Determination of Activity Concentrations and Soil to Cassava Transfer Factors of Natural Radionuclides in Ikot Ekpene Local Government Area, Akwa Ibom State, Nigeria

Abstract

Natural radioactivity exists in primordial formations such as rocks, soils, water and air where long lived radionuclides such as , , and their affiliates are found. This work was done to determine the specific activity of radionuclides, soil to cassava transfer factor and the effective dose due to consumption of radionuclide in cassava products in Ikot Ekpene Local Government Area, Akwa Ibom State. The specific activity of 40K, 238U and 232Th in soils and cassava in the study area was measured using gamma spectrometry. Mean specific activity in soils ranged from BDL to 153.46 ± 10. 99 Bq/Kg for 40K; BDL to 31. 22 ± 7.49 Bq/Kg for 238U and 1.03 ± 0.10 to 12.71 ± 1.24 Bq/Kg for 232Th. Mean specific activity of the radionuclides in cassava in all locations ranged from 119.86 ± 8.61 to 601.28 ± 43.23 Bq//Kg for 40K; below detectable limit (BDL) to 15. 89 ± 1.55 Bg/Kg for 238U and BDL to 15. 89 ± 1.55 Bq/kg for 232Th. Transfer factors ranged between 3.64 to 4.18 for 40K; 1.30 to 1.82 for 238U and 0.51 to 0.72 for 232Th. Effective ingestion dose due to the consumption of cassava from the area ranged between 0.99 mSv/yr to 1.08 mSv/yr and 2.68 mSv/yr to 29.16 mSv/yr for children and adult respectively. Most of the TF and effective ingestion dose results for this study were above the recommended value of unity which suggests that consumption of cassava from the studied area may pose radiological health.

"Radioactivity Concentration and Radionuclide Transfer Factor Assessment in Afang Leaves (Gnetum africanum) Cultivated in Akwa Ibom State, Nigeria"

“…Figure 2 shows the distribution of the mean transfer factors of radionuclides from soil to afang samples from the study areas. From Figure 2 it is observed that AC and TF for afang in this work are also lower compared to that obtained for fluted pumpkin leaves [13]. This may be due to high mineral content of afang leaves, giving it a low chance to accept a high amount of radionuclides [11].…”

Measurement of transfer factors from soil-to-plant/food crop of Naturally Occurring Radionuclide Materials (NORMs) in Nigeria: a review

“…al., 2021); for 228 Ra, 18.0 BqKg -1 (Ademola, 2019); for 238 U, it was 5.98 BqKg -1 (Oluyide et. al., 2018) while 1.03 BqKg -1 was recorded for 232 Th (Essien et. al., 2021).…”

“…The values of annual ingestion effective doses exhibited by the crops are higher than the world average value of 70 µSv.y -1 while the excess lifetime cancer risks were also higher than that of the world average limit of 1.0 x 10 -3 . Essien et. al., (2021) determined the activity concentrations and soil-to-plant transfer factors of natural radionuclides in Ikot Ekpene Local Government Area, Akwa Ibom State, Nigeria using gamma spectrometry analytical method with [NaI(Tl)] scintillation detector.…”

Activity concentration, transfer factor and radiological health risk assessment of natural radionuclides in soil and maize in oil producing areas in Akwa Ibom state, Nigeria

“…The estimation of the radioactivity concentration of the radionuclides per unit mass may be carried out using the Equation 1 (Essien et al, 2021;Eyibio et al, 2023).…”