Human exposure levels to ionizing radiation in Agbara Industrial Estate: an impact of Industrial activities in Nigeria

摘要

A total of fifty-five soil samples were collected from four locations, namely, residential, industrial, dumpsite, and sewage in Agbara industrial estate, Ogun state, Nigeria. The samples were analyzed using a high purity germanium detector (HPGe) to measure the activity concentration of radionuclides. Background radiation measurements were also taken at each point where soil samples were collected using Geiger Muller (GM) counter. The mean activity concentrations measured in the soil samples were 171.33 for K-40, 9.11 for Th-232, and 5.05 for Ra-226 in Bq/kg. The mean absorbed dose rate in the air due to radionuclides (K-40, Th-232, and Ra-226) in the soil is calculated to be 14.77 nGy/h, and the mean annual effective dose equivalent (AEDE) is 0.02 mSv/year. The mean equivalent dose rate (EDR) from GM counter for background radiation is 0.22 mu Sv/h, and the mean annual effective dose rate (AEDR) is 0.39 mSv/year. These values are below the world average values, except EDR and AEDR with mean values higher than the world standard. The comparison of radiation dose rates revealed that radionuclides contributed 6.7% to background radiation. The equivalent dose (EDorgans) for various organs of the body was calculated, and results showed that values do not pose any immediate health hazard. The excess lifetime cancer risk (ELCR) due to exposure to background radiation indicated that the dwellers and industrial workers in the study area may develop cancer over a lifetime due to accumulated dose.