Chronic low dose exposure of hospital workers to ionizing radiation leads to increased micronuclei frequency and reduced antioxidants in their peripheral blood lymphocytes

Abstract

Purpose: The regular low dose occupational exposure to ionizing radiation may induce deleterious health effects, which may be of particular interest to medical radiation workers who daily handle X-ray machines. Human peripheral blood lymphocytes are able to retain the signature of radiation-induced DNA damage, therefore, the present study was undertaken to investigate the DNA damage and antioxidants status in hospital workers occupationally exposed to low doses of X-rays.

Materials and methods: The peripheral blood lymphocytes of the occupationally exposed and control groups matched for age, gender, tobacco usage, and alcohol consumption were cultured and micronuclei frequency was determined. Activities of antioxidant enzymes and lipid peroxidation were also estimated in their plasma.

Results: The micronuclei frequency in the occupationally exposed group (n = 33), increased significantly (p < .0001) followed by reduced glutathione-s-transferase (p < .01) and catalase (p < .001) activities, and increased lipid peroxidation (p < .05) when compared to the control group (n = 33). Occupational exposure resulted in an effective dose ranging between 3.14 to 144.5 mSv (40.88 ± 39.86mSv) depending on the employment duration of 3–29 years (10.33 ± 7.05 years). A correlation between the micronuclei frequency (p < .05) and catalase activity (p < .05) existed in the occupationally exposed individuals depending on the smoking habit, age, duration of employment, cumulative exposure dose and number of patients handled per day.

Conclusions: We have observed that protracted low dose exposure to ionizing radiation is an inevitable occupational hazard leading to persistence of oxidative stress and increased genomic instability in the radiological technicians depending on the time spent with X-rays, cumulative dose received and the number of patients handled daily raising the risk of cancer development.

Keywords:

• Human
• lymphocytes
• ionizing radiation
• micronucleus
• antioxidants
• lipid peroxidation

Acknowledgments

The authors would like to acknowledge the cooperation extended by the participants without which the study would have not been possible. We thank Dr. Priyanka Badara, Oceanic Radiofrequency Scientific Advisory Association, Brisbane, Australia for her help in reading the manuscript and providing useful inputs.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the University Grants Commission, Government of India, New Delhi [Grant number F. 4-10/2010 (BSR)] to GCJ.

Notes on contributors

Zothan Siama

Dr. Zothan Siama is working as Assistant Professor at the Department of Zoology.

Mary Zosang-zuali

Mary Zosangzuali is graduate students who are pursuing their Ph.D. at the Department of Zoology, Mizoram University, Aizawl, India.

Annie Vanlalruati

Annie Vanlalruati is graduate students who are pursuing their Ph.D. at the Department of Zoology, Mizoram University, Aizawl, India.

Ganesh Chandra Jagetia

Professor Ganesh Chandra Jagetia is a well-known radiobiologist who worked at Kasturba Medical College Manipal from 1982 to 2007 in various capacities and thereafter at Mizoram University (2007–2017) as Dean of School of Life Sciences and Head of the Department of Zoology and has published more than 250 research publications to his credit.

Kham Suan Pau

Dr. Kham Suan Pau is a Medical Physicist and works at the Radiation Safety Agency, Directorate of Hospital and Medical Education, Aizawl, India.

Nachimuthu Senthil Kumar

Dr. Prof. N. Senthil Kumar is Head of the Department of Biotechnology, Mizoram University, Aizawl, India.