does not perturb the RP system for “Practices”. Some progress has been made but further guidance is needed. For example, guidance on the specific context for using higher values than the current dose limits for the public is needed. The role and content of dose constraints in the context of ‘Intervention’ are unclear and warrant further explanations. 3. Extremely low doses – ICRP should consider recommending more clearly, for sound policy making, a practical dose level (which would theoretically bear some tiny risks) from which protection should be systematically applied – and in turn prevent applying the RP system where it is unlikely to produce any substantive RP benefit. ICRP should consider incorporating this practical dose level in its guidance on estimating risk from ionising radiation and on the scope of application for “Collective Dose”. Such a practical dose level is key for the overall coherence of the current RP system and is currently notably missing. It would also serve to better introduce the concepts of “Exclusion” and “Exemption”. These latter concepts are welcome but ICRP should consider further alignment with the international consensus reached by the IAEA (2004) (Annex C). III - Areas that seem to depart from the current international consensus The ‘Profound Changes’ addressed earlier herein depart from the current international consensus: 1. The introduction of maximum dose constraints: see Figure 1 We suggest keeping the current concept of dose constraints intact without introducing the concept of maximum dose constraints – which unnecessarily introduce multi-layers of dose constraints. 2. The RP system is based on natural background radiation rather than on the well developed health risk-based approach of the current RP system We suggest keeping the current health-risk approach for the basis of the RP system while allowing natural background radiation to be used as a useful comparator and for practical context. 3. A series of subsequent steps, beyond a broad policy on the RP of non-human species, are prematurely introduced as an integral part of the RP system For the time being, we suggest keeping the on-going ICRP developmental work outside of the scope of the draft proposal and of the FDs and ensuring that it is an integral part of the IAEA joint international effort (AIEA plan of activities, June 2004, Vienna, yet to be approved by the Member States). Once it is internationally road-tested and understood, the ICRP model on Reference Animals and Plants (definition and dosimetry) together with the similar developmental work of other key organizations, may eventually prove to be a key component in the development and definition of an RP system for non-human species. Other subsequent steps (e.g., a common approach, assessment of effects, derived consideration levels, etc.) on the potential use of this model that are proposed by the ICRP are even more premature at this stage. For such steps, the consensus of the RP community is that any consideration should proceed with great deliberation at the IAEA level – before reaching the stage of an adequate assessment framework that complements current tools commonly used to demonstrate protection of the environment. 4. Other “Profound Changes” · Practices and Intervention We suggest that the concepts of “Practices” and “Intervention” should be re-integrated as per the current RP system. Further developing the guidance on the concept of “Intervention” would be an improvement. The role and content of dose constraints in the context of ‘Intervention’ are unclear and warrant further explanations. · Optimisation or ALARA We suggest that the “Optimisation” Principle or As Low As Reasonable Achievable (ALARA, taking into account social and economic factors) should be kept as per the current RP system. Removing the new concept of maximum dose constraints should help to achieve this. It should be borne in mind that both quantitative aspects and qualitative aspects (the latter include “safety culture” and “stakeholder involvement”) are integral parts of ALARA. This is already accounted for in the IAEA Basic Safety Standards (BSS). We therefore see no need to introduce a distinction between Optimisation and ALARA. Best Available Technology (BAT), not entailing excessive costs, should be part of Optimisation with considerations for health-driven standards. This would be more consistent with the “Optimisation” Principle or ALARA and with the fundamental aim of the draft proposal which includes “the balancing of risks and benefits”. We are concerned about the implication of the ICRP proposal that ALARA may be an endless downward process; e.g. continue optimising exposures until all parties involved are in agreement as a way to move forward, BAT without considerations for health risk, and 0.01 mSv/y as the minimum dose constraint which implies applying ALARA somehow blindly at even lower doses! This clearly shows that the concept of a practical dose level mentioned earlier (page 6 – item 3) is key for the overall coherence of the current RP system and is currently notably missing. ANNEX A ICRP Proposed ‘Profound Changes’ to the Current RP System The highlights of our comments on the ICRP proposed ‘Profound Changes’ to the current RP system are presented below. For further detail on these comments and on other aspects of the draft proposal, please refer to our earlier letter to ICRP dated December 23, 2004. 1. The introduction of maximum dose constraints – See Figures 1 By ‘Profound Changes’ to ‘Practices’, we mean moving from the current RP system (as applied by the nuclear industry) consisting of: - “Justification”, - “Optimization” - with “Dose Constraint” which can, in some circumstances, translate into an “Authorized Level” - “Limitation” (“Dose Limit”); to the proposed RP system for “Planned or Normal Situations” consisting of: - Dose limit, - Maximum Dose Constraints (for All Situations) that are given a primary, broader and stricter role than the Current Dose Constraints (defined as part of the current optimization procedure) and even than the Current Dose Limit, - Maximum Dose Constraints (for normal situations multiple sources) - Expanded “Optimization” - with Dose Constraints (for Specific Situations - as an upper bound to the Optimization process), - “Authorized Level”. How could an RP system that includes dose limit, maximum dose constraints (two layers), dose constraints for specific situations (defined as upper bound to the optimization procedure) and authorized levels work better in practice? What are the differences between dose limit, maximum dose constraints, dose constraints for specific situations, and authorized level? How would this be simpler and easier to understand and comprehend? How could an RP system that makes dose limit secondary to more stringent maximum dose constraints be consistent with one of the main outcomes of the ICRP/NEA forum in April 2003 (Lanzarote, Spain) namely to “keep dose limit”? This implied that dose limit should remain the most stringent level of protection and that the concept of current dose constraints should stay intact as part of the optimization. Concerning ‘Intervention’, the role and content of dose constraints are unclear and warrant further explanations. It would also be useful to further explain the relation between action levels and dose constraints in the context of ‘Intervention’. 2. The RP system is based on natural background radiation rather than on the well developed health risk-based approach of the current RP system We recognise that a reference to natural background (including radon!) and to its inherent variability is a useful comparator and gives practical context for appreciating the appropriateness of protection actions. We believe that it is important to retain this. However, assessment of dose limits must continue to be guided by the question of whether a significant health risk is posed. For example, linking the public dose limit to health risk evidence is extremely important even if this may involve accounting for some kind of a safety factor. Current ICRP discussions seem to indicate that some connection is to be drawn between the world average natural background, which becomes 1 mSv/y if the contribution from radon is excluded, and the allowable public dose limit. The fact that this “without radon” level is roughly the same as the current public dose limit of 1 mSv/y is purely coincidental and has no scientific significance regarding the question of the adequacy of the public dose limit. Moreover, it is important to keep the system flexible in view of potential future health risk evidence that may trigger changes to the key values of protection (e.g.. dose limits). Irrespective of background, lower values may become appropriate should the risk from radiation be higher and vice-versa. The health risk assessment approach is fit for both human and non-human species. The case for moving away from a risk-based RP system to a RP system based on natural background radiation is not compelling. 