Reduction in radioactive internal contamination by 99m Tc among medical personnel in nuclear medicine facilities with the use of respiratory tract protection measures.

The main objective of the present publication was to assess the reduction of internal radioactive contamination with 99m Tc among medical personnel of nuclear medicine facilities using generally available respiratory tract protection systems. During the current research project, four respiratory tract protection systems were tested by estimation of 99m Tc activity levels in blood samples collected from medical personnel. Medical staff were equipped with a disposable surgical mask, a half mask with gas absorbers, a half mask with aerosol absorbers and a half mask with gas absorbers with added Petryanov filter. The presented results indicate that wearing only a disposable surgical mask may significantly reduce radioactive internal contamination among medical personnel and improve their safety in the workplace. The best results of reduced 99m Tc concentration in the blood were achieved by the use of a half mask with gas absorbers with added Pertryanov filters and a half mask with aerosol absorbers, where the reduction factors were estimated at 90% and 80%, respectively. Respiratory tract protection systems should become standard equipment for medical personnel performing ventilation-perfusion SPECT lung scans.