EVALUATION OF RADIOLOGICAL HAZARD INDICES AND EXCESS LIFETIME CANCER RISK ASSOCIATED WITH THE USE OF OGUN RIVER SEDIMENT AS BUILDING MATERIAL

Abstract

The radioactivity concentrations of ⁴⁰K, ²³⁸U and ²³²Th in sediment samples of Ogun river at Abeokuta, Ogun State in Nigeria were evaluated by gamma spectrometry using NaI (TI) detector coupled with a pre-amplifier base to a multiple channel analyzer (MCA), these were then used to determine the radiological indicators; radium equivalent activity, internal and external hazard indices, and absorbed dose rate which translated to the annual effective dose rate. 10 sediment samples were collected from the river. The values of the radiological indicators and excess lifetime cancer risk were found to be within the limits recommended, indicating that the use of the sediment of the river as building material does not have radiological health hazards to the occupants of the buildings.