Detection of the chemical changes in blood, liver, and brain caused by electromagnetic field exposure using Raman spectroscopy, biochemical assays combined with multivariate analyses

Photodiagnosis Photodyn Ther. 2022 Jun;38:102779. doi: 10.1016/j.pdpdt.2022.102779. Epub 2022 Feb 18.


The effects of the electromagnetic field on living organisms have been studied for several years. In this article, we showed what kind of cold change an extremely low-frequency electromagnetic field (ELF-MF) exposure 500 μT 50 Hz by using a Meritt Coil System causes in the samples of the brain and liver samples. To measure oxidative load, we measured malondialdehyde (MDA) and glutathione (GSH) levels. To identify the chemical changes, we collected Raman spectra of cerebellum, left brain, right brain and liver tissue from the control group of animals and from the animal, which were exposed to an electromagnetic field (ELF-MF group). Obtained results showed, that lipid peroxidation was increased and the antioxidant response was decreased. In the brain samples the shift of peaks corresponding to the amide III vibrations existed after ELF-MF exposure. Structural changes were detected in CH2 vibrations originating from lipids in both hemispheres. Additionally, the number of amide III bonds was increased with ELF-MF exposure in the cerebellum and left-brain tissue. In liver tissue higher Raman intensities were visible in the tissues from the ELF-MF group. In this group electromagnetic field also caused structural changes in lipids. Principal component analysis (PCA) showed, that it is possible to distinguish ELF-MF and control groups. Consequently, hierarchical component analysis (HCA) showed that tissues from ELF-MF and control groups separately created similarity with the groups. Obtained results suggest that the electromagnetic field caused structural and quantitative chemical changes in brain and liver tissue. Additionally, present data suggest that ELF-MF plays an important role in the regulation of enzyme activity and has effects on biochemical processes, possibly improved by production of ROS.

Keywords: Hierarchical component analysis; Low-frequency electromagnetic fields; Oxidative load; Principal component analysis; Raman spectroscopy.

MeSH terms

  • Amides
  • Animals
  • Brain
  • Electromagnetic Fields*
  • Lipids
  • Liver
  • Multivariate Analysis
  • Photochemotherapy* / methods
  • Spectrum Analysis, Raman


  • Amides
  • Lipids