114Insup(m) in 111In-radiopharmaceuticals and its contribution to the absorbed dose in the patient at investigations with 111In-labelled blood cells

Investigations with 111In labeled blood cells give a comparatively high effective dose equivalent in the patients in comparison to other modern nuclear medicine investigations. The presence of the long-lived radionuclide impurity 114Insup(m) may further increase the effective dose equivalent by up to 35%. If it, in contrary to the recommendations from the manufacturers, is used later than one weak after reference time the increase will still be higher