Objective Radiation doses to the general public and nuclear medicine technicians from patients undergoing ⁹⁹Tc^m-methylenediphosphonate(MDP) bone scintigraphy were estimated.

Methods A total of 64 patients (38 males and 26 females, aged 24–82 (55.1±12.8) years) undergoing bone scintigraphy with ⁹⁹Tc^m-MDP were retrospectively enrolled in this study. Approximately at 15 minutes after injection of ⁹⁹Tc^m-MDP, whole-body dose-equivalent rate (DR) was measured with a radiation-survey meter at 0.3 meter and 1.0 meter from the patients with nuclear radiation monitoring detector. On the basis of the human social contact model defined by the National Council on Radiation Protection and Measurements and human ⁹⁹Tc^m-MDP metabolic rate suggested by the International Commission of Radiological Protection, the radiation doses to the general public and the nuclear medicine technicians after exposure to patients undergoing ⁹⁹Tc^m-MDP bone scintigraphy were calculated.

Results The whole-body DR values of 64 patients at 15 minutes after injection of ⁹⁹Tc^m-MDP were 70.8–154.2 (105.5 ± 20.9) and 15.9–32.7 (22.6±3.6) μSv/h, respectively, at 0.3 meter and 1.0 meter. The following radiation doses were estimated: to a family member contacting with a patient at daytime 13.3–27.4 (18.9±3.0) μSv; to a family member sleeping with a patient at night 78.2–170.3 (116.5±23.4) μSv, to a colleague 17.6–36.2 (25.0±4.0) μSv and to a adjacent passenger 219.9–478.8 (327.5±65.7) μSv. The radiation dose to a technician per ⁹⁹Tc^m-MDP imaging patient was estimated to be 3.9–8.5 (5.8±1.2) μSv.

Conclusion The predicted radiation doses to the general public and technicians from exposure to patients undergoing ⁹⁹Tc^m-MDP bone scintigraphy are significantly lower than the regulatory dose limits.