ICRP Publication 124
Protection of the Environment under Different Exposure Situations
Recommended citation
ICRP, 2014. Protection of the Environment under Different Exposure Situations. ICRP Publication 124. Ann. ICRP 43(1).
Authors on behalf of ICRP
R.J. Pentreath, J. Lochard, C-M. Larsson, D.A. Cool, P. Strand, J. Simmonds, D. Copplestone, D. Oughton, E. Lazo
Abstract - In this report, the Commission describes its framework for protection of the environment and how it should be applied within the Commission’s system of protection. The report expands upon its objectives in relation to protection of the environment, in so far as it relates to the protection of animals and plants (biota) in their natural environment, and how these can be met by the use of Reference Animals and Plants (RAPs); their Derived Consideration Reference Levels (DCRLs), which relate radiation effects to doses over and above their normal local background natural radiation levels; and different potential pathways of exposure. The report explains the different types of exposure situations to which its recommendations apply; the key principles that are relevant to protection of the environment; and hence how reference values based on the use of DCRLs can be used to inform on the appropriate level of effort relevant to different exposure situations. Further recommendations are made with regard to how the Commission’s recommendations can be implemented to satisfy different forms of environmental protection objectives, which may require the use of representative organisms specific to a site, and how these may be compared with the reference values. Additional information is also given with regard to, in particular, communication with other interested parties and stakeholders. Issues that may arise in relation to compliance are also discussed, and the final chapter discusses the overall implications of the Commission’s work in this area to date. Appendices A and B provide some numerical information relating to the RAPs. Annex C considers various existing types of environmental protection legislation currently in place in relation to large industrial sites and practices, and the various ways in which wildlife are protected from various threats arising from such sites.
© 2014 ICRP. Published by SAGE.
Keywords: Radiation; Exposure situations; Environmental protection; Biota.
AUTHORS ON BEHALF OF ICRP R.J. PENTREATH, J. LOCHARD, C-M. LARSSON, D.A. COOL, P. STRAND, J. SIMMONDS, D. COPPLESTONE, D. OUGHTON, E. LAZO
Key Points: Not included in this publication
Executive Summary
(a) Within the Commission’s overall framework for protection against ionising radiation, the Commission has now broadened its scope by introducing a new requirement, that of protecting the environment. The present report describes the Commission’s framework for protection of the environment and how it should be applied within the Commission’s system of protection.
(b) The Commission’s aims in terms of environmental protection are to prevent or reduce the frequency of deleterious radiation effects on biota to a level where they would have a negligible impact on the maintenance of biological diversity; the conservation of species; or the health and status of natural habitats, communities, and ecosystems. The biological endpoints of most relevance are therefore those that could lead to changes in population size or structure. Due to the immense variety of biota, and their presumed response to radiation, any credible system needs to have some key points of reference that provide some form of auditable trail that links the basic elements of the framework together, or at least could do so if further data were forthcoming and it is feasible to obtain such data. The Commission therefore developed a small set of 12 Reference Animals and Plants (RAPs), plus their relevant databases, for a few types of organisms that are typical of the major environments. The RAPs were described to the generality of the taxonomic level of Family, because this is the highest taxonomic level at which the biological features of an animal or plant of relevance to the effects of radiation can be assumed to be relatively constant. They are essentially reference models.
(c) Derived Consideration Reference Levels (DCRLs) that are specific to each of the different types of RAPs have also been defined. A DCRL can be considered as a band of dose rate, spanning one order of magnitude, within which there is some chance of deleterious effects from ionising radiation occurring to individuals of that type of RAP. Thus, when considered together with other relevant information, DCRLs can be used as points of reference to inform on the appropriate level of effort that should be expended on environmental protection, dependent on the overall management objectives, the exposure situation, the actual fauna and flora present, and the numbers of individuals thus exposed.
(d) The Commission therefore recommends that DCRLs should be used under all circumstances where there is, or may be, an incremental environmental exposure of significance above the natural background locally experienced by the relevant biota. In planned exposure situations, the lower boundary of the relevant DCRL band should be used as the appropriate reference point for protection of different types of biota within a given area during the planning of controls to a source. Due to the possibility of multiple sources affecting the same biota, or for any residual exposures arising from previous sources, consideration also needs to be given to possible cumulative impacts.
(e) For existing exposure situations, and in emergency exposure situations where control of the source has not been obtained, if the dose rates are above the relevant DCRL band, the Commission recommends that the aim should be to reduce exposures to levels that are within the DCRL bands for the relevant populations, with full consideration of the radiological and non-radiological consequences of so doing. If dose rates are within the bands, the Commission believes that consideration should be given to reduce exposures, assuming that the costs and benefits are such that further efforts are warranted. Thus, in the case of existing exposure situations, the DCRLs should be used as the criteria for mitigating environmental exposures.
