Radiochemical analysis of a wide range of I-131 activities in water and milk using well-type germanium detector

摘要

We report a study of a fast radiochemical method to determine the activity of I-131 via the radiochemical recovery obtained with a I-129 tracer. Previous methods were valid for low levels of I-131 activities. In the new method, we developed a correction using the 29.7-keV X-ray peak from Xe, taking into consideration that this peak originates from both and I-131 decay. This enables quantitation of high levels of I-131 activity. Furthermore, for a very high I-131 activity, one can use the 39.6-keV gamma peak which is unique to I-129. Combining both approaches enables quantitation of I-131 activities up to 200 times that of the I-129 recovery tracer.