3. A series of subsequent steps, beyond a broad policy on the RP of non-human species, are prematurely introduced as an integral part of the RP system There is a wide agreement that the current RP system has in practice provided appropriate standards of environmental protection, but also wide acknowledgement that the system needs to be further developed for completeness in order to fill a conceptual gap (i.e., exposure of non-human species where human exposure is not the predominant concern) and to address some specific outstanding situations. The IAEA, ICRP and UNSCEAR all have an important leadership role in ensuring a clear direction for future work and the co-ordination of activities to develop and implement a sound international framework for environmental RP. In exercising this leadership, the three organisations should collaborate on a joint “road map”. This effort is to be carried out through an IAEA plan of activities ((June 2004, IAEA Technical Meeting, Vienna, yet to be approved by the Member States) that will coordinate, the input from many parties over the next few years, including that from IAEA, UNSCEAR, ICRP and many others. It would therefore seem more appropriate that ICRP puts forward its developmental work for deliberation as part of this IAEA process before considering including it as an integral part of the RP system. For the time being, we therefore suggest keeping the on-going ICRP developmental work outside of the scope of the draft proposal and of the FDs and ensuring that it is an integral part of the IAEA joint international effort. Once it is internationally road-tested and understood, the ICRP model on Reference Animals and Plants (definition and dosimetry) together with the similar developmental work of other key organizations, may eventually prove to be a key component in the development and definition of an RP system for non-human species. Other subsequent steps (e.g., a common approach, assessment of effects, derived consideration levels, etc.) on the potential use of this model that are proposed by the ICRP are even more premature at this stage. For such steps, the consensus of the RP community is that any consideration should proceed with great deliberation at the IAEA level – before reaching the stage of an adequate assessment framework that complements current tools commonly used to demonstrate protection of the environment. For a more complete WNA position on the radiological protection of the environment/non-human species, please refer to our earlier letter to IAEA, UNSCEAR and ICRP dated February 2, 2003. 4. Other ‘Profound Changes’ “Practices” and “Intervention” · The key concepts of “Practices” and “Intervention” are replaced by the new concepts (not yet defined) of “normal operations” or “planned activities”, “accident or emergency situations”, and “controllable existing situations”; thus eliminating the important distinction between “Practices” and “Intervention”. It should be borne in mind that the well advanced international consensus on the “Principles of Nuclear, Radiation, Radioactive Waste and Transport Safety – DS298 – Safety Fundamentals” at the IAEA level, embraces the key concepts of “Practices” and “Intervention”. Optimization · By definition, maximum dose constraints are substantially different from the current dose constraints. This would imply corresponding changes to “Optimization”. · Indicating that Best Available Technology (BAT) and “Optimization” complement each other, can possibly substantially modify the essence of the “Optimization” Principle. BAT not entailing excessive costs, should be part of Optimization with considerations for health-driven standards. This would be more consistent with the “Optimization” and with the fundamental aim of the proposal which includes: “the balancing of risks and benefits”. ANNEX B The Key Issue of Simplifying the Number of Numerical Values of Protection Whereas there is a strong international consensus for integrating the current dose limits in a consolidated main document, numerical maximum dose constraints which would be more stringent than the current dose limits cannot be possibly integrated without disturbing the current RP system. Other key fundamental scientific values (such as the radiation weighting factors) can be integrated in separate ICRP documentation. We recognize that industry and many others may not have reacted when such more stringent numerical dose constraints were published, but it should also be recognized that the ICRP process for dealing with these values has not been subject to the same level of openness and international discussions/debates that ICRP60 and the current ICRP draft proposal were subject to. Anyhow, the fact remains that the proposed basis for these values appears weak and that these values have still not benefited from a real debate. Should this be relevant, applying the new ICRP MUM (Meet Understand and Modify) approach would be most welcome here. With this in mind, prudence and concern with regard to continuing to build a solid international consensus suggest that the case for having numerical maximum dose constraints in parallel to the current dose limits, thus interfering with the optimization process (accounting for social and economic factors), stakeholder involvement, and ultimately compliance matters, is not compelling. One cannot preclude that it may not be possible to define such values at the international level. ANNEX C Practical Dose Level for Making Sound Policy Making at Low Doses, Collective Doses, and Exclusion, Exemption and Clearance Levels Practical dose level for sound policy making at low doses – Defining a dose level from which protection should be systematically applied – and in turn preventing the application of the RP system where it is unlikely to produce any substantive benefit - is a necessity for sound policy making. Based on Optimization and its essential aim of achieving a reasonable balance of risks and benefits, it is clear that down to very low and extremely low doses, such a practical dose level has an important role to play even if it would bear some tiny theoretical risks. ICRP should consider incorporating this practical dose level in its guidance on estimating risk from ionizing radiation and on the scope of application for “Collective Dose”. We recognize that the context of the ICRP CI Task Group draft report may not be the suitable place to address this. However, the matter of adopting such a dose level on the basis of a reasonable balance between scientific and non-scientific issues should be seriously considered by the ICRP (at the upper level – e.g. Committee 4 or the Main Commission itself). Collective doses – We welcome the ICRP effort in limiting the scope of collective dose. As such, we recognize the value of disaggregating the collective dose results, provided that this procedure also includes a dose level as mentioned above. Exclusion and exemption levels – Similarly, we would welcome the concept of concentration levels from which protection should be systematically ensured. As part of optimization, provisions for higher concentration levels in the context of exemption and clearance levels would represent an improvement. This is another practical area where balancing beneficial actions giving rise to radiation exposure and the detriments of radiation exposure are particularly important. Further guidance would be welcome here. We would also welcome further alignment with the international consensus reached by the IAEA in 2004 on the key topic of exclusion, exemption and clearance levels. * see our e-mail submission for the graphic on the info below * ANNEX D Figure 2 - RP System for 'Practices' Key Features of the Current RP System:· “Justification”, “Optimization” and “Limitation”o Well implemented into the regulatory context· “Dose Constraint” as the upper bound of the “Optimization” processo Well implemented into the regulatory contexto “Dose Constraint” is numerically set by the local stakeholderso “Dose Constraint” for “Practices” can, in some circumstances, be translated into an “Authorized Level”· Context of Application for “Practices”o Well implemented into the regulatory context Key Features of the Proposed RP System:· “Dose Limit”, “Maximum Dose Constraints” and “Expanded Optimization”o “Maximum Dose Constraints” (for all situations and for normal situations multiple sources) can interfere with “Dose Limit” and “Optimization”, thus it can in turn interfere with compliance matters and the “Current Dose Constraint” set by the local stakeholderso How “Dose Limit” and “Maximum Dose Constraints” can co-exist?