Trends in External Radiation Exposure among the U.S Navy Medical Personnel Working in Nuclear Medicine Departments from 2003 to 2020

Abstract

Objectives: To assess trends in external occupational exposure of nuclear medicine (NM) workers from United States Navy (USN) medical centers from 2003 to 2020 and compare them with previously published data on NM workers from US civilian hospitals. Materials and methods: Analysis of the annual personal dose equivalents, deep dose equivalents Hp(10) (DDE) and shallow dose equivalents Hp(0.07) (skin dose) recorded using the DT-702/PD was conducted on 528 NM personnel working in USN medical centers. Also, analysis of 1,357 annual shallow dose equivalents Hp(0.07) (extremity dose) recorded using DXT-RAD was conducted on 285 NM workers. The data used in the study was provided by the United States Navy Dosimetry Center (NDC). Summary statistics of the distributions of annual and cumulative DDE, skin doses and extremity doses are provided in this study. Annual doses of nuclear medicine personnel working in Navy hospitals/clinics that perform PET imaging besides general nuclear medicine studies were identified using publicly available websites’ information, analyzed and compared with those who work in nuclear medicine facilities that perform only general NM studies. Doses from the two groups were compared using a two-sample t-test with 95% confidence interval. Results: Median annual doses of 0.38 mSv (IQR, 0.05-1.27 mSv; mean, 0.82 mSv), 0.37 mSv (IQR, 0.06 – 1.22 mSv; mean = 0.80 mSv), and 2.89 mSv (IQR = 0.76 – 7.86 mSv; mean = 6.65 mSv) for the DDE, skin dose and extremity dose, respectively, were observed in 2003–2020. Median cumulative DDE, skin dose and extremity dose over 2003–2020 were 0.39 mSv (IQR = 0.05 – 3.18 mSv; mean = 2.96 mSv) and 0.39 mSv (IQR = 0.05 – 3.08 mSv; mean = 2.90 mSv), and 13.0 mSv (IQR =2.89 – 38.5 mSv; mean = 31.6 mSv), respectively. Median annual DDE, skin and extremity doses to workers from identified PET facilities were 0.44 mSv (IQR= 0.06 – 1.60 mSv; mean = 0.99 mSv), 0.42 mSv (IQR = 0.06 – 1.58 mSv; mean = 0.97 mSv) and 3.16 mSv (IQR = 0.73 – 9.51 mSv; mean = 8.74 mSv), respectively, against 0.29 mSv (IQR = 0.06 – 0.95 mSv; mean = 0.65 mSv), 0.30 mSv (IQR =0.06 – 0.95 mSv; mean = 0.63 mSv) and 2.52 mSv (IQR = 0.76 – 6.19 mSv; mean = 4.72 mSv) to workers from non-PET facilities. The resultant p-value (p