Abstract
The gamma camera method described for assessing the degree of contamination of 99Tcm by 99Mo and other radionuclides emitting high energy photons is more reliable and sensitive than the standard ionisation chamber procedure, requires no additional equipment and is easy to apply. If an abnormal impurity level is detected in the eluate, a multichannel pulse height analyser may be used with the camera to identify and quantify the contamination.