· “Dose Constraints for Specific Situations and “Authorized Level”o Do the “Current Dose Constraints” remain unchanged – e.g. as the upper bound of the optimization process? What is meant by “Authorized level”?· Context of Application for “Planned or Normal Situations”o Do the fundamental concepts of “Practices” and “Intervention” (and their differences) remain unchanged?o Do “Planned or Normal Situations” are the same than “Practices” Note: “Optimization” inherently accounts for social and economic factors. * Text carries on * ANNEX E A Few Specific Comments on the ICRP Foundation Documents (These comments complement those already mentioned earlier herein) 1. The Optimization of Radiological Protection – Broadening the Process · We are unsure about what is meant by “Broadening the Process”. If we have understood correctly, the report seems mainly to be about concepts of stakeholder involvement and of the quality of dialogue in the context of optimization. · The document gives the impression that optimization or ALARA is currently at the stage of cost-benefit (technical) analysis rather than at the stakeholder involvement and dialogue stage, and in turn, promotes an apparent shift towards the latter. It also puts a disproportionate emphasis on subjective matters as if there were no rationale other than the dialogue itself (and its various elements such as opinions, consensus, etc.). This view seems overly simplistic and far from the practical realities where stakeholder involvement and dialogue is already well implemented as part of ALARA (safety culture component). In doing so, it also tends to give the overall impression that stakeholder involvement and dialogue is much more complex than what is actually being done in practice. We also note the absence of any sense of hierarchy - which is normally expected in any responsible stakeholder process. We wonder what is the intended aim and objective of such a report in terms of practical guidance? · Radiological protection can be viewed as consisting of three key components: 1 - Design (e.g. defense in depth, etc.), 2 - Management System (policies, work procedure, monitoring, etc.),and 3 - People. Safety culture relates to the latter item. For a Foundation Document on optimization or ALARA, it is striking to note that the first two essential components of radiological protection (Design and Management System) have been clearly overlooked. Without these two key components, the current principle of optimization or ALARA would be largely degraded. These two essential components (Design and Management System) of radiological protection should be fully re-integrated and well developed into this document on optimization or ALARA. · Adding a definition of optimization and dose constraint would be helpful. Concerning dose constraint, we agree that: - It is set by the local stakeholders as an upper bound of the optimization process, - It does not relate to regulatory matters unless otherwise specified by the local stakeholders. For example, in some circumstances, a dose constraint can translate into an authorized level. We are not sure we understand the ICRP rationale for stating that: “Quantified values of constraints are recommended by the Commission, which apply to all situations. They help in deciding which value to choose in a specific situation.” It should be borne in mind that any numerical dose constraint set, at the international level, by ICRP at a lower value than the current dose limits, would interfere with the optimization process (accounting for social and economic factors), stakeholder involvement and dialogue, and ultimately with compliance matters. We would question the coherence of such numerical values. · Figure 1 is unclear and requires further explanations. · This document does not seem to address ‘Intervention’, and in particular the role and content of dose constraints and its relation to action level. · Given the ‘Profound Changes’ mentioned earlier, the disproportionate emphasis put on stakeholder involvement and dialogue, and the other issues just mentioned, we would like to better understand what is meant by: “The description of optimization is an evolution and consolidation, but not a fundamental change.” 2. Assessing Dose of the Representative Individual for the Purpose of Radiation Protection of the Public” · The overall direction in this document seems appropriate: definition of the representative individual, use of existing conditions as a starter to assess doses; and use of a sensitivity analysis as a complement. 3. “Biological and Epidemiological Information on Health Risks Attributable to Ionizing Radiation: A Summary of Judgements for the Purpose of Radiological Protection of Humans” · Please refer to our earlier letter to ICRP dated March 24, 2005 (ICRP C1 TG Report). 4. “Basis for Dosimetry Quantities Used in Radiological Protection” · Equivalent dose would now be called ‘radiation weighted dose’. This change does not seem compelling. Also, it might be more appropriate that these kinds of changes be led by organizations that are specialized in measuring units such as ICRU. · More emphasis would be put on Annual Limit of Intakes (ALI) and on Derived Air Concentrations. This change is welcome. · For ‘remainder’ tissues, w(T) is divided equally between the 15 specified tissues leading to additivity in effective dose. This change is welcome. · In equation 5.1 on page 34, the activity reduces with time and it is conventional to express dN/dt as negative · Non-stochastic effects (ICRP26) were renamed deterministic effects in ICRP60. They would now be called tissue reactions. This repeated changing of names causes confusion. The same comment applies to the change of equivalent dose to ‘radiation weighted dose’. These changes do not seem compelling. 5. “The Concept and Use of Reference Animals and Plants for the Purposes of Environmental Protection” · As with the draft proposal, this document prematurely advocates, in various ways, that the need for integrating a non-human component to the current RP system already exists. We believe that it is precisely these kinds of important issue that remain to be put forward and deliberated with the international RP community as part of the IAEA plan of activities on the radiation protection of the environment. · Concerning the various links to regulatory matters, the document is unclear and warrants further explanation. For example, paragraph 6 gives the impression that regulatory requirements that are directly aimed at the protection of wildlife and natural habitats already exit whereas paragraph 27 gives the impression that they are anticipated. It is also not clear if this refers to the international regulatory context or to another regulatory context. Although broad requirements for the protection of wildlife and natural habitats and for the protection of endangered species do exist at the international level, their translation to the very specific domain of the effects of ionization radiation on animals and plants would seem exaggerated and perhaps even inappropriate if considered in isolation of the many other factors (environmental releases from all industries, including the impact of climate change, agriculture, urban development, etc.) that impact on the overall well-being of animals and plants. One cannot exclude, a priori, the possibility that the impact of low doses of ionizing radiation may not even play a part in the prevailing factors. · We welcome the introduction of a policy that revolves around the radiological protection of animals and plants at the population level (or a higher organizational level). In this respect, paragraphs 246 and 247 of the draft proposal are key. We welcome the early development of a framework for assessing radiation effects in non-human species – with the expectation that such a system would primarily aim at establishing the links (robust scientific foundations) between effects at the individual level and the corresponding effects at the species level in terms of frequency of effects that are relevant to this latter level. However, as this early development is less about the policy itself than about how to implement the policy, we are not convinced that the ICRP proposal or a Foundation Document is a suitable place to address this matter at this time. Alternatively, putting this ICRP developmental work forward as an input for deliberation at the IAEA plan of activities would be welcome. We emphasize that the need/case for ICRP to focus at the individual level appears weak, and we therefore seek further clarification and explanation. Most current regulatory regimes aim directly or indirectly at the protection of animals and plants at the species level. Even efforts to protect individual rare or endangered animals and plants are aimed at protecting the remaining population of a species. We