Biological effects of low-dose ionizing radiation exposure on interventional cardiologists

Abstract

Background: Interventional cardiologists (ICs) are likely to receive high radiation exposure as a result of procedures they undertake. Aims: To assess the effects of low-dose X-ray radiation exposure on chromosomal damage and on selected indices of cellular and humoral immunity in ICs. Methods: The study population consisted of 37 ICs and 37 clinical physicians as the control group with similar age, sex and duration of employment, without any work-related exposure to ionizing radiation. Cytogenetic studies were performed by chromosome aberration analysis and immunological studies by flow cytometry, enzyme-linked immunosorbent assay and immunodiffusion techniques. Results: The frequencies of aberrant cells, chromosome breaks and dicentrics plus centric rings were significantly higher in the exposed group compared to the control group (P < 0.05; P < 0.01; P < 0.001, respectively), without positive correlation between the frequency of dicentric and centric ring aberrations and the cumulative doses of the ICs (r = 0.24, not significant). A significant increase was observed in the expression of activation marker CD69 on TCD4+ stimulated cells in serum immunoglobulin G and interleukin (IL)-2 (P < 0.05) and a significant decrease in serum IL-10 (P < 0.05) in the ICs compared with that of the control group. There was no statistical difference between the two groups in terms of number of white blood cells and lymphocytes, CD3+, CD4+ and CD8+ T cells, CD19+ and CD16+ 56+ cells and concentrations of interferon (IFN)-γ, IL-4, IL-6 and IL-8 cytokines. Conclusions: While cytogenetic results show higher chromosomal damage, some immune responses are stimulated or modulated immunologically in ICs. © The Author 2010. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved.