Occupational radiation exposure among healthcare workers in fluoroscopy-guided interventional procedures: A multi-centre longitudinal study in Tanzania

Abstract

Fluoroscopy-guided interventional procedures (FGIPs) are increasingly used in modern medicine because they offer minimally invasive diagnostic and therapeutic options, but they also expose healthcare workers to ionizing radiation. In Tanzania, occupational dose data for staff involved in FGIPs remain limited. This study assessed occupational radiation exposure among workers involved in FGIPs in selected Tanzanian referral hospitals, with emphasis on differences across professional categories, hospitals, and monitoring periods. A hybrid retrospective-prospective longitudinal study was conducted among 37 occupationally exposed workers from four referral hospitals. Retrospective dose records were collected for two three-month quarters from May to October 2025, followed by prospective monitoring for two additional quarters from November 2025 to April 2026 using thermoluminescent dosimeters (LiF:Mg,Ti). The mean annual personal dose equivalent was 1.14 ± 0.20 mSv (range: 0.60–1.39 mSv). All values were below the ICRP-recommended occupational dose limit of 20 mSv year⁻¹. Mean annual personal dose equivalent differed significantly across professional categories (Welch ANOVA, p < 0.001; η² = 0.658), whereas differences between hospitals were not significant (ANOVA, p = 0.318; η² = 0.10). Linear mixed-effects modelling showed a modest but statistically significant variation in quarterly personal dose equivalent over time (p = 0.029). These findings support continued dose monitoring and targeted radiation protection for personnel with higher occupational exposure.