ask this: How, on a practical level, could the current widespread legal and regulatory structure possibly be adapted to a new protection policy and assessment framework not designed for the protection of species or populations? The technical difficulties and challenges for the development of the assessment framework (e.g. linking dose-response at the individual level and population effects level) should not be the driver of the ICRP policy on non-human species. Para. 247 of the draft proposal is key in this respect. · Concerning subsequent steps (e.g. a framework, a common approach/system, new standards, any related control matters, derived consideration levels etc.) that go clearly beyond the introduction of a policy, we firmly believe that this is premature and should not be included in the ICRP proposal or in a Foundation Document. It would raise confusion and be misleading. We believe that it is also the kind of important issue that remain to be put forward and deliberated with the international RP community as part of the IAEA plan of activities on the radiation protection of the environment. · The adequacy of the derived consideration levels approach remains to be demonstrated. We believe that a health risk assessment-based approach with guidance values of protection would be better and more consistent with the current approach used for humans (see also Annex A – item 2). One cannot exclude, a priori, that the derived consideration levels, which are based on a simple reference to natural background radiation, could translate into poor indicators of the real potential harm to the health of non-human species. · Please refer to our earlier letters to ICRP dated December 23, 2004 and to IAEA, UNSCEAR and ICRP dated February 2, 2003. The latter offers a more complete WNA position on the radiological protection of the environment/non-human species. *** EARLIER COMMENTS FROM THE WORLD NUCLEAR ASSOCIATION SENT TO ICRP (Dec 23, 2004) *** 23 December 2004 Dr. Roger Clarke and Dr. Lars-Erik Holm International Commission on Radiological Protection SE-171 16 Stockholm Sweden Re : WNA’s RPWG key review comments on the current ICRP proposal Dear Dr. Clarke and Dr. Holm The World Nuclear Association (WNA) is pleased to provide its key review comments on the ICRP’s current proposal for the evolution of the system of radiological protection. These review comments were prepared by the WNA’s Working Group on Radiological Protection (RPWG). The RPWG is composed of well-versed RP professionals who represent a wide-range of nuclear industry sectors in various countries and who have been constructively involved in the ongoing international debate on this key topic. Our broader WNA membership, which consists of more than 120 nuclear industry-related enterprises in more than 30 countries, was given an opportunity to contribute to these review comments. Our prime concern still revolves around the fundamental issue of dose constraints. At an earlier stage – in the context of the ICRP/NEA forum in April 2003 and again during the IRPA-11 conference in May 2004 – we raised the concern that acting at the international level to set numerical dose constraints at lower values than the dose limits would be inappropriate and would create important issues. Herein we explain our view again. A key example is our detailed discussion in attachment #2 of the 0.1 and 0.3 mSv/y post-ICRP60 dose constraints. Since that earlier stage, our closer examination of the current ICRP proposal has revealed that the issue of dose constraints has even more sweeping implications than we originally thought. Indeed, the current ICRP proposal would give a fundamentally different and broader role to dose constraints than in the current system – as described in ICRP60. We believe that the proposed re-definition of dose constraints, which would “quantify the most fundamental level of protection for workers and the public from single sources in all situations”, would disturb the key foundations of the current system of protection. Those foundations include dose limits, optimisation (or ALARA), current dose constraints that are set as part of the optimisation procedure, stakeholder involvement as an important input in the optimisation process, and the important distinction between ‘practice’ and ‘intervention’. The ICRP proposal would broaden the scope of dose constraints to single sources in “all situations”; i.e., normal situations, accidents and emergencies, and controllable existing exposure – thus covering ‘practice’ plus ‘intervention’. This would have the practical effect of making dose constraints more restrictive than the current dose limits. We therefore find it striking to note an insufficient discussion about the rationale for this change and its potentially far-reaching implications. We also note that the term “normal operations” is not defined. We are not convinced that this would be straightforward or that it would really contribute to clarifying the application of the RP system for practices. The proposed changes to dose constraints, with their wide implications for the RP system, seem inconsistent with key points that the ICRP itself affirms: o ICRP recognises the need for stability in regulatory systems at a time when “there is no major problem identified with the practical use of the present system of protection in normal situations” o ICRP recognizes that the current system is working well and there are no indications that its ability to continue to deliver well into the future has been compromised o Many international and national regulations “have only fairly recently implemented the 1990 Recommendations” o New scientific data point in the direction that the overall risk from ionising radiation is slightly lower than originally thought in ICRP60 The proposed changes are also inconsistent relative to one main outcome of the ICRP/NEA forum in April 2003: i.e., the international consensus to keep dose limits unchanged; this created the obvious expectation that dose limits would be kept as a fundamental level of protection (with justification and optimisation). To us, this indicates that dose limits have not been satisfactorily integrated into the current ICRP proposal. For such profound changes to the foundations of the RP system, we see it as essential that the key stakeholders (regulators, the nuclear industry, and others) clearly understand and comprehend the need and the case for the proposed changes. The current proposal violates this principle. We emphasise that a wide range of key stakeholders seems to share our view about the proposed changes to the current RP system (justification, optimisation, dose limits, practices and intervention) and about the insufficient rationale for the need/case for such changes. Most of the key presentations at IRPA-11 made this point in various ways. We also have a concern about the sequencing of the ongoing open consultation process. Because we know that several key building blocks of the RP system are upcoming in 2005 (for example, ICRP guidance on optimisation and on critical groups), we find it premature to regard our comments as “final” at this stage. Consequently, we seek further ICRP explanation as to how this future information will be integrated into the consultative process. While concerned about the current ICRP proposal, we do recognise topics on which there might be a need/case for improvement or evolution. Our reading of the ICRP proposal suggests three main topics: 1) Clarifying ‘intervention’ or the RP system for accidents, emergencies, and controllable existing exposure 2) Simplifying the post-ICRP60 dose constraints 3) Introducing a policy on non-human species. On these topics, we would welcome clearer explanations, at the beginning of the ICRP proposal, about the related shortcomings of the current RP system and about how the current proposal helps to address these specific topics without unnecessarily disturbing the RP system for practices. While expressing our concerns about the current ICRP proposal, we wish to underscore our belief in the value of the constructive ICRP-RPWG dialogue in which we have participated over the last two years. In that spirit, we are pleased to offer our suggestions (in attachment #1) on the following key issues: o Current RP system for practices o Intervention o Dose constraints: public exposure and occupational exposure o Optimisation or ALARA o Natural background o Policy on non-human species o Exclusion, exemption and clearance o Collective dose or dose matrix o Critical groups As our dialogue continues, we wish to stress the importance of achieving a clear process for addressing the proposed key changes to the current RP system. We welcomed the ICRP series of recent international events on its evolving proposals. We also welcome the ICRP’s open public consultation