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222 Rn in air. Transfer analysis of 210 Po and 210 Pb in the terrestrial environment. 210 Pb 210 Po. 210 Pb 210 Po. Bertil R.R. Persson PhD. MDhc Professor em . of medical radiation physics Lund University. SE-22185 Lund. Sweden. 238 U. Deposition of 210 Pb 210 Po. 222 Rn
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222Rn in air Transfer analysis of 210Po and 210Pb in the terrestrial environment 210Pb 210Po 210Pb 210Po Bertil R.R. Persson PhD. MDhc Professor em. of medical radiation physics Lund University. SE-22185 Lund. Sweden 238U
Deposition of 210Pb 210Po 222Rn in air Other release 210Pb 210Bi 210Po 218Po 214Pb 214Bi 214Po 1 222Rn 226Ra 230Th 234U 234Pa 234Th 238U Vegetation Plants, Lichen, moss Soil / Water 3 2 Animals Cow, reindeeretc 4 5 Inhalation Food intake: vegetablesmilk, meat 6 Human Exposure
Atmospheric Deposition of 210Pb and 210Po 1
210Pb Total atmospheric deposition /Bq.m-2.a-1 210Pb 140 60 Bq.m-2.a-1 210Pb 60 30 Bq.m-2.a-1
210Po Total atmospheric deposition /Bq.m-2.a-1 210Po 70 40 Bq.m-2.a-1 210Po 17 3 Bq.m-2.a-1
2 Atmospheric Deposition AD 210Pb 14060 Bq.m-2.a-1 210Po 70 40 Bq.m-2.a-1 Deposition Transfer factor ”DTF” APDS Activity-concentration in plant grown in open field (Bq.kg-1 dry weight) APS Activity-oncentration in plant grown in shelter (Bq.kg-1 dry weight) Soil Transfer factor ”STF” Activity-concentration in Soil AS
Deposition Transfer factor ”DTF” • DTF = Difference of the activity concentration A in plants grown in open field “APDeposition+Soil” and in tent shelter (“APSoil”) • __________________________________________________ • divided by the atmospheric deposition “AD” during the vegetation period (Bq.m-2).
Fractional Uptake from Deposition: DTF100 % Pietrzakflis, Z. and M. Skowronskasmolak (1995). "Transfer of Pb-210 and Po-210 to plants via root-system and above ground interception." Science of the Total Environment 162(2-3): 139-147.
The fraction of 210Pb firmly incorporated into the plant is about: 82±20 % for atmospheric deposited 210Pb and 60±20 % for 210Pb taken up from soil. Pietrzakflis, Z. and M. Skowronskasmolak (1995). "Transfer of Pb-210 and Po-210 to plants via root-system and above ground interception." Science of the Total Environment 162(2-3): 139-147.
210Pb and 210Po in soil 3
Deposition of 210Pb and 210Po Un-supported 210Pb and 210Po in soil Supported Ingrowth of 210Pb and 210Po from radioactivedecay of 238U in the ground
Soil average activity concentration 60 ± 13 Bq.kg-1
The distribution of activity concentrations of 210Pb and 210Po in 28 samples of phosphatefertilizers in Italy {Roselli, 2009 } . Soil average activity concentration 60 ± 13 Bq.kg-1
Distribution and enrichment of 210Po in soil of Kaiga in South India Data from [N. Karunakara et al. / J. Environ. Radioactivity 51 (2000) 349}362].
Undisturbed flat referencesite CultivatedSoil Benmansour, M., L. Mabit, et al. (2013). "Assessment of soil erosion and deposition rates in a Moroccan agricultural field using fallout Cs-137 and Pb-210(ex)." Journal of Environmental Radioactivity 115: 97-106.
4 210Pb in food chain grass-cattle-milk Atmospheric Deposition 210Pb 14060 Bq.m-2.a-1 210Po 70 40 Bq.m-2.a-1 t 5-10% 210Pb Fodder Ca: 1-10 Bq.kg-1 d.w. Soil 85-90% Intake: 16 kg dwfodder /day = 16-160 Bq.d-1 210Pb Transfer coefficient IAEA: 0.00033 d.kg-1 fresh w. This w: 0.0056 d.kg-1 fresh w. 210Pb Milk Ca: 30-45 mBq.kg-1
4 210Pb and 210Po in milk A few studies have been performed to quantitatively study the transfer of the natural radionuclides 210Pb and 210Po from fodder to milk: Amaral, E. C. S., et al. (1988). "Transfer of Ra-226 and Pb-210 to forage and milk in a Brazilian high natural radioactivity region." Radiation Protection Dosimetry 24(1-4): 119-121. Staples, C. R., et al. (1994). " Radionuclides in milk of dairy heifers raised on forages harvested from phosphatic clay soils on reclaimed mined land." Journal of Environmental Quality 23(4): 663-667. Strok, M. and B. Smodis (2012). "Transfer of natural radionuclides from hay and silage to cow's milk in the vicinity of a former uranium mine." Journal of Environmental Radioactivity 110: 64-68.
4 210Po in food chain grass-cattle-milk Atmospheric Deposition 210Pb 14060 Bq.m-2.a-1 210Po 70 40 Bq.m-2.a-1 t 20-30% 210Po Fodder Ca: 1-10 Bq.kg-1 d.w. Soil 70-80% Intake: 16 kg dwfodder /day = 16-160 Bq.d-1 210Po Transfer coefficient IAEA: 0.00023 d.kg-1 fresh w. This w: 0.0018 d.kg-1 fresh w. 210Po Milk Ca: 40-70 mBq.kg-1
210Po and 210Pb in food chain fodder-cattle-milk The transfer coefficient Fm describes the fraction of the daily intake of radionuclides that is secreted per liter of milk. The daily radionuclide intake = Activity concentration of fodder (Bq.kg-1) Daily Intake of fodder (kg.d-1).
