Spatial distribution of gamma radiation dose rates from natural radionuclides and its radiological hazards in sediments along river Iju, Ogun state Nigeria
Omeje Maxwell,
Adewoyin Olusegun O.,
Joel Emmanuel S.,
Ikechukwu Ijeh B.,
Omeje Uchechukwu A.,
Ayanbisi Oluwasegun,
Iyanuoluwa Ogunrinola E.,
Timothy Terhile Angbiandoo M.,
Oha Ifeany A.,
Mohammad Alam Saeed
Affiliations
Omeje Maxwell
Department of Physics, College of Science and Technology, Covenant University, P.M.B 1023, Ota, Ogun State, Nigeria; Corresponding author.
Adewoyin Olusegun O.
Department of Physics, College of Science and Technology, Covenant University, P.M.B 1023, Ota, Ogun State, Nigeria
Joel Emmanuel S.
Department of Physics, College of Science and Technology, Covenant University, P.M.B 1023, Ota, Ogun State, Nigeria
Ikechukwu Ijeh B.
Department of Physics, Michael Okpara University of Agriculture, Umudike, Umuahia, Abia State
Omeje Uchechukwu A.
Department of Public and Community Health Care, College of Medicine, Idiaraba, University of Lagos, Nigeria
Ayanbisi Oluwasegun
Department of Physics, College of Science and Technology, Covenant University, P.M.B 1023, Ota, Ogun State, Nigeria
Iyanuoluwa Ogunrinola E.
Department of Physics, College of Science and Technology, Covenant University, P.M.B 1023, Ota, Ogun State, Nigeria
Timothy Terhile Angbiandoo M.
Department of Physics, Michael Okpara University of Agriculture, Umudike, Umuahia, Abia State
Oha Ifeany A.
Department of Geology, Faculty of Science, University of Nigeria, Nsukka, Nigeria
Mohammad Alam Saeed
Division of Science and Technology, University of Education Township Lahore-Pakistan, Pakistan
This study assessed the radioactivity level of Iju River sediments and its associated radiological risks exposure to human. Gamma absorbed dose rates were measured using a portable gamma spectrometer at an interval of 50 m between each point (Model No:RS-125 manufactured by Canadian Geophysical Institute). The measured absorbed gamma dose rates range from 22 to 59 nGy/h with the highest value noted in site 13. The mean activity concentrations of U-238, Th-232 and K-40 from Iju river sediments were 24.1 ± 0.4 Bq/kg, 35.2 ± 1.1 Bq/kg and 501.0 ± 11.1 Bq/kg, which were lower than the world average values of 32 and 45 for U-238 and Th-232 by 25% and 21% and higher than 412 Bq/kg for K-40 by a factor of 0.22 (22%). • This highest value of K-40 found in site 6 may be due to the presence of feldspartic minerals buried in the sediments. • Consequently, the radiological hazard indices were below the permissible limits except the mean value of 28 × 10−2 for excess lifetime cancer risk (ELCR) for the samples collected in site 6, which is higher than the average world value of 0.29 × 10−3 by a factor of 0.03. • The regression model indicates that Th-232 attributes more radioactivity impacts on the soil sediments than the contributions of U-232 and K-40, as such, presumed to be the radionuclide parameter controlling the depositional process in the region.