process. We encourage the ICRP to formalise this process still further as consultations progress. As a broad principle, we trust that the ICRP will bring forward, discuss and debate fully and transparently any major changes to the current RP system. Should the ICRP decide to move forward on with its proposal to make profound changes to the foundations (justification, optimisation and dose limits, practices and intervention) of the current RP system, we would attach particular importance to the question of clear process. One necessity would be a realistic timetable for adequately debating these changes in a few upcoming international events (e.g., IRPA-style). We welcome the ICRP effort to seek the views of competent RP representatives of all interested parties as the ICRP examines and seeks to improve the foundations of the current RP system. We also recognize that improved public understanding of radiation and related issues requires that the ICRP take into account the values and concerns of stakeholders outside the RP community. Respected ICRP leadership is indispensable for public trust and sustainable development. We appreciate this opportunity to contribute to the ICRP’s open consultation process, and we look forward to working further with you in exploring ways to improve the current RP system. Yours sincerely, Sylvain Saint-Pierre Director for Environment and Radiological Protection ATTACHMENT #1 Summary Views about a Potential Way Forward on Key Issues 1) The current RP system for “practices” should be kept unchanged – Justification, optimisation (and dose constraints as part of the optimisation procedure) and dose limits of the current RP system should be kept intact. 2) Intervention should be kept separated from “practices” – The scope of “intervention” is complex and has been often poorly understood. Any ICRP attempts to integrate the “world” of intervention into the more simple framework on practices would unduly disturb the RP system for “practices”. We encourage the ICRP to seek new options for addressing intervention without disturbing the RP system for “practices”. 3) Dose constraints: public exposure and occupational exposure – Provided that “intervention” is excluded from the domain of application, for public exposure, the introduction of the principle of source-related dose constraints for single sources, as a complement to the current public dose limit of 1 mSv/y, seems appropriate in the context of “practices”. However, at the international level, setting numerical values for dose constraints that would parallel the public dose limit would be inappropriate. Setting such numerical values is a matter that is best left to local stakeholders as part of their practical involvement in the optimisation process and ultimately as a means of ensuring compliance with the dose limit. Should ICRP have a role in setting numerical values for optimisation and for ensuring compliance? For occupational exposure, we believe that the principal control regime is the individual dose limit and ALARA, with source-related dose constraints having, as a principle, a secondary role at the international level in this case. Source-related dose constraints are in the context of occupational exposure more a matter for RP management at the workforce level. For simplification and greater clarity, ICRP should present the rationale for each post-ICRP60 dose constraint and foster a debate within the international RP community. In our view, greatly reducing (if not eliminating) the 30 or so post-ICRP60 dose constraints and expressing this clearly in the ICRP proposal would help achieve more simplicity and clarity. Rolling-in such dose constraints directly or indirectly by simple references to post-ICRP60 documents in the ICRP proposal is not appropriate. Any credible dose constraint value (maximum or otherwise) that is set internationally and that is practically equivalent to introducing new more stringent standards (lower values) than the dose limits should be well substantiated; its context of application should be well defined and explained; and it should be subject to open and transparent international debate with the competent and qualified representatives of concerned parties. Basis – We seek further information and explanation about the different drivers for introducing, at the international level, any of these quantified values in the system of radiological protection. What are the supporting international studies? What evidence exists on public health grounds and in practical cases that are universally applicable worldwide? Context of application – Any quantified dose constraints should be accompanied by a clear definition of the sources to which they are applied as well as clear explanations as to how this should be practically achieved. The proposed definition in the ICRP proposal helps little in this respect. Knowing the source is fundamental to any values on dose constraints and almost certainly not straightforward at the level of ICRP – even for a single source. This specific information is more the domain of the local stakeholders. Conversely, once this exercise has been well executed locally, a specific numerical dose constraint is not relevant at the international level. Defining numerical dose constraint values at the ICRP level appears paradoxical as it goes in the precise direction (e.g., responsibility of operating management, subject to the requirements of the competent national authorities) that the ICRP guidance understandably seeks to avoid (see e.g., para. 139, 162, 174 and 190). It can be argued that a “source” that would fit the definition of “the cause of an exposure” (para. 16) could include the behaviour of the individual himself, thus getting closer to the notion of doses. This unclear distinction between the source and the person exposed to that source would introduce another level of confusion. Conceptually, it can also be argued that accounting for all the individuals exposed to a given source (para. 130) bears similar limitations to accounting for all the sources contributing to the exposure of an individual (dose limit). The case for putting more emphasis on dose constraints than on dose limits is therefore not straightforward, especially considering that dose limits and that dose constraints as part of an optimisation process have delivered steady progress in radiological protection for over several decades. Optimisation and stakeholder involvement – We seek further explanation as to how the introduction of these quantified values at the ICRP level would fit with the aim of making the system simpler and easier to understand by stakeholders as part of the optimisation process. We would argue that introducing, at the international level, numerical dose constraints at values that are below the values of the dose limits is not coherent with the optimisation process and inconsistent with the ICRP’s emphasis on the importance of stakeholders input as part of this process (S11). 4) Optimisation or ALARA – Both quantitative aspects and qualitative aspects (the latter including “safety culture” and “stakeholder involvement”) are integral parts of ALARA. This is already accounted for in the IAEA’s Basic Safety Standards (BSS). We therefore see no need to introduce a distinction here. We are concerned about the implication of the ICRP proposal that ALARA may be an endless downward process; e.g., continue optimising until all parties are in agreement as a way forward, best available technology (BAT) without considerations for health risk, and 0.01 mSv/y as the minimum dose constraint which implies that ALARA at lower doses. This suggests that, one of the fundamental aims of the recommendations (para. S2) – beneficial actions giving rise to radiation exposure, and balancing them relative to the detriments of radiation exposure – has been lost or underplayed in the ICRP proposal discussions about optimisation. We advocate that this be fully reinstated in the ICRP proposal with suitable explanatory text (para. S2 is not enough). The lack of practical guidance about balancing beneficial actions giving rise to radiation exposure and the detriments of radiation exposure is a key shortcoming of the ICRP proposal. Protection against radiation exposure is essential but accounting for the beneficial actions is also important. Further guidance in this respect is necessary, especially when addressing optimisation. 