EVALUATION OF THE POTENTIAL OF THE RADIOMETRIC METHOD IN THE ANALYSIS OF RADIONUCLIDES IN ECOSYSTEM OBJECTS

ABSTRACT

This article examines the capabilities of the radiometric method for determining the quantity of radionuclides in ecosystem objects and presents the analysis results of soil, water, and atmospheric air samples collected from the territories of the Navoi and Samarkand regions. Based on the obtained data, a comparative study was conducted on the graphical dependencies of the equivalent dose rate (EDR) of external gamma radiation, the equivalent value of the equilibrium volumetric activity of radon (EVAR), the effective dose rate of long-lived alpha nuclides (EDR-LLA), and the effective dose rate in drinking water  (EDR-DW).

АННОТАЦИЯ

В данной статье рассматриваются возможности радиометрического метода для определения количества радионуклидов в объектах экосистемы, а также приведены результаты анализа проб почвы, воды и атмосферного воздуха, отобранных с территорий Навоийской и Самаркандской областей. На основе полученных данных проведено сравнительное исследование графических зависимостей мощности эквивалентной дозовой (МЭД) внешнего гамма-излучения, эквивалентного значения равновесной объемной активности радона (ЭРОА), эффективной дозовой мощности долгоживущих альфа-нуклидов (ДАН) и эффективной дозовой мощности, формируемой в питьевой воде (ЭДВО).

Keywords: ecosystem objects, radiometric method, radiation factor, equivalent dose, effective dose, dose rate, activity, radionuclide, gamma radiation.

Ключевые слова: объекты экосистемы, радиометрический метод, радиационный фактор, эквивалентная доза, эффективная доза, мощность дозы, активность, радионуклид, гамма-излучение.

Introduction

Continuous radioecological monitoring and the implementation of radiation mitigation strategies in high-radiation areas, particularly in regions near uranium production facilities, are essential for safeguarding public health [1].

Among the radionuclides in the uranium decay chain, ²³⁴U, ²²⁶Ra, ²²²Rn, ²¹⁸Po, ²¹⁴Bi, and other elements are present, with ²²²Rn (radon gas) being the most hazardous. This is because the decay of ²²²Rn produces radioactive short-lived radionuclides – ²¹⁸Po, ²¹⁴Bi, and ²¹⁰Rb. These short-lived radionuclides often accumulate in aerosols emitted from uranium facilities [2-5].

Key atmospheric radiation factors, including the equivalent dose rate of external gamma radiation (EDR), the equilibrium volumetric activity of radon (EVAR), the effective dose rate of long-lived alpha nuclides (EDR-LLA), and the effective dose rate in drinking water (EDR-DW), have been identified as critical determinants of environmental and public health risks. A comparative analysis of these factors in residential areas is therefore a pressing concern in nuclear physics and radioecology [6-8].

Research methodology

The radiometric method, a rapid and reliable nuclear-physical technique, was employed to assess the radiation status of ecosystem components. Various radiometers were utilized to measure the factors contributing to environmental and public health risks.

In this study, the equivalent dose rate of gamma radiation was measured using the “DKC-96” radiometer, while the equilibrium volumetric activity of radon was determined using the “ALPHARAD PLUS” measurement complex. The effective dose rate of long-lived alpha nuclides was quantified with the “POISK” radiometer, and the effective dose rate in drinking water was assessed using the “UMF-2000” low-background alpha-beta radiometer [2-4; 9, 10].

Results and discussion

Analysis of soil, water, and atmospheric air samples from the Navoi and Samarkand regions revealed the following radiation metrics: the equivalent dose rate of external gamma radiation (EDR), the equilibrium volumetric activity of radon (EVAR), the effective dose rate of long-lived alpha nuclides (EDR-LLA), and the effective dose rate in drinking water (EDR-DW). These results are summarized in Table 1.

Table 1.

Analysis results of soil, water, and atmospheric air samples taken from the territories of Navoi and Samarkand regions

As seen from Table 1, in the samples from the Navoi region, the average equivalent dose rate of external gamma radiation is 0.246 mSv/h, the average equivalent volumetric equilibrium dose rate of radon is 4.19 mSv/h, the average dose rate of long-lived alpha nuclides is 0.245 mSv/h, and the average effective dose rate in drinking water is 0.154 Bq/l.

In the samples from the Samarkand region, these indicators are slightly lower: the average effective dose rate of external gamma radiation is 0.18 mSv/h, the average equivalent volumetric equilibrium dose rate of radon is 3.07 mSv/h, the average dose rate of long-lived alpha nuclides is 0.182 mSv/h, and the average effective dose rate in drinking water is 0.112 Bq/l.

The dose rates detected in the territories of the Navoi and Samarkand regions are presented and compared in graphical form in Figures 1, 2, 3, and 4 below.

From the figures above, it can be observed that the radiation indicators in the Navoi region are higher compared to those in the Samarkand region. In the Navoi region, the effective dose rate of gamma radiation is 26.8% higher, the equivalent volumetric equilibrium dose rate of radon is 26.7% higher, the dose rate of long-lived alpha nuclides is 25.7% higher, and the effective dose rate in drinking water is 27.3% higher than in the Samarkand region.

Conclusion

Based on the comparison of radiation factors - EDR, EVAR, EDR-LLA, and EDR-DW - in the territories of the Navoi and Samarkand regions, radiometric measurement methods were studied, the results obtained at observation points were analyzed, and their graphical representations were created.

According to the results of the conducted studies, the average total values of these factors (EDR + EVAR + EDR_LLA + EDR_DW) were 4.835 mSv/h in the Navoi region and 3.544 mSv/h in the Samarkand region. These values comply with the established standards and do not exceed the limits specified in SanPiN-0193-06 [11, 12].

The obtained data indicate that the radiation situation in these regions is satisfactory and does not have an explicitly negative harmful effect on the population and the environment.

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