Chromosomal aberrations in subjects exposed to ionizing radiation
Dubravka Jovicic1, Snezana Milacic, Natasa Milic
1Clinical Center of Serbia, Institute of Occupational Health and Radiological Protection, Belgrade, Serbia. jduca@yubc.net
Summary
Occupational radiation exposure can cause lasting DNA damage. Some workers showed persistent chromosomal aberrations (CA) even after 9 months away from radiation, indicating variable recovery and radiosensitivity.
Area of Science:
- Radiation Biology
- Occupational Health
- Genetics
Background:
- Chronic low-dose ionizing radiation exposure poses cumulative risks.
- Assessing biological responses to occupational radiation is crucial.
- DNA damage and repair mechanisms are key to understanding radiation effects.
Purpose of the Study:
- To investigate DNA damage recovery in radiation-exposed workers.
- To examine chromosomal aberrations (CA) at two time points.
- To identify interindividual differences in radiosensitivity and repair.
Main Methods:
- Cytogenetic analysis of chromosomal aberrations (CA).
- Comparison of exposed workers (n=30) and unexposed controls (n=64).
- Re-examination of exposed subjects after 9 months removal from radiation source.
Main Results:
- 16.67% of exposed workers had persistent unstable CA after 9 months.
- Exposed group showed a significant increase in unstable aberrations (p < 0.05).
- Significant decrease in dicentrics, acentric fragments, and rings post-exposure removal; slight, non-significant increase in chromatid/isochromatid breaks.
Conclusions:
- DNA damage recovery from occupational radiation is highly variable.
- Interindividual differences in radiosensitivity and cellular repair exist.
- Persistent CA suggest long-term biological effects of chronic low-dose radiation exposure.
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