(f) As the RAPs are, by definition, points of reference, it may also be necessary to identify representative organisms relevant to each situation. These may be extremely similar to RAPs or may be different. In some cases, there will be little choice in selection because this may have been undertaken previously by way of other existing legislation. Nevertheless, differences between such biota and the RAPs should be quantifiable in relation to their basic biology, dosimetry, or radiation effects, and such differences need to be noted and taken into account. The extent to which such factors need to be applied, and their relevant impact on the final decision, will depend on the nature of the implementation and application of the planning process relevant to protection of the environment. As other regulatory bodies are likely to be involved, such as those responsible for wildlife management, it is essential to have a clearly set out logical link between any radioactive releases and potential risk of biological effects (for which the RAP framework should be a starting point), and a clearly laid out strategy by which the relevant stakeholders can be engaged in the decision-making process.
(g) With regard to responding to an actual emergency event, or accidental release of radionuclides into the environment, consideration of environmental protection may not be an immediate priority, depending on the extent to which human exposures, or human food chains, are likely to be affected. However, even where human exposure concerns predominate, consideration should be given to the environmental consequences of the possible options available to achieve the adequate level of human protection.
(h) After the occurrence of an accident, the framework of the DCRLs, and the set of indicative population impacts relative to the doses they receive, may be useful in communicating the implications of the situation to stakeholders, particularly in relation to environmental conditions where humans have been removed from the area, and food chains leading to human exposure have been severed. The concept of such severe-effect reference levels is often used within the chemical industry. The Commission notes that this type of level could be considered to be approximately equivalent to a band of doses two orders of magnitude above the DCRL band. With the passage of time immediately following an accidental release, information can be conveyed to the public in terms of an assessment of the environmental situation relative to a predetermined reference point, and thus the results of mitigation actions, or simply the effect of natural events, can be readily assessed and evaluated.
(i) Wherever possible, protection of the environment from a source should complement controls to protect the public, and not add unnecessarily to its complexity. The Commission therefore believes that, having essentially clarified the basis upon which decisions relating to protection of the environment can be made by way of a framework relating exposure to dose, and dose to effect, for different types of organisms (the set of RAPs), the demonstration of protection of both humans and nonhuman species as a result of normal planned exposure situations could well be integrated in a relatively simple manner, based solely on estimations (at the design stage) and measurements (during operation) of concentrations of radionuclides in the environment.
(j) The practical implementation of these recommendations will be kept under review by the Commission, and any future revisions will be made in light of this experience.
ICRP, 2014. Protection of the Environment under Different Exposure Situations. ICRP Publication 124. Ann. ICRP 43(1).
Authors on behalf of ICRP
R.J. Pentreath, J. Lochard, C-M. Larsson, D.A. Cool, P. Strand, J. Simmonds, D. Copplestone, D. Oughton, E. Lazo
Abstract - In this report, the Commission describes its framework for protection of the environment and how it should be applied within the Commission’s system of protection. The report expands upon its objectives in relation to protection of the environment, in so far as it relates to the protection of animals and plants (biota) in their natural environment, and how these can be met by the use of Reference Animals and Plants (RAPs); their Derived Consideration Reference Levels (DCRLs), which relate radiation effects to doses over and above their normal local background natural radiation levels; and different potential pathways of exposure. The report explains the different types of exposure situations to which its recommendations apply; the key principles that are relevant to protection of the environment; and hence how reference values based on the use of DCRLs can be used to inform on the appropriate level of effort relevant to different exposure situations. Further recommendations are made with regard to how the Commission’s recommendations can be implemented to satisfy different forms of environmental protection objectives, which may require the use of representative organisms specific to a site, and how these may be compared with the reference values. Additional information is also given with regard to, in particular, communication with other interested parties and stakeholders. Issues that may arise in relation to compliance are also discussed, and the final chapter discusses the overall implications of the Commission’s work in this area to date. Appendices A and B provide some numerical information relating to the RAPs. Annex C considers various existing types of environmental protection legislation currently in place in relation to large industrial sites and practices, and the various ways in which wildlife are protected from various threats arising from such sites.
© 2014 ICRP. Published by SAGE.
Keywords: Radiation; Exposure situations; Environmental protection; Biota.
AUTHORS ON BEHALF OF ICRP R.J. PENTREATH, J. LOCHARD, C-M. LARSSON, D.A. COOL, P. STRAND, J. SIMMONDS, D. COPPLESTONE, D. OUGHTON, E. LAZO
Key Points: Not included in this publication
Executive Summary
(a) Within the Commission’s overall framework for protection against ionising radiation, the Commission has now broadened its scope by introducing a new requirement, that of protecting the environment. The present report describes the Commission’s framework for protection of the environment and how it should be applied within the Commission’s system of protection.
