International Journal of
Physical Sciences

  • Abbreviation: Int. J. Phys. Sci.
  • Language: English
  • ISSN: 1992-1950
  • DOI: 10.5897/IJPS
  • Start Year: 2006
  • Published Articles: 2503

Article in Press

ESTIMATION OF RADIOLOGICAL PARAMETERS ASSOCIATED WITH MINING OF TANTALITE IN OKE-OGUN, OYO STATE, NIGERIA

ABAYOMI EKUNDAYO AJETUNMOBI

  •  Received: 25 July 2018
  •  Accepted: 29 January 2019
Mining activities brings the artisan miners to close proximity with naturally occurring radioactive materials (NORM) which exposes the miners to ionizing radiation. In this study, estimation of radiological hazards and risks related to work activities in Tantalite mining sites in Oke-Ogun, Oyo State has been carried out. A total 40 samples comprising of (12) Tantalite ore ({Fe,Mn}Ta206), 17 soil samples and 11 waste rocks samples were randomly selected. 200mg of each sample were pulverized to 2.0mm grain size, sealed in a cylindrical container and kept for 28 days to achieve equilibrium between 226Ra and its decay product for activity concentration measurement of 226Ra, 238U, 232Th and 40K using Hyper Pure Germanium Gamma spectrometer. Cancer and hereditary risk were estimated using ICRP cancer risk assessment methodology. Radiological parameters for the study were estimated using appropriate convectional equations. The ranges of activity concentrations (Bq/kg) of 226Ra, 238U, 232Th and 40K were 18000 - 114000, 11600 - 95000, 1400 - 2800 and 50 - 745 respectively. The fatal cancer risk per year 1.10E-05 ̶ 9.90E-07. Life time cancer risk falls within 0.06-3.8 while the severe hereditary effect per year falls within 5.0E-08 ̶ 8.05E-07. Absorbed dose rates for the study are within the range of 6 ̶ 256 nGy/hr and annual effective dose rates are within 0.01-0.5 mSv/yr. External, internal and Gamma indexes are within the Range of 0.07-2.7. Radium Equivalent falls within 32-256. The gonad dose equivalent falls within 120 ̶ 1731µSv/yr and the activity utilization indexes falls within 0.5-17. The study showed that the radiological parameters estimated for some of the samples are not beyond permissible limits and may be of detrimental health effect for the miners, hence appropriate measures to reduce the exposure of the miners such as use of appropriate shielding materials that reduces are strongly recommended.