Fig 2 - uploaded by Valeriy Fedorovich Stepanenko
Content may be subject to copyright.
Source publication
Electron paramagnetic resonance (EPR) dosimetry is a physical method for the assessment of absorbed dose from ionising radiation. It is based on the measurement of stable radiation induced radicals in human calcified tissues (primarily in tooth enamel). EPR dosimetry with teeth is now firmly established in retrospective dosimetry. It is a powerful...
Citations
... In vivo electron spin resonance (ESR) is considered to be one of the most applicable techniques suited to these types of events [6][7][8]. ESR measures radiationinduced paramagnetic defects in tooth enamel, the concentration of which is known to proceed linearly with the received radiation dose, ranging from 50 mGy [9] up to hundreds of Gy [10], and to reach saturation at about 100 kGy [11]. It is perhaps the only physical method that can differentiate among doses with sufficient sensitivity and resolution to classify individuals into categories for treatment, and with sufficient accuracy to facilitate decision-making regarding medical treatment [12,13]. ...
... Other portions were irradiated using a 60 Co gamma source at the SNRC Space and Materials Department at doses of 10, 50, 100, and 500 Gy. For in vitro measurements, such as those carried out in this work, the common practice for preparing enamel samples involves mechanical and chemical etching [10] that results in the removal of most of the dentin. Accordingly, we cut the teeth's crowns from the roots using a diamond knife (Fig. 1b). ...
Large-scale triage after major radiological events, such as nuclear reactor accidents, requires a method of ionizing radiation dose estimation called retrospective biodosimetry (RBD) to detect doses in the range of 0.5–8 Gy. A well-known technique for performing RBD is electron spin resonance (ESR), which can be used to measure radiation-induced paramagnetic defects in the enamel of the teeth. The concentration of these defects is linearly correlated with radiation doses in the applicable range. Despite its great potential and proven results when applied to extracted teeth, ESR still struggles to provide accurate in vivo readings. This is mainly because all available ESR-based RBD methods rely on quantitative signals for calculating the concentration of paramagnetic defects in tooth enamel to evaluate the dose. This requires an accurate knowledge of the volume of the measured enamel, which is very difficult to achieve in live subjects (since teeth also include dentin and possibly cavities). Here, we examine radiation-induced paramagnetic defects in the enamel layer of human teeth using advanced pulsed ESR methods, with the ultimate goal of supporting the development of an innovative practical RBD device for in vivo use. We employ a variety of pulsed ESR techniques, such as ESR measurements of spin–spin relaxation time (T2), ESR monitoring of instantaneous diffusion decay time (TID), and dipolar ESR spectroscopy, to explore their possible use to quantify the irradiation dose. Moreover, we develop a special resonator for teeth measurements that make use of such pulse techniques to overcome the constrains of small signal magnitudes and short coherence times. Our results show a good correlation between measured values of T2, TID, and the irradiated dose, but further work is required to improve the robustness, accuracy, and sensitivity of the methods presented before they could possibly be applied for in vivo measurements in typical doses of ~ 2–8 Gy. These findings and approaches may be used in the future for the development of a RBD device to evaluate ionizing radiation doses without prior knowledge of the measured enamel volume.
... Most importantly, tooth enamel and dentin are lifetimes biological dosimeters because the radiation-induced free radical centers (signals) are stored in tooth enamel or bone for many thousands of years ($10 7 years at 25 C) without any disturbance [4,23]. So, the measurement of radiation dose in tooth enamel would provide accurate measurements of dose, and tooth enamel is an ideal material for retrospective and accident dose assessment [4,6,10,22,24]. ...
... Additionally, a human tooth records radiation doses throughout life and cannot be forgotten like our standard dosimeters. Therefore, several studies have demonstrated that EPR tooth dosimetry is a powerful method for retrospective and accident dosimetry, which can also provide information on historical and chronic exposures to individuals exposed to ionizing radiation from nuclear power plants or radiological accidents [24]. As a result, EPR tooth retrospective and emergency dosimetry are essential to epidemiological studies and treatment plans for people suffering from acute radiation syndrome or radiation toxicity [6]. ...
... As a result, EPR tooth retrospective and emergency dosimetry are essential to epidemiological studies and treatment plans for people suffering from acute radiation syndrome or radiation toxicity [6]. Essentially, this technique helps measure relatively low dose exposures or when conventional dosimeters are unavailable or out of order in the case of nuclear accidents, terrorist attacks, or other chronic exposure [24]. Determining chronic or acute low doses is vital because it may have adverse health effects when exposure occurs over a long time [25]. ...
