Estimation of the total body burden for some individuals using whole body counter

Abstract

The current research study aims to estimate the total body burden and internal contamination for some public and occupational workers at Nuclear Research Center, NRC, and Egypt using Accuscan II whole body counter. Material and Method WBC consist of three parts; 25% coaxial germanium detector connected with electronic circuits, Shadow shield and transfer phantom. The WBC was used to monitor the workers and public for the 99mTc, 131I and 40K in the total body geometry for acquisition time of 300 sec. The efficiency calibration was carried out for wide energy range from 59 keV to 1836.2 keV using a standard mixed source. A liquid vial mixed gamma source inserted in thyroid and total body geometry positions of transfer phantom. In addition, KCl salt is inserted in total body geometry position of transfer phantom in real geometry to confirm the calibration of 40K in the energy of 1460 keV. Results The minimum detectable amount for 99mTc, 131I and 40K was 178, 172 and 204 Bq respectively. 40K body content activity for males ranged from 3497 to 5594 Bq and specific activity of 40K was ranged from 43.7 to 75.3 Bq/Kg and for females ranged from 2797 to 4544 Bq and 40K specific activity ranged from 31.1 to 64 Bq/Kg. The annual internal effective dose from 40K for males ranged from 122 to 210 μSv with an average dose of 165 μSv and for females ranged from 86 to 163 μSv with an average dose of 135 μSv. Internal dose for individuals exposed to I131 ranged from 0.45 μSv to 168.5 μSv and for individuals exposed to 99mTc ranged from 1.78 μSv to 3.25 μSv. The estimated annual effective dose for 40K, 131I and 99mTc was within the ICRP recommendations.