Performance of the Bismuth Germanate Total Body Chlorine Analyzer

The initial method for in-vivo determination of body chlorine (BC1) was total body neutron activation followed by whole body counting of activated chlorine1. Efforts to analyze total body chlorine (TBC1) using prompt-gamma/NaI system were successful, but the background in the chlorine region of interest 5 to 7 MeV was high and therefore the precision suffered2.