Assessment of DNA damage in healthcare workers occupationally exposed to low doses of ionizing radiation in the comet assay: Meta-analysis

Exposing the human body to ionizing radiation may result in carcinogenesis. However, the effects of low doses of ionizing radiation are unclear and need to be further explored. Medical workers are considered the largest group of individuals who are exposed to low doses of ionizing radiation. In this paper, we conduct a meta-analysis to review the DNA damage induced by low doses of ionizing radiation in healthcare workers occupationally exposed to low doses of ionizing radiation by using the comet assay. We identified 9 publications that were suited for a formal meta-analysis based on the standardized mean difference (SMD) between the study groups. The effective dose of exposed workers for all 9 studies is (<20 mSv/year), not exceeding the occupational exposure dose limit. The evaluation of these 9 studies indicated higher levels of DNA damage in the exposed healthcare worker group than in the unexposed healthcare worker group [random effects model: SMD for tail length 11.35, 95% confidence interval (8.10, 14.59), SMD for tail moment 7.97, 95% confidence interval (4.39, 11.55), SMD for tail intensity 3.90, 95% confidence interval (1.68, 6.12)].