Radionuclides and heavy metals in soil, vegetables and medicinal plants in suburban areas of the cities of Belgrade and Pancevo, Serbia

The content of radionuclides (40K, 238U, 226Ra, 232Th, and 137Cs) and heavy metals (As, Cd, Cu, and Pb) was determined in samples of soil, vegetables and medicinal plants collected in the period 2007-2017, from two suburban areas of Belgrade ? the municipalities of Palilula and Surcin, and Pancevo ? the 'Dr Josif Pancic' Institute for the Study of Medicinal Herbs. During the research period, activity concentration of 137Cs in soil decreased from 16 Bqkg?1 to 3.9 Bqkg?1 (Palilula, Belgrade) and from 18 Bqkg?1 to 12 Bqkg?1 (Surcin, Belgrade). Mean activity concentrations of natural radionuclides in the soil were higher than the global aver- age. Trend for heavy metal levels, according to the average concentrations found in the soil, were as follows: Cu >Pb >As >Cd for Palilula, Pb >Cu >As >Cd for Surcin and Dr Josif Pancic' Institute, Pancevo. The obtained results indicate that the industrial pollution has no impact on food production in the study area and that the main anthropogenic source of radionuclides and heavy metals in soil are mineral phosphorous fertilizers, often used in agricultural fields.