5) Natural background – Background is background, with radon. It should continue to provide a useful perspective but the key values of the “RP system” should continue to be based on the current, well developed, and more defensible health-risk approach. It is well known and widely accepted that natural background averages about 2.4 mSv/y on a worldwide scale, and usually ranges from about 1 to 10 mSv/y depending on the geographical location, with many local exceptions that go up to 100 mSv/y. This important perspective is factored in around the world, and is part of the comprehensive public consultation process that led to the acceptance of “practices” and their licensing. We are puzzled by the proposal to exclude radon from natural background and the related provisions (e.g. para. 31). Para. 157 leaves the impression that radon is controllable everywhere and that it is only a matter of indoor environment. This view is inappropriate. Radon is also a matter of outdoor environment for which the level of control is much more limited; nor is it straightforward to control in an indoor environment. Should the need/case for a common system of protection for humans and non-human species ultimately become relevant, it is very unlikely that radon in habitat of animals and plants will be offered the same level of control as in homes and workplaces. If the contribution from radon is excluded, the world average natural background becomes 1 mSv/y. Current ICRP discussions seem to indicate that some connection is to be drawn between this level and the allowable public dose. But the fact that this “without radon” level is roughly the same as the current public dose limit of 1 mSv/y is purely coincidental and has no scientific significance regarding the question of the adequacy of the public dose limit. Assessment of the public dose limit must continue to be guided by the question of whether it poses a significant health risk. This principle also applies to non-human species should the need/case for a common system of radiological protection ultimately become relevant. It is important to keep the system flexible in view of potential future health risk evidence that may trigger changes to the key values of protection (e.g., dose limits for humans and dose-rate guidance values for non-human species). Irrespective of background, lower values may become appropriate should the risk from radiation be higher and vice-versa. The health risk assessment approach is fit for both human and non-human species. Associating “exposure levels” and the “need for action” is difficult to understand and comprehend, especially for levels within the range of natural background and for levels well below the current dose limit for the public. We also question the need for action for doses that are less than about 0.01 mSv/y. These messages would contribute to augmenting public fear about any man-made sources of radiation. They also appear inconsistent in view of para. 31, which states that “it is incremental risk (not in isolation of natural background) that is of interest for decision-makers”. Associating “exposure levels” and the “need for action” is not sound. 6) Policy on non-human species – We welcome the introduction of a policy that revolves around the radiological protection of animals and plants at the population level (or an higher organisation level). In this respect, paragraphs 246 and 247 are key. We welcome the early development of a framework for assessing radiation effects in non-human species – with the expectation that such a system would primarily aim at establishing the links (robust scientific foundations) between effects at the individual level and the corresponding effects at the species level in terms of frequency of effects that are relevant to this latter level. However, as this early development is less about the policy itself than about the how to implement the policy, we are not convinced that the ICRP proposal is the suitable place to address this matter at this time. Concerning subsequent steps (e.g., a framework, a common approach/system, new standards, and any related control matters) that go clearly beyond the introduction of a policy, we firmly believe that this is premature and should not be included in the ICRP proposal. It would raise confusion and be misleading. We stress that one key outcome of the June 2004 IAEA meeting on a draft international action plan for the development of such an assessment framework is the international consensus that the need/case for any subsequent steps has not yet been made. We emphasise that the need/case for ICRP to focus on the individual level appears weak, and we therefore seek further clarification and explanation. Most current regulatory regimes aim directly or indirectly at the protection of animals and plants at the species level. (Even efforts to protect individual rare or endangered animals and plants are aimed at protecting the remaining population of a species.) We ask this: How, on a practical level, could the current widespread legal and regulatory structure possibly be adapted to a new protection policy and assessment framework not designed for the protection of species or populations? The technical difficulties and challenges for the development of the assessment framework (e.g., linking dose-response at the individual level and population effects level) should not be the driver of the ICRP policy on non-human species. Para. 247 is key in this respect. 7) Exclusion, exemption and clearance – We welcome the ICRP approach that leads to concentrations below which current practices would no longer be subject to the requirements of the RP system. As part of optimisation, provisions for higher concentrations in the context of exemption and clearance levels would represent an important improvement. This is another practical area where balancing beneficial actions giving rise to radiation exposure and the detriments of radiation exposure are particularly important. Further guidance would be welcome here. We would also welcome further consistency between ICRP and the IAEA in the field of exclusion, exemption and clearance. 8) Collective dose or dose matrix – We welcome the statements in para. 198 and 200 that limit the scope of collective dose. We recognise the value of disaggregating the collective dose results, provided that this procedure also includes a lower bound cut-off dose level – by analogy with the concept of exclusion, exemption and clearance. 9) Critical groups – It is striking to note the changes in the definition of some factors that are considered for critical groups. Para. 172 states that “the critical group may, however, include some individuals with extreme or unusual habits and should be selected such that all relevant habits are taken into account”. This change is inadequate and would represent a major shift in comparison to the current policy. 10) Terminology – The need/case for replacing the following terms does not seem compelling: o the term ‘deterministic effects’ by the term ‘tissue reactions’ o the term ‘ stochastic effects’ by the term ‘cancer and heritable disease’. ATTACHMENT #2 The post-ICRP60 dose constrains of 0.1 and 0.3 mSv/y: A key practical example that provides perspective on our comments Let us examine more closely the practical case of the proposed maximum dose constraint of 0.3 mSv/y that ICRP is proposing for normal situations with multiple dominant sources (para. 164) and of the related and even more stringent maximum dose constraint of 0.1 mSv/y. The latter seems indirectly included by reference (S29) to ICRP77, 81 and 82. All of these values are related to the disposal of radioactive waste. Basis – We emphasise that a simple reference to ICRP77, 81 and 82 does not do the job. When examining ICRP77 (para. 48), which introduces the value of 0.3 mSv/y, we note the apparent absence of international studies that would support such a value and of related analyses and discussions. As a basis, ICRP77 appears to refer only to a “review of the doses to critical groups in England and Wales (Robinson et al., 1994)”. Without further evidence on public health grounds and further analysis of practical cases that would be universally applicable across the world, we question the relevance of bringing such values into the international system of radiological protection. ICRP81 and 82 go further in that direction without apparent further international basis. Among other things, ICRP82 (para. ‘k’ and 132) introduces the value of 0.1 mSv/y for the prolonged component of the exposure. The apparent shortcomings in international basis for this value seem similar to those for the value of 0.3 mSv/y. Among other issues, there is a real concern that lower dose constraints (1 mSv/y) for effluent discharges may later set an unrealistic expectation that can bear huge implications for the transport of spent nuclear fuel (SNF) and high level waste (HLW) and for their disposal in deep geological repositories. Continuing to set dose constraints on the basis of health-risk considerations is very important. Context of application – What is meant precisely by “source” is not straightforward and is fundamental. Most of the discussions about “sources” in, for example, ICRP77 (e.g. para. 42 