EcoDoses - Improving radiological assessment of doses to man from terrestrial ecosystems. A status report for the NKS-B project 2005

• Main Authors: Nielsen, S.P., Andersson, Kasper Grann, Thørring, H., Bergan, T.D., Liland, A., Joensen, H.P., Almgren, S., Nilsson, E., Isaksson, M., Erlandsson, B., Saxén, R., Kostiainen, E., Palsson, S.E.
• Format: Book
• Language: English
• Published: Nordic Nuclear Safety Research 2006
• Subjects: Kompetenceplatforme og videndeling; Nuclear weapons fallout; Deposition modelling; Food-chain modelling; Ecological half-lives; Radioecological sensitivity; /dk/atira/pure/sustainabledevelopmentgoals/life_on_land; SDG 15 - Life on Land; Arctic
• Online Access: https://orbit.dtu.dk/en/publications/aa2ca497-c959-4f29-90c9-97d2410d2a31; https://backend.orbit.dtu.dk/ws/files/7712223/nks_123.pdf

Considerable variations in activity concentrations in milk of 137 Cs and 90 Sr were observed between countries or regions due to precipitation patterns, soil types and inhomogeneity of Chernobyl fallout. Time trends indicate that factors influencing ecological half-lives for 90 Sr are not the same as for 137 Cs in the pasture–milk system. Internal doses to Faroese people derive mainly from dairy products, lamb and potatoes. The largest doses were received from nuclear weapons fallout in the early 1960’s. 137 Cs causes higher doses than 90 Sr, and the regional variability is larger for 137 Cs than for 90 Sr. 137 Cs deposition maps were made of Sweden. Values of 137 Cs deposition and precipitation were used in the calculations of Nuclear Weapons Fallout (NWF). The deposition of 137 Cs from the Chernobyl accident was calculated for western Sweden. Lowest levels of NWF 137 Cs deposition density were noted in the north-eastern and eastern Sweden and the highest levels in the western parts. The Chernobyl 137 Cs deposition is highest along the coast and lowest in the south-eastern part and along the middle. The calculated deposition from NWF and Chernobyl in western Sweden was compared to observed deposition and showed good agreement. Ecological halftimes of 137 Cs in perch in Finnish lakes vary by a factor of three. The longest halftime of 137 Cs in perch was 9 y and the shortest 3 y. Norwegian lakes differ from each other with respect to the rates of decrease of 137 Cs in fish. Ecological halftimes of 137 Cs in trout and Arctic char varied from 1 to 5 y. A more rapid reduction of 137 Cs in fish is found in certain Norwegian lakes compared to Finnish lakes. In two Norwegian lakes the 137 Cs concentrations in trout remain at about 100 Bq/kg since 1990. The European decision support systems, ARGOS and RODOS, include foodchain modules with default parameters derived from southern Germany. Many parameters describing foodchain transfer are subject to considerable variation according to local conditions. Such parameters ...