To evaluate whether the TDMA (Time Division Multiple Access) cellular phone met some of the defining criteria of known neurocarcinogenic agents (in this case ENU (ethylnitrosourea, a carcinogen)) in an animal model which include 1) a consistent capability to increase tumor incidence, 2) a reduction in latent period, 3) establishment of a direct dose-effect relationship, 4) a shift toward more anaplastic tumor types, and 5) an increased susceptibility of fetal tissues to neurocarcinogens compared with adult tissues.
Modulation type: pulsed
Exposure duration: continuous for about 25 days, see add. information
Modulation type: pulsed
Rats were assigned to four experimental groups: Sham/Sham, Sham/Field, ENU/Sham and ENU/Field. A single dose of ENU was applied on gestation day 18 via the tail vein. Buffer alone was applied to the sham-injected groups.
|Exposure room||Far field conditions were simulated with an approx. plane wave in a large tapered horn radiator of square aperture (2 x 2 m²) and 4.2 m length (about 12 wavelengths). Circular polarization was achieved using crossed dipole antennae placed in front of a ground plane at the apex of the horn and phase-shifted antenna feeds.|
|Setup||Rat cages were positioned (not randomized daily) in a vertically oriented 3 x 3 matrix at the aperture of the horn in a "target chamber" that was 2.5 m square and 1.5 m deep, and lined with RF-absorbing foam. Sham exposures were performed in a square chamber of identical dimensions and materials, but the tapered section was truncated to 58 cm.|
|Additional info||Far field exposure of rats in their home cages began on gestation day 19 and continued until the pups were aged 21 days (about 25 days in total).|
No parameters are specified for this exposure.
|Exposure room||Twelve carousel exposure platforms were used each with 10 rats confined in PVC tubular restraints of different sizes and oriented radially around a central antenna. The antennas of adjacent carousels were spaced 1.7 m apart. Sham exposure was performed in identical carousels located in a different room.|
|Setup||The distance to the antenna from the tip of the nose was 30 mm from weaning to 120 days, and 45 mm thereafter.|
|Additional info||Near field exposure began at age 33 days and was performed on 4 consecutive days weekly until termination of the experiment at 709-712 days of age (376 exposures in total).|
|power||2.5 W||-||-||-||± 0.1 W|
|SAR||1.4 W/kg||average over mass||calculated||brain||male 250 g at 30 cm|
|SAR||1.2 W/kg||average over mass||calculated||brain||male 450 g at 45 cm|
|SAR||1.1 W/kg||average over mass||calculated||brain||female 150 g at 30 cm|
|SAR||1 W/kg||average over mass||calculated||brain||female 250 g at 45 cm|
The study shows no increased tumorigenesis in the mammalian CNS from exposure to TDMA signals. Overall, the TDMA field-exposed animals exhibited trends toward a reduced incidence of spontaneous CNS tumors and ENU (ethylnitrosourea)-induced CNS tumors.