ESR dosimetry study of population in the vicinity of the Semipalatinsk Nuclear Test Site

A tooth enamel electron spin resonance (ESR) dosimetry study was carried out with the purpose of obtaining the individual absorbed radiation doses of population from settlements in the Semipalatinsk region of Kazakhstan, which was exposed to radioactive fallout traces from nuclear explosions in the Semipalatinsk Nuclear Test Site and Lop Nor test base, China. Most of the settlements are located near the central axis of radioactive fallout trace from the most contaminating surface nuclear test, which was conducted on 29 August 1949, with the maximum detected excess dose being 430 ± 93 mGy. A maximum dose of 268 ± 79 mGy was determined from the settlements located close to radioactive fallout trace resulting from surface nuclear tests on 24 August 1956 (Ust-Kamenogorsk, Znamenka, Shemonaikha, Glubokoe, Tavriya and Gagarino). An accidental dose of 56 ± 42 mGy was found in Kurchatov city residents located close to fallout trace after the nuclear test on 7 August 1962. This method was applied to human tooth enamel to obtain individual absorbed doses of residents of the Makanchi, Urdzhar and Taskesken settlements located near the Kazakhstan–Chinese border due to the influence of nuclear tests (1964–1981) at Lop Nor. The highest dose was 123 ± 32 mGy

Tooth enamel EPR dosimetry: optimization of EPR spectra recording parameters and effect of sample mass on spectral sensitivity

conditions were optimized. The uncertainty of dose determination was obtained as the mean square deviation of doses, determined with the use of a spectra deconvolution program, from the nominal doses for ten enamel samples irradiated in the range from 0 to 500 mGy. The spectra were recorded at different microwave powers and accumulation times. It was shown that minimal uncertainty is achieved at the microwave power of about 2 mW for a used spectrometer JEOL JES-FA100. It was found that a limit of the accumulation time exists beyond which uncertainty reduction is ineffective. At an established total time of measurement, reduced uncertainty is obtained by averaging the experimental doses determined from recorded spectra following intermittent sample shaking and sample tube rotation, rather than from one spectrum recorded at longer accumulation time. The effect of sample mass on the spectrometer’s sensitivity was investigated in order to find out how to make appropriate corrections

Tooth enamel EPR dosimetry: optimization of EPR spectra recording parameters and effect of sample mass on spectral sensitivity

conditions were optimized. The uncertainty of dose determination was obtained as the mean square deviation of doses, determined with the use of a spectra deconvolution program, from the nominal doses for ten enamel samples irradiated in the range from 0 to 500 mGy. The spectra were recorded at different microwave powers and accumulation times. It was shown that minimal uncertainty is achieved at the microwave power of about 2 mW for a used spectrometer JEOL JES-FA100. It was found that a limit of the accumulation time exists beyond which uncertainty reduction is ineffective. At an established total time of measurement, reduced uncertainty is obtained by averaging the experimental doses determined from recorded spectra following intermittent sample shaking and sample tube rotation, rather than from one spectrum recorded at longer accumulation time. The effect of sample mass on the spectrometer’s sensitivity was investigated in order to find out how to make appropriate corrections

The influence of the Lop Nor Nuclear Weapons Test Base to the population of the Republic of Kazakhstan

Abstract The method of electron spin resonance (ESR) dosimetry was applied to human tooth enamel to obtain estimates of individual absorbed dose for residents of Makanchi, Urdzhar and Taskesken settlements located near the Kazakhstan–Chinese border (about 400 km to the South–East, from the Semipalatinsk Nuclear Test Site (SNTS) and about 1000 km from the Lop Nor Nuclear Weapons Test Base, China). Since the ground and atmospheric nuclear tests (1964–1981) at Lop Nor, the people residing in these settlements are believed to have been heavily exposed to radioactive fallout. Tooth samples had been extracted for medical reasons during the course of ordinary dental treatment. The village of Kokpekty, located 400 km to the South–east of the SNTS, was chosen as the control group since it has not been subjected to any radioactive contamination. The mean excess doses in tooth enamel obtained after subtraction of the contribution of natural background radiation do not exceed 62 ± 28 mGy, 64 ± 30 mGy, 49 ± 27 mGy and −19 ± 36 mGy for all ages of the residents of Makanchi, Urdzhar, Taskesken and the control village of Kokpekty, respectively