Activity Concentration ratios (Bq/kg d.m.)/( Bq/kg d.m.) between milk and different kinds of fodder Staples, C. R., et al. (1994). Journal of Environmental Quality 23(4): 663-667.
4 210Pb and 210Po in meat A few studies have been performed to quantitatively study the transfer of the natural radionuclides 210Pb and 210Po from fodder to meat: Howard, B. J., N. A. Beresford, et al. (2009). "Radionuclide transfer to animal products: revised recommended transfer coefficient values." Journal of Environmental Radioactivity 100(3): 263-273. Howard, B. J., N. A. Beresford, et al. (2009). "Quantifying the transfer of radionuclides to food products from domestic farm animals." Journal of Environmental Radioactivity 100(9): 767-773.
4 210Po in food chain grass-cattle-meat and beef Atmospheric Deposition 210Pb 14060 Bq.m-2.a-1 210Po 70 40 Bq.m-2.a-1 t 20-30% 210Po Fodder Ca: 1-10 Bq.kg-1 d.w. Soil 70-80% Intake: 16 kg dwfodder /day = 16-160 Bq.d-1 210Po Transfer coefficient This w: 0.001 d.kg-1 fresh w. 210Po Meat Ca: 70 mBq.kg-1
Activity concentrations of 210Pb and 210Po in meat products Bq.kg-1 fresh weight Milk 1000 Chicken 3000 Giri et. al 2012 Egg 600
The transfer of 210Pb and 210Pb from fodder to meat can be estimated by the activity concentration ratio (ACR) which is the equilibrium ratio between the radionuclide activity concentration in the fresh animal food product (Bq.kg-1 fresh weight) divided by the dry mass radionuclide activity concentration in the feedstuff ingested (Bq.kg-1 dm) {Howard. 2009 #615}.
The transfer coefficient Fmeatdescribes the fraction of the daily intake of radionuclides that is accumulated in meat. The daily radionuclide intake = Activity concentration of fodder (Bq.kg-1) Daily Intake of fodder (kg.d-1).
5 210Po and 210Pb in artic food chains Lichen-reindeer meat Lichen-Caribou meat
210Po and 210Pb in the food chain lichen-reindeer and man Lichen - reindeer - man 210Pb 240 Bq/kg d.w. 0,030 Bq/kg w.w. 0.070 Bq / kg w.w. 210Po 200 7 0.5
By assuming zero recycling contribution from soil in the top layer to the lichen plant the effective rate-constant for changing of the radioactivity concentration by first order kinetics is 2.1 a-1 and in the deepest soil layer the the effective rate-constant for changing of the radioactivity concentration by first order kinetics is 0.03 a.
5 Annual Deposition 210Po 22 Bq.m-2.a-1 Polonium-210 Reindeer t 210Po Lichen Ca: 242 Bq.kg-1 Intake: 290 Bq.d-1 Transfer coefficient 0.031 d.kg-1 fresh w. Reindeermeat Ca: 6-8 Bq.kg-1 210Po
210Pb and 210Po activity concentrations in reindeer meet samples collected in various countries. The average activity concentration of 210Pb is 0.6 ±0.2 Bq.kg-1 and for 210Po 6.8 ±1.0 Bq.kg-1
5 Annual Deposition 210Po 22 Bq.m-2.a-1 Polonium-210 Caribou t 210Po Lichen Ca: 242 Bq.kg-1 Intake: 290 Bq.d-1 Transfer coefficient 0.035 d.kg-1 fresh w. Cariboumeat Ca: 7-11 Bq.kg-1 210Po
210Pb and 210Po activity concentrations in caribou meet samples collected in various countries. The average activity concentration of 210Pb is 1.6 ±0.5 Bq.kg-1 and for 210Po 8.8 ±1.5 Bq.kg-1
210Pb and 210Po activity concentrations in reindeer and caribou meet samples collected in various countries. In reindeer meat the average activity concentration of 210Pb is 0.6 ±0.2 Bq.kg-1 and for 210Po 6.8 ±1.0 Bq.kg-1 In caribou meat the average activity concentration of 210Pb is 1.6 ±0.5 Bq.kg-1 and for 210Po 8.8 ±1.5 Bq.kg-1
210Po and 210Pb in man 6 man 210Pb 0.070 Bq / kg w.w. 210 0.5 Bq / kg w.w
Deposition 670 l.m-2.a-1 210Pb 104 Bq.m-2 Lead-210 210Pb Fractional Residence time: Pb = 0.01d Pb =0.02 d Pb =1.6 d 210Pb Reindeer meat intake 0. 2-0. 5 kg.d-1 Fractional Residence time: Pb = 1.5 d Pb =1.2 d 210Pb
Deposition 670 l.m-2.a-1 210Po 22 Bq.m-2 Polonium-210 210Po Fractional Residence time: Pb = 0.12 d Pb =0.4 d Pb =1.1 d 210Po Reindeer meat intake 0. 2-0. 5 kg.d-1 Fractional Residence time: Pb = 0.3 d Pb =0.2 d 210Po
Transfer analysis of 210Po and 210Pb in the terrestrial environment Interesting and challengingsubject to study There are still maysubjects to be studied i detailsuch as:
The End Thank you for Your attention