Presentation on theme: "Centre for Ecology & Hydrology - Lancaster October 2011."— Presentation transcript:
Centre for Ecology & Hydrology - Lancaster October 2011
Historical perspective of environmental radiological protection Why this has changed - prime motivations International initiatives in key international bodies The UK perspective Comparison with chemicals
‘ Although the principal objective of radiation protection is the achievement and maintenance of appropriately safe conditions for activities involving human exposure, the level of safety required for the protection of all human individuals is thought likely to be adequate to protect other species, although not necessarily individual members of those species. The Commission therefore believes that if man is adequately protected then other living things are also likely to be sufficiently protected. ’ ICRP, 1977
“ 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. ICRP, 1991
Human radiological protection: Focus on worker/most exposed individual Environment more as a route for transfer to humans Incomplete ecological information What’s the protection goal? Evidence needed for or against ICRP statement
Lack of demonstration that the environment is being protected May not be valid for some environments (e.g. those with no humans) Incompatible with management of other environmental chemical stressors Requirement for assessment under some national legislation
ICRP UNSCEAR Member States EU recommendations evidence provision establishing standards
ICRP 1977 – statement appears ICRP 1991 – recognise individuals may be impacted ICRP 2007 – Recommendations include need to consider environment and introduce ‘RAP Framework’ UNSCEAR (1996, 2011) Reports on Effects of Ionizing Radiation to Biota USA, Canadian, EU-Projects ( ) Scientific base Development of frameworks IAEA (2005) 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”
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”
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
Planned, Existing and Emergency exposure situations Environmental radionuclide concentrations Reference Male & Female 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 using representative individuals and representative organisms
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
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 RADIONUCLIDE SOURCE ECOLOGICAL PARAMETERS
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.”
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
As in its 1996 recommendations, UNSCEAR considers that chronic dose rates of less than 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
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
Biota Co-ordination Group Revision of Basic Safety Standards Approaches Environmental Modelling for Radiation Safety Application Technical cooperation on wildlife regulation RER Plan of Activities on Protection of the Environment 2005 IAEA Safety Fundamentals (2006)
Protection of the environment (extracts) Protection of people and the environment against radiation risks associated with the operation of facilities and the conduct of activities - and in particular, protection against such risks that may transcend national borders and may persist for long periods of time – is important to achieving equitable and sustainable development ----Trends also indicate the need to be able to demonstrate (rather than to assume) that the environment is protected against effects of industrial pollutants, including radionuclides, in a wider range of environmental situations, irrespective of any human connection.---- Adopt an integrated perspective to ensure the sustainable use of natural resources for agriculture, forestry, fisheries and tourism - now and in the future. BSS designed to identify the protection of the environment as an issue necessitating assessment, while allowing for flexibility in incorporating decision making processes the results of environmental assessments that are commensurate with the radiation risks.
Requirements Consider Protection of the Environment Registration and licensing Setting discharge limits Monitoring Remediation Protection of the environment is one factor during optimization in existing and emergency exposure situations => Associated Safety Guides and Safety Report under development
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 from ICRP Task Group
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 installations 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
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
Euratom Basic Safety Standards on 29 September 2011 the European Commission adopted the Proposal for a Council Directive laying down basic safety standards for protection against the dangers arising from exposure to ionising radiation [COM(2011)593]. Chapter IX: Protection of the Environment Euratom projects FASSET ERICA PROTECT FP7 – STAR Network
Chapter IX: Protection of the environment This chapter, in line with the broader scope of the Directive as in the International Basic Safety Standards, aims to provide a means to demonstrate compliance with environmental criteria. While the ICRP has published a methodology for dose assessment for biota, a publication on the application of criteria is still awaited. Pending such further guidance, it is up to national authorities to assess the doses to representative animals and plants in terms of protection of the ecosystem. Appropriate technical measures also need to be taken to avoid the environmental consequences of an accidental release and to monitor existing levels of radioactivity in the environment, from the perspectives of both environmental protection and human health.
Article 76 Environmental Criteria Member States shall include, in their legal framework for radiation protection and in particular within the overall system of human health protection, provision for the radiation protection of non-human species in the environment. This legal framework shall introduce environmental criteria aiming to protect populations of vulnerable or representative non-human species in the light of their significance as part of the ecosystem. Where appropriate, types of practices shall be identified for which regulatory control is warranted in order to implement the requirements of this legal Framework.
Article 77- Authorised limits on discharges Member States’ competent authorities, when establishing authorised limits on discharges of radioactive effluents, in accordance with Article 65(2), shall also ensure adequate protection of non-human species. For this purpose, a generic screening assessment may be conducted to provide assurance that the environmental criteria are met. Article 78 - Accidental releases Member States shall require undertakings to take appropriate technical measures to avoid significant environmental damage in the event of an accidental release or to mitigate the extent of such damage. Article 79 – Environmental monitoring When establishing environmental monitoring programmes, or requiring such programmes to be carried out, Member States’ competent authorities shall include representative non-human species, if necessary, and also environmental media which constitute a pathway of exposure for members of the public.
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 Directive in the UK. The UK has interpreted the EC Birds & Habitats Directives as requiring assessments to determine that no authorised discharges of radioactivity will impact upon protected (Natura 2000) sites.
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
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
US DOE facilities are required to demonstrate annually that routine radioactive release from their sites are protective of non-human receptors DOE Order : In addition to providing protection to members of the public, it is DOE’s objective to protect the environment from radioactive contamination to the extent practical. Assessed against dose rate limits for different organism groups established to avoid measurable impairment of reproductive capacity Objective: to protect the terrestrial and aquatic environment, including populations of animals and plants within and beyond the boundaries of DOE sites ……
Sweden, UK, Canada & Finland – waste repositories England & Wales >700 authorisations impacting on (protected) Natura 2000 sites USDOE sites – assessment is an annual requirement U industry – (e.g. Canada, Australia) New build power plants (e.g. UK) Decommissioning (e.g. Lithuania)