MODARIA II WG 4 : Working Group 4 – Transfer processes and data for radiological impact assessment
Assessing the radiological impact from radioactivity in the environment We need to adequately quantify the key transfer processes and recognise their limitations in radiological assessments • improve understanding and quantification of key processes The transfer processes and related data will vary depending on the situation considered; • planned, existing and emergency exposure situations • characteristics of the environment • terrestrial, freshwater, marine • temperate or non-temperate systems
WG 4 report status • Final draft distributed before this meeting • Prioritising radioisotopes and data gaps • K d – soils, freshwater, marine • Transfer to milk and to wild game in Japan • Final review at TM II • Peer review? • Finished!
WG4: Objectives for three sub groups • To identify key transfer processes for radioactivity in the environment, in the context of the situation under consideration, for use in radiological impact assessment and to provide analysis of key relevant data. Current Focus on K d • To consider the impact of the accidental release from the Fukushima Dai-ichi site in Japan in 2011 and the applicability of existing models and data to the Japanese situation. • To provide advice on the applicability of assessment models to tropical, semi-tropical and arid environments.
Relevance to regulatory goals of IAEA Human and environmental radiological protection in situations of regular operational activities and in accidental scenarios. WG4 is working toward: • Strengthening evaluation of the radiological impact by improving the data underpinning the models developed for assessing the transfer of RNs in the environment and the radiological impact • To more appropriately assess exposure levels of the public and in the environment - to ensure an appropriate level of protection from the effects of ionizing radiation, associated with radionuclide releases and from existing radionuclides in the environment
MODARIA II WG4 Revision and Improvement of K d Values for Terrestrial, Freshwater and Marine Systems
Review of IAEA MARiS (Marine Information System) Database • Feasibility of using MARiS database as global repository of K d data investigated. • MARiS has the potential to generate K d values. • Preliminary Investigations underway.
Preliminary Investigations in MARiS database Sample Type TRS 422 Calculated Reference K d Value K d Value Bottom 5 x 10 3 Sediment 4 x 10 3 Suspended 5 x 10 4 Matter • Baltic Sea Case Study • Generated K d values using seawater and sediment activity concentration data for Cs-137. • Difference in K d values for sediment and suspended solids. • Further investigations to begin in Nov 2017 (IRSN).
Development of global database of K d values • Harmonisation of soil, freshwater and marine data required. • Requires K d data and other relevant meta-data to be collated i.e. information on soil/sediment/seawater etc. • Prototype database developed – testing required.
Interim Meeting Monaco 31 st May – 2 nd June 2017 - Presentations
Joint work with MODARIA II WG7 • Discussions with WG7 on • How K d values are used in marine modelling. • How they are handled in equilibrium and dynamic situations. • What radionuclides and situations are of primary concern from a marine modelling point of view. • Further collaboration with WG7 utilizing experimental K d values in marine models (once data is published)
WG4 sub-group Collation of environmental transfer parameters after the Fukushima accident (Fukushima parameters) 1 st Interim meeting @ University of Tsukuba, 10-12 July, 2017
International experts As Asso sociate e exper perts River+Catchment: UK, France Marine: Australia, UK, Korea Rice+ Agricultural Crops: Italy, UK Forest: France, UK Game animals: UK, Australia Food processing: Germany Datasets: All Japanese research group leaders River+Freshwater biota: S. Hayashi (NIES) Catchments: Y. Onda (Tsukuba Univ.) Marine: H. Takata (MERI) Rice: H. Tsukada (Fukushima Univ.) Agricultural crops: T. Shinano (NARO) Forest: S. Hashimoto (FFPRI) Game animals, & Food processing: K. Tagami (QST )
Fuk Fukushima da datasets: s: a sho hort r repo eport f from the i he inter erim m mee eeting • Time series [RCs] data in marine, river, forest, and catchments and possible transfer mechanisms in these compartments presented. • Change with time in Concentration ratio (CR) or Tag for marine and freshwater fish and game animals presented. • Examples of transfer factors (TFs) of RCs in agricultural products, incl. rice, reported. Application of K fertilizer to arable land is key remediation action so info on K application and TFs would be combined in the datasets. Need to explore whether similar datasets are available from the Chernobyl accident to allow comparison. Game Forest Marine River Catchment Agricultural Rice product paddy field Food processing
CR value changes with time for four marine fish species (before and after the Fukushima Daiichi NPP accident, off Fukushima) Greenling ( アイナメ ) Japanese flounder ( ヒラメ ) 1000 10000 1000 100 100 10 10 Effective half-life: 580 days Effective half-life: 300 days 1 1 Black rockfish ( クロソイ） Conger-eel ( マアナゴ ) 10000 10000.00 1000 1000.00 100 100.00 10 10.00 Effective half-life: 360 days Effective half-life: 350 days 1 1.00 Effective half lives (2012 (peak year) and after) were obtained using exponential fitting curves
Forest data updates 4197 records from 61 journal papers and 2 reports (preliminary) (No location (latitude and longitude) Information for 781 records ) Geographical distributions Records: animal, soil and tree 1400 1200 1000 Total (N) Records 800 Animal 203 Soil 166 600 Tree 5264 400 200 0 2011 2012 2013 2014 2015 2016 Sampling year 2011-2012: Tree > Soil >> Animal 2013- : Soil > Tree >> Animal
This week - Check ecosystems/areas for which datasets will be compiled (nearly finished). - Update data for forest, marine, catchments and food processing. - Discuss radiocaesium fate in Japanese forest ecosystems incl. potential parameters to be reported, e.g. translocation in tree and transfer to mushrooms. - Discuss dataset compilation and application - Discuss table formats to be included in Tecdoc from databases.
MOD ODARI RIA I II WG4 Sub-group “Transfer Parameters in Non-temperate Systems”
Joint w work wi with h IUR
Objective TF for non-temperate and arid environment
Development of database Over 200 publications in 23 countries with arid climates collated: • newly published or available information in scientific journals • information delivered by members of the group such as S. Lukashenko PhD thesis on Kazakhstan, PhD student work from Nigeria and South Africa. • consideration of quality factors
Current dataset status Excel dataset with > 250 records Country Radionuclide Soil type Calculated TF Plant Group Transfer Factor (GM) Plant compartment GSD Soil pH TF Minimum Location TF maximum Climate Concentration in Soil (Bq/kg dw) Concentration in Plant (Bq/kg dw) Food Quality Factor (1-4) Comment Information source info
K. Kehagia (Greece) K. Eleftheriadis (Greece) Mr. Wu (China) Results of U-238/U-234 and Ra Radiation monitoring and Results of air born measurements in seawater, radioecological impact radioactivity, surface river water and resuspension and assessments of in the Tsinghua freshwater from her University in Beijing dispersion modelling monitoring studies N. Semioshkina (Germany) H. Florou (Greece) Report on consumption habits and agricultural Latest results on concentration practices in Arab countries ratios in natural biota S. Fesenko (IAEA) First results with significantly higher TFs Cs-137/Sr-90 in tropical environments, compared to tendentially lower TFs in subtropical environments
Factors affecting food consumption in arid countries 1.Socio-cultural and economics environment 2.Urban/Rural differences 3.Geographical differences 4.Religious differences 5.Others
Dietary habits of people in the Arab world
This week – order of sub topics • Briefing on interim meetings and final report review • Terrestrial, freshwater and marine K d • Fukushima data • Non-temperate systems
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