To determine if prenatal radiofrequency exposure leads to impaired memory or behavior after birth, the authors performed behavioral and electrophysiological studies in mice exposed in utero to 800-1900 MHz radiofrequency irradiation from cellular phones.
39 pregnant mice were exposed for 9 or 15 h/day (n=6) or for 24 h/day (n=33) during their gestational days 1-17. 42 mice were sham exposed. The memory test was performed with 161 pups (82 exposed and 79 control mice). The light-dark box test (anxiety/hyperactivity) was performed on 141 pups (71 exposed and 70 control mice) and the step-down test (fearful behavior) on 98 mice (47 exposed and 51 control mice).
Electrophysiological measurements were performed with coronal cortical slices prepared from the prefrontal area of the brain and the ventral medial hypothalamus of 3-4 week old mice (n=9-14).
|Distance between exposed object and exposure source||4.5 cm|
|Chamber||13 experimental cages and 14 control cages, each holding 3 female mice and 1 male mouse|
|Setup||phones positioned above each cage over feeding bottle area at a distance of 4.5-22.3 cm from each mouse (depending on location of animals within cage); phones in muted, uninterrupted active call mode for the whole duration of the experiment|
|Sham exposure||A sham exposure was conducted.|
The different tests revealed that mice exposed in utero were hyperactive, had an impaired memory and decreased anxiety. Miniature excitatory postsynaptic potentials (EPSP) recording revealed that these behavioral changes were due to altered neuronal programming. Exposed mice exhibited exposure duration-dependent impaired glutamatergic synaptic transmission onto layer V pyramidal cells of the prefrontal cortex (i.e. synaptic efficacy of glutamatergic transmission decreased) and the effects were not limited to the cortex (effect also found in ventral medial hypothalamus).
The corticosterone level in the exposed dams was not significantly different from that in the control females, eliminating stress of dams as a source of the observed behavioral and electrophysiologic differences in the pups.
The data demonstrate that fetal exposure to 800-1900 MHz from cellular phones leads to behavioral and neurophysiological alterations that persist into adulthood. Further experiments are needed to determine the risk of exposure during pregnancy.