and 44) and ICRP82 (para. 2 and 11) are about the general concepts and lack supporting discussions and analyses (with suitable references) of the specific cases that would help explain the international relevance of these values and their context of application. This type of information, necessary for an open and transparent international debate of the matter, is notably missing. The need for open and transparent international debate – We emphasise that practically none of the 30 or so post-ICRP60 dose constraints (including the introduction of the 0.3 and 0.1 mSv/y values) has been truly debated internationally with the competent and qualified representatives of the concerned parties. We recognize that ICRP60 was subject to such a debate, and we would expect that any important post-ICRP60 matters deserve the same attention. We point out that even if some values (below 1 mSv/y) may have been used as dose constraints in some jurisdictions for various specific reasons, this does not make the case to extrapolate them to the international scene. The conclusion that arises from this key practical example is that the status of the 0.1 and 0.3 mSv/y dose constraints (and likely also the remaining 30 or so post-ICRP60 dose constraints) has not yet been openly and transparently debated internationally. The post-ICRP60 dose constraints appear more relevant to the former ICRP’s “DAD” philosophy (Decide, Announce, Defend) than to the more recent ICRP’s “MUM” philosophy (Meet, Understand, Modify). MUM is now internationally understood as essential to the ICRP’s approach with regard to any proposed important changes and should be the operative theme in current international discussions and debates. *** EARLIER COMMENTS FROM THE WORLD NUCLEAR ASSOCIATION SENT TO ICRP (Feb 2, 2003) *** February 2, 2003 Dr. Abel Gonzales, International Atomic Energy Agency Wagramer Strasse 5, P.O. Box 100, A-1400 Vienna Austria Email: a.j.gonzalez@iaea.org Dr. Norm Gentner, United Nations Scientific Committee on the Effects of Atomic Radiation Wagramer Strasse 5, P.O. Box 100, A-1400 Vienna Austria Email: norman.gentner@unvienna.org Dr. Roger Clarke and Dr. Lars-Erik Holm, International Commission on Radiological Protection Email: clarke.rogerh@btopenworld.com Email: lars-erik.holm@ssi.se Re : WNA Key Messages on Radiological Protection of the Environment/Non-Human Species Dear Dr. Gonzales, Dr. Gentner, Dr. Clarke and Dr. Holm: Following last October’s IAEA-sponsored international conference in Stockholm on the protection of non-human species, WNA has drafted some key messages with regard to international developments on this challenging topic. Because we intend that these key messages be consistent with the overall perception of leading individuals and institutions in this process, we would appreciate your review of the attached pages and any comments you may have. We see great merit in the IAEA/ICRP initiatives seeking to incorporate regular stakeholder input in the development of the future system of radiological protection for non-human species. Similarly, we see clear benefits from the development of a joint IAEA/UNSCEAR/ICRP “road map” that would provide clear direction and co-ordination of activities as the process moves forward. As this occurs, WNA will continue to participate actively in the international debate in general and specifically in discussion within the technical community. Our aim is to ensure that nuclear industry expertise and data contribute constructively to future developments. Yours sincerely, Sylvain Saint-Pierre Director for Environment and Radiological Protection cc: WNA Director General John Ritch World Nuclear Association Radiological Protection of the Environment/Non-Human Species – Key Messages 1. There is wide agreement that the current system of radiological protection has in practice provided appropriate standards of environmental protection, but also wide acknowledgement that the system needs to be further developed for completeness in order to fill a conceptual gap (i.e., exposure of non-human species where human exposure is not the predominant concern) and to address some specific outstanding situations. An effective practical solution that fills the conceptual gap and that can be scaled to address specific outstanding situations should: · Realistically characterize the environmental risk posed by a specific set of practices; · Be sufficiently flexible to fit a wide range of situations and be commensurate with any potential risk so as to ensure that resource expenditures are in reasonable balance with benefits; and · Improve clarity and transparency regarding how and to what extent the environment is being protected. 2. The IAEA, ICRP and UNSCEAR have an important leadership role in ensuring a clear direction for future work and the co-ordination of activities to develop and implement a sound international framework for environmental radiological protection. In exercising this leadership, the three organisations should collaborate on a joint “road map” that: · Describes a shared vision, clear objectives and a path forward for developing and implementing a framework; · Specifies how stakeholders can participate in development and implementation of the framework; and · Delineates a sequence of activities, milestones, timeframes and responsibilities for achieving the objectives – with progress reported regularly and transparently to the stakeholders. The WNA will continue to contribute actively to the international debate and to a discussion by the scientific community, with aim of ensuring that nuclear industry expertise and data contribute constructively to future developments. 3. The system of environmental protection must be shaped in an overall context in which the producers of nuclear power as a clean, beneficial source of energy act as stewards of environmental protection in conformity with stringent environmental standards. As a practical reality, this stewardship is currently working well: · The radiological impact of many nuclear sites, and power plants in particular, is often difficult to distinguish from background levels of radiation; · There is no evidence that radioactive discharges from nuclear sites, controlled to levels consistent with ICRP criteria for the protection of humans, have had any discernible effect on potentially affected ecosystems; and · Even for sites with the most significant historical discharges, currently available biota dose assessment methodologies indicate that dose rates are significantly below levels at which any effects would be expected. 4. Several additional points concerning current practice by the global nuclear industry bear emphasis: · The nuclear industry uses: o Extensive pollution controls based on the ALARA (“as low as reasonably achievable”) principle; o Sophisticated monitoring systems to ensure that radioactive discharges are kept well below authorized limits and that nuclear facilities are functioning normally; and o Industry-standard environmental monitoring programmes to detect and analyse any potential anomalies or trends in radiological levels in surrounding air, land and water, · The incremental environmental concentrations of radionuclides already accounted for in the controlled release of radioactive discharges from nuclear facilities are well below the concentration levels at which any effect would be expected on non-human species. · There are no indications from the recent IAEA Stockholm international conference or earlier international events that IAEA and UNSCEAR current international guidance values for the protection of non-human species (i.e., 1 and 10 mGy/day) would not be appropriate. Experience to date shows that situations with exposure to non-human species that would approach these guidance values are extremely rare, and evidence of observable harm in these rare cases has not been demonstrated. · There is no evidence to undercut the long-standing premise that protecting the environment as a whole can best be achieved through a system of radiological protection centred on humans. Therefore, new complementary provisions directed at protecting non-human species should not focus on routine discharges into the general environment but rather on specific outstanding situations involving significant discharges into the environment in particular local settings that tend to favour the accumulation of radionuclides. In such situations, it is quite likely that a screening demonstration of a “finer” level of protection would be sufficient, without need for extra monitoring or for extra provisions explicitly aimed at protecting non-human species by controlling radioactive discharges. 