Radioactivity and concomitant radiation dose from Malaysian herbal plants

Abstract

Medicinal plants have been widely used in traditional treatment systems, food supplements, herbal remedies, and cultural practices. Medicinal plants uptake nutrients and radionuclides distributed in the environment and finally transfer them to the human body via various pathways, including plants-to-foodstuffs. It is important to assess the probable radiological impact of medicinal plants consumed for their therapeutic potential in Malaysia. In this study, for the first time, naturally occurring and artificial radionuclides in 14 different medicinal plants in Malaysia are quantified using HPGe gamma-ray spectrometry. The average specific activities for 226Ra, 228Ra, and 40K are found to be 5.42 ± 1.37, 3.81 ± 0.90, and 340 ± 13 Bq kg−1, respectively. The activity concentration of 137Cs is found to be 0.70 ± 0.18 Bq kg−1 only in the star anise sample. The estimated values have been compared with other reported data worldwide as well as the international advisory limits. All activity values are lower than the global average values compared. The values of the annual effective dose and associated excess lifetime cancer risk are lower than the acceptable limits prescribed by the United Nations Scientific Committee on the Effects of Atomic Radiation. Thus, consuming the evaluated herbal plants, which are considered radiologically safe for adult consumption, has no radiological impact. Future research on the radiological safety of human health obtained from medicinal plants and herbs may benefit from the baseline data provided by this study on the radioactivity in medicinal plants.