²¹⁰Po, ²¹⁰Pb, ²²⁶Ra, ²³²Th, ⁴⁰K and ¹³⁷Cs Concentration of Medicinal Herbs

Abstract

The ²¹⁰Po, ²¹⁰Pb, ²²⁶Ra, ²³²Th, ⁴⁰K and ¹³⁷Cs activity concentrations were measured related to dry material of ten types of medicinal herbs factory packaged for making tea. For ²¹⁰Po measurement alpha-spectrometry was applied, while the rest of the radionuclides were determined by gammaspectrometry method. In case of ²¹⁰Po the highest activity concentration (10-19 Bq/kg) was measured in herbs consisting of only leaves, while the lowest activity concentration ( ≤ 2 Bq/kg) was measured in medicinal herbs consisting of solely flowers and for ²¹⁰Pb similar trend was found. For the rest of the radionuclides of natural origin the relation was not so obvious. In case of ¹³⁷Cs, the measured values were lower (0.4-1.6 Bq/kg) in cultivated medicinal herbs, than in case of wild grown samples (0.4-20 Bq/kg).