Measurement of Background Ionizing Radiation in Selected Buildings with Altitude within Delta State, Nigeria

Abstract

Anthropogenic activities play a crucial role in radiation exposure, resulting in a myriad of adverse health effects. Hence, the need to monitor and maintain exposure levels as low as reasonably achievable, particularly in residential areas. In the present study, the measurement of the background ionization radiation in selected buildings with Altitude within Delta State, Nigeria was carried out using a well calibrated radiation nuclear meter (Digilert 200). The study covers Warri and Asaba, which are the major cities in the state. The exposure rate varied from 0.007 to 0.020 mR/h with an overall mean value of 0.012 ± 0.030 to 0.016 ± 0.003 mR/h. The calculated absorbed doses rates ranged from 60.9 to 174.0 nGy/h with an overall mean of 107.3 ± 22.4 to 139.2 ± 27.51 nGy/h. The calculated annual effective doses equivalent ranged from 0.09 to 0.27 mSv/y with an overall mean of 0.16 ± 0.03 to 0.21 ± 0.04 mSv/y. The excess life cancer risk ranged from 0.32 to 0.93 with an overall mean annual effective dose equivalent was determined to be below the safe world recommended permissible limit of 1.00 mSv/y, while others slightly exceeded their respective global average safe thresholds. Therefore, there may not be any immediate radiological health effect on residents of the areas based on the data obtained.