Assessment of background nuclear radiation and its health implications in selected cities of Ondo State, Nigeria

Abstract

This research explores the measurement of background nuclear radiation, rate of exposure and the radiological risk for the inhabitants of South-western Nigeria. The measurement was carried out using Rad*Scanner model 500VBR, which measures radiation dose in count per minute. The mean absorbed dose rate ranges between 147.26 ± 8.13 nGy h⁻¹ and 228.20 ± 20 nGy h⁻¹, the annual and collective annual outdoor effective dose equivalent, with collective health detriment were estimated using the obtained data. The mean annual outdoor effective dose equivalent was estimated at 268.37 ± 38.25 µSv y⁻¹. This value is below 1 mSv y⁻¹ limit recommended by ICRP but greater than 0.1 mSv y⁻¹ recommended by WHO. Using a population of 3,441,024, the mean collective effective dose equivalent was estimated at 923.46 ± 131.619 Man-Sv y^−1. The collective health detriment was estimated to be approximately 15 men which could vary depending on hours of exposure.

Keywords:

• Background nuclear radiation
• effective dose
• health detriment
• radiological risk