When tooth enamel is exposed to ionizing radiation, it generates a dose-dependent concentration of free radical centers (i.e., unpaired electrons). The concentration of these free radical centers is identified and quantified using electron paramagnetic resonance (EPR) spectroscopy in the form of an EPR spectrum. The intensity of the spectrum is proportional to the absorbed dose. Four international intercomparisons have already demonstrated that the EPR tooth enamel dosimetric technique is reliable for retrospective dose assessment in acute and chronic exposure scenarios. Additionally, EPR dosimetry is regarded same as a gold standard for reconstructing the total lifetime dose to individuals using tooth enamel. The accuracy and reproducibility of EPR dose reconstruction depend on the sample preparation, spectrum acquisition, and EPR spectra analysis techniques. So, this paper reviews some of the widely applied and accepted laboratory protocols or methodologies for the EPR dosimetric methods. The minimum detection limit in tooth enamel using this technique was 30 mGy. So, the goal of this review is to share these protocols so that it would be easy to reconstruct the accident doses or chronic exposures with reliable accuracy and precision. Due to the availability of spectrometers, moderate price, and not being much influenced by the small amount of moisture in a sample, the X-band continuous wave(CW) EPR spectrometer has been used in many historical and accident dose reconstructions. Data accuracy, detection limit, and usefulness depend on systematic analysis, highly skillful EPR technician, and uncertainty analysis.
... 1−11 EPR dosimetry is utilized for radiation dose reconstruction, 1,2,12 food irradiation, 13,14 nuclear medicine, 15 and archaeological dating. 1,4,16,17 Because of its high sensitivity and accuracy, EPR dosimetry of tooth enamel has also been successfully employed in retrospective studies of several accidents involving radioactivity, e.g., Hiroshima and Nagasaki, 18,19 Chernobyl, 20−22 Urals, 23 Maryland, 24 and Fukushima, 25 to determine the radiation dose absorbed by individuals. In retrospective EPR dosimetry, the concentration of radiationinduced stable radicals in tooth enamel is linearly proportional to the absorbed dose received over the radiation range of 10 mGy to 100 Gy, which is pertinent to radiation accident doses. ...
... 36−38 Unfortunately, employing tooth enamel in this context faces major challenges because of factors that affect the quality of the enamel 4,8,39 and the dosimetry results because of additional overlapping EPR signals. 1,3,14 To circumvent the issues with biologically derived tooth enamel, synthetically-prepared carbonated hydroxyapatite (CHA) has been used to mimic the radiation response of tooth enamel. 40−43 Choice and control of the CHA synthesis method impacts the resultant material properties, offering a means to improve the carbonate-derived radical yield and homogeneity. ...
Ionizing radiation-induced paramagnetic defects in calcified tissues like tooth enamel are indicators of irradiation dose. Hydroxyapatite (HA), the principal constituent in these materials, incorporates a variety of anions (CO32-, F-, Cl-, and SiO44-) and cations (Mn2+, Li+, Cu2+, Fe3+, Mg2+, and Na+) that directly or indirectly contribute to the formation of stable paramagnetic centers upon irradiation. Here, we used an underexploited synthesis method based on the ambient temperature setting reaction of a self-hardening calcium phosphate cement (CPC) to create carbonate-containing hydroxyapatite (CHA) and investigate its paramagnetic properties following γ-irradiation. Powder X-ray diffraction and IR spectroscopic characterization of the hardened CHA samples indicate the formation of pure B-type CHA cement. CHA samples exposed to γ-radiation doses ranging from 1 Gy to 150 kGy exhibited an electron paramagnetic resonance (EPR) signal from an orthorhombic CO2•- free radical. At γ-radiation doses from 30 to 150 kGy, a second signal emerged that is assigned to the CO3•- free radical. We observed that the formation of this second species is dose-dependent, which provided a means to extend the useful dynamic range of irradiated CHA to doses >30 kGy. These results indicate that CHA synthesized via a CPC cement is a promising substrate for EPR-based dosimetry. Further studies on the CHA cement are underway to determine the suitability of these materials for a range of biological and industrial dosimetry applications.
