Radioecological Studies in Nordic Countries after the Chernobyl Accident Sven P. Nielsen Radiation Research Division

22/03/2011SFREK, Stockholm2Risø DTU, Technical University of Denmark Chernobyl Accident, Saturday 26 April 1986 Radioactive fallout in Denmark first recognised at Risø on the morning of Monday 28 April from gamma spectrometric analysis of routine grass sample showing fresh fission products Contact to colleagues confirmed similar findings in Sweden Meteorological data indicated origin east of Scandinavia Countrywide monitoring initiated in Denmark to obtain overview, inform authorities and public Arrival on 27 April of airborne radioactivity at Risø detected by outdoor ionization chamber logging readings over weekend (TMI inspired project with Japanese colleague)

Ionization Chamber outdoor at Risø

22/03/2011SFREK, Stockholm4Risø DTU, Technical University of Denmark Chernobyl Fallout in Denmark 131 I in air (mBq m -3 ) Fallout by September 1986

22/03/2011SFREK, Stockholm5Risø DTU, Technical University of Denmark Tjernobyl Fallout in Europe, 137 Cs

22/03/2011SFREK, Stockholm6Risø DTU, Technical University of Denmark Radioactivity in air (Risø, Haderslev og Allinge)

22/03/2011SFREK, Stockholm7Risø DTU, Technical University of Denmark 90 Sr and 137 Cs in milk

22/03/2011SFREK, Stockholm8Risø DTU, Technical University of Denmark Cesium-137 in cereals

22/03/2011SFREK, Stockholm9Risø DTU, Technical University of Denmark 90 Sr and 137 Cs in apples

22/03/2011SFREK, Stockholm10Risø DTU, Technical University of Denmark Cesium-137 in Danish food and Danes

22/03/2011SFREK, Stockholm11Risø DTU, Technical University of Denmark Chernobyl Fallout in Nordic Countries Total direct input of Cs-137 to the Baltic Sea estimated at 4.7 PBq Activity ratio of Sr-90/Cs-137 in fallout about 2%

22/03/2011SFREK, Stockholm12Risø DTU, Technical University of Denmark

22/03/2011SFREK, Stockholm13Risø DTU, Technical University of Denmark Biannual seawater sampling

22/03/2011SFREK, Stockholm14Risø DTU, Technical University of Denmark 90 Sr in seawater around Zealand

22/03/2011SFREK, Stockholm15Risø DTU, Technical University of Denmark 137 Cs in seawater around Zealand

22/03/2011SFREK, Stockholm16Risø DTU, Technical University of Denmark Radioactive isotopes vs. salinity in Danish waters 2007

22/03/2011SFREK, Stockholm17Risø DTU, Technical University of Denmark Time series of 90 Sr and 137 Cs in Danish waters vs. salinity 90 Sr 137 Cs

22/03/2011SFREK, Stockholm18Risø DTU, Technical University of Denmark Plutonium and neptunium in Danish waters vs. salinity

22/03/2011SFREK, Stockholm19Risø DTU, Technical University of Denmark 129 I in Danish waters vs. salinity

22/03/2011SFREK, Stockholm20Risø DTU, Technical University of Denmark Cesium-137 in cod

22/03/2011SFREK, Stockholm21Risø DTU, Technical University of Denmark EC Marina Balt Project EC Marina Balt Project on an assessment of the radiological exposure of man from radioactivity in the Baltic Sea Two previous EC Marina Projects –North European Waters (Marina, 1990) –Mediterranean Sea (Marina-Med, 1994) Expansion of EU in 1995 (Finland, Sweden and Austria) Marina Balt Project starts in 1996 with participants from countries around the Baltic Sea: Sweden, Finland, Russia, Poland, Estonia, Latvia, Lithuania, Germany, Denmark

22/03/2011SFREK, Stockholm22Risø DTU, Technical University of Denmark Assessment Compartment model used to predict radionuclide concentrations in seawater and biota Sources considered –Nuclear weapons fallout –Chernobyl fallout –Discharges from nuclear facilities

22/03/2011SFREK, Stockholm23Risø DTU, Technical University of Denmark Cs-137 in Baltic seawater Observed data from MORS HELCOM data base and other sources

22/03/2011SFREK, Stockholm24Risø DTU, Technical University of Denmark Doses to Critical Groups in Kattegat Region

22/03/2011SFREK, Stockholm25Risø DTU, Technical University of Denmark Doses to Critical Groups in the West Baltic

22/03/2011SFREK, Stockholm26Risø DTU, Technical University of Denmark Doses to Critical Groups in Kattegat from NPP

