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Brenda Howard (CEH) Historical perspective – previous ICRP guidance Why this has changed - prime motivations International initiatives at the EC, IAEA,

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Presentation on theme: "Brenda Howard (CEH) Historical perspective – previous ICRP guidance Why this has changed - prime motivations International initiatives at the EC, IAEA,"— Presentation transcript:

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2 Brenda Howard (CEH)

3 Historical perspective – previous ICRP guidance Why this has changed - prime motivations International initiatives at the EC, IAEA, ICRP and UNSCEAR Comparison with system for humans The situations in which assessments may be used Radiation protection of the environment in the UK Tiered assessments Comparison with chemicals The course

4 The Commission believes that the standard of environmental control needed to protect man to the degree currently thought desirable will ensure that other species are not put at risk. Occasionally, individual members of non-human species might be harmed, but not to the extent of endangering whole species or creating imbalance between species. At the present time, the Commission concerns itself with mankinds environment only with regard to the transfer of radionuclides through the environment, since this directly affects the radiological protection of man ICRP, 1991, Para. 16

5 Focus on worker/most exposed individuals Incomplete ecological information Limited evidence provided to support statement (in the context of the environment)

6 Focus on worker/most exposed individuals Incomplete ecological information Limited evidence provided to support statement Changing attitudes Late 1990s tools and techniques available Recognition of environmental risks (e.g. Rio) Conservation and protection drivers

7 Focus on worker/most exposed individuals Incomplete ecological information No evidence provided to support statement Changing attitudes Late 1990s tools and techniques available Recognition of environmental risks (e.g. Rio) Conservation and protection drivers The need to explicitly demonstrate no impact…

8 National legislation National interpretation of international legislation Various bodies – need to explicitly demonstrate/why different to chemicals IUR promoted need for an approach not based on humans OECD-NEA has highlighted the need for radiological assessment of non-human biota and supported tiered assessment approach

9 ICRP UNSCEAR Member States EU

10 ICRP 1977, 1990 Recommendations If there is compliance with radiation protection standards for man, other species are not put at risk UNSCEAR (1996) Report on Effects of Ionizing Radiation to Biota USA, Canadian, EU-Projects ( ) Scientific base Development of frameworks IAEA 2005 Setup of the Plan of Activities on Protection of the Environment IAEA Safety Fundamentals (2006) Principle 7:Protection of People and the environment, present and in the future, must be protected against radiation risks

11 Recommends the explicit consideration of Radiological Protection of the Environment ICRP recognised Need for advice and guidance Lack of consistency at an international level More proactive approach needed Complex nature of environmental protection Need to develop a clearer framework – C5 Assess exposure – dose – effect relationships Pragmatic approach No dose limits

12 Planned - current activities, new nuclear sites and U mines etc Not historic (yrs of discharge) Mostly for planned NPP and waste repositories (current or prospective discharges) Existing – exposure to natural radiation sources and contamination of areas by residual radioactive material Past activities that were never subject to regulatory control or were not regulated according to present requirements; An emergency, after the emergency exposure situation has been declared ended Residues from past activities for which there is no longer legally accountability Used in USA for previously contaminated sites Emergency – eg accidents, malevolent acts Low priority in acute phase

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14 Planned, Existing and Emergency exposure situations Environmental radionuclide concentrations Reference Male & Female Reference Person Dose limits, Constraints and Reference levels Reference Animals and Plants Derived Consideration Reference Levels Decision-making regarding public health and environmental protection for the same environmental exposure situation by way of representative individuals and representative organisms

15 RADIONUCLIDE SOURCE HABITS DATA REFERENCE PERSON IMPACT TOTAL ABSORBED DOSE PATHWAY OF EXPOSURE Application of a weighting factors for RBE & different tissues Compare predicted dose to known biological effects & dose limits

16 RADIONUCLIDE SOURCE HABITS DATA REFERENCE ANIMAL OR PLANT IMPACT TOTAL ABSORBED DOSE PATHWAY OF EXPOSURE Application of a weighting factors for RBE & different tissues Compare predicted dose to known biological or ecological effects & guideline values ECOLOGICAL PARAMETERS

