Justification and Application of Sufficiency Criterion for Measuring the Activity of Uranium Radioisotopes in Biological Samples
Authors:
1.
A.I. Burnasyan Federal Medical Biophysical Center, Moscow, Russia
National Research Nuclear University MEPhI (Moscow Engineering Physics Institute). Moscow, Russia
National Research Nuclear University MEPhI (Moscow Engineering Physics Institute). Moscow, Russia
2.
A.I. Burnasyan Federal Medical Biophysical Center (FMBC) FMBA
(Leading Researcher)
employee
Russian Federation
employee
Russian Federation
3.
A.I. Burnasyan Federal Medical Biophysical Center, Moscow, Russia
Type:
Article
Pages:
from 70
to 76
Status:
Published
Received:
13.09.2021
Accepted:
13.09.2021
Published:
13.09.2021
Subject area:
UDK 61 Медицина. Охрана здоровья
GRNTI 76.33 Гигиена и эпидемиология
GRNTI 76.03 Медико-биологические дисциплины
OKSO 31.06.2001 Клиническая медицина
OKSO 31.08.08 Радиология
OKSO 32.08.12 Эпидемиология
OKSO 14.04.02 Ядерные физика и технологии
BBK 534 Общая диагностика
BBK 51 Социальная гигиена и организация здравоохранения. Гигиена. Эпидемиология
TBK 5712 Медицинская биология. Гистология
TBK 5734 Медицинская радиология и рентгенология
TBK 6212 Радиоактивные элементы и изотопы. Радиохимия
TBK 5708 Гигиена и санитария. Эпидемиология. Медицинская экология
GRNTI 76.33 Гигиена и эпидемиология
GRNTI 76.03 Медико-биологические дисциплины
OKSO 31.06.2001 Клиническая медицина
OKSO 31.08.08 Радиология
OKSO 32.08.12 Эпидемиология
OKSO 14.04.02 Ядерные физика и технологии
BBK 534 Общая диагностика
BBK 51 Социальная гигиена и организация здравоохранения. Гигиена. Эпидемиология
TBK 5712 Медицинская биология. Гистология
TBK 5734 Медицинская радиология и рентгенология
TBK 6212 Радиоактивные элементы и изотопы. Радиохимия
TBK 5708 Гигиена и санитария. Эпидемиология. Медицинская экология
Language:
Russian
Keywords:
individual monitoring programme, alpha spectrometry, sufficiency criterion, decision threshold, detection limit, confidence interval
Abstract (English):
Purpose: Ensuring the fulfillment of the sufficiency n criterion when measuring the activity of uranium radionuclides in biological samples carried out within the individual monitoring programme by calculation of the uncertainty and characteristics limits for measurements. Material and methods: The sufficiency criterion definition is given, which determines the maximum value of the decision threshold for measurements carried out for the individual monitoring of workers at which the fact of non-exceeding of the annual dose limit or permissible level takes place, taking into account the uncertainty of the dose assessment. A model approach is used to calculate the sufficiency criterion and characteristics limits when measuring the radioactive material excrected by individual workers. The model approach consisted in the development of a calculation model based on the functional dependence of measured input values on the process of radiochemical preparation and subsequent spectrometric measurement of the sample. Results: A model has been developed for calculating the activity of uranium radionuclides 234U, 235U and 238U in a biological sample based on the description of the procedure for spectrometric measurement, which consisted in the deposition by the electrolytic method on the target after chromatographic extraction of uranium from the urine sample. The reference radioactive solution of the 232U radionuclide added to the sample as a reference point for determining the efficiency of uranium radionuclide separation (chemical yield). Equations are obtained for calculating the values of the decision threshold and the detection limit for the total activity of the above alpha-emitting uranium radionuclides. Using these equations, the dependence of the decision threshold and the detection limit on measurement time is determined for the given input data. This allows planning the measurement time at which the activity of uranium radionuclides in the sample can be determined reliably or at which the sufficiency criterion of the measurement method will be provided (necessary in the case when the activity is not detected, that is, the measurement result is less than the decision threshold). The values of the activity of uranium radionuclides 234U, 235U and 238U and the corresponding characteristics limits for the measurement were calculated on the basis of a real example of spectrometric measurement of the activity of uranium radionuclides in a sample. Conclusion: Ensuring the fulfillment of the sufficiency criterion when measuring the activity of uranium radionuclides in biological samples is achieved by the correct determination of the sample measurement time. This is determined by time dependence analysis of the characteristics limits (the decision threshold and the detection limit ) for the measurement of the total activity of the above alpha-emitting uranium radionuclides 234U, 235U and 238U.
