TY - JOUR T1 - Evaluation of Radiological Hazard Indices of Oniru Beach, Lagos, Nigeria Using Measurements of Natural Radionuclides 238U, 232Th and 40K TT - Evaluation of Radiological Hazard Indices of Oniru Beach, Lagos, Nigeria Using Measurements of Natural Radionuclides 238U, 232Th and 40K AU - Asifat, Adeniji Moradeyo AU - Adeniyi, Adewoyin Kehinde AU - Atanda, Jimoh Rafiu PY - 2026 DA - February Y2 - 2026 DO - 10.59474/nuclear.2023.66 JF - Journal of Nuclear Sciences PB - Ankara University WT - DergiPark SN - 2147-7736 VL - 10 IS - 1 LA - en AB - This study assesses the radiological risks associated with naturally occurring radionuclides ²³⁸U, ²³²Th, and ⁴⁰K present in the sands of Oniru Beach, situated in Lagos, Nigeria. These radionuclides, naturally present in geological materials, can pose health hazards when found in elevated concentrations, especially in areas with regular human activity such as recreational beaches. Gamma-ray spectrometry was employed to measure the activity concentrations of ⁴⁰K, ²³⁸U, and ²³²Th in sand samples collected from multiple points along the beach. The mean activity concentrations recorded were 10.85 Bq·kg⁻¹ for ²³⁸U, 9.25 Bq·kg⁻¹ for ²³²Th, and 265 Bq·kg⁻¹ for ⁴⁰K. The potential radiological impacts of these concentrations were evaluated to determine their hazard indices. These include the radium equivalent activity (Raeq), estimated at 44.5 Bq·kg⁻¹, the external hazard index (Hex) of 0.120, and the internal hazard index (Hin) of 0.149. The absorbed dose rate (D) of 21.66 nGy∙h-1; the annual effective dose equivalent (AEDE) of 0.0266 mSv/y; and the excess lifetime cancer risk (ELCR) estimated at 9.30×10⁻². When compared with internationally recognized safety thresholds, such as those set by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), all the calculated indices fall well below recommended limits. This suggests that exposure to sand at Oniru Beach does not present any significant radiological hazard to public health. KW - Radiological hazards KW - Oniru beach KW - Natural radionuclides KW - Hazard indices KW - Environmental safety. N2 - This study assesses the radiological risks associated with naturally occurring radionuclides ²³⁸U, ²³²Th, and ⁴⁰K present in the sands of Oniru Beach, situated in Lagos, Nigeria. These radionuclides, naturally present in geological materials, can pose health hazards when found in elevated concentrations, especially in areas with regular human activity such as recreational beaches. Gamma-ray spectrometry was employed to measure the activity concentrations of ⁴⁰K, ²³⁸U, and ²³²Th in sand samples collected from multiple points along the beach. The mean activity concentrations recorded were 10.85 Bq·kg⁻¹ for ²³⁸U, 9.25 Bq·kg⁻¹ for ²³²Th, and 265 Bq·kg⁻¹ for ⁴⁰K. The potential radiological impacts of these concentrations were evaluated to determine their hazard indices. These include the radium equivalent activity (Raeq), estimated at 44.5 Bq·kg⁻¹, the external hazard index (Hex) of 0.120, and the internal hazard index (Hin) of 0.149. The absorbed dose rate (D) of 21.66 nGy∙h-1; the annual effective dose equivalent (AEDE) of 0.0266 mSv/y; and the excess lifetime cancer risk (ELCR) estimated at 9.30×10⁻². When compared with internationally recognized safety thresholds, such as those set by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), all the calculated indices fall well below recommended limits. This suggests that exposure to sand at Oniru Beach does not present any significant radiological hazard to public health. CR - [1] United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Sources and effects of ionizing radiation: Report to the General Assembly with scientific annexes. United Nations (2000). CR - [2] International Atomic Energy Agency (IAEA). Naturally Occurring Radioactive Material (NORM IV). IAEA Proceedings Series (2018). [3] Rasheed, A. A., Kadhum, N. F., and Ibrahim, N. K., “Natural Radioactivity and Associated Dose Rates in Soil Samples in the Destroyed