Study type: Medical/biological study (experimental study)

Effects of microwave exposure and temperature on survival of mice infected with Streptococcus pneumoniae med./bio.

By: Liddle CG, Putnam JP, Lewter OH
Published in: Bioelectromagnetics 1987; 8 (3): 295-302
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Aim of study (acc. to author)

To analyze the effects of exposure to microwave irradiation at various ambient temperatures (19, 22, 25, 28, 31, 34, 37, and 40°C) of the survival of a group of clinically ill animals.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 2.45 GHz
Modulation type: CW
Exposure duration: 4 h/d for 5 days

General information

for further information see also: Ali JS., Weil C., 1983, "Radiofrequency radiation exposure facilities for bio-effects research." EPA-600/2-83-018, March (NTIS PB83-229591), 54 pp all experiments were conducted at 19°C, 22°C, 25°C, 28°C, 31°C, 34°C, 37°C and 40°C

Exposure 1

Main characteristics
Frequency 2.45 GHz
Type
Exposure duration 4 h/d for 5 days
Modulation
Modulation type CW
Exposure setup
Exposure source
Setup mice in individual plastic containers (6 cm x 6 cm x 7 cm) placed in foamed polystyrene frames in a 5 x 5 array which was placed in the chamber; sides of anechoic chamber lined with high-power absorbing material, floor had pyramidal absorbers
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
power density 10 mW/cm² - - - -
SAR 6.8 W/kg - calculated - -

Reference articles

  • Guy AW (1979): Miniature anechoic chamber for chronic exposure of small animals to plane-wave microwave fields
  • Berman E et al. (1978): Observations of mouse fetuses after irradiation with 2.45 GHz microwaves

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • during exposure
  • after exposure

Main outcome of study (acc. to author)

Survival of the sham-exposed mice increased as ambient temperature increased from 19°C to 34°C. At ambient temperatures at or above 37°C the heat induced in the body exceeded the thermoregulatory capacity of the mice and deaths from hyperthermia occurred.
Survival of the microwave-exposed mice was significantly greater than survival of the sham-exposed mice (approximately 20%) at each ambient temperature below 34°C.
Based on an analysis of the data it appears that the hyperthermia induced by microwave exposure may be more effective in increasing survival in infected mice than hyperthermia produced by conventional methods. Microwave irradiation may be beneficial to infected mice at low and moderate ambient temperatures, but it is detrimental when combined with high ambient temperatures.

Study character:

Study funded by

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