Seasonal Variation in the Concentrations of Radionuclides and Radiological Health Assessment of Some Tin Mining Areas of Barkin Ladi Lga of Plateau State Nigeria

Radionuclides are found not only in the earth's crust but also in all of its environments, including soil, water, and the atmosphere. This is as a result of naturally occurring radioactive series of 238 U and 232 Th. Barkin Ladi Local Government Area is located in the heart of Northern Nigeria and is distinguished by its rough, low terrain. This area serves as the focal point for younger granites and is the primary center of tin and columbite mineralization. Samples were taken in February and July and examined with a gamma-ray spectrometer to evaluate seasonal variation in radionuclide concentrations. The average ranges of radionuclide concentrations are shown by the results In February: 40 K (209.9957 ± 0.27 to 271.3964 ± 0.54 Bq/kg), 226 Ra (69.3912 ± 0.16 to 98.0745 ± 0.88 Bq/kg), and 232 Th (78.0992 ± 0.86 to 97.4741 ± 0.31 Bq/kg). In July: 40 K (184.7383 ± 0.36 to 208.0652 ± 0.08 Bq/kg), 226 Ra (65.9556 ± 0.40 to 78.4196 ± 0.76 Bq/kg), and 232 Th (75.6379 ± 0.98 to 86.4623 ± 0.94 Bq/kg). The results show a decrease in 40 K and 232 Th concentrations during the wet season compared to the dry season, with an average decrease of 11.40% and 10.30%, respectively. All 40 K results were below the recommended limit of 412 Bq/kg, while 226Ra and 232 Th results exceeded the world averages of 33 Bq/kg and 45 Bq/kg, respectively. The pH, electrical conductivity (EC), and organic carbon (OC) values ranged from: Dry season: pH (4.20 - 5.81), EC (397.07 - 697), and OC (0.69 - 1.21). Wet season: pH (5.55 - 6.42), EC (302.16 - 489), and OC (0.43 - 0.86). Excess lifetime cancer risk (ELCR) values were highest in locations N (4.3 x 10 -4 ) and F (4.2 x 10 -4 ), indicating elevated cancer risk associated with radiation exposure in these areas. In conclusion, the study reveals that the soil samples in the different locations are polluted with radionuclides 226 Ra and 232 Th, particularly during the dry season. The results also suggest that people living in the study area may be at risk of developing cancer due to prolonged radiation exposure. Therefore, it is essential to take measures to mitigate radiation exposure and ensure the radiological safety of the area.