Unknown authors
Pregnant ICR mice were exposed to 2450 MHz continuous-wave radiation for 3 hours daily from gestational day 7 to 17 at an average power density of 10 mW/cm². Pups were tested from day 1 to day 21 postpartum using a battery of behavioral and neurological tests, all conducted blind. Exposed pups showed delayed initiation of several behavioral responses compared with sham-exposed pups. The delay affected the time needed for all exposed pups to achieve each response, but all exposed pups eventually reached the same developmental level as controls.
Unknown authors
The study used BALB/c mice and the chemical carcinogens 3,4-benzopyrene applied to skin and diethylnitrosamine injected intraperitoneally. Both carcinogens led to neoplasms with immunosuppression in the final stage of tumor growth. Exposure at 20 mW/cm2 caused earlier immunosuppression and earlier tumor appearance, while 5 mW/cm2 produced only slight insignificant differences.
Unknown authors
Researchers monitored colonic temperature and temperatures in the cerebral cortex, hypothalamus, cerebellum, and medulla of unanesthetized rats that were either sham-exposed or exposed to 2450 MHz CW microwaves at 65 mW/cm² for 30 or 90 minutes. Regional brain and colonic temperatures were significantly higher in exposed rats than in sham controls after both exposure durations. In sham rats the mean cortical temperature was 36.6°C. After 30 minutes of exposure cortical temperature rose to 40.0°C and after 90 minutes to 42.1°C. Cortical and cerebellar temperatures were slightly lower than colonic temperature, while hypothalamic and medullary temperatures were slightly higher in all groups.
Unknown authors
Researchers exposed 20 young male rats to pulsed microwaves at 24.4 mW/cm² for seven weeks, five days per week, four hours per day. A significant drop in absolute lymphocyte count occurred from the fifth week of irradiation and persisted until ten weeks after exposure ended. The percentage of large lymphocytes remained relatively higher in irradiated rats throughout most of the exposure period. No significant changes were found in nucleolar coefficient or nucleoli types except a transient drop in the nucleolar coefficient during the first week. In a second experiment, adult rats were exposed to 1 mW/cm² pulsed microwaves for 14 weeks and no significant changes were found in lymphocyte counts or nucleolar characteristics.
Unknown authors
Unknown authors
A. DEFICIS, J.C. DUMAS, S. LAURENS
Unknown authors
Researchers exposed mice to 2450 MHz microwaves at 0.6 watts forward power with an absorbed dose of 12 to 15 mW/g and measured CR+ spleen cells on days 3 and 6. A minimum 15-minute exposure induced a significant increase by day 3 that peaked at day 6, and a maximal increase occurred after 45 minutes. The increase did not require mature T cells and only occurred in mice older than 6 to 8 weeks, indicating a maturation prerequisite. The effect was not mediated by LPS, and susceptibility mapped to the H-2k haplotype.
Unknown authors
Researchers exposed 20 time-bred rats to 100-MHz RF at 500 W forward power (50 mW/cm²) starting on day 6 of pregnancy for 4 hours per day, 7 days per week. The mean specific absorption rate for rats was 2.8 mW/g. No differences were found in growth, neurological development, locomotor activity, hematology, immune function, or mutagenicity between exposed and sham-exposed rats. However, significant changes in regional brain acetylcholinesterase activities were observed in chronically exposed rats.
Unknown authors
Researchers measured whole-body specific absorption rates in single mice and rats exposed to 2450 MHz, 425 MHz, or 100 MHz radiation using twin-well calorimetry. Exposures were performed in three orientations relative to the fields and for three animal weight ranges per species. The 2450 MHz exposures were conducted in an anechoic chamber in the far field, while 425 MHz and 100 MHz exposures used TEM transmission lines (Crawford cells). Measured SAR values were in reasonable agreement with the Radiofrequency Radiation Dosimetry Handbook values but tended to be greater by a factor of 2 and as high as a factor of 4.
Unknown authors
Female BALB/c mice were exposed to continuous-wave or pulsed-wave 425-MHz radiation in a TEM transmission line for one hour per day over five consecutive days, with sham-exposed controls. Continuous-wave exposures used power densities of 39, 10, and 2.5 mW/cm², while pulsed-wave exposures used 9, 2.5, and 0.63 mW/cm² with a 1 msec pulse at 250 pulses per second. Mice exposed to pulsed-wave at 9.0 mW/cm² showed increased colonic temperature, but continuous-wave at 39 mW/cm² did not, and peripheral blood cell counts were unchanged. The primary immune response to sheep red blood cells, measured by plaque-forming cell and hemagglutination assays, did not differ between sham and exposed groups or between continuous-wave and pulsed-wave exposures.
Unknown authors
Researchers examined the acute effects of pulsed 2800 MHz microwave radiation on repeated acquisition learning in three rats. Rats were exposed for 30 minutes to five power densities (0.25, 0.5, 1.0, 5.0, and 10.0 mW/cm²) before test sessions.
Unknown authors
Forty dams were exposed to 2450 MHz microwaves at 31 mW/g or 17 mW/g for 20 minutes on gestational days 8, 10, 12, or 14, while eight received sham exposures and eight served as cage controls. In the 31 mW/g group, 30% of implantations were resorbed and 17% of fetuses had abnormalities, compared to lower rates in other groups. Fetal body mass decreased at 31 mW/g, and fetal brain mass was affected by treatment condition and gestational day.
Unknown authors
Handling alone lowered pregnancy rate from 86 percent to 72 percent during days 1-6, with further drops to 65 percent at 21 mW/cm2 and 50 percent at 30 mW/cm2, while heated controls showed no extra decrease. Congenital malformations increased significantly only at 30 mW/cm2 during days 6-15, rising from 1.7 percent to 3.1 percent, with two-thirds being cleft palate.
Unknown authors
Fifty-eight male Long-Evans rats were exposed to 2.45 GHz continuous-wave microwaves for four hours at power densities of 0, 0.1, 1, 10, 25, and 40 mW/cm². Rats exposed to 0.1 and 1 mW/cm² had significantly lower serum corticosterone than sham-exposed rats, while rats exposed to 40 mW/cm² had significantly higher levels, and no changes occurred at 10 and 25 mW/cm². Colonic temperature increased significantly at 10, 25, and 40 mW/cm² but not at lower intensities.
H. Lai, A. Horita, A.W. Guy
Researchers exposed rats to continuous-wave or pulsed 2450-MHz microwaves at 0.6 W/kg for 45 minutes in waveguides or anechoic chambers. Frontal cortical choline uptake decreased under all irradiation conditions. Hippocampal choline uptake decreased in animals exposed to pulsed microwaves. Striatal choline uptake decreased after exposure in the miniature anechoic chamber. Hypothalamic choline uptake was not significantly affected.
Phillips, Richard D., Hunt, Evans L., King, Nancy W.
Stern
During each session, alternating 15-minute control and exposure periods presented 2450 MHz continuous wave microwaves at power densities of 5, 10, and 20 mW/cm². The proportion of time the heat lamp stayed on decreased as microwave power density increased, and a linear regression showed an intercept of 0.324, slope of -0.0063 (p<0.001), with power density accounting for 61% of the variation. Randomization tests confirmed significant differences at all power densities versus zero exposure (p<0.003), except at 5 mW/cm² versus all zero exposures (p=0.023) and versus adjacent 10 mW/cm² (p=0.021).
L. MIRO, R. LOUBIERE, A. PFISTER
