ASSESSMENT OF RADIOLOGICAL HAZARD INDICES OF FARM SOILS IN LAKOWE, IBEJU-LEKKI, NIGERIA: IMPLICATIONS FOR AGRICULTURAL SUSTAINABILITY

Farm soil may contain varying levels of radioactivity with tendency to gain entry into humans directly or via farm crops thereby precipitating hazards to human health. It is, therefore, important to determine the radioactivity contents in farm soil with a view to radiation protection and public health. This article presents the results of radioactivity concentrations of226Ra, 232Th and 40K in the farmland at Lakowe area of Ibeju-lekki, Lagos State, Southwestern Nigeria. Activity concentration measurements of the radionuclides in soil samples were carried out using NaI (TI) detector. Radon concentrations measured in equilibrium with radium yields radium concentration in the samples as falling between 10.10+1.01 and 13.49 ± 2.50 Bq kg-1, while 232Th and 40K ranged between 9.21+0.21 and 12.02+1.02, 102.34+10.01 and 298.76+1.02 Bqkg-1 respectively with the mean activity concentration values; 10.89+1.40, 10.23+0.93 and 187.36+3.06 Bq kg-1 for 226Ra, 232Th and 40K respectively. These values were compared with the recommended safe limits for soil samples by UNSCEAR and found to be lower than the global average values and consequently no radiation induced health risk to those involved in farming activities in the area. In addition, all radiological hazard parameters assessed with the results of analysis of the farm site fell below the world standard specified by UNSCEAR. Therefore the farm produce in the area are free from radiological hazards and safe for human consumption without risk from excess life time cancer risk (ELCR). Hence, exposure to these radionuclides (226Ra, 232T, and 40K) constitutes no health risk to farmers, making farming in the area sustainable.