Effects of 2.45-GHz electromagnetic fields with a wide range of SARs on micronucleus formation in CHO-K1 cells.

Koyama S, Isozumi Y, Suzuki Y, Taki M, Miyakoshi J.

ScientificWorldJournal 4 Suppl 2:29-40, 2004

There has been considerable discussion about the influence of high-frequency electromagnetic fields (HF EMF) on the human body. In particular, HF EMF used for mobile phones may be of great concern for human health.

In order to investigate the properties of HF EMF, we have examined the effects of 2.45-GHz EMF on micronucleus (MN) formation in Chinese hamster ovary (CHO)-K1 cells. MN formation is induced by chromosomal breakage or inhibition of spindles during cell division and leads to cell damage. We also examined the influence of heat on MN formation, since HFEMF exposure causes a rise in temperature. CHO-K1 cells were exposed to HF EMF for 2 h at average specific absorption rates (SARs) of 5, 10, 20, 50, 100, and 200 W/kg, and the effects on these cells were compared with those in sham-exposed control cells.

The cells were also treated with bleomycin alone as a positive control or with combined treatment of HF EMF exposure and bleomycin. Heat treatment was performed at temperatures of 37, 38, 39, 40, 41, and 42 degrees C.

The MN frequency in cells exposed to HF EMF at a SAR of lower than 50 W/kg did not differ from the sham-exposed controls, while those at SARs of 100 and 200 W/kg were significantly higher when compared with the sham-exposed controls. There was no apparent combined effect of HF EMF exposure and bleomycin treatment. On heat treatment at temperatures from 38-42 degrees C, the MN frequency increased in a temperature-dependent manner.

We also showed that an increase in SAR causes a rise in temperature and this may be connected to the increase in MN formation generated by exposure to HF EMF.