title: Retrospective dosimetry of Iodine-131 exposures using Iodine-129 and Caesium-137 inventories in soils--A critical evaluation of the consequences of the Chernobyl accident in parts of Northern Ukraine.
abstract: The radiation exposure of thyroid glands due to (131)I as a consequence of the Chernobyl accident was investigated retrospectively based on (129)I and (137)Cs inventories in soils in Northern Ukraine. To this end, soil samples from 60 settlements were investigated for (129)I, (127)I, and (137)Cs by AMS, ICP-MS and gamma-spectrometry, respectively. Sampling was performed between 2004 und 2007. In those parts of Northern Ukraine investigated here the (129)I and (137)Cs inventories are well correlated, the variability of the individual (129)I/(137)Cs ratios being, however, high. Both the (129)I and (137)Cs inventories in the individual 5 samples for each settlement allowed estimating the uncertainties of the inventories due to the variability of the radionuclide deposition and consequently of the retrospective dosimetry. Thyroid equivalent doses were calculated from the (129)I and the (137)Cs inventories using aggregated dose coefficients for 5-year old and 10-year-old children as well as for adults. The highest thyroid equivalent doses (calculated from (129)I inventories) were calculated for Wladimirowka with 30 Gy for 5-years-old children and 7 Gy for adults. In 35 settlements of contamination zone II the geometric mean of the thyroid equivalent doses was 2.0 Gy for 5-years-old children with a geometric standard deviation (GSD) of 3.0. For adults the geometric mean was 0.47 Gy also with a GSD of 3.0. In more than 25 settlements of contamination zone III the geometric means were 0.82 Gy for 5-years old children with a GSD of 1.8 and 0.21 Gy for adults (GSD 1.8). For 45 settlements, the results of the retrospective dosimetry could be compared with thyroid equivalent doses calculated using time-integrated (131)I activities of thyroids which were measured in 1986. Thus, a critical evaluation of the results was possible which demonstrated the general feasibility of the method, but also the associated uncertainties and limitations.
authors.affiliation: Institut für Radiooekologie und Strahlenschutz (IRS), Leibniz Universität Hannover, Herrenhaeuser Str. 2, D-30419 Hannover, Germany. Electronic address: michel@irs.uni-hannover.de.
authors.forename: R
authors.initials: R
authors.lastname: Michel
authors.affiliation: Institut für Radiooekologie und Strahlenschutz (IRS), Leibniz Universität Hannover, Herrenhaeuser Str. 2, D-30419 Hannover, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Daraoui
authors.affiliation: Institut für Radiooekologie und Strahlenschutz (IRS), Leibniz Universität Hannover, Herrenhaeuser Str. 2, D-30419 Hannover, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Gorny
authors.affiliation: Institut für Radiooekologie und Strahlenschutz (IRS), Leibniz Universität Hannover, Herrenhaeuser Str. 2, D-30419 Hannover, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Jakob
authors.affiliation: Institut für Radiooekologie und Strahlenschutz (IRS), Leibniz Universität Hannover, Herrenhaeuser Str. 2, D-30419 Hannover, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Sachse
authors.affiliation: State University of Agriculture and Ecology, Stari Bulvar 7, Zhitomir 262 001, Ukraine.
authors.forename: L D
authors.initials: LD
authors.lastname: Romantschuk
authors.affiliation: Laboratory of Ion Beam Physics, ETH-Zurich, Otto-Stern-Weg 5, CH-8093 Zurich, Switzerland.
authors.forename: V
authors.initials: V
authors.lastname: Alfimov
authors.affiliation: Laboratory of Ion Beam Physics, ETH-Zurich, Otto-Stern-Weg 5, CH-8093 Zurich, Switzerland.
authors.forename: H-A
authors.initials: HA
authors.lastname: Synal
mesh_terms: D002588:Cesium Radioisotopes / Q000032:analysis*; D047852:Chernobyl Nuclear Accident; D006801:Humans; D007457:Iodine Radioisotopes / Q000032:analysis*; D011829:Radiation Dosage; D011834:Radiation Monitoring; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012990:Soil Pollutants, Radioactive / Q000032:analysis*; D013051:Spectrometry, Gamma; D013961:Thyroid Gland / Q000737:chemistry; D014455:Ukraine
chemical_list: D002588:Cesium Radioisotopes; D007457:Iodine Radioisotopes; D012990:Soil Pollutants, Radioactive
keywords: Accelerator mass spectrometry; Caesium-137; ICP-MS; Iodine-129; Iodine-131; Radionuclide migration; Retrospective dosimetry