Main results of the Monte Carlo studies carried out for nuclear medicine practices within the ORAMED project

Need for harmonisation of extremity dose monitoring in nuclear medicine: results of a survey amongst national dose registries in Europe

Staff handling radiopharmaceuticals in nuclear medicine (NM) may receive significant extremity doses. Over the last decade in particular there has been an increase in NM procedures and new radiopharmaceuticals have been introduced. However, literature provides limited recent data on the exposure of the extremities. In addition, proper assessment of the equivalent dose to the skin can be difficult when applied to the fingertips. In order to gain insight in the actual exposure and to find out how European countries are dealing with monitoring of the extremities, a survey was performed amongst European regulatory authorities. The questions covered general aspects of the national dose registries (NDRs), the measured extremity doses and the practice of the monitoring of workers. The survey shows that extremity dosimetry is performed for about 25%-50% of the monitored workers in NM. Also, the recorded extremity doses in the NDRs are low (mean values 5-29 mSv yr^-1) compared to the dose limit. Despite the recommendations that have been published in the last 10 years, few countries provide guidance on the wearing position of extremity dosemeters and the correction factor to estimate the maximum equivalent skin dose from the measured dose. This may lead to an underestimation of the maximum skin dose. Thermoluminescence ring dosemeters are widely used, but wrist dosemeters are also very common, even though the correlation of the measurement with the maximum skin dose is worse than for ring dosemeters. Furthermore, not all countries had a central registration of the extremity dose at the time the survey was performed.

ASSESSMENT OF THE LOCAL EXPOSURE OF SKIN ON HANDS OF NUCLEAR MEDICINE WORKERS HANDLING 18F-LABELLED RADIOPHARMACEUTICALS: PRELIMINARY CZECH STUDY

The article summarises some preliminary results of the assessment of the exposure of hands of workers manipulating ¹⁸F-labelled radiopharmaceuticals based on personal monitoring at two nuclear medicine clinics in the Czech Republic. The measurements were carried out using special thermoluminescence dosemeters the readings of which could be interpreted in terms of the personal dose equivalent H_p(0.07) approximating the equivalent dose to the skin at various locations on the surface of both hands. The results have shown that out of 21 workers monitored, ∼43 % (preparation and applications of radiopharmaceuticals) may reach an exposure equal to three-tenth of the annual dose limit to the skin. At the same time, it can also be concluded that in ∼10 % cases of workers, the relevant dose limit may be exceeded.