Determination of Radon and Thoron Concentrations in Different Parts of Some Plants Used in Traditional Medicine Using Nuclear Track Detectors

摘要

The paper presents results of radon (222Rn) and thoron (220Rn) levels in different parts of some selected plants used in Moroccan cooking and traditional medicine. Plant uptake of radionuclide is one of many vectors for introduction of contaminants into the human food chain. Thus, it is critical to understand the soil–plant relationships that control nuclide bioavailability. The radon and thoron concentrations have been determined in the studied samples and their corresponding soils, and that using the technique based on two types of solid state nuclear track detectors (SSNTDs) LR-115 type-II and CR-39. Transfer factors (TF) of 222Rn and 220Rn from soil to parts of various studied plants have been determined. TF for roots were higher than those for stems and leaves. The radon and thoron activities in the soils have been found varying from 0.87 0.06Bq.kg-1 to 6.20 0.47Bq.kg-1 and from 30 2.30mBq.kg-1 to 195±16mBq.kg-1, respectively. These values are lower in the leaves and stems than those determined in the roots of the studied plants. The aim of this study was to analyze the radon transfer from soil to different compartments of these plants and then to evaluate the radiotoxicity caused by radon in order to contribute to the health risk assessment.