5. Any future system of protection that fills the “conceptual gap” should: · Be based on a scientific framework that assesses natural and man-made radioactivity on a common basis; · Be capable of simple and practical application; · Not impose a disproportionate burden on the beneficial uses of nuclear technology, including the availability of nuclear energy, and not require blanket application across sites with evident negligible environmental impact; and · Be focused instead on specific outstanding situations with the aim of protecting species, populations and ecosystems. WNA Radiological Protection Working Group / February 2, 2004 *** EARLIER COMMENTS FROM THE WORLD NUCLEAR ASSOCIATION SENT TO ICRP (March 24, 2005) *** 24 March 2005 Dr. Roger Clarke and Dr. Lars-Erik Holm International Commission on Radiological Protection SE-171 16 Stockholm Sweden Subject: WNA’s RPWG Key Review Comments on ICRP C1 Task Group Report Dear Dr. Clarke and Dr. Holm, The World Nuclear Association (WNA) is pleased to provide its key review comments on the subject ICRP draft report entitled: “Low-dose Extrapolation of Radiation related Cancer Risk – Draft of Dec 10, 2004” These review comments were prepared by the WNA’s Working Group on Radiological Protection (RPWG). The RPWG is composed of experienced RP professionals drawn from a wide range of nuclear industry sectors in various countries who have been constructively involved in the ongoing international RP debate. Review Comments 1. The draft report seems to be a comprehensive compilation of the relevant scientific information and analysis on low doses which, as mentioned in the report introduction, roughly correspond to doses of about 10 mSv. 2. This report structures this scientific information well and makes progress in analysing it. However, given that some significant on-going scientific works that underpin the basic knowledge on low doses are in the process of being updated (e.g. UNSCEAR and US NAS), it would seem more logical to complete these updates first and then to have their findings accounted for in the development of the C-1 report. Otherwise, this report may in a relatively short timeframe be considered incomplete, if not obsolete, and would not serve effectively as a primary reference for the scientific basis of the next generation of ICRP recommendations. Given this, while our review comments are preliminary, we believe that they can add value and constructively contribute to the development of the current draft report. 3. The report repeatedly put forward a rationale in favour of the so-called “linear, no-threshold” (LNT) hypothesis. Down to ‘low doses’ and even lower, this rationale tends to be weaker as scientific data and evidence are also weaker. However, it is noted that the report comparisons to the extreme and idealistic notion of a universal scientific threshold - below which there would be absolutely zero risk! – add an extra level of weakness. The report would benefit from being more neutral and cautious here, including for the related conclusions. Notwithstanding this, the fact remains that at such low levels, the question of whether ‘purely’ scientifically valid relations (linear or other) or a universal threshold can be found or not, is rather a ‘purely’ scientific matter that cannot provide a legitimate basis for sound public RP policy. 4. The report’s overall conclusion seems partly unclear: “… the evidence as a whole does not favour the existence of a universal threshold, and there seems to be no particular reason to factor the possibility of a threshold into risk calculations for purposes of radiation protection.” (p.12) What is the precise meaning of the second clause? Can it mean that for radiation protection purposes, there would be no room for a practical threshold (not necessarily ‘purely’ scientifically valid) below which risk calculations would be considered as irrelevant for sound public RP policy? If so, it can be easily argued (e.g. based on ALARA, and its essential aim of achieving a reasonable balance of risks and benefits) that down to very low and extremely low doses, such a practical threshold does have an important role to play in making sound RP policies even if it would bear some tiny theoretical risks. – The WNA Position Statement on “Risks of Low-Dose Ionising Radiation” (see the attached electronic “pdf” file) provides a broad perspective on this topic, and ends by emphasising “the need to establish a consistent international approach to defining a level of dose below which it is widely deemed legitimate to maintain that an individual is adequately protected from ionising radiation, whether natural or man-made.” Moreover, it adds that “At such a low level – below which there would be an agreed absence of valid health concerns – it would be unjustified to allocate more resources to controlling sources of small radiation exposure because any such effort could only impair the many peaceful uses of nuclear technology, from which much human benefit is attained.” 5. The report mentions and discusses some important non-scientific issues in relation to low doses and the related thresholds, but this information is generally not well focused, is sometimes unclear or lacks coherence, and overall tends to miss some of the most essential points. The quotes from the draft report that are reproduced herein in Annex A illustrate the kinds of non-scientific issues that we have noted in the draft report. One essential point that is notably missed is a discussion of the important role that a practical threshold should play in making sound RP policies. The overall conclusion that can be derived from this is that the C-1 report is most likely not a suitable place for discussing and addressing non-scientific issues and for making judgment calls on practical radiological protection purposes, in particular on those that relate to public policies and practical thresholds. The fact that ICRP leadership in the low dose debate plays an important role in improving public understanding and perception of radiation and of its associated risks is another key factor in suggesting that non-scientific issues are best to be addressed outside of the scientific scope of the C-1 draft report. Otherwise, there would be a real risk that scientific issues become unduly discounted relative to increasing social concerns about lower radiation risk that would not be based on any rationale. What seems more appropriate here is that the matter of adopting a practical threshold (corresponding to some tiny theoretical risk) on the basis of a reasonable balance between scientific and non-scientific issues should be seriously considered by ICRP (at the upper level - e.g. Committee 4 or the Main Commission itself). If there would be added value, this process could possibly include seeking further scientific input from the C-1 Task Group on the practical threshold considered. 6. Direct or indirect suggestions in the Conclusions that, based on epidemiological or experimental carcinogenesis studies, there is evidence of radiation risk down to doses of the order of 10 mGy, and even lower doses of the order of 1 mGy warrant further explanations and evidence. What is missing here is a balanced discussion that would present the weight of evidence that supports linearity down to about 100 mGy against the much more limited evidence and data that would support linearity at lower doses. 7. The report does not seem to include an assessment of data on populations that live in high background radiation areas - that precisely correspond to the low dose levels that are of prime interest in this study. This potential shortcoming should be thoroughly examined and, if relevant, it should be well addressed in the next draft report. 8. Considering the emerging topics of radiation-related adaptive response, genomic instability, and bystander effects, we note that the current level of understanding is insufficient and that further studies are needed. We appreciate this opportunity to contribute to the ICRP’s open consultation process, and we look forward to working further with you in exploring ways to improve the current RP system. Yours sincerely, Sylvain Saint-Pierre Director for Environment and Radiological Protection ANNEX A The following quotes from the draft report illustrate the kinds of non-scientific issues that we have noted in the draft report: - Quantitative uncertainty approach: “Central to the approach is recognition of the fact that radiation protection is a political process,…” (p.16) - Avoiding or benefiting from radiation-related risk: “The problem is inherently political…” (p.21) - Estimation of cancer risk following radiation exposure: “Public and regulatory interest is usually with exposures at radiation doses far lower than those at which useful information about risk can be obtained by studying populations which such exposures.” (p.21) - Estimation of risk at low doses and low dose rates: “Most public concern is with exposures to less than 50 mSv,…” (p.31)