To investigate the carcinogenic activity of 2.45 GHz microwave radiation combined with benzpyrene or X-rays, using an in vitro assay for malignant transformation in C3H 10T1/2 mouse embryo fibroblasts.
Additional experiments were performed to assess the effect of a non-cytotoxic and non-transforming concentration of the tumor promotor TPA on transformation induction in cells treated with microwave radiation and X-rays.
|Pulse width||83 µs|
|Packets per second||1|
|Repetition frequency||120 Hz|
Microwave exposure reduced the plating efficiency of 50%, while TPA increased it by 40%. Microwave radiation had no effect on transformation induced by benzpyrene or X-rays in the absence of tumor promoter. TPA treatment of cells previously irradiated with microwaves and X-rays yielded a statistically significant increase (3.5- or 1.6-fold) in transformation when compared with the transformation frequency of cells previously irradiated with X-rays alone at 1.5 and 4.5 Gy, respectively. The results suggest that low-level 2.45 GHz microwave radiation can induce latent transformation damage which can then be revealed by the action of tumor promoters.