RESULTS OF WBC MEASUREMENTS WERE MADE AT RADIOACTIVELY CONTAMINATED TERRITORIES OF UKRAINE IN 1986-2014 (REVISION AND ANALYSIS). / REZUL'TATY LVL6VYMIRIuVAN', PROVEDENYKh NA RADIOAKTYVNO ZABRUDNENYKh TERYTORIIaKh UKRAÏNY U 1986-2014 rr. (REVIZIIa TA ANALIZ).

OBJECTIVE: revision, analysis, and significant improvement of quality of the database of WBC measurements made in1986-2014 at radioactively contaminated territories of Ukraine by the use of renewal of informational gaps andimprovement of the model for assessment of internal exposure doses. MATERIALS AND METHODS: Inthe periodfrom 1986 to 2014 experts of the Whole Body Counters Laboratory of NRCRMaccumulated about 1.5 million results of WBC measurementsof radio-cesium incorporated in the body of personsresiding at the territories which are radioactively contaminated due to Chornobyl accident. Most of measurements(~64 %) were made during the first 15 years after the accident. The most of measurements were made in Kyiv (~23 %),Zhytomyr (~36 %), Rivne (~20 %) and Chernihiv (~5 %) Oblasts. Works on revision of database of WBC measurementsincluded: transformation of data saved in paper format into electronic form, checking for correctness and correspon-dence of information, renewal of lacking information at the fields of database, improvement of the model for eval-uation of internal exposure doses by the data of WBC measurements. In the model for evaluation of revised doses,it is assumed uniform content of radio-cesium during a year. Reference values are used of metabolism parametersand anthropometric human parameters recommended in publications of ICRP. RESULTS: Revised doses have been reconstructed for 1,386,585 records of data base of WBC measurements that fitspecially elaborated criterions for estimation of quality of results. Among them 604,215 records are WBC measure-ments of children and adolescents younger than 18, and 782,370 records correspond to adult inhabitants of Ukraine,most of which reside in Zhytomyr, Kyiv, Rivne and Chenihiv Oblasts. CONCLUSIONS: Obtained results serve as a ground for further works on improvement of models for evaluation of pass-port doses and individualized exposure doses of subjects registered in Ukrainian State Register - of persons thataffected due to Chornobyl accident. Evaluated doses can be used for epidemiological, clinical and other research.

METHODOLOGY OF RECONSTRUCTION OF INDIVIDUALIZED EXPOSURE DOSES FOR PERSONS RESIDING AT RADIOACTIVELY CONTAMINATED TERRITORIES OF UKRAINE. / METODYKA REKONSTRUKTsIÏ INDYVIDUALIZOVANYKh DOZ OPROMINENNIa OSIB, ShchO MEShKAIuT' NA RADIOAKTYVNO ZABRUDNENYKh TERYTORIIaKh UKRAÏNY.

OBJECTIVE: Development of methodology for reconstruction of individualized exposure doses for persons residing atradioactively contaminated after Chornobyl accident territories.Materials and methods of research. The methodology is based on the data of radio-ecological (ground, meal) anddosimetric (WBC measurements) monitoring held in Ukraine in 1986-2013, the results of which are saved in databases of Central Ecological and Dosimetric Register of Radiation Protection Laboratory of NRCRM. It is presentedfour levels of individualization of exposure doses. Each subsequent level of the model is based on the previous oneand takes into account additional parameters, and as a result a model of the next level comprises more number ofexposure situations and provides more accurate estimates. Using the methodology it is necessary to select a modelof such level that enables to solve in the best way the assignments posed before a researcher. For the population ofradioactively contaminated territories, two main ways of exposure are considered: (a) external gamma-exposurefrom radionuclides in the ground, and (b) internal exposure from consumption of radioactively contaminated meal.The dose is evaluated from all the main radionuclides of radioactive accident deposition, and in case of internalexposure after 1986 - only from radio-isotopes of cesium (134Cs and 137Cs). RESULTS: Individualized doses are evaluated for different age groups of population residing in 10 raions of the mostcontaminated after Chornobyl accident Oblasts of Ukraine: Zhytomyr, Kyiv, Rivne and Chernihiv Oblasts. Dose esti-mates are presented weighted by the number of residents in settlements of specific raions. Among them are: thedose for 1986, doses accumulated during the first 15 years after the accident (1986-2000), and during the periodof 32 years after the accident (1986-2017). CONCLUSIONS: Average raion dose reconstructed for adult residents of the most radioactively contaminatedNarodychy Raion of Zhytomyr Oblast in 1986 was 18 mSv, and accumulated during the whole period after the acci-dent was 51 mSv. The lowest doses among abovementioned 10 raions were obtained by persons residing at the ter-ritory of Kozelets and Ripky Raions of Chernihiv Oblast. Average dose for them in 1986 constituted 1.3 and 1.7 mSv,and the one accumulated during 32 years was 6.1 and 6.2, respectively.

