ra226 rn222 po218 pb214 bi214 terrestrial radionuclides an example from the u238 family α α α β...
TRANSCRIPT
Ra226
Rn222
Po218
Pb214
Bi214
Terrestrial radionuclidesAn example from the U238 family
α
α
α
β
β
γ
γ
γ
Exposure to ionizing radiation
Εξωτερική έκθεση
Εσωτερική έκθεση
Our body is penetrated each hourapproximately by:
30 000 α- and β-particles from theradon daughters deposited in therespiratory tract
15 000 000 β-particles from the K40 in our tissues
200 000 000 γ-quantafrom the terrestrial radionuclides
500 000 particles ofcosmic origin
Internal exposure
External exposure
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
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
50V, 87Rb, 113Cd, 115In, 123Te, 138La, 142Ce, 144Nd, 147Sm, 152Gd, 174Hf, 176Lu, 187Re, 190Pt, 192Pt, 209Bi.
Typical concentrations : very low, radiologically insignificant.
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
Terrestrial radiation - GreeceRegional dose rate averages, nGy h-1
Natural radionuclides in air
U238 Series (Rn222 (radon) and its decay products)
Rn222 Po218 Pb214 Bi214 Po214
Typical concentrations: 30 – 200 Bq/m3 indoors
2 – 5 Bq/m3 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, Be710Be, 26Al, 36Cl, 80Kr, 32Si, 39Ar, 22Na, 35S, 37Ar, 33P, 32P, 38Mg, 24Na, 38S, 31Si, 18F, 39Cl, 38Cl
Natural radionuclides in marine waterTypical concentrations, Bq/m3
U238 - 33 H3 - 0.6
K40 - 11000 C14 - 5
Rb87 - 1100
Natural radionuclides in foodTypical concentrations, Bq/kg
Products Κ40 Ra226
Banana 130 0.04
Brasil nuts 210 40 - 250
Carrots 125 0.02 - 0.07
Potatoes 125 0.04 - 0.1
Beer 15 -
Beef 110 0.02
Drinking water 0 - 0.5 0 - 0.01
Natural radioactivity of foodTotal activity concentration, Bq kg-1
Product Total
activity conc.
Vegetable oil 180 Bq kg-1
Milk 50
Alcoholic drinks 45
Beer 15
Drinking water 0.7
Brazil nuts 500
Bananas 110
Tea 15
Pastry 5
Pistachios 4.5
Natural radionuclides in human bodyTypical 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
Technologically enhanced natural radioactivity (TENR)Radiologically important cases
Uranium mining and millingEnhanced concentrations of U-series nuclides in areas of waste deposition
Lignite power plantsAir and soil pollution with lignite ash of enhanced natural radioactivity
Building materialsUse of lignite ash as cement component, phosphate byproducts, granites
Indoor radonThe oldest case of TENR, a major contributor to the exposure of the population
Radon spasA questionable practice with TENR aspects
Also: Phosphate fertilizers, well water sources
0
10
20
30
40
50
60
70
40 45 50 55 60 65 70 75 80
Ετος
No
/ M
T
Nuclear tests in the atmosphereNumber and total power per year
Year
0
500
1000
1500
2000
2500
3000
3500
4000
1950 1955 1960 1965 1970 1975 1980 1985 1990
Ετος
Ετή
σια
/ σ
υνο
λικ
ή ε
ναπ
όθε
ση
Cs1
37,
Bq
/m2
Nuclear tests in the atmosphereAnnual and total deposition of Cs137, Bq m-2, Denmark
..................... Nuclear tests .......................... ^ Chernobyl
Year
.
.
.
.
.
.
