In vivogenotoxicity of high-intensity intermediate frequency magnetic fields in somatic cells and germ cells

Abstract

Intermediate frequency magnetic fields (IF-MFs) at ~85 kHz are one of the components of wireless power transfer (WPT) systems. However, the available data needed for the assessment of the safety of organisms from IF-MF exposure are scarce. Thus, there is an imminent need to accumulate evidence-based assessment data. In particular, if humans are exposed to IF-MF due to an accident or trouble, they are at increased risk of being exposed to high-intensity IF-MF within a short period. The already existing exposure system was improved to a system that could intermittently expose animals at 3 s intervals. This system allows the exposure of a mouse to high-intensity IF-MF (frequency: 82.3 kHz; induced electric field: 87 V/m, which was 3.8 times the basic restriction level for occupational exposure in the ICNIRP guideline), while regulating the heat generated by the coil. In vivo genotoxicity after IF-MF exposure was assessed using micronucleus (MN) test, Pig-a assay, and gpt assay. The results of MN test and Pig-a assay in hematopoietic cells revealed that neither the reticulocytes nor the mature erythrocytes exhibited significant increases in the IF-MF-exposed group compared with that in the sham-exposed group. In germ cells, MN test and gpt assay outcomes showed that IF-MF exposure did not cause any genetic or chromosomal abnormality. Based on these data, there was no genotoxic effect of our set IF-MF exposure on somatic and germ cells. These findings can contribute to the widespread use of WPT systems as effective data of IF-MF safety assessment.

Development of an <i>in vivo</i> pain assessment method for exposure to intermediate-frequency magnetic fields

“…Recently, Lee et al reported that most recent animal studies of IF-MFs have shown no effects on carcinogenesis, pregnancy, development, learning and memory behavior, or immunity (Lee et al, 2023). We have also assessed the various biological effects of IF-MF via genotoxicity in mice (Ohtani et al, 2023), immunotoxicity in developing rats (Ushiyama et al, 2014), and comprehensive gene expression using the cerebrum and liver of mice (Ohtani et al, 2019), as well as in studies using much higher levels of IF-MF, none of which showed any effects.…”