Dispersion of lodine (¹²⁵I) and Trapping of Dispersed ¹²⁵I by Charcoal Cartridges

Abstract

The dispersal rates of ¹²⁵I defined here as a dispersed activity in Bq per hour divided by the total activity contained in a solution, and the collection efficiency of dispersed ¹²⁵I by charcoal cartridges were measured under the various pH conditions in the solution.
The values of dispersal rate observed under working conditions in common biochemical procedures were (3.74±1.19) ×10^-4 (h^-1), (4.27±1.90) ×10^-4 (h^-1) and (6.31±2.05) ×10^-4 (h^-1) for alkaline, neutral and acidic conditions of the solution, respectively. And those values obtained by the evaporation of solution to dryness were elevated more than 100 to 1000 times independent of pH of the solution. Under the case of common biochemical procedures, nearly 90% of the dispersed ¹²⁵I was trapped on the 1st charcoal cartridge which was inserted between dispersal part and exhaust part. No ¹²⁵I was detected in the following 2nd and 3rd charcoal cartridges.