title: Regional long-term model of radioactivity dispersion and fate in the Northwestern Pacific and adjacent seas: application to the Fukushima Dai-ichi accident.
abstract: The compartment model POSEIDON-R was modified and applied to the Northwestern Pacific and adjacent seas to simulate the transport and fate of radioactivity in the period 1945-2010, and to perform a radiological assessment on the releases of radioactivity due to the Fukushima Dai-ichi accident for the period 2011-2040. The model predicts the dispersion of radioactivity in the water column and in sediments, the transfer of radionuclides throughout the marine food web, and subsequent doses to humans due to the consumption of marine products. A generic predictive dynamic food-chain model is used instead of the biological concentration factor (BCF) approach. The radionuclide uptake model for fish has as a central feature the accumulation of radionuclides in the target tissue. The three layer structure of the water column makes it possible to describe the vertical structure of radioactivity in deep waters. In total 175 compartments cover the Northwestern Pacific, the East China and Yellow Seas and the East/Japan Sea. The model was validated from (137)Cs data for the period 1945-2010. Calculated concentrations of (137)Cs in water, bottom sediments and marine organisms in the coastal compartment, before and after the accident, are in close agreement with measurements from the Japanese agencies. The agreement for water is achieved when an additional continuous flux of 3.6 TBq y(-1) is used for underground leakage of contaminated water from the Fukushima Dai-ichi NPP, during the three years following the accident. The dynamic food web model predicts that due to the delay of the transfer throughout the food web, the concentration of (137)Cs for piscivorous fishes returns to background level only in 2016. For the year 2011, the calculated individual dose rate for Fukushima Prefecture due to consumption of fishery products is 3.6 μSv y(-1). Following the Fukushima Dai-ichi accident the collective dose due to ingestion of marine products for Japan increased in 2011 by a factor of 6 in comparison with 2010.
authors.affiliation: Institute of Mathematical Machine and System Problems, Glushkov av., 42, Kiev 03187, Ukraine. Electronic address: vladmad@gmail.com.
authors.forename: V
authors.initials: V
authors.lastname: Maderich
authors.affiliation: Ukrainian Center of Water and Environmental Projects, Glushkov av., 42, Kiev 03187, Ukraine. Electronic address: romanbezhenar@gmail.com.
authors.forename: R
authors.initials: R
authors.lastname: Bezhenar
authors.affiliation: NRG, Utrechtseweg 310, 6800 ES Arnhem, The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: Heling
authors.affiliation: NRG, Utrechtseweg 310, 6800 ES Arnhem, The Netherlands. Electronic address: g.dewith@nrg.eu.
authors.forename: G
authors.initials: G
authors.lastname: de With
authors.affiliation: Korea Institute of Ocean Science and Technology, 787, Haean-ro, Ansan 426-744, Republic of Korea. Electronic address: ktjung@kiost.ac.
authors.forename: K T
authors.initials: KT
authors.lastname: Jung
authors.affiliation: Korea Institute of Ocean Science and Technology, 787, Haean-ro, Ansan 426-744, Republic of Korea.
authors.forename: J G
authors.initials: JG
authors.lastname: Myoung
authors.affiliation: School of Earth and Environmental Sciences, Research Institute of Oceanography, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-741, Republic of Korea. Electronic address: choyk@snu.ac.kr.
authors.forename: Y-K
authors.initials: YK
authors.lastname: Cho
authors.affiliation: First Institute of Oceanography, 6 Xianxialing Road, Qingdao 266061, China. Electronic address: qiaofl@fio.org.cn.
authors.forename: F
authors.initials: F
authors.lastname: Qiao
authors.affiliation: Swedish Meteorological and Hydrological Institute, SE-601 76, Norrköping, Sweden. Electronic address: lennart.robertson@smhi.se.
authors.forename: L
authors.initials: L
authors.lastname: Robertson
mesh_terms: D000818:Animals; D002588:Cesium Radioisotopes / Q000032:analysis*; D003445:Crustacea; D005399:Fishes; D020387:Food Chain; D005506:Food Contamination; D062406:Fukushima Nuclear Accident; D019015:Geologic Sediments / Q000032:analysis; D006801:Humans; D007564:Japan; D008962:Models, Theoretical; D008974:Mollusca; D009792:Oceans and Seas; D010839:Phytoplankton; D011829:Radiation Dosage; D011834:Radiation Monitoring; D011851:Radioactivity; D015203:Reproducibility of Results; D014875:Water Pollutants, Radioactive / Q000032:analysis*; D015048:Zooplankton
chemical_list: D002588:Cesium Radioisotopes; D014875:Water Pollutants, Radioactive
keywords: Compartment modelling; Fukushima Dai-ichi accident; Human ingestion doses; Radionuclide transfer in marine biota