99mTc internal contaminations measurements among nuclear medicine medical personnel during ventilation – perfusion SPECT lung scans

This paper presents results of measurements of 99m Tc activity concentration in air and nuclear medical personnel blood during ventilation–perfusion SPECT lung scans. 99m Tc activity measurements were conducted at the Nuclear Medicine Department, John Paul II Hospital, Krakow. Technicians and nurses who perform examinations were equipped with personal aspirators enabling air sampling to determine the radiation exposure at their workplaces. Measurements allowed to evaluate the concentration of 99m Tc in 14 air samples and it ranged from 7800 ± 600 to 10,000 ± 1000 Bq m −3 for air samples collected by technicians and from 390 ± 30 to 600 ± 40 Bq m −3 for air samples collected by nurses. In addition 99m Tc concentrations in blood of medical personnel were determined in 24 samples. For technicians the maximum 99m Tc blood concentration levels reached 920 ± 70 Bq L −1 and 1300 ± 100 Bq L −1 . In the case of nurses, the maximum estimated activity concentrations were about ten times lower, namely 71 ± 7 Bq L −1 and 39 ± 3 Bq L −1 . Although the intakes appear to be relatively high, the resulting annual effective doses are about 34 µSv for technicians and only 2 µSv for nurses.