... Biodosimetry is based on measuring the changes in the body induced by ionizing radiation (IAEA, 2002;2011;ISO, 2008;2014;2020b;Alexander et al., 2007;Rothkamm et al., 2013;. Such tools are mostly useful after external exposure to ionizing radiation rather than following internal exposures, for which other methods are more pertinent (Rojas-Palma et al., 2009;Giussani et al., 2020). ...
As COVID-19 emerged, there are parallels between the responses needed for managing SARS-CoV-2 infections and radiation injuries. While some SARS-CoV-2-infected individuals present as asymptomatic, others exhibit a range of symptoms including severe and rapid onset of high-risk indicators of mortality. Similarly, a variety of responses are also observed after a radiological exposure depending on radiation dose, dose heterogeneity, and biological variability. The impact of acute radiation syndrome (ARS) has guided the identification of many biomarkers of radiation exposure, the establishment of medical management strategies, and development of medical countermeasures in the event of a radiation public health emergency. Biodosimetry has a prominent role for identifying exposed persons during a large scale radiological emergency situation. Identifying exposed individuals is also critical in the case of pandemics such as COVID-19, with the additional goal of controlling the spread of disease. Conclusions and significance: IABERD has taken advantage of its competences in biodosimetry to draw lessons from current practices of managing the testing strategy for nuclear accidents to improve responses to SARS-CoV-2. Conversely, lessons learned from managing SARS-CoV-2 can be used to inform best practices in managing radiological situations. Finally, the potential need to deal with testing modalities simultaneously and effectively in both situations is considered.
... While the method of the electron spin resonance (ESR) retrospective dosimetry has been established for human tooth enamel (e.g. IAEA (1) , Fattibene and Callens (2) ), the methods for mammal tooth enamel have also been investigated, with having an advantage that obtaining mammal teeth is not so difficult as human teeth. They have been shown to be available with cattle (3,4) , mice (3) , deer (5) , boar (6) , boison, moo, bear and fox (7) , and rodent (8) . ...
The method of electron spin resonance (ESR) tooth enamel dosimetry was successfully applied to cattle molar teeth exposed in the accident of Fukushima Dai-ichi atomic power plants. Total of 10 samples from 5 cattle were examined and the doses were retrospectively reconstructed to be up to 1.2 Gy (enamel dose). The dose values are roughly consistent with those estimated from the monitored environmental dose rate and the durations of the exposure. This first successful result on ESR reconstruction of doses in the actual radiation accident indicates that ESR tooth enamel dosimetry with cattle is practically useful in the dose range of ~1 Gy.
... Moreover, these parameters are also helpful to determine the absorbed dose by the target material. Recent studies have shown that the human teeth can be used as a dosimeter material [20][21][22]. For dosimetric purposes tooth must not have any material. ...
Radiological parameters of composite filler, zirconium and acrylic coating materials used in dental treatment are determined. Mass attenuation coefficients (μ m ) of these materials have been experimentally determined for 9 different gamma energies emitting from Ra-226 and Eu-152 radioactive sources by using gamma spectrometry system with (3″ × 3″) NaI(Tl) detector. Effective atomic and electron numbers (Z eff , N eff ), atomic and electronic cross sections (σ t,a and σ t,el ) have been also obtained for these materials. The obtained results were compared with the NIST database and EGSnrc Monte Carlo (MC) code. It is found that general trends of these parameters are consistent with the literature. The maximum attenuation occurs at 122 keV and it has been found for 1 mm thick samples that 21%, 10% and 2% of the incident radiation have been absorbed by the zirconium, composite and acrylic samples, respectively.
... La datación de un material arqueológico por Resonancia Paramagnética Electrónica (EPR) se basa en la determinación de la concentración de centros paramagnéticos generados por la radiación ionizante en ella. Esta técnica forma parte del grupo de métodos paleodosimétricos, junto con los basados en los fenómenos de luminiscencia (Rink, 1997;Jonas, 1997;Ikeya, 1993;Ikeya, 1975;Schwarcz, Grün & Tobias, 1994;Grün & Stringer, 1991;Grün, 1997;Apaydın, 1991;Bruker, 2001;Wertz & Bolton, 1971;Atherton, 1973;Brik et al., 2000;Rosiers, 1990;Ishii & Ikeya, 1990;Lee, Rink & Schwarcz, 1997;Polyakov et al., 1995;Wieser et al., 1988;IAEA, 2002;Ikeya, 1993;Schauer et al., 1994;Romanyukha et al. 1994;Egersdörfer, Wieser & Muller, 1996;Haskell, Hayes & Kenner, 1996;Regulla, 2000;Magdalena, Ryszard & Helena, 2000). ...
