Jc. Toler et al., LONG-TERM, LOW-LEVEL EXPOSURE OF MICE PRONE TO MAMMARY-TUMORS TO 435-MHZ RADIOFREQUENCY RADIATION, Radiation research, 148(3), 1997, pp. 227-234
The purpose of this study was to determine if chronic, low-level expos
ure of mice prone to mammary tumors to 435 MHz radiofrequency (RF) rad
iation promotes an earlier onset, a faster growth rate or a greater to
tal incidence of mammary tumors than in sham-exposed controls. Two hun
dred female C3H/HeJ mice were exposed for 21 months (22 h/day, 7 days/
week) to a horizontally polarized 435 MHz pulse-wave (1.0 mu s pulse w
idth, 1.0 kHz pulse rate) RF radiation environment with an incident po
wer density of 1.0 mW/cm(2) (SAR = 0.32 W/kg). An additional 200 mice
were sham-exposed. Animals that died spontaneously, became moribund or
were euthanized after 21 months of exposure were completely necropsie
d; tissues were subjected to histopathological examinations. Concernin
g mammary carcinomas, there were no significant differences between th
e two groups with respect to latency to tumor onset, tumor growth rate
and overall tumor incidence. Histopathological examination revealed n
o significant differences in numbers of malignant, metastatic or benig
n neoplasms between groups. Survival probability was estimated by the
Kaplan-Meier method; no significant difference between groups was note
d (Cox's test). Under the conditions of this long-term study, low-leve
l exposure of mice prone to mammary tumors to 435 MHz RF radiation did
not affect the incidence of mammary tumors, tumor growth rate, latenc
y to tumor onset or animal longevity when compared to sham-exposed con
trols. (C) 1997 by Radiation Research Society.