Lai H and Singh NP
In a series of experiments, rats were subjected to low-intensity pulsed an continuous-wave 2450 MHz microwaves for two hours, and their brain cells subsequently examined for evidence of breaks in DNA, which have been observed in aging, degenerative disease of the nervous system, and cancer.
In the first paper (1995), no significant effects were found immediately after the exposure. However, at 4 hours after exposure, the authors found a dose rate-dependent (0.6 and 1.2 W/kg whole body SAR) increase in DNA single-strand breaks. They also found increases in DNA single-strand breaks in rats exposed to continuous-wave 2450 MHz microwaves, both immediately and 4 hours after exposure (SAR 1.2 W/kg).
In the second paper (1996), single-strand and double-strand breaks were observed at 4 hours after exposure to either the pulsed or continuous-wave radiation.
In the third (1997), the authors found that melatonin and another substance, PBN (N-tert-butyl-alpha-phenylnitrone), blocked the effect of the microwave radiation. Since both melatonin and PBN are efficient free radical scavengers, the authors hypothesized that free radical scavengers are involved in the observed DNA damage to the rat brain cells.