Naturally Occurring Radionuclides present in some vegetable in Owerri, Imo State, Nigeria

Naturally occurring radionuclide materials are usually absorbed by plants through their root systems as nutrients, which in turn pose a radiation risk to humans when they consume the plants as food. This study evaluated the radionuclide risks from naturally occurring radionuclides in samples of commonly consumed vegetables in Owerri. Gamma ray spectroscopy was used to analyze and profile the 226Ra, 232Th and 40K levels in the vegetable samples of African basil, water leaf, uziza leaf and bitter leaf which are commonly consumed vegetables in Owerri, south-eastern Nigeria. No artificial radionuclides were observed in all the vegetable samples. The 40K level was found to be lower than the permissible level for all the vegetables while values above the permissible levels were observed for 226Ra and 232Th. We subsequently evaluated the Activity concentrations, Absorbed Gamma Dose Rate (DR), Annual Effective Dose Equivalent (AEDE), Excess Lifetime Cancer Risk (ELCR). The range for the activity concentrations were, 193.86 to 391.05 for 40K, 12.54 to 43.07 for 226Ra and 91.92 to 111.27 for 232Th. Although the absorbed dose (DR) was almost twice the world average value, ELCR were lower than the permissible values indicating consumption safety for those who do not rely heavily on the consumption of these common vegetables.