238U, 235U, 137Cs and 133Xe in soils from two campuses in University of Douala-Cameroon

An evaluation of 238U, 235U, 137Cs and 133Xe in soils from two campuses in University of Douala-Cameroon using gamma spectroscopy based Broad Energy Germanium Detector (BEGe6530) has been performed. The mean activities in soils from Campuse 1 were 40.16±8.98 Bq/kg for 238U, 3.39±0.33 Bq/kg for 235U, 0.46±0.33 Bq/kg for 137Cs and 0.14±0.16 Bq/kg for 133Xe. In Campus 2, the mean activities in soils were 31.45±12.24 Bq/kg, 3.02±1.00 Bq/kg, 0.30±0.26 Bq/kg and 0.35±0.24 Bq/kg for 238U, 235U, 137Cs and 133Xe, respectively. Using the in situ survey meter, the mean values of the absorbed dose rate measured was 71.43 nGy/h for Campus 1 and 62.72 nGy/h for Campus 2. The evaluated average outdoor effective dose for Campus 1 and 2 were 87.60 µSv/yr and 76.93 µSv/yr, respectively. The overall results obtained in this work were generally low compared to that of UNSCEAR.