Measurements of natural radioactivity levels and associated radiation hazard indices in Moringa plant leaf samples from selected areas in southern Ethiopia

Moringa stenopetala (MS) is a multipurpose tree whose leaf is consumed by people of all ages in southern Ethiopia. In this study, natural radioactivity levels of 226Ra, 232Th, and 40K, as well as the related dangerous radiological characteristics, were measured on different sites of moringa samples using high-purity germanium (HPGe) gamma-ray spectrometry. Average activity concentrations of 226Ra, 232Th, and 40K in moringa leaves are found to be 0.49 ± 0.12, 3.84 ± 1.12, and 573.29 ± 26.79 Bq.kg-1, respectively. Moreover, the average values of the corresponding radiological parameters, Raeq, Hint, and annual effective dose (Eave) (sum), were also found to be 50.13 ± 3.79 Bq.kg-1, 0.136 ± 0.010, and 0.238 ± 0.089 mSvy-1, respectively. When the obtained results for all of the samples were compared to globally accepted criteria, they were discovered to be lower than the allowable world average levels. Furthermore, the lifetime cancer risk was revealed to be far lower than the allowable limit. According to the study, the risk of absorbing natural radionuclides from moringa leaf ingestion is insignificant. The findings can be utilized to create radiation safety norms and regulations for the use of moringa leaves as food and medication.