Biological effects of ionizing radiation combined with extremely low frequency magnetic fields among occupationally exposed X-ray technicians

The human body is susceptible to ionizing radiation penetration resulting in cancer and other adverse health outcomes. One potent ionizing radiation source that has uses in medicine is X-rays. Globally, about 2.3 million and in Pakistan about 26,046 registered medical technicians are exposed to X-rays. Along with X-rays, these X-ray technicians are also potentially exposed to extremely low frequency magnetic field (ELF MF) from X-ray machines and other electrical devices. This study investigated the individual and combined effects of X-rays and ELF MF in the form of molecular mechanism including disruption of antioxidant enzyme activities, generation of reactive oxygen species, and the DNA damage. A total of 250 healthy workers were enrolled in this study; divided into ionizing radiation exposed and un-exposed groups. Along with exposure to ionizing radiation and ELF MF, information about exposure to potential confounding factors and effect modifiers was also collected. The results showed a statistically significant increased risk of DNA damage in the X-ray exposed group 20.3 ± 11.2 compared to un-exposed group 10.3 ± 5.85, p < 0.001. Also, antioxidant enzymes activities were statistically significantly higher in the exposed group Vs. un-exposed group for CAT: 12.1 ± 4.53 Vs. 9.67 ± 4.99; p < 0.001 and MDA: 9.36 ± 6.55 Vs. 5.92 ± 4.58; p < 0.001. However, the increase for SOD was not statistically significant (7.75 ± 5.58 Vs. 7.45 ± 4.83; p= 0.648). The combined exposure of ionizing radiation and ELF MF (≥0.4 μT) increased the impact for DNA damage only where changes in all the antioxidant enzymes were not meaningful. The age was statistically significantly associated with DNA damage and SOD activity. Also, the risk increased with dose-response (duration of employment) and highest DNA damage was observed in workers with work experience of ≥10 years. The study findings are useful in reporting the adverse health effects of exposure to occupational X-rays radiation and also in educating the laboratory technicians about the potentially harmful parts of their work.