Abstract:
This study is conducted for natural radioactivity of some cow organs and fish tissues consumed by the populace of Akure, Ondo State in South-western Nigeria using a Hyper-Pure Germanium (HPGe) detector. The fish and cow organs are analyzed to estimate the activity concentrations of natural radionuclides (238U, 232Th and 40K). A total of 60 samples were collected, ten (10) organs from each of three (3) different cattle (henceforth identified as Cow 1, Cow 2, Cow 3) and three (3) samples per fish specie (henceforth identified as Fish samples 1, 2, 3) of ten (10) different species of fish. The obtained results show that the activities of 40K was highest in all cow organs and fish species considered, followed by concentrations of 232Th and 238U. The mean activity concentrations in all the cow organs considered showed that 238U is highest in Kidney and Heart with 2.82 ± 0.47 and 2.82 ± 0.42 Bq kg-1 respectively and lowest in Small Intestine with 1.14 ± 0.16 Bq kg-1, 232Th is highest in Heart with 4.57 ± 0.69 Bq kg-1 and lowest in Small Intestine with 0.89 ± 0.08 Bq kg-1. 40K is highest in the Heart with 52.07 ± 7.81 Bq kg-1 and lowest in Beef (Muscle) with 17.61 ± 2.14 Bq kg-1. The mean activity concentrations of in the fish tissues considered showed that 238U is highest in Clarias gariepinus (Catfish) with 5.31 ± 1.30 Bq kg-1 and lowest in Scomberomorus tritor (Titus) with 1.51 ± 2.08 Bq kg-1, 232Th is highest in Clarias gariepinus (Catfish) with 6.09 ± 0.91 Bq kg-1 and lowest in Micropogonias undulates (Croaker) with 2.44 ± 0.32 Bq kg-1and 40K is highest in the Micropogonias undulates (Croaker) with 64.42 ± 6.33 Bq kg-1 and lowest in Oreochrornis niloticus (Tilapia) with 6.53 ± 0.98 Bq kg-1. The mean internal hazard index (mSv y-1) ranged from 0.01 to 0.04 in all the cow organs and 0.03 to 0.06 in all the fish tissues which are less than the acceptable limit of 1 mSv y-1. The work shows that consumers of fish and cow organs in Akure have no risk of radioactivity ingestion, even though no amount of radiation is assumed to be totally safe.
