Environmental Radiation Protection

Transcription

1 Environmental Radiation Protection Dr Mike Wood University of Salford, UK 1

2 Senior Lecturer Who am I? Environmental Consultant Capacity Builder Researcher 15 years in environmental radiation protection National, European and international TREE Principal Investigator 2

3 Major UK-funded research project Oct 2013 Sept 2018, Chernobyl-based International environmental radiation protection Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP 3

4 Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP 4

5 1977 ICRP statement The Commission..believesthat if man is adequately protected then other living things are also likely to be sufficiently protected ICRP Statement The Commission believesthat 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. No requirement to assess the impact on wildlife of radionuclides released into the environment Marine conservation areas Sellafield SSSI & LNR 5

6 Is that OK? Is that OK? c.year 2000 various national regulators begin to require environmental radiological assessments: USA, UK, Sweden, Finland, Canada... 6

7 ICRP, from 2003 the Commission.believes that it is necessary to consider a wider range of environmental situations, irrespective of any human connection with them.[and]...assess.effects, for nonhuman species. The fundamental safety objective is to protect people and the environmentfrom harmful effects of ionizing radiation National (e.g. UK) EC, EC Birds Directive 79/409/EEC UK Parliament, Wildlife and Countryside Act EC, EC Habitats Directive 92/43/EEC UK Parliament, Conservation (Natural Habitats) Regulations Requires demonstration of protection of designated sites and species from hazardous substances Interpreted (in UK) to include ionising radiation Environmental radiation protection assessments are required 7

8 Public perception (ca ) ( ) Public perception (ca ) Increasingly educated public Heightened awareness of risk ( ) 8

9 Points to note ERP primarily a regulatory response Also recognises public interest No expectation that regulateddischarges will result in significant environmental impacts Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP 9

10 A Generic Framework for Environmental Radiation Risk Assessment Stakeholder input 10

11 Target of protection = Population 11

12 TIER 1 Risk screening Tiered approach TIER 2 Generic quantitative TIER 3 Detailed Quantitative Environmental and health protection Data needs Conservatism Resources TIER 1 Risk screening Tiered approach TIER 2 Generic quantitative TIER 3 Detailed Quantitative Environmental and health protection Data needs Level of detail proportionate with risk Conservatism Resources 12

13 ERICA Tool ERICA download ERICA Training courses and learning materials +environment+-+sharing+knowledge Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP 13

14 Transfer & Dose ICRP 108 Reference Animals & Plants Reference Organisms Mammal large Mammal small-burrowing Flying insect Annelid Bird Amphibian Pelagic fish Benthic fish Crustacean Tree Grasses & herbs Macroalgae 14

15 Transfer simplified. Most approaches use concentration ratios (CR) -1 CR Activity concentration in biota whole body (Bq kg fresh weight) = Activity concentration media (filtered water (Bq l ), soil (Bq kg dry weight) or air (Bq m 3 )) Estimating activity concentrations Bq/kg Bq/kg x CR = 15

16 Freshwater Radionuclide Fish Vascular plant Mollusc Reptile Algae Phytoplankton Crustacean Insect larvae Insect Zooplankton Mammal Amphibian Cs Sr Am Cm Pu Ra Ce Co Mn U Pb Cd Po Sb Se I Ni Th Zr Eu Ru Cl P Np S Tc Te Ag Nb n 10 n>10<20 n>20<100 n

17 Dose Units of absorbed dose (Grays) = Energy deposited (J kg -1 ) No Sieverts (Sv) for wildlife ERICA exposure scenarios Marine 1 Terrestrial 5 Freshwater

18 Reference organism geometries Organism shapes approximated by ellipsoids, spheres or cylinders of stated dimensions Homogeneous distribution of radionuclides within the organism: organs are not considered Organism immersed in uniformly contaminated medium Dose rate averaged over organism volume Dose conversion coefficients (DCC) DCC used to calculate dose rate from Bq/kg Both internal and external DCCs used Units are µgy/h per Bq/kg 18

19 Calculating dose x DCC int x DCC ext Total dose rate 19

20 (Whicker and Schultz, 1982) Radiation Effects - wildlife Early Mortality premature death of organism Reproduction is thought to be a more sensitive effect than mortality Morbidity reduced physical well being including effects on growth and behavior Reproductive Success reduced fertility and fecundity These categories of radiation effects are similar to the endpoints that are often used for risk assessments of other environmental stressors, and are relevant to the needs of nature conservation and other forms of environmental protection 20

21 Use of benchmarks Generally NOT used as limits Indicate when should refine assessment etc. The ERICA 10 µgy/h is for screening assessments only (Tiers 1 and 2) 21

22 Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP Acceptance - cost Additional cost for an already heavily regulated industry 22

23 Acceptance - why change? No proof that the protect man & you protect the environment belief was wrong Conflicting reports on effects 23

24 Chernobyl effect on insects 24

25 Into context ERICA no effect level Into context ERICA no effect level UK natural background 25

26 Into context ICRP expect effects ERICA no effect level UK natural background Into context Terrestrial population no-effect ICRP expect effects ERICA no effect level UK natural background 26

27 ? 27

28 Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP Some sources of information... ICRP Committee 5 on Protection of the Environment ( IAEA EMRAS/EMRAS II ( MODARIA ( EC STAR ( TREE Project ( 28

29 Some sources of Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP 29

30 Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP 30

31 Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP 31

32 Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP 32

33 Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP 33

34 Learning outcomes By the end of this session you should be able to: Identify drivers for environmental radiation protection (ERP) Describe a generic framework for environmental radiation risk assessment (ERRA) Explain some of the science that underpins the generic framework Identify challenges in ERRA Locate relevant sources of information on ERP Questions??? 34