22/03/2011SFREK, Stockholm27Risø DTU, Technical University of Denmark Doses to Critical Groups in the West Baltic from NPP

22/03/2011SFREK, Stockholm28Risø DTU, Technical University of Denmark Maximum Doses to Critical Groups in the Baltic

22/03/2011SFREK, Stockholm29Risø DTU, Technical University of Denmark Collective Dose by Source

22/03/2011SFREK, Stockholm30Risø DTU, Technical University of Denmark Collective Dose by Country

22/03/2011SFREK, Stockholm31Risø DTU, Technical University of Denmark Collective Dose by Exposure Pathway

22/03/2011SFREK, Stockholm32Risø DTU, Technical University of Denmark Collective Dose by Radionuclide

22/03/2011SFREK, Stockholm33Risø DTU, Technical University of Denmark Collective Dose from NPP

22/03/2011SFREK, Stockholm34Risø DTU, Technical University of Denmark NKS-B PARDNOR Project Objectives: To address the need for recent and site-specific data to be used in the underlying ECOSYS radioecology model of the ARGOS and RODOS decision support systems Examples: Typical diets in the Nordic countries. ’Default’ dietary information supplied with models like ECOSYS is often used uncritically, despite of warnings that it reflects location-specific conditions. Import fractions of food products. In a Nordic emergency situation it is important to know if food consumed is produced in the Nordic countries or imported from other areas. Animal feeding regimes. These differ from country to country and could significantly affect doses.

22/03/2011SFREK, Stockholm35Risø DTU, Technical University of Denmark Swedish ARGOS implementation

22/03/2011SFREK, Stockholm36Risø DTU, Technical University of Denmark Consumption of wheat and rye Comment: practically all Norwegian and Finnish wheat is spring wheat, whereas a very large fraction of the Danish and German wheat is winter wheat.

22/03/2011SFREK, Stockholm37Risø DTU, Technical University of Denmark Consumption of potatoes, leafy vegetables and root vegetables

22/03/2011SFREK, Stockholm38Risø DTU, Technical University of Denmark Consumption of beef and milk

22/03/2011SFREK, Stockholm39Risø DTU, Technical University of Denmark Consumption of beer and milk

22/03/2011SFREK, Stockholm40Risø DTU, Technical University of Denmark Consumption of brown and other cheese in Norway Brown cheese is made from goat’s milk whey, which is not included in ECOSYS. Transfer coefficients are needed.

22/03/2011SFREK, Stockholm41Risø DTU, Technical University of Denmark Gender differences between Danish adults

22/03/2011SFREK, Stockholm42Risø DTU, Technical University of Denmark Nordic foodstuffs not included in ECOSYS diet table In Faroe Islands, whale meat and blubber (not considered in ECOSYS) constitute significant parts of the diet. Available Faroese data is old and uncertain.

22/03/2011SFREK, Stockholm43Risø DTU, Technical University of Denmark Impact on dose of using site-specific dietary information

22/03/2011SFREK, Stockholm44Risø DTU, Technical University of Denmark Percentage of foodstuffs produced within each country FoodNDKFIIS Wheat676050~0 Rye408615~0 Potatoes Leafy vegetables 55 ¤ 75 * 77 # 33 £ Berries610 ¤ 69~0 Milk n Butter986997n Cheese936366n Beef95 ¤ 8886n Pork95 ¤ 9491n Lamb95 ¤ 2030n * Figure only valid for early June to mid-October; It is 0 the rest of the year. ¤ Assumed values # Import of leafy vegetables is in Finland low in mid-June to September. £ For Iceland, only the fraction for total vegetables has been identified.

22/03/2011SFREK, Stockholm45Risø DTU, Technical University of Denmark Animal specific feeding rations Differences between German and Danish data Example of ECOSYS run ( 137 Cs dry deposition on 1 st May)

22/03/2011SFREK, Stockholm46Risø DTU, Technical University of Denmark PARDNOR Conclusions Data on Nordic diets has been compiled for application in foodchain dose models different age groups: children (1-4 y); teenagers (<15 y); adults (ca. 30 y); senior adults (ca. 60 y) Considerable differences are found between Nordic diets, which can mean significant differences in dose for the same accident situation in different countries Very different fractions of important dietary components are produced locally in the different Nordic countries Differences in animal feeding regimes have been demonstrated to be important, depending on season Significant differences in crop development by season between Nordic countries Room for model improvement on important aspects (deposition on crops, soil and snow, weathering, leaching, fixation, soil types, transfer to milk and meat)