标题：Spatial distribution of gamma radiation dose rates from natural radionuclides and its radiological hazards in sediments along river Iju, Ogun state Nigeria
摘要：Highlights•Radioactivity in soil sediments of Iju River was found to be within the limit level.•Excess lifetime cancer risks on human and ecosystem found to be higher slightly in some sites.•Activity utilization index from gamma radiation of natural radionuclides found to be within the permissible level.AbstractThis 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 × 10−2for excess lifetime cancer risk (ELCR) for the samples collected in site 6, which is higher than the average world value of 0.29 × 10−3by 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.Graphical absrtactThe Graphical Abstract of the Radionuclides Exposure to the Public living in Different Communities along Iju RiverDisplay Omitted
关键词：Soil sediment;Iju River;Gamma spectroscopy;Radioactivity;Radiological parameters;Excess lifetime cancer risks, Multivariat analysis
