Study of Accumulation of Natural and Artificial Radioisotopes by Medicinal Plant Raw Materials on the Example of Plantain Leaves of Large Flora of Urbanized Territories of the Central Black Earth Region

Objective: The purpose of this study was to investigate the accumulation of natural and artificial radioisotopes in medicinal plant raw materials, specifically examining greater plantain (Plantago major L.) leaves harvested from various territories of the Voronezh region, which differ in anthropogenic impact. Methods: The specific activity of long-lived artificial radionuclides (cesium-137, strontium-90) and natural radionuclides (thorium-232, potassium-40, radium-226) was measured in soil and greater plantain leaves using an MKGB-01 RADEK spectrometer-radiometer. Samples were collected from diverse areas with varying levels of industrial, agricultural, and urban influences. Correlation analysis and accumulation coefficients were used to assess the transfer of radionuclides from soil to plant. Results and Discussion: The results indicated that all collected greater plantain samples complied with radiation safety standards. Cesium-137 and strontium-90 were present in higher concentrations than natural radionuclides, but all levels were within permissible limits. A strong correlation between the radionuclide content in soil and plant leaves was observed, confirming that the contamination primarily occurs through soil. Accumulation coefficients for cesium-137 ranged from 1.81 to 3.29, with an average of 2.55. The study also identified trends of decreased accumulation with increased radionuclide concentrations in the soil, suggesting physiological mechanisms regulating radionuclide uptake. Conclusions: Greater plantain leaves from the Voronezh region accumulate radionuclides primarily through soil contamination. The study confirms that the leaves meet radiation safety standards for medicinal plant raw materials. Accumulation of cesium-137 was notably high, while other radionuclides showed lower levels. The results highlight the importance of monitoring radionuclide contamination in medicinal plants, particularly in urbanized and industrialized areas.