An assessment of finger doses received by staff while preparing and injecting radiopharmaceuticals.

Good working practice and legal obligation impose a duty on nuclear medicine departments to check syringe activities before administration to a patient. If syringe guards are used to reduce staff exposure while drawing up injections, the guard has to be removed to measure the activity in a conventional reentrant ionization chamber type calibrator. Alternatively, the activity may be checked in a purpose-built syringe calibrator which allows the assay of the activity in the syringe without the need to remove the syringe guard. Finger doses received during the dose preparation and injection are a cause for concern. This study investigated the finger and whole-body doses received when using each of these calibrators, and compared the results with those obtained by an operator who did not measure the dose at all. The results demonstrated that although the finger doses are small, measurement of the syringe activities in a conventional ionization chamber increases the dose by a factor of 2 above that which would occur if no activity measurements were made, whereas the use of the specialized syringe calibrator gave finger doses only marginally above those obtained with no activity measurement.