Total deposition
Annual deposition
Nuclear tests in the atmosphereEvaluation of Cs137 pollution in Europe
Nuclear tests in the atmosphereRadioactive pollution of food, sample values, Bq/kg
Year Country Product Nuclide Concentration
1957 UK Milk powder 137Cs 321959 USA Milk 137Cs 31961 USA Milk 137Cs 21962 USA Fresh milk 137Cs 71963 USA Milk 137Cs 5.61964-65 USA Milk 137Cs 51985 Finland Milk 137Cs 0.23 1957 USA Milk 131I 371962 USA Fresh milk 131I 201885 USA Milk 131I 1.3
1962 USA Fresh milk 90Sr 1.81963 USA Milk 90Sr 1.0
1960 ΗΠΑ Beef meat 137Cs 1.21985 Finland Beef meat 137Cs 0.9
1980-85 Finland Lake fish 137Cs 421984 Spain Fish 137Cs 1 – 61985 Ireland Fish 137Cs 8 – 35
1963-67 USA, Utah Animal foodstuff 137Cs 112
Nuslear tests in the atmosphereRadioactive pollution of food, Cs137, Bq kg-1, USA, 1993
Product Maximum Average
Leafy vegetables 210 21Other vegetables 38 3Fruits 20 3Potatoes 11 1.4Pastry 23 4.3Milk products 48 5Fish 7.6 1.9Eggs 1 0.4
Coffee 24 16Tea 950 47Aromatic species 580 29
Nuclear tests in the atmosphereMonthly intake of Cs137, Bq, USA, 1993
0
100
200
300
400
500
600
Dec-62 Mar-63 Jul-63 Oct-63 Jan-64 May-64 Aug-64
Inta
ke o
f C
s137
, B
q/m
on
th
Total intake in 1993: 3300 Bq. Related dose: 42 μSv
Radioactive pollution of soilRelation between radioactive deposition and rainfall
0.1
1
10
100
1000
0 5 10 15 20 25 30
Βροχόπτωση, mm
Ρα
διε
νερ
γό
ς εν
απ
όθε
ση
, kb
q/m
2 Cs137
Zr95
Rainfall, mm
R
ad
ioa
cti
ve
de
po
sit
ion
, k
Bq
m-2
Radioactive pollution of food chain - ΑAir - soil pathways of radioactive pollution
Source
Inhalation
( External radiation )
Direct pollution
FoodAir Soil
Plants
Animals
MAN
Pollution of – and from water sources
Radioactive pollution of food chain - ΒFresh and marine water pathways of radioactive pollution
Pollutionsource
Direct pollution
FoodAir
Plants
Fish
Lakes,
Sea
SoilSoil pathways to man
MAN
FishRivers
Washout, irrigation
Radioactive pollution of plantsVarious paths of pollutants propagation
Radioactive deposition
Propagation and fixation in soil
Root uptake
External pollution, foliar uptake
Air clearance
Washout
Plant metabolism
Resuspension
Evaporation
Evaporation
Base uptake
Organic layer
Radioactive pollution of animalsVarious pathways
Inhalation
Food
Meat
Milk
Chernobyl accident - GreeceRadioactive deposition of Cs137 in Europe
Chernobyl accident - GreeceRadioactive deposition of Cs137 – NTUA and ERL data
Chernobyl accident - Greece Marine water pollution (surface) with Cs137 – ERL evaluation
Chernobyl accident - Greece Average 1st year and 50-year doses through various pathways, μSv
Pathway 1st year 50 years
Inhalation 22 22External exposure 52 190Food - water 420 500
TOTAL 490 710
The radiologically most important food chain pathways
Grass pollution with Ι131 > Sheep and goat milkGrass pollution with Cs137 > Sheep and goat milk and meatPollution of fruits and vegetables
Animal foodstuff pollutio > Meat and milk products, 1986/87Cereals pollution > 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 Ι131, μSv
0.1
1
10
100
1 2 3 4 5 6 7 8
Εβδομάδα
Εβ
δο
μα
δια
ία δ
όσ
η I1
31
, μS
v
Κατανομή δόσεων από I131
10%
22%
42%
15%
11%Κρέας
Γάλα
Λαχαν. Φυλ.
Λαχαν. Αλλα
Φρούτα
Week Contribution of various foods
MeatMilkLeafy veg.Other veg.Fruits
Chernobyl accident - Greece Monthly doses from Cs137 and Cs134, μSv
1
10
100
1 3 5 7 9 11
Μήνας
Μη
νια
ίες
δό
σει
ς λ
όγ
ω κ
αισ
ίου
Κατανομή δόσεων από Cs137 και Cs134
15%
15%
0%
2%23%
45%
Κρέας
Γάλα
Λαχαν. Αλλα
Φρούτα
Ζυμαρικά
Month Contribution of various foods
MeatMilkOther veg.FruitsPastry
Chernobyl accident - Greece
Κατανομή δόσεων από I131, Cs137 και Cs134 στα τρόφιμα
14%
17%
9%5%20%
35%Κρέας
Γάλα
Λαχαν. Φυλ.
Λαχαν. Αλλα
Φρούτα
Ζυμαρικά
Contribution of different foods to the dose due to Cs137, Cs134 and I131
Meat
Milk
Leafy veg.
Other veg.
Fruits
Pastry
Countermeasures: intervention levels
Countermeasure Dose levels, mSv Average dose,
Low level High level Organ Greece
Sheltering 5 50 Whole body 0.02
Administration
of stable iodine 50 500 Thyroid 0.2
Evaquation 50 500 Whole body 0.05
Relocation 50 500 Whole body 0.05
Food banning 5 50 Whole body 0.45
Food countermeasures Advices* 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