Radiological assessment of commonly food crops in Southwestern Nigeria

Natural radionuclides are present in food items at different levels and are influenced by factors like background radiation, climate, and agricultural practices. These radionuclides play a crucial role in humans' internal radiation exposure. Notably, radionuclides within the decay series ²³⁸U and ²³²Th as well as ⁴⁰K are significant concerns in radiation protection due to their prevalence and potential health risks. The activity concentrations of radionuclides ²³⁸U, ²³²Th, and ⁴⁰K in several food crops consumed within Lagos city in Nigeria were measured using gamma spectrometry. The concentrations of ²³⁸U, ²³²Th, and ⁴⁰K ranged from 0.90 to 55.30, BDL (Below Detection Limit) to 161.60 and 10.30 to 1075.20 Bqkg⁻¹, respectively. The average radionuclide activity concentrations are below the acceptable global level, or the worldwide average values set by the United Nations Scientific Committee on the Effects of Atomic Radiation in 2000 (UNSCEAR, 2000), which are 35, 30, and 400 Bqkg⁻¹ for ²³⁸U, ²³²Th, and ⁴⁰K, respectively. The study calculated the annual effective dose for individuals consuming the studied food items, and the annual internal dose from ingesting was found to be 8.95 × 10^-04 μSvy⁻¹. It’s noteworthy that this computed value is below the worldwide value of 0.32 mSv y⁻¹ set for the public. Additionally, the excess lifetime cancer risk (ELCR) value was 3.13 × 10⁻³ μSvy⁻¹, which is within the world safe limit value (2.9 × 10⁻⁴ μSvy⁻¹). Therefore, there is no potential radiological risk associated with the measured data.