Terrestrial radionuclides An example from the U 238

Terrestrial radionuclides An example from the U 238 family Ra 226 Rn 222 Po 218 Pb 214 Bi 214 α γ α α β β γ γ

Exposure to ionizing radiation 500 000 particles of cosmic origin Our body is penetrated each hour approximately by: 30 000 α- and β-particles from the radon daughters deposited in the respiratory tract Εξωτερική έκθεση External exposure Εσωτερική έκθεση Internal exposure 200 000 γ-quanta from the terrestrial radionuclides 15 000 β-particles from the K 40 in our tissues

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)

Terrestrial radionuclides U 238 Series U 238 Th 234 Pa 234 m U 234 Th 230 Ra 226 Rn 222 Po 218 Pb 214 Bi 214 Po 214 Pb 210 Bi 210 Po 210 Typical concentrations: 20 – 200 Bq/kg Th 232 Series Th 232 Ra 228 Ac 228 Th 228 Ra 224 Rn 220 Po 216 Pb 212 Bi 212 Po 212 Typical concentrations : 20 – 200 Bq/kg U 235 Series U 235 Th 231 Pa 231 Ac 227 Th 227 Ra 223 Rn 219 Po 215 Pb 211 Bi 211 Tl 207 Typical concentrations : 1 – 10 Bq/kg K 40 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.

Concentrations of terrestrial radionuclides - Greece U 238 Series Reg. averages: 20 -60 Bq/kg Th 232 Series Reg. averages : 20 -60 Bq/kg K 40 Reg. averages : 200 -800 Bq/kg

Terrestrial radiation - Greece Regional dose rate averages, n. Gy h-1

Natural radionuclides in air U 238 Series (Rn 222 (radon) and its decay products) Rn 222 Po 218 Pb 214 Bi 214 Po 214 Typical concentrations: 30 – 200 Bq/m 3 indoors 2 – 5 Bq/m 3 outdoors Th 232 Series (Rn 220 (thoron) and its decay products) Rn 220 Po 216 Pb 212 Bi 212 Po 212 Typical concentrations : typically 10 times lower than those of Rn 222 Cosmogenic isotopes C 14, H 3, Be 7 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

Natural radionuclides in marine water Typical concentrations, Bq/m 3 U 238 K 40 - 33 11000 H 3 C 14 Rb 87 - 0. 6 5 1100 Natural radionuclides in food Typical concentrations, Bq/kg Products Banana Brasil nuts Carrots Potatoes Beer Beef Drinking water Κ 40 Ra 226 130 210 125 15 110 0 - 0. 5 0. 04 40 - 250 0. 02 - 0. 07 0. 04 - 0. 1 0. 02 0 - 0. 01

Natural radioactivity of food Total activity concentration, Bq kg-1 Product Vegetable oil Milk Alcoholic drinks Beer Drinking water Brazil nuts Bananas Tea Pastry Pistachios Total activity conc. 180 Bq kg-1 50 45 15 0. 7 500 110 15 5 4. 5

Natural radionuclides in human body Typical values, Bq Radionuclide Total activity U 238 Th 232 K 40 Ra 226 C 14 H 3 Po 210 1. 1 0. 11 4400 1. 1 15000 23 37 Average daily intake 0. 023 0. 011 100 0. 08 280 1

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

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

Nuclear tests in the atmosphere Annual and total deposition of Cs 137, Bq m-2, Denmark . . . Total deposition . . Annual deposition . Year. . . . . Nuclear tests. . . ^ Chernobyl

Nuclear tests in the atmosphere Evaluation of Cs 137 pollution in Europe

Nuclear tests in the atmosphere Radioactive pollution of food, sample values, Bq/kg Year Country Product Nuclide 1957 1959 1961 1962 1963 1964 -65 1985 UK USA USA USA Finland Milk powder Milk Fresh milk Milk 137 Cs 1957 1962 1885 USA USA Milk Fresh milk Milk 131 I 1962 1963 USA Fresh milk Milk 90 Sr 1960 1985 ΗΠΑ Finland Beef meat 137 Cs 1980 -85 1984 1985 Finland Spain Ireland Lake fish Fish 137 Cs 42 1– 6 8 – 35 1963 -67 USA, Utah Animal foodstuff 137 Cs 112 137 Cs 137 Cs 131 I 90 Sr 137 Cs Concentration 32 3 2 7 5. 6 5 0. 23 37 20 1. 3 1. 8 1. 0 1. 2 0. 9

Nuslear tests in the atmosphere Radioactive pollution of food, Cs 137, Bq kg-1, USA, 1993 Product Maximum Average Leafy vegetables Other vegetables Fruits Potatoes Pastry Milk products Fish Eggs 210 38 20 11 23 48 7. 6 1 21 3 3 1. 4 4. 3 5 1. 9 0. 4 Coffee Tea Aromatic species 24 950 580 16 47 29

Nuclear tests in the atmosphere Monthly intake of Cs 137, Bq, USA, 1993 Total intake in 1993: 3300 Bq. Related dose: 42 μSv

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

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

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

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

Radioactive pollution of animals Various pathways Meat Inhalation Milk Food

Chernobyl accident - Greece Radioactive deposition of Cs 137 in Europe

Chernobyl accident - Greece Radioactive deposition of Cs 137 – NTUA and ERL data

Chernobyl accident - Greece Marine water pollution (surface) with Cs 137 – ERL evaluation

Chernobyl accident - Greece Average 1 st year and 50 -year doses through various pathways, μSv Pathway 1 st year 50 years Inhalation External exposure Food - water 22 52 420 22 190 500 TOTAL 490 710 The radiologically most important food chain pathways Grass pollution with Ι 131 Grass pollution with Cs 137 Pollution of fruits and vegetables > > Sheep and goat milk and meat Animal foodstuff pollutio Cereals pollution > > Meat and milk products, 1986/87 Bread and pastry, 1986/87

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

Chernobyl accident - Greece Average weekly doses due to Ι 131, μSv Week Contribution of various foods Meat Milk Leafy veg. Other veg. Fruits

Chernobyl accident - Greece Monthly doses from Cs 137 and Cs 134, μSv Month Contribution of various foods Meat Milk Other veg. Fruits Pastry

Chernobyl accident - Greece Contribution of different foods to the dose due to Cs 137, Cs 134 and I 131 Meat Milk Leafy veg. Other veg. Fruits Pastry

Countermeasures: intervention levels Countermeasure Sheltering Dose levels, m. Sv Low level High level 5 50 Administration of stable iodine 50 Evaquation Relocation Food banning Food countermeasures Applied in Greece: Organ Average dose, Greece Whole body 0. 02 500 Thyroid 0. 2 50 500 Whole body 0. 05 5 50 Whole body 0. 45 Advices* to avoid consumption of sheep milk and leafy vegetables 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