Radiometric Mapping and Evaluation of Radiation Health Risk Parameters in Imo North Senatorial District, Nigeria

A Radiometric mapping and analysis of Radiation Health Risk Parameters of Imo North Senatorial District, Nigeria (situated between 7°4′48″ E and 7°25′48″ E, and 5°30′36″ N and 5°56′24″ N) was carried out through the use of two well Calibrated nuclear radiation meters, Radalert 100 and Digilert 200 and a GPS device, to measure the background Ionizing radiation exposure rate. Golden Software Surfer 20.1.195 and QGIS 3.16.8 were used for plotting radiation contour maps and radiometric map respectively. The average radiation exposure rates from thirty communities in the six local government areas of the district was 0.0128 ± 0.0006 mRh⁻¹. The average absorbed dose rate was 110.86 ± 4.77 nGyh⁻¹. The average annual effective dose equivalent (AEDE) result was 0.1136 ± 0.006 mSvy⁻¹. The excess life time cancer risk (ELCR) average values was (0.476 ± 0.02) × 10⁻³. The average radiation exposure rates was below the UNSCEAR 2008 world average of 0.013 mRh⁻¹ while the average of AEDE in this study are within the recommended safety values of 1.00 mSvy⁻¹ for the public as stipulated by the ICRP. The average absorbed dose and ELCR surpassed the world average of 84 nGyh⁻¹ and 0.29 × 10⁻³ respectively. The values recorded for absorbed dose rate and ELCR may not result in an acute health impact on residents of Imo North Senatorial District, but continuous exposure may likely result in stochastic radiation effects.