Fuel Fabrication Facility, Iraq”, International Journal of Physics, 4(3), 50-54 (2016). CR - [4] Jimoh, R. A., Bankole, O. M., Ahmed, K, et al., “Use of geophysical logs in hydrogeological studies and borehole designs: case study of Apapa coastal area, Lagos, Nigeria”, Applied Water Science by Springer 8, 191 (2018). CR - [5] Alzubaidi, G., Hamid, F. B, and Abdul Rahman, I., “Assessment of Natural Radioactivity Levels and Radiation Hazards in Agricultural and Virgin Soil in the State of Kedah, North of Malaysia”, Scientific World Journal 6178103 (2016). CR - [6] United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), Sources and Effects of Ionizing Radiation in United Nations Scientific Committee on the Effects of Atomic Radiation, New York: United Nation Publication (2008). CR - [7] Saglam, F., and Cetin, B., “Investigation of Gamma Shielding Properties of Some Industrial Materials", International Journal of Computational and Experimental Science and Engineering, 11(2) (2025). CR - [8] Omeje, M., Adewoyin, O. O., Joel, E. S. et al., “Spatial distribution of gamma radiation dose rates from natural radionuclides and its radiological hazards in sediments along river Iju, Ogun state Nigeria”. MethodsX 7(7), 101086 (2020). CR - [9] Ademola, J. A., and Nwafor, C. O, “Radiological risk assessment of natural radionuclides in sand collected from some beaches along the coastline of Southwestern Nigeria”, Radiation Protection Dosimetry, 156(4), 458-464 (2013) CR - [10] Oghenevovwero, E. E., Avwiri, G. O., Sylvanus, O. A., and Onwudiwe, D. C., “Radiometric survey of sediments and health risk assessments from the southern coastal area of Delta State, Nigeria”, Heliyon 21;10(5): e26805 (2024). CR - [11] Ibikunle, S. B., Arogunjo, A. M., and O. S. Ajayi, “Characterization of radiation dose and excess lifetime cancer risk due to natural radionuclides in soils from some cities in Southwestern Nigeria”, Journal of Forensic Sciences and Criminal Investigation, 10(4), 555793 (2018). CR - [12] Eke, B. C., Akomolafe, I. R., Ukewuihe, U. M., and Onyenegecha, C. P, “Assessment of radiation hazard indices due to natural radionuclides in soil samples from Imo State University, Owerri, Nigeria”, Environmental Health Insights, 18, 1–14 (2024). CR - [13] Avwiri, G. O., Enyinna P. I., and Agbalagba, E. O. “Terrestrial Radiation Around Oil And Gas Facilities in Ughelli Nigeria”, Journal of Applied Sciences, 7 1543-1546 (2007). CR - [14] Jibiri, N. N., and Farai, I. P., “Assessment of Dose Rate and Collective Effective Dose Equivalent Due to Terrestrial Gamma Radiation in the City of Lagos, Nigeria”, Radiation Protection Dosimetry, 76(3), 191-194, (1998). CR - [15] Farideh, A. M., Farid, M., Faghihi, R., and Keshavarz, B, “Distribution of natural radionuclides and assessment of the associated radiological hazards in the rock and soil samples from a high-level natural radiation area, Northern Iran”, Journal of Radioanalytical and Nuclear Chemistry 322(2), (2019) DOI: 10.1007/s10967-019-06912-z CR - [16] David, O. J., Afolabi, T. A., Agunbiade, F. O., Afolabi, T. A., Ogundiran, O. O., Gbadamosi, M. R., et al., “Spatial distribution and radiological hazards assessment of naturally occurring radionuclide materials in soil from quarry sites in Ogun State, Nigeria”, Environ Monit Assess 197:575 (2025). CR - [17] Joel, E.S., Maxwell, O., Adewoyin, O.O., Olawole, O. C., et al., “Investigation of natural environmental radioactivity concentration in soil of coastaline area of Ado-Odo/Ota Nigeria and its radiological implications”, Sci Rep 9, 4219 (2019). CR - [18] Joel, E. S., Omeje, M., Olawole, O. C., Adeyemi, G. A., Akinpelu, A., Embong, Z., and Saeed, M. A., “In-situ assessment of natural terrestrial-radioactivity from Uranium-238 (238U), Thorium-232 (232Th) and Potassium-40 (40K) in coastal urban-environment and its possible health implication”, Sci Rep 11, 17555 (2021). UR - https://doi.org/10.59474/nuclear.2023.66 L1 - https://dergipark.org.tr/en/download/article-file/5443467 ER -