Mouse embryonic stem (ES) cells were used as an experimental model to study the effects of
intermittent EMF exposures (5min on/30 minutes off). ELF-EMF exposure (2mT 50Hz with worst-case distortions for supply) to ES-derived neural cells significantly affected transcript levels of the apoptosis-related bcl-2, bax, and cell cycle regulatory "growth arrest DNA damage inducible" GADD45 genes, whereas mRNA levels of neural-specific genes were not affected. RF-EMF exposure (GSM-1800 simulated exposure at time-averaged SAR of 1.5 W/kg) of neural progenitor cells resulted in down-regulation of neural-specific Nurr1 and in up-regulation of bax and GADD45 mRNA levels. Short-term RF-EMF exposure for 6 h, but not for 48 h, resulted in a low and transient increase of DNA double-strand breaks.