HPGe spectrometry in food safety: characterizing the radiological profile and health risks of antioxidant-rich superfoods

Humans are continuously exposed to natural radiation, including radionuclides such as uranium, thorium, and potassium-40 (40K), which can enter the food chain through soil–plant transfer. With the growing consumption of ‘superfoods’, assessing their radioactive content is increasingly important. In this study, the activity concentrations of 226Ra, 232Th, 40K and 137Cs in antioxidant-rich food samples were measured by using a gamma-ray spectrometer with a high-purity germanium (HPGe) detector. Results showed that radionuclide levels were generally below global averages, except for 40K. The excess lifetime cancer risk (ELCR) for 232Th in chia seeds at maximum daily consumption was 568.30 × 10−6, approximately twice the global average (290 × 10−6). The 137Cs activity concentrations measured in the food samples posed no significant public health risk, with the highest value observed in green tea. Annual effective organ dose calculations revealed that the testis was the most affected organ. Overall, the results underscore the importance of taking into account the accumulation of natural radionuclides in superfoods as food consumption increases.