CHARACTERISTICS OF RADIONUCLIDE ACCUMULATION IN DANDELION ROOTS IN THE CENTRAL BLACK EARTH REGION

The aim of the study is to examine accumulation patterns of natural and man-made radioactive isotopes in dandelion roots (Taraxacum officinale F.H. Wigg.), harvested in different areas of the Voronezh region. Materials and Methods. Under experiment, the specific activity of the main long-lived artificial radioisotopes (cesium-137, strontium-90) and naturally occurring radionuclides (thorium-232, potassium-40, radium-226) was determined in the samples of top soil and dandelion roots using a MKGB-01 RADEK spectrometer-radiometer. Results. All the studied samples of dandelion roots conform to the existing radiation safety requirements (first group). With the increase in the specific activity of strontium-90, cesium-137, thorium-232, potassium-40, and radium-226 in the soil, their specific activity in plant roots also increased. Correlation analysis of the specific activity of man-made and natural radionuclides in the soil and roots demonstrated a very noticeable correlation, which confirmed the predominant trans-soil root contamination. The calculated accumulation factors of radionuclides in dandelion roots showed fast accumulation of strontium-90 and radium-226 from soils. The specific activity of these radioisotopes in medicinal plant raw materials was significantly higher than that in soil. A detailed analysis of the dependence of the calculated accumulation coefficients of natural and man-made radioisotopes in dandelion roots allowed us to note the tendencies towards their decrease with an increase in the specific activity of the radionuclide in soil. This fact indicates the existence of physiological mechanisms regulating their accumulation in plant roots. The transition patterns of the studied natural and man-made radionuclides are described by mathematical dependencies with the maximum coefficient of approximation reliability.