Biological effects of low-dose ionizing radiation exposure on interventional cardiologists.
BACKGROUND
Interventional cardiologists (ICs) are likely to receive high radiation exposure as a result of procedures they undertake.


OBJECTIVE
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)-gamma, 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.
Zakeri
F
F
Agriculture, Medicine and Industry Research School-Nuclear Sciences and Technology Research Institute and Iranian Nuclear Regulatory Authority, PO Box 14155-4494, Tehran, Iran. fzakeri@aeoi.org.ir
Hirobe
T
T
Akbari Noghabi
K
K
D000328:Adult; D002309:Cardiology; D016022:Case-Control Studies; D002869:Chromosome Aberrations / Q000528:radiation effects / Q000706:statistics & numerical data*; D020732:Cytogenetic Analysis / Q000379:methods; D016207:Cytokines / Q000378:metabolism; D004307:Dose-Response Relationship, Radiation; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007111:Immunity, Cellular / Q000528:radiation effects*; D056724:Immunity, Humoral / Q000528:radiation effects*; D005779:Immunodiffusion; D007136:Immunoglobulins / Q000097:blood; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000453:epidemiology* / Q000276:immunology; D016273:Occupational Exposure / Q000009:adverse effects*; D011839:Radiation, Ionizing; D015642:Radiology, Interventional
D016207:Cytokines; D007136:Immunoglobulins