1. Ra226 Rn222 Po218 Pb214 Bi214 Terrestrial radionuclides An example from the U238 family α α α β β γ γ γ

2. Exposure to ionizing radiation Εξωτερική έκθεση Εσωτερική έκθεση Our body is penetrated each hour approximately by: 30 000 α- and β-particles from the radon daughters deposited in the respiratory tract 15 000 000 β-particles from the K40 in our tissues 200 000 000 γ-quanta from the terrestrial radionuclides 500 000 particles of cosmic origin Internal exposure External exposure

3. Average population doses through various pathways Estimates for USA, in μSv 3600 – total average Sources: 2000 – radon inhalation 390 – isotopes in our body 280 – terrestrial radiation 270 – cosmic radiation 10 – cosmogenic isotopes 600 – technogenic exposure ( mainly medical exposure )

4. Terrestrial radionuclides Th232 Series Th232 Ra228 Ac228 Th228 Ra224 Rn220 Po216 Pb212 Bi212 Po212 Typical concentrations : 20 – 200 Bq/kg U238 Series U238 Th234 Pa234m U234 Th230 Ra226 Rn222 Po218 Pb214 Bi214 Po214 Pb210 Bi210 Po210 Typical concentrations: 20 – 200 Bq/kg U235 Series U235 Th231 Pa231 Ac227 Th227 Ra223 Rn219 Po215 Pb211 Bi211 Tl207 Typical concentrations : 1 – 10 Bq/kg K40 Typical concentrations : 100 – 1000 Bq/kg 50 V, 87 Rb, 113 Cd, 115 In, 123 Te, 138 La, 142 Ce, 144 Nd, 147 Sm, 152 Gd, 174 Hf, 176 Lu, 187 Re, 190 Pt, 192 Pt, 209 Bi. Typical concentrations : very low, radiologically insignificant.

5. Concentrations of terrestrial radionuclides - Greece U238 Series Th232 Series K40 Reg. averages: 20-60 Bq/kg Reg. averages : 20-60 Bq/kg Reg. averages : 200-800 Bq/kg

6. Terrestrial radiation - Greece Regional dose rate averages, nGy h -1

7. Natural radionuclides in air U238 Series (Rn222 (radon) and its decay products) Rn222 Po218 Pb214 Bi214 Po214 Typical concentrations: 30 – 200 Bq/m 3 indoors 2 – 5 Bq/m 3 outdoors Th232 Series (Rn220 (thoron) and its decay products) Rn220 Po216 Pb212 Bi212 Po212 Typical concentrations : typically 10 times lower than those of Rn222 Cosmogenic isotopes C14, H3, Be7 10 Be, 26 Al, 36 Cl, 80 Kr, 32 Si, 39 Ar, 22 Na, 35 S, 37 Ar, 33 P, 32 P, 38 Mg, 24 Na, 38 S, 31 Si, 18 F, 39 Cl, 38 Cl

8. Natural radionuclides in marine water Typical concentrations, Bq/m 3 U238 - 33 H3 - 0.6 K40 - 11000 C14 - 5 Rb87 - 1100 Natural radionuclides in food Typical concentrations, Bq/kg ProductsΚ40 Ra226 Banana130 0.04 Brasil nuts210 40 - 250 Carrots1250.02 - 0.07 Potatoes1250.04 - 0.1 Beer 15 - Beef110 0.02 Drinking water 0 - 0.5 0 - 0.01

9. Natural radioactivity of food Total activity concentration, Bq kg -1 Product Total activity conc. Vegetable oil180 Bq kg -1 Milk 50 Alcoholic drinks 45 Beer 15 Drinking water 0.7 Brazil nuts500 Bananas110 Tea 15 Pastry 5 Pistachios 4.5

10. Natural radionuclides in human body Typical values, Bq Radionuclide Total Average daily activity intake U238 1.1 0.023 Th232 0.11 0.011 K40 4400 100 Ra226 1.1 0.08 C14 15000 280 H3 23 1 Po210 37

11. Technologically enhanced natural radioactivity (TENR) Radiologically important cases Uranium mining and milling Enhanced concentrations of U-series nuclides in areas of waste deposition Lignite power plants Air and soil pollution with lignite ash of enhanced natural radioactivity Building materials Use of lignite ash as cement component, phosphate byproducts, granites Indoor radon The oldest case of TENR, a major contributor to the exposure of the population Radon spas A questionable practice with TENR aspects Also: Phosphate fertilizers, well water sources

12. Nuclear tests in the atmosphere Number and total power per year Year

13. Nuclear tests in the atmosphere Annual and total deposition of Cs137, Bq m -2, Denmark..................... Nuclear tests.......................... ^ Chernobyl Year............ Total deposition Annual deposition

