Assessment of Background and Soil Dumpsites Radioactivity in Plateau State, Nigeria

Abstract

Assessment of background and dumpsites radioactivity level plays a significant role in the protection of man from excessive radiation exposure. Exposure to high radiation levels causes a wide range of health problems such as cancer of the lung, bone and skin, kidney ailments and blood infections. The background radiation levels of 51 selected dumpsites (3 in each LGA) were obtained at 1m above it using a well-calibrated International Medcom CRM-100 Digital Radiation Monitor. Soil samples were also collected, packed, prepared and analysed with Gamma ray Spectrometer [NaI (Tl) detector]. The mean activity concentrations of 226Ra, 232Th and 40K in this study are 61.93±5.90Bq kg-1,123.37±34.05 Bq kg-1 and 276.54±62.44 Bq kg-1 respectively. The mean absorbed dose, AEDE (outdoor) and ELCR in the state have the value of 111 nGyh-1, 0.13 mSv/hr and 0.45 x 10-3 respectively, which are greater than the world average value of 58 nGy h-1, 0.07 mSv/hr and 0.29 x 10-3 respectively. The mean background radiation of the dumpsites recorded in Plateau State was 204 nGy h-1 with the outdoor AEDE of 0.25 mSv/yr and ELCR of 0.88 x 10-3 . These values are greater than the world average. The results obtained for the background radiation are higher than those from the radionuclides analysis. The study revealed that the health risks associated with the radionuclide concentrations of soil dumpsites and the background radiation are relatively high, and the use of dumps as manure and other re-cycling processes therefore raises radiological concern.