Determination of Natural Radioactivity Levels and Radiation Hazards from the Soil of Tin Mining in Kyerwa District, Tanzania

Mikidadi S. Gurisha *

Tanzania Atomic Energy Commission (TAEC), P.O. Box-743, Arusha, Tanzania.

Atumain A. Makoba

Tanzania Atomic Energy Commission (TAEC), P.O. Box-743, Arusha, Tanzania.

Hellen E. Kiyengo

Tanzania Atomic Energy Commission (TAEC), P.O. Box-743, Arusha, Tanzania.

P.V. Kanaka Rao

Department of Physics, College of Natural and Mathematical Sciences, University of Dodoma P. O. Box-338 Dodoma, Tanzania.

*Author to whom correspondence should be addressed.


Abstract

Gamma spectrometry was used to determine the activity concentrations of the natural radionuclides 226Ra, 232Th, and 40K in soil samples from the Tin mining in Kyerwa District, Tanzania. The study findings revealed that the mean activity concentrations of 226Ra, 232Th, and 40K were 90.68, 65.45, and 630.95 Bq/kg, respectively. These values were all greater than the average global activity concentrations for 226Ra, 232Th, and 40K which are 32 Bq/kg, 45 Bq/kg, and 420 Bq/kg, respectively. Assessments of the radiological risks associated with these naturally occurring radionuclides were done. In this case, the radium equivalent activity (Raeq), external hazard index (Hex), internal hazard index (Hin), and radioactivity level index (Iγ) were calculated. The results show that the mean values of Raeq, Hex, Hin, and Iγ were 230.6 Bq/kg, 0.628, 0.861, and 0.831, respectively. These results were below the global criteria levels for Raeq, Hex, Hin, and Iγ, which are 370 Bq/kg, 1, 1, and 2, respectively. Estimates for the absorbed dose rate in the air (DR), the annual effective dose equivalent (AEDE), and the annual gonadal equivalent dose (AGED) were also made. The findings revealed that the corresponding mean values for DR, AEDE, and AGED were 106.8 nGy/h, 1.07 mSv/y, and 744.4 μSvy-1. The mean values exceeded the global average value of 57 nGy/h for DR, 0.07 mSv/y for AEDE, and 2984 Sv/y for AGED. Therefore, Tin mining activities in the Kyerwa District could endanger the mining community from natural radioactive sources. In this study, therefore, we recommend performing a periodic inspection of the mining areas, monitoring the mining workers, and determining the level of activity and concentrations of different radionuclides in the mining area.

Keywords: Natural radioactivity levels, activity concentration, radiation hazards, radionuclides


How to Cite

Gurisha, Mikidadi S., Atumain A. Makoba, Hellen E. Kiyengo, and P.V. Kanaka Rao. 2024. “Determination of Natural Radioactivity Levels and Radiation Hazards from the Soil of Tin Mining in Kyerwa District, Tanzania”. Physical Science International Journal 28 (4):119-29. https://doi.org/10.9734/psij/2024/v28i4842.

Downloads

Download data is not yet available.