14. Nuclear tests in the atmosphere Evaluation of Cs137 pollution in Europe

15. Nuclear tests in the atmosphere Radioactive pollution of food, sample values, Bq/kg YearCountryProductNuclide Concentration 1957UKMilk powder 137 Cs32 1959USAMilk 137 Cs 3 1961USA Milk 137 Cs 2 1962USA Fresh milk 137 Cs 7 1963USA Milk 137 Cs 5.6 1964-65USAMilk 137 Cs 5 1985FinlandMilk 137 Cs 0.23 1957USAMilk 131 I37 1962USAFresh milk 131 I20 1885 USAMilk 131 I 1.3 1962USAFresh milk 90 Sr 1.8 1963USAMilk 90 Sr 1.0 1960ΗΠΑBeef meat 137 Cs 1.2 1985FinlandBeef meat 137 Cs 0.9 1980-85FinlandLake fish 137 Cs42 1984SpainFish 137 Cs 1 – 6 1985IrelandFish 137 Cs 8 – 35 1963-67 USA, UtahAnimal foodstuff 137 Cs 112

16. Nuslear tests in the atmosphere Radioactive pollution of food, Cs137, Bq kg -1, USA, 1993 Product Maximum Average Leafy vegetables 210 21 Other vegetables 38 3 Fruits 20 3 Potatoes 11 1.4 Pastry 23 4.3 Milk products 48 5 Fish 7.6 1.9 Eggs 1 0.4 Coffee 24 16 Tea 950 47 Aromatic species 580 29

17. Nuclear tests in the atmosphere Monthly intake of Cs137, Bq, USA, 1993 Total intake in 1993: 3300 Bq. Related dose: 42 μSv

18. Radioactive pollution of soil Relation between radioactive deposition and rainfall Rainfall, mm Radioactive deposition, kBq m -2

19. Radioactive pollution of food chain - Α Air - soil pathways of radioactive pollution Source Inhalation ( External radiation ) Direct pollution Food Air Soil Plants Animals MAN Pollution of – and from water sources

20. Radioactive pollution of food chain - Β Fresh and marine water pathways of radioactive pollution Pollution source Direct pollution Food Air Plants Fish Lakes, Sea Soil Soil pathways to man MAN FishRivers Washout, irrigation

21. Radioactive pollution of plants Various paths of pollutants propagation Radioactive deposition Propagation and fixation in soil Root uptake External pollution, foliar uptake Air clearance Washout Plant metabolism Resuspension Evaporation Base uptake Organic layer

22. Radioactive pollution of animals Various pathways Inhalation Food Meat Milk

23. Chernobyl accident - Greece Radioactive deposition of Cs137 in Europe

24. Chernobyl accident - Greece Radioactive deposition of Cs137 – NTUA and ERL data

25. Chernobyl accident - Greece Marine water pollution (surface) with Cs137 – ERL evaluation

26. Chernobyl accident - Greece Average 1st year and 50-year doses through various pathways, μSv Pathway 1st year 50 years Inhalation 22 22 External exposure 52 190 Food - water 420 500 TOTAL 490 710 The radiologically most important food chain pathways Grass pollution with Ι131 > Sheep and goat milk Grass pollution with Cs137>Sheep and goat milk and meat Pollution of fruits and vegetables Animal foodstuff pollutio >Meat and milk products, 1986/87 Cereals pollution>Bread and pastry, 1986/87

27. Chernobyl accident - Greece Evaluation of weekly doses. Comparison with dose due to natural radioactivity. Dose rate, μSv per week Chernobyl Natural radioactivity

28. Chernobyl accident - Greece Average weekly doses due to Ι131, μSv Week Contribution of various foods Meat Milk Leafy veg. Other veg. Fruits

29. Chernobyl accident - Greece Monthly doses from Cs137 and Cs134, μSv Month Contribution of various foods Meat Milk Other veg. Fruits Pastry

30. Chernobyl accident - Greece Contribution of different foods to the dose due to Cs137, Cs134 and I131 Meat Milk Leafy veg. Other veg. Fruits Pastry

31. Countermeasures: intervention levels Countermeasure Dose levels, mSvAverage dose, Low level High levelOrgan Greece Sheltering 5 50Whole body 0.02 Administration of stable iodine 50 500Thyroid 0.2 Evaquation 50 500Whole body 0.05 Relocation 50 500Whole body 0.05 Food banning 5 50Whole body 0.45 Food countermeasuresAdvices* to avoid consumption of sheep milk and leafy vegetables Applied in Greece:Control of cheese, cereals and meat and application of the EU limits Temporary banning of small animals consumption Temporary banning of specific types of bread