Abstract

Monitoring of environmental radiation helps to ascertain healthy vicinity which is a catalyst to the economic development of the area. Activity concentration of naturally occurring radionuclides in three (3) dumpsites in Lagos State, Olusosun Landfill, Ojota, Ilupeju dumpsite and, Gbagada dumpsite Lagos state, Nigeria were investigated using gamma-ray spectroscopy to obtain the level of radioactive exposure hazards experienced by people living in these vicinities. A total of thirty soil samples were randomly collected into a polythene bag. They were oven-dried at 110°C, pulverized, and sieved. Quantities of the samples (400 g) were sealed in cylindrical sample holders and kept for about 28 days to attain secular equilibrium between 226Ra and its decay products before analysis using gamma-ray spectrometry. The mean activity concentration obtained for 40K, 238U, and 234Th at, Ilupeju, Gbagada, and Ojota were 339.23±33.66, 11.83±19.174, 11.95±22.752 Bq/kg, 337.56 ± 36.22, 11.49±22.14, 11.54 ± 19.33 Bq/kg and 334.87±32.44, 11.42±22.39, 11.56±18.52 Bq/kg respectively. The mean absorbed dose nGy/h, annual effective dose mSv/y were calculated and their results were found to be below the global values. The results indicate that the radiation level within the dumpsites poses no significant health risk to the people living close to the dumpsites.

Keywords: Activity Concentration, Radionuclide, Detector, and Hazard index