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18 For human protection, the reference individuals and Reference Person are idealised models developed for the specific purposes of relating exposure to dose, and dose to effect. They do not represent any specific type of human being (the reference individuals are phantoms, and the Reference Person is a hermaphrodite), but nevertheless have to be discretely defined to serve their basic purpose. To be consistent with the original concept of Reference Man, a Reference Animal or Plant can be described as follows: A Reference Animal or Plant is a hypothetical entity, with the assumed basic biological characteristics of a particular type of animal or plant, as described to the generality of the taxonomic level of family, with defined anatomical, physiological, and life-history properties, that can be used for the purposes of relating exposure to dose, and dose to effects, for that type of living organism.

19 United Nations Scientific Committee on the Effects of Atomic Radiation Established in 1955 UN Scientific Committee reports to General Assembly Assesses global levels and effects of ionizing radiation Provides scientific basis for radiation protection Governments and organisations rely on Committee's estimates as the scientific basis for evaluating radiation risk and establishing protective measures

20 Report on Effects of radiation on the Environment in 1996 Limited available data Review of data, including Chernobyl Based largely on acute data Effects difficult to estimate due to long term recovery, compensatory behaviour and confounding environmental factors New report imminent

21 Acute doses

22 As in its 1996 recommendations, UNSCEAR considers that chronic dose rates of less than (about) 100 μGy h 1 to the most highly exposed individuals would be unlikely to have significant effects on most terrestrial communities; and that maximum dose rates of 400 μGy h 1 to any individual in aquatic populations of organisms would be unlikely to have any detrimental effect at the population level nominal Relative Biological Effectiveness (RBEs) of 10 for internally deposited alpha radiation and 1 for beta radiation were recommended

23 CategoryDose rateEffectsEndpoint Plant μGy h -1 Reduced trunk growth of pine treesMorbidity μGy h -1 Reduced numbers of herbaceous plantsMorbidity Fish μGy h -1 Reduction in testis mass and sperm production, lower fecundity, delayed spawning Reproductive 200 – 499 μGy h -1 Reduced spermatogonia and sperm in tissuesReproductive Mammals < 100 μGy h -1 No detrimental endpoints have been describedMorbidity, Mortality, Reproductive Generic ecosystems (terrestrial and aquatic) About 80 μGy h -1 A new statistical approach (species sensitivity distribution, SSD) was applied to radiation effects data to estimate the hazardous dose rate (HDR 5 ), the dose rate at which 95% of the species in the ecosystem are protected Morbidity, Mortality, Reproductive Overall summary of (illustrative) chronic effects data for plants, fish and mammals

24 Plan of Activities on Protection of the Environment 2005 After Stockholm conference in 2003 IAEA Safety Fundamentals (2006) Principle 7:Protection of People and the environment, present and in the future, must be protected against radiation risks Biota Co-ordination Group Revision of Basic Safety Standards Approaches Environmental Modelling for Radiation Safety Application Technical cooperation on wildlife regulation RER 7005

25 Introduction Protection of people and the environment Prevention of radiological effects on human health and on flora and fauna. Adopt an integrated perspective to ensure the sustainable use of natural resources for agriculture, forestry, fisheries and tourism - now and in the future. Requirements Consider Protection of the Environment Registration and licensing Setting discharge limits Protection of the environment is one factor during optimization in existing and emergency exposure situations => 3 Safety Guides and 1 Safety Report under development

26 Guidance for the implementation of radiation protection as recommended in the new BSS Exposures to public Exposures to environment How to apply radiation protection principles to exposures of the environment Justification, Limitation, Optimization Exposure situations Planned, existing, emergency Discuss the application of Derived Consideration Reference Levels => Input expected from a currently working ICRP Task Group

27 How to perform a Radiological Environmental Impact Assessment (REIA) Endpoints Models and methods Graded approach for the REIA Which efforts are needed for Small users Hospitals Nuclear installation How to use already existing data for REIA Data used for assessment of exposures to the public Results from environmental and source monitoring => Minimize efforts needed for assessing impacts to biota