In this exploratory project, it has focused on the possibility of providing detailed information on the archaeological material incorporated into the Domestic Units of the Muisca community of the archaeological site of Suta in Valle de Leyva in the Department of Boyacá of Colombia and the anthropological discussions about longevity. To fulfill this approach, a standard ceramic dating protocol was established, using the Electronic Paramagnetic Resonance - EPR equipment to reveal the chronostratigraphy of the Suta site, and thus, strengthening chronological aspects of the Muisca society in Colombia. A total of nine ceramic fragments were analyzed with the EPR equipment and a total of six successful dates were obtained corresponding to the Early Muisca and Late Muisca periods. The dating results of the fragments are consistent with each other and show coherence with the radiocarbon dates of other Muisca sites. At the end of this transdisciplinary research, a successful standard Muisca ceramic dating protocol was established that promotes the usefulness of the EPR equipment as a worthy chronometric tool to construct and refine chronologies in Colombian archeology. At the same time it was possible to calculate the longevity of one of the four residential units of the Suta site.
... EPR biodosimetry consisted of sample collection, sample preparation, EPR measurements, dose calibration and determination of absorbed dose according to International Atomic Energy Agency (IAEA) protocol (8) . The same 'universal' calibration curve was used for all EPR dose measurements without additional irradiation of samples (9) . ...
... This study represents comparative analysis of the two of the most reliable biodosimetry assays using sampling blood and tooth enamel in the same radiation victim. Both cytogenetic and EPR assays were performed in radiation cytogenetic laboratory and laboratory experimental nuclear medicine of MRRC, Obninsk, according to IAEA protocols (8,12) . For the first time, the broad range of whole-body exposure to dose ranged from 0.01 to 9.3 Gy was analysed in the framework of the same study. ...
... EPR biodosimetry consisted of sample collection, sample preparation, EPR measurements, dose calibration and determination of absorbed dose according to International Atomic Energy Agency (IAEA) protocol (8) . The same 'universal' calibration curve was used for all EPR dose measurements without additional irradiation of samples (9) . ...
... This study represents comparative analysis of the two of the most reliable biodosimetry assays using sampling blood and tooth enamel in the same radiation victim. Both cytogenetic and EPR assays were performed in radiation cytogenetic laboratory and laboratory experimental nuclear medicine of MRRC, Obninsk, according to IAEA protocols (8,12) . For the first time, the broad range of whole-body exposure to dose ranged from 0.01 to 9.3 Gy was analysed in the framework of the same study. ...
... EPR biodosimetry consisted of sample collection, sample preparation, EPR measurements, dose calibration and determination of absorbed dose according to International Atomic Energy Agency (IAEA) protocol (8) . The same 'universal' calibration curve was used for all EPR dose measurements without additional irradiation of samples (9) . ...
... This study represents comparative analysis of the two of the most reliable biodosimetry assays using sampling blood and tooth enamel in the same radiation victim. Both cytogenetic and EPR assays were performed in radiation cytogenetic laboratory and laboratory experimental nuclear medicine of MRRC, Obninsk, according to IAEA protocols (8,12) . For the first time, the broad range of whole-body exposure to dose ranged from 0.01 to 9.3 Gy was analysed in the framework of the same study. ...
The goal of this study was to compare dose estimates from electron paramagnetic resonance (EPR) dosimetry with teeth and cytogenetic
dosimetry with blood lymphocytes for 30 victims of radiation accidents. The whole-body exposures estimated by tooth enamel
EPR dosimetry were ranging from 0.01 to 9.3 Gy. Study group comprised victims exposed to acute and prolonged irradiation at
high and low dose rate in different accidents. Blood samples were taken from each of them for cytogenetic analysis. Aberrations
were scored and analysed according to International Atomic Energy Agency (IAEA) guidelines for conventional and FISH analysis.
Tooth samples were collected in dental clinics after they had been extracted during ordinary practice. EPR dosimetry was performed
according to the IAEA protocol. EPR dosimetry showed good correlation with dosimetry based on chromosomal analysis. All estimations
of cytogenetic dose below detection limit coincide with EPR dose estimates within the ranges of uncertainty. The differences
between cytogenetic and EPR assays may occur in a case of previous unaccounted exposure, non-homogeneous irradiation and due
to contribution to absorbed dose from neutron irradiation.
