Radioactivity in the Soils of Akoko Area of Ondo State Southwestern Nigeria

摘要

The average concentration of the radioactivity in soil of Akoko area of Ondo State Nigeria, 20years after Chernobyl nuclear power plant accident have been, measured by means of a well-calibrated high-purity germanium detector. The photo-peaks observed with reliable regularity belonged to the naturally occurring series-decay radionuclides headed by 238 U and 232 Th as well as the non-series decay type 40 K. Twenty years after the nuclear accident, 137 CS was detected in all the sampled areas of Ondo State, with an average of 1.12±0.38 Bq kg -1 , the time interval being two-third the 137 Cs half life (30.2years). The mean activity concentration values of 39.24±1.12, 52.86±1.40 and 445.02±12.24 Bq kg -1 for 238 U, 232 Th and 40 K respectively were obtained for the state.