28 Guidance to derive limits for radionuclide discharges to the environment Public exposure Environmental exposure Facilities and activities Nuclear installations Laboratories and hospitals Small users NORM =>Radiological impact to biota will be an integral part of the licensing process

29 Euratom Basic Safety Standards New BSS outline Title X: Protection of the Environment Euratom projects FASSET ERICA PROTECT FP7 – STAR Network CURRENT DRAFT only

30 Article 102 Member States shall include, in the legal framework for radiation protection, provision for the radiation protection of non-human species in the environment; this legal framework shall introduce environmental criteria aiming at the protection of populations of vulnerable or representative non-human species with regard to their significance as part of the ecosystem. Where appropriate, practices shall be identified for which regulatory control is warranted to implement the requirements in this legal framework and take account of appropriate environmental assessment criteria

31 Article 103 Member States' competent authorities, when establishing authorised limits on discharges of radioactive effluents, in accordance with Article 91 paragraph 2, shall also ensure adequate protection of non-human species; for this purpose a generic screening assessment may be conducted to provide reliance that the environmental criteria are met. Article 104 Member States shall require undertakings to take appropriate technical measures with the aim to avoid that in the event of an accidental release there will be significant environmental damage, or to mitigate the extent of such consequences. Article 105 While establishing environmental monitoring programmes, or requiring such programmes to be carried out, Member States' competent authorities shall include representative nonhuman species, if necessary, in addition to such environmental media which constitute a pathway of exposure to members of the public.

32 Recognise that in line with ICRP Publication 103, is a need for specific consideration of the exposure of biota where appropriate environmental criteria as well as dose constraints should be considered for the authorisation of discharges of radioactive effluent Support the development of a framework by ICRP C5

33 Recognise that in line with ICRP Publication 103, is a need for specific consideration of the exposure of biota where appropriate environmental criteria as well as dose constraints should be considered for the authorisation of discharges of radioactive effluent Support the development of RAPS and framework But feel that protection of the environment should not warrant a high level of regulatory control with demonstration of compliance proportionate to risk and allow enough time for transposition into national law

34 Europe: Habitats and Birds Directives On the conservation of natural habitats and of wild flora and fauna UK: Conservation (Natural Habitats) regulations 1994 Implements the Habitats Directive in the UK. Requires steps to maintain and restoration to favourable conservation status of habitats and species of Community level interest

35 Many approaches use a tiered assessment structure (in common with other areas of risk assessments) simple initial screening through to more refined assessments Also referred to as: staged or graded approaches

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37 Environmental and health protection Conservatism Resources TIER 1 Risk screening TIER 2 Generic quantitative TIER 3 Detailed Quantitative Data needs

38 Environmental and health protection Conservatism Resources TIER 1 Risk screening TIER 2 Generic quantitative TIER 3 Detailed Quantitative Data needs The level of detail in a risk assessment should be proportionate with the nature and complexity of the risk being addressed and consistent with decision-making needs

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40 Direct toxicity in soil and water: the assessment of toxicity thresholds for plants, invertebrates and microbial processes Higher organism health: comparison with Concentration in food eaten Ingested amount per unit liveweight of receptor species Concentration in organs of species compared to a risk quotient Human health: quantifying exposure to contaminants and assessing acceptable intake values

41 Soil solids Soil water M-DOM M-X M-soil M output = [M] aq x runoff M input g ha -1 a -1 H+H+ M z+ M aq

42 The critical load is the rate of deposition of a metal from the atmosphere, which at steady state, leads to the metal concentration in soils or water reaching a threshold for adverse effects (the critical limit)

43 Critical Load for Pb (g ha -1 y -1 ) Exceedance of Critical Load for Pb in Managed Broadleaf Woodland (ratio)

44 Assessments are being done – little formal training available - so we don't assume much prior knowledge We are being asked for advice on use of assessment tools The tools are only recently developed and there are various complexities and assumptions which need to be understood

45 Three tools freely available and usable by others Focus here on ERICA Tool developed by EC consortium RESRAD-BIOTA and R&D 128 mentioned when they have features not present in ERICA Tool EPIC FP4 FASSET FP4 ERICA FP5 PROTECT FP6


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