2006 Volume 28 Issue 3 Pages 123-126
Epidemiological studies suggest that exposure to environmental and occupational electromagnetic fields (EMFs) contributes to the induction of brain tumors, leukemia, and other neoplasms. The aim of this study was to investigate the genotoxic effects of co-exposure to mitomycin C (MMC), a mutagen, and 50-Herz (Hz) EMFs, using an in vivo-ex vivo newborn rat astrocyte micronucleus assay. Three-day-old male Sprague-Dawley rats were co-exposed to 50-Hz EMFs and either 2.0 or 4.0 mg/kg of MMC. Brain cells were dissociated into single cells, cultured for 96 h, and stained with acridine orange and an antibody against glial fibrillary acidic protein. The frequency of micronucleated astrocytes was determined by fluorescence microscopy. The frequency of micronuclei was not increased in rat astrocytes exposed to EMFs alone. However, the frequencies of micronuclei significantly decreased in the rats exposed to 2.0 or 4.0 mg/kg MMC and a 7.5 or 10 mili Tesla (mT) EMF, in comparison to those in the rats exposed to 2.0 or 4.0 mg/kg MMC alone (sham-exposure, 0 mT EMF) for 72 h (p<0.01). Since we previously found that the same range of EMFs enhanced the genotoxicity of cisplatin in the same assay system as that used in the present study, it is suggestSed that effects of EMFs on the genotoxicities of chemicals co-exposed to rats are dependent on the chemicals.