Application of UV-Vis Optical Spectroscopy and X-ray Diffraction Methods to Describe the Effect of Alpha-Emitting Radionuclides (Radon) When They Are Detected by Solid-State Film Detectors

This work aims to evaluate the application of optical and X-ray spectroscopy methods to determine the effect of alpha-emitting radionuclides on the properties of solid-state nuclear track detectors (SSNTD) based on nitrocellulose during their detection. The proposed estimation methods are alternative methods to standard technologies, making it possible to determine the concentration of radon and its decay products without the chemical etching of film detectors and subsequent direct counting of the formed latent tracks from interacting particles. During the research, it was found that the use of optical spectroscopy and X-ray diffraction methods makes it possible to qualitatively determine the irradiation effect on changes in the properties of film detectors when α-particles with different energies pass through them. At the same time, a comparison of the data of optical spectroscopy, X-ray diffraction and the visualization of latent tracks after chemical etching made it possible to establish that a part of the registered α-particles in living quarters has an energy of less than 2.5 MeV, which is not enough to pass through the polymer film of the detector, as a result of which well-like tracks are formed. An increase in the intensity of the interference bands in the region above 700 nm and a decrease in the intensity of diffraction reflection characterized the changes in optical transmission. The penetration of the α-particles through the detecting film decreases the film’s transmission capacity, forming an anisotropic change in diffraction reflections associated with a change in the film’s structure and defective fractions distorting the molecular structure

Study of Radiation Embitterment and Degradation Processes of Li2ZrO3 Ceramic under Irradiation with Swift Heavy Ions

The work is devoted to the study of radiation damage and subsequent swelling processes of the surface layer of Li2ZrO3 ceramics under irradiation with heavy Xe22+ ions, depending on the accumulation of the radiation dose. The samples under study were obtained using a mechanochemical synthesis method. The samples were irradiated with heavy Xe22+ ions with an energy of 230 MeV at irradiation fluences of 1011–1016 ion/cm2. The choice of ion types is due to the possibility of simulating the radiation damage accumulation processes as a result of the implantation of Xe22+ ions and subsequent atomic displacements. It was found that, at irradiation doses above 5 × 1014 ion/cm2, point defects accumulate, which leads to a disordering of the surface layer and a subsequent decrease in the strength and hardness of ceramics. At the same time, the main process influencing the decrease in resistance to radiation damage is the crystal structure swelling as a result of the accumulation of defects and disordering of the crystal lattice

Study of Radiation Embitterment and Degradation Processes of Li₂ZrO₃ Ceramic under Irradiation with Swift Heavy Ions

The work is devoted to the study of radiation damage and subsequent swelling processes of the surface layer of Li2ZrO3 ceramics under irradiation with heavy Xe22+ ions, depending on the accumulation of the radiation dose. The samples under study were obtained using a mechanochemical synthesis method. The samples were irradiated with heavy Xe22+ ions with an energy of 230 MeV at irradiation fluences of 1011–1016 ion/cm2. The choice of ion types is due to the possibility of simulating the radiation damage accumulation processes as a result of the implantation of Xe22+ ions and subsequent atomic displacements. It was found that, at irradiation doses above 5 × 1014 ion/cm2, point defects accumulate, which leads to a disordering of the surface layer and a subsequent decrease in the strength and hardness of ceramics. At the same time, the main process influencing the decrease in resistance to radiation damage is the crystal structure swelling as a result of the accumulation of defects and disordering of the crystal lattice

Formation of different types of paramagnetic centers in the alanine dosimeters exposed to alpha and gamma radiation - Study byEPR spectroscopy