(b) The Commission’s aims in terms of environmental protection are to prevent or reduce the frequency of deleterious radiation effects on biota to a level where they would have a negligible impact on the maintenance of biological diversity; the conservation of species; or the health and status of natural habitats, communities, and ecosystems. The biological endpoints of most relevance are therefore those that could lead to changes in population size or structure. Due to the immense variety of biota, and their presumed response to radiation, any credible system needs to have some key points of reference that provide some form of auditable trail that links the basic elements of the framework together, or at least could do so if further data were forthcoming and it is feasible to obtain such data. The Commission therefore developed a small set of 12 Reference Animals and Plants (RAPs), plus their relevant databases, for a few types of organisms that are typical of the major environments. The RAPs were described to the generality of the taxonomic level of Family, because this is the highest taxonomic level at which the biological features of an animal or plant of relevance to the effects of radiation can be assumed to be relatively constant. They are essentially reference models.
(c) Derived Consideration Reference Levels (DCRLs) that are specific to each of the different types of RAPs have also been defined. A DCRL can be considered as a band of dose rate, spanning one order of magnitude, within which there is some chance of deleterious effects from ionising radiation occurring to individuals of that type of RAP. Thus, when considered together with other relevant information, DCRLs can be used as points of reference to inform on the appropriate level of effort that should be expended on environmental protection, dependent on the overall management objectives, the exposure situation, the actual fauna and flora present, and the numbers of individuals thus exposed.
(d) The Commission therefore recommends that DCRLs should be used under all circumstances where there is, or may be, an incremental environmental exposure of significance above the natural background locally experienced by the relevant biota. In planned exposure situations, the lower boundary of the relevant DCRL band should be used as the appropriate reference point for protection of different types of biota within a given area during the planning of controls to a source. Due to the possibility of multiple sources affecting the same biota, or for any residual exposures arising from previous sources, consideration also needs to be given to possible cumulative impacts.
(e) For existing exposure situations, and in emergency exposure situations where control of the source has not been obtained, if the dose rates are above the relevant DCRL band, the Commission recommends that the aim should be to reduce exposures to levels that are within the DCRL bands for the relevant populations, with full consideration of the radiological and non-radiological consequences of so doing. If dose rates are within the bands, the Commission believes that consideration should be given to reduce exposures, assuming that the costs and benefits are such that further efforts are warranted. Thus, in the case of existing exposure situations, the DCRLs should be used as the criteria for mitigating environmental exposures.
(f) As the RAPs are, by definition, points of reference, it may also be necessary to identify representative organisms relevant to each situation. These may be extremely similar to RAPs or may be different. In some cases, there will be little choice in selection because this may have been undertaken previously by way of other existing legislation. Nevertheless, differences between such biota and the RAPs should be quantifiable in relation to their basic biology, dosimetry, or radiation effects, and such differences need to be noted and taken into account. The extent to which such factors need to be applied, and their relevant impact on the final decision, will depend on the nature of the implementation and application of the planning process relevant to protection of the environment. As other regulatory bodies are likely to be involved, such as those responsible for wildlife management, it is essential to have a clearly set out logical link between any radioactive releases and potential risk of biological effects (for which the RAP framework should be a starting point), and a clearly laid out strategy by which the relevant stakeholders can be engaged in the decision-making process.
(g) With regard to responding to an actual emergency event, or accidental release of radionuclides into the environment, consideration of environmental protection may not be an immediate priority, depending on the extent to which human exposures, or human food chains, are likely to be affected. However, even where human exposure concerns predominate, consideration should be given to the environmental consequences of the possible options available to achieve the adequate level of human protection.
(h) After the occurrence of an accident, the framework of the DCRLs, and the set of indicative population impacts relative to the doses they receive, may be useful in communicating the implications of the situation to stakeholders, particularly in relation to environmental conditions where humans have been removed from the area, and food chains leading to human exposure have been severed. The concept of such severe-effect reference levels is often used within the chemical industry. The Commission notes that this type of level could be considered to be approximately equivalent to a band of doses two orders of magnitude above the DCRL band. With the passage of time immediately following an accidental release, information can be conveyed to the public in terms of an assessment of the environmental situation relative to a predetermined reference point, and thus the results of mitigation actions, or simply the effect of natural events, can be readily assessed and evaluated.
(i) Wherever possible, protection of the environment from a source should complement controls to protect the public, and not add unnecessarily to its complexity. The Commission therefore believes that, having essentially clarified the basis upon which decisions relating to protection of the environment can be made by way of a framework relating exposure to dose, and dose to effect, for different types of organisms (the set of RAPs), the demonstration of protection of both humans and nonhuman species as a result of normal planned exposure situations could well be integrated in a relatively simple manner, based solely on estimations (at the design stage) and measurements (during operation) of concentrations of radionuclides in the environment.
(j) The practical implementation of these recommendations will be kept under review by the Commission, and any future revisions will be made in light of this experience.
