Evaluation of radioactivity levels and radiological hazards of some endemic plants used as medicine in Ankara, Turkey

In this study, natural radioactivity levels (226Ra, 232Th, and 4 K) of some medicinal plant samples with known anti-oxidative properties, which are frequently consumed by animals and humans, were obtained from Ankara province and its surroundings (Mamak, Kızılcahamam, Beypazarı, Kahramankazan, and Polatlı districts) were determined using a thallium-doped sodium iodide NaI(Tl) gamma spectrometry. By using the determined natural radioactivity concentrations in the collected plant samples, the number of radiological doses that people could be exposed by consuming these plants was calculated. As a result of the study, 226Ra, 232Th, and 4 K radioactivity concentration ranges of the plant samples were found be 14.69 ± 1.27–59.08 ± 3.12 Bq kg−1, 1.78 ± 0.04–50.05 ± 2.76 Bq kg−1 and 207.24 ± 34.09–826.13 ± 25.40 Bq kg−1, respectively. The highest 226Ra, 232Th, and 4 K activity concentrations were measured in Astragalus densifolius subsp. ayashensis (Kahramankazan), Astragalus kochakii (Kahramankazan) and Rumex patientia (Patience Dock) (Kahramankazan) plants, respectively. The lowest 226Ra, 232Th and,4 K activity concentration plants were determined respectively as Rumex patientia (Mamak), Lavandula angustifolia (Kızılcahamam), and Astragalus acikirensis (Polatlı). The establishment and routine repetition of environmental radioactivity monitoring programs in each region are important for human and animal health, and the results of this study gain importance for Ankara and its surroundings in terms of environmental health. •The activity concentrations of 226Ra, 232Th, and 40 K radioisotope levels were determined in 35 medicinal plant samples taken from Turkey.•Radiological hazard parameters were calculated.•It has been determined that the therapeutic use of these medicinal plants investigated will not pose any health hazards to humans.•These results can provide basic data that may be useful in the development of standards for the use of medicinal plants in the manufacture of medicinal drugs and cosmetic products by relevant organizations.