International audienceEPR spectra of alanine dosimeters irradiated by gamma-rays and by alpha-particles were measured at different microwave power. The spectra were decomposed into three components corresponding to different stable radiation-induced radicals. Different ratio of the components was obtained for gamma- and alpha-irradiated alanine. The observed effect can be used for discrimination of the contribution of alpha- and gamma-radiationin mixed radiation field. That may be useful for control of dose at phantom experiments with neutron boron capture therapy, performed in mixed neutron-gamma field in which alpha-particles are emitted through neutrons capture reaction with boron

Interlaboratory comparison on Tooth Enemel Dosimetry on Semipalatinsk Region:Part1,General View

Interlaboratory comparison on Tooth Enamel Dosimetry on Semipalatinsk Region:Part1,General View\nM.Hoshi(1)S.toyoda(2)A.Ivannikov(3)K.Zhumadilov(1)A.Fukumura(4)K.Apsalikov(5)Zh.S.Zhumadilov(6)S.Bayankin(7)V.Chumak(8)B.Ciesielski(9)V.De.Coste(10)S.Endo(1)P.Fattinbene(10)D.Ivanov(7)V.Kirillov(11)C.A.Mitchell(13)S.Onori(10)M.Penkowski(9)S.P.Pivovarov(13)A.Rumanyukha(12)A.B.Rukhin(13)K.Sehultka(9)T.A.Seredavina(13)S.Sholom(8)V.Skvortsov(3)V.Stepanenko(3)K.Tanaka(1)F.Trompier(14)A.Wieser(15)G.Wolakiewicz(9)\n(1) Research Institute for Radiation Biology and Medicine,Hiroshima University Hiroshima(2) Okayama University of Science,Okayama,Japan(3) Medical Radiological Reserch Center Obninsk,Russia(4) National Insutitute of Radiological Sciences, Chiba,Japan(5) Reserch Institute of Radiation Medicene and Hygiene, Semipalatinsk,Kazakhstan(6) Semipalatinsk State Medical Academy,Semipalatinsk,Kazakhstan(7) Insutitute of Metal Physics, Ekaterinburg,Russia(8) Insutitute is;Scientific Center for Radiation Medicine,Kiev,Ukraine(9) Medical University of Gdansk, Gdansk,Poland(10) Istituto Superiore di Snita and Istituto Nazionale di Fisica Nucleare, Rome,Italy(11) Belarusian State Medical University, Minsk, Belarus(12) Uniformed Service University of Health Sciences, Bethesda,USA(13) Institute of Nuclear Physics of National Nuclear Center of Kazakhstan, Almary, Kazakhstan(14) Institut de Radioprotection et Surete Nucleaire, Fontenay-aux-rosese,France(15) GSF-National Research Center for Environment and Health,Institute of Radiation Protection, Neuherberg,Germany\n2. Corresponding auther:[email protected],ac,jp\nSince ESR/EPR method was found to be useful for retrospective dosimetry of human teeth,it has been the issue how accurately the doses can be obtained.There have already been three interlaboratory comparison projects organized where successful resultes were abtained, However,whichi fantor gives variation in the nominal doses is still unknown.In the present intercomparison,the human teeth from acttual radiation accidents were analyzed in different laboratories to see how chose the obtained doses are to each other.Each Laboratory used the samemeasurement condition together with optionally their own Measurement doncition. This will tell the difference in using diffent spectrometeres,measurement conditions, and data processing irradiated tooth samples will also be examined to check if the methods work properly.\nThe 14 tooth enamel samples were provided from Semipalatinsk region receivedsome amount of accidental doses estimated to be from 50 to 500 mHy. For the calibrariton for these samples,a set of eight irradiated samples are prepared from pooled enemal obtained from teeth collected in control territory of Samipalatinsk region.In addition, ten test samples from five Japanese molar teeth are provided. Each tooth was cut in half and five halves were irradiated to known doses between 100 and 300 mGy and the other halves were not as it was done in the 3rd intencomparison.The results of the measurements will be presented.The 2nd　Interenational Conference on Biodosimetry and 7th International Symposium on EPR Dosimetry and App