Purpose: Ensuring the fulfillment of the sufficiency n criterion when measuring the activity of uranium radionuclides in biological samples carried out within the individual monitoring programme by calculation of the uncertainty and characteristics limits for measurements. Material and methods: The sufficiency criterion definition is given, which determines the maximum value of the decision threshold for measurements carried out for the individual monitoring of workers at which the fact of non-exceeding of the annual dose limit or permissible level takes place, taking into account the uncertainty of the dose assessment. A model approach is used to calculate the sufficiency criterion and characteristics limits when measuring the radioactive material excrected by individual workers. The model approach consisted in the development of a calculation model based on the functional dependence of measured input values on the process of radiochemical preparation and subsequent spectrometric measurement of the sample. Results: A model has been developed for calculating the activity of uranium radionuclides 234U, 235U and 238U in a biological sample based on the description of the procedure for spectrometric measurement, which consisted in the deposition by the electrolytic method on the target after chromatographic extraction of uranium from the urine sample. The reference radioactive solution of the 232U radionuclide added to the sample as a reference point for determining the efficiency of uranium radionuclide separation (chemical yield). Equations are obtained for calculating the values of the decision threshold and the detection limit for the total activity of the above alpha-emitting uranium radionuclides. Using these equations, the dependence of the decision threshold and the detection limit on measurement time is determined for the given input data. This allows planning the measurement time at which the activity of uranium radionuclides in the sample can be determined reliably or at which the sufficiency criterion of the measurement method will be provided (necessary in the case when the activity is not detected, that is, the measurement result is less than the decision threshold). The values of the activity of uranium radionuclides 234U, 235U and 238U and the corresponding characteristics limits for the measurement were calculated on the basis of a real example of spectrometric measurement of the activity of uranium radionuclides in a sample. Conclusion: Ensuring the fulfillment of the sufficiency criterion when measuring the activity of uranium radionuclides in biological samples is achieved by the correct determination of the sample measurement time. This is determined by time dependence analysis of the characteristics limits (the decision threshold and the detection limit ) for the measurement of the total activity of the above alpha-emitting uranium radionuclides 234U, 235U and 238U.
Keywords:
individual monitoring programme, alpha spectrometry, sufficiency criterion, decision threshold, detection limit, confidence interval
individual monitoring programme, alpha spectrometry, sufficiency criterion, decision threshold, detection limit, confidence interval
1. Normy radiacionnoy bezopasnosti NRB-99/2009. Gigieni¬cheskie normativy SP 2.6.1.2523-09. M. 2009. 100 s.
2. MU 2.6.1.065-14. Dozimetricheskiy kontrol' professional'nogo vnutrennego oblucheniya. Obschie trebovaniya.
3. Molokanov A.A., Kuhta B.A. Razvitie sistemy kontrolya vnutrennego oblucheniya personala - ispol'zovanie sovremennyh tehnologiy // ANRI. 2018. № 4. S. 2-14.
4. ISO 11929:2010(E). Determination of the Characteristic Limits (Decision Threshold, Detection Limit and Limits of the Confidence Interval) for Measurements of Ionizing Radiation - Fundamentals and Application. Geneva. 2010.
5. ISO/IEC Guide 98-3:2008(E). Guide to the Expression of Uncertainty in Measurements (GUM:1995) // Uncertainty of measurement. Geneva. Switzerland. 2008.
6. GOST 34100.3-2017/ ISO/IEC Guide 98-3:2008 // Neopredelennost' izmereniya. Chast' 3. / Rukovodstvo po vyrazheniyu neopredelennosti izmereniy. Moskva. Standartinform. 2018.
