Assessment of chronic genotoxic effects in radiology technicians: A comparative study using the comet assay and γ-H2AX biomarker

Maged  Mostafa; Ebada  Abd AlRaouf; Mona  El Wassefy; Samir  Elmasry

Authors

Maged Mostafa Faculty of Medicine, Mansoura University, Egypt
Ebada Abd AlRaouf Faculty of Biotechnology, Sadat City University, Egypt
Mona El Wassefy Faculty of Biotechnology, Sadat City University, Egypt
Samir Elmasry Faculty of Medicine, Mansoura University, Egypt

Keywords:

Comet assay, DNA damage, ionizing radiation, occupational exposure, γ-H2AX

Abstract

Background: Healthcare workers, particularly radiology technicians, are chronically exposed to low-dose ionizing radiation (IR). While physical dosimetry monitors external exposure, biological monitoring of early genotoxic effects is crucial for risk assessment.

Objectives: To evaluate DNA damage in radiology technicians occupationally exposed to low-dose IR compared to nonexposed controls.

Methods: This case-control study included 50 radiology technicians and 50 matched controls. DNA damage in peripheral blood lymphocytes was assessed using the alkaline comet assay. A subset of participants (10 exposed and 10 controls) underwent γ-H2AX flow cytometric analysis for detection of DNA doublestrand breaks.

Results: The exposed group showed significant increases in DNA damage parameters, particularly tail intensity, tail moment and head intensity (P < 0.001). Receiver operating characteristic (ROC) analysis demonstrated excellent diagnostic performance for tail moment and head intensity (area under the curve (AUC) = 1.000). γ-H2AX analysis showed significantly higher mean fluorescence intensity and percentage of positive cells among exposed workers (P < 0.001). DNA damage correlated positively with occupational exposure duration.

Conclusion: Our findings suggest a link between long-term exposure to low-dose infrared radiation and DNA damage even when standard safety precautions are followed.

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