Reconstruction of individualized doses of subjects from the Ukrainian State Register - of Persons that Affected due to Chornobyl accident and reside in Korosten raion of Zhytomyr oblast. / REKONSTRUKTsIIa INDYVIDUALIZOVANYKh DOZ SUB'IeKTIV DERZhAVNOGO REIeSTRU UKRAÏNY OSIB, IaKI POSTRAZhDALY VNASLIDOK ChORNOBYL'S'KOÏ KATASTROFY, ShchO PROZhYVAIuT' V KOROSTENS'KOMU RAY̆ONI ZhYTOMYRS'KOÏ OBLASTI.

STUDY OBJECTIVE: To elaborate an ecological dosimetric model of reconstruction individualized exposure doses of subjects from the State Register of Ukraine (SRU) - of persons, affected due to Chornobyl accident and reside at the radioactive contaminated territory of Korosten raion of Zhytomyr Oblast, and to calculate exposure doses for those persons. MATERIALS AND METHODS: In the paper, an ecological dosimetric model is presented which is elaborated in order to individualize exposure doses of people who reside in Korosten raion of Zhytomyr Oblast and are registered in SRU. The model is based on the results of radio ecological and dosimetric monitoring held in the period of 1986-2013 at the territory of northern oblasts of Ukraine. Annual dose over each post accidental year consists of the two compo nents: (a) annual effective dose of external gamma exposure (due to radioactive fallout on the ground), and (b) internal exposure of the whole body (due to consumption of meal contaminated by radioactive isotopes). For 1986, the dose of internal exposure is evaluated out of all main radionuclides of radioactive accidental fallout, and after 1987 only for radioisotopes of caesium (134Cs and 137Cs). The parameterization of the model is based on the pre vious experience in working out a complex of ecological dosimetric models for estimation of referent exposure doses of Ukrainian population. RESULTS AND CONCLUSIONS: Individualized doses of external and internal exposure (annual and accumulated) are estimated for the population of various age groups that resides in the settlements of Korosten raion (totally about 100 settlements). Separately the doses are presented for rural settlements of the raion and for the city of Korosten for each year of the post accidental period of 1986-2016. Estimates of doses are given that were accumulated: (a) during 15 years just after the accident, (b) for the period of 2000-2016, and (c) for 30 year period after the acci dent. Mean dose accumulated for 30 years after the Chornobyl accident by residents of rural settlements of Korosten raion is estimated as 19.8 mSv, and for inhabitants of the Korosten city as 20.9 mSv. On condition of permanent res idence in the raion, residents of about 66 % settlements of Korosten raion accumulated the doses in the interval 5 20 mSv during 30 years after the accident. For the residents of about 25 % settlements the accumulated dose is in the interval 20-50 mSv, and for 7 % of settlements it exceeds 50 mSv.

Generalized results of individualized exposure doses reconstruction for the subjects of Ukrainian State Register of persons, affected due to Chernobyl accident. / UZAGAL'NENI REZUL'TATY REKONSTRUKTsIi INDYVIDUALIZOVANYKh DOZ SUB'IeKTIV DERZhAVNOGO REIeSTRU UKRAiNY OSIB, IaKI POSTRAZhDALY VNASLIDOK ChORNOBYL'S'KOi KATASTROFY.

Since 2007, the department of dosimetry of NRCRM has been working for to supply the Ukrainian State Register (SRU) of persons affected due to Chernobyl accident by exposure doses estimations. As of now, the individualization of doses has been performed for nine raions located in Kyiv, Zhytomyr, Rivne and Chernihiv oblasts. The structure of raion-specific models used for the reconstruction of individualized doses was described in detail in the previous 19-th issue of this journal (2014). The choice conditions for persons from the SRU using which for each raion there was formed a contingent of persons for whom the dose could be reconstructed. During the period of 2007-2015, the individualized dose was reconstructed for 244226 persons in 9 raions, representing ~ 58% of all registered in the SRU inhabitants of the raions. The calculation results were transferred to the SRU in formats adapted to the common database structure of the SRU. For each person who satisfied the conditions of selection there were estimated: (1) possible absorbed internal exposure dose of the thyroid by radioiodine in 1986 (assuming that the person in 1986 lived in the same village and was enlisted in the SRU); (2) annual doses of external, internal and total exposure of the whole body for a period of observation in the SRU; (3) total exposure dose of whole body accumulated during the period of observation in the SRU; (4) the total cumulative dose of feasible exposure during the period since 1986 till the decision to be registered in the SRU. There are presented the generalized results of the SRU subjects distribution for different raions in dependence on intervals of doses accumulated at different periods after the accident. The raion matrix tables show the dynamics of accumulation of doses by the SRU subjects both for their stay on the account and for the period of their possible residence registration in the settlement since 1986. The directions for further research to be implemented for increasing the number of persons for whom it is possible to calculate individualized dose have been formulated.