Measurement of Radioactivity Concentration in Pegmatite Rock Samples and Dose Assessment from Wamba in North Central Nigeria

Abstract

Aims: To evaluate the radiological impact parameters on mine workers. Study Design: The research work was carried out by using a gamma–ray spectrometer with a NaI (TI) detector. Place and Duration of Study: Centre for Energy and Research Development (CERD), Obafemi Awolowo University, Ile- Ife, Osun State, Nigeria between September 2016 and June 2017. Methodology: The activity concentrations of 226Ra, 232Th, and 40K were determined in ten samples which were used to evaluate the absorbed dose rate, radium equivalent activity, external and internal hazard indices, representative level index, and annual effective dose equivalent. Results: The average activity concentrations of 226Ra (24068.11, 232Th (387.72 , 40K (9509.24) and absorbed dose rate (11720.77) were higher than their respective recommended world mean values of 35 , 45 , 420  and 59  by UNSCEAR. The mean values of radium equivalent activity, external hazard index (Hex), internal hazard index (Hin), representative level index, and annual effective dose equivalent of the area under study were determined as 25346.82, 68.52, 135.43, 357.95, and 14374.36 respectively. This study revealed that all the radiological parameters were higher than their respective recommended world average values. Conclusion: With the high concentrations obtained in this study, it is therefore concluded that this may pose a serious health risk to the miners and the general public. It is therefore advised that necessary guidelines should be provided for the exploration of minerals in this mining site.