8,700 Studies Reviewed. 87.0% Found Biological Effects. The Evidence is Clear.
Shield Your Body
Whole Body / General

Microwave and Infra-red Effects on Heart Rate, Respiration Rate and Subcutaneous Temperature of The Rabbit

Bioeffects Seen

L. Birenbaum, I. T. Kaplan, W. Metlay, S. W. Rosenthal, M. M. Zaret · 1975

Share:

2.4 GHz microwave radiation caused immediate increases in heart rate, breathing, and body temperature in rabbits, with respiratory effects 20 times stronger than cardiac changes.

Plain English Summary

Summary written for general audiences

Researchers exposed unanesthetized rabbits to 2.4 GHz microwave radiation at various power levels up to 80 mW/cm², measuring heart rate, breathing, and body temperature. All three biological responses increased with higher microwave power levels, with breathing rate showing the most dramatic changes - increasing 20 times more than heart rate. The study demonstrates that microwave exposure at frequencies similar to modern wireless devices can trigger measurable physiological stress responses in living mammals.

Why This Matters

This 1975 study provides early evidence that microwave radiation at 2.4 GHz - the same frequency used by WiFi routers, Bluetooth devices, and microwave ovens today - can trigger immediate physiological stress responses in mammals. The fact that breathing rate increased 20 times more than heart rate suggests the respiratory system may be particularly sensitive to microwave exposure. What makes this research especially relevant is that the power levels tested (up to 80 mW/cm²) are within range of what you might encounter from high-powered wireless devices or standing very close to a microwave oven. The researchers found no difference between continuous and pulsed microwave exposure, indicating that the biological effect depends primarily on average power density rather than modulation pattern. This challenges industry claims that pulsed signals are inherently safer than continuous wave radiation.

Exposure Information

Specific exposure levels were not quantified in this study.

Cite This Study
L. Birenbaum, I. T. Kaplan, W. Metlay, S. W. Rosenthal, M. M. Zaret (1975). Microwave and Infra-red Effects on Heart Rate, Respiration Rate and Subcutaneous Temperature of The Rabbit.
Show BibTeX
@article{microwave_and_infra_red_effects_on_heart_rate_respiration_rate_and_subcutaneous__g5812,
  author = {L. Birenbaum and I. T. Kaplan and W. Metlay and S. W. Rosenthal and M. M. Zaret},
  title = {Microwave and Infra-red Effects on Heart Rate, Respiration Rate and Subcutaneous Temperature of The Rabbit},
  year = {1975},
  
  
}

Quick Questions About This Study

Yes, 2.4 GHz microwave exposure caused significant increases in rabbit breathing rates, with respiratory changes being 20 times greater than heart rate changes at the same power levels up to 80 mW/cm².
Microwave radiation at 2.4 GHz caused measurable increases in heart rate, breathing, and body temperature at power levels ranging from low levels up to 80 mW/cm², with greater effects at higher power densities.
No significant difference was found between pulsed and continuous wave 2.8 GHz microwave exposure at 20 mW/cm² average power. Both caused similar increases in heart rate, breathing, and temperature in rabbits.
While heart rate and breathing changes were similar between 2.4 GHz microwave and infrared exposure, infrared radiation caused faster and higher increases in subcutaneous temperature at the same power levels.
The respiratory system showed the strongest response to 2.4 GHz microwave exposure in rabbits, with breathing rate increases being 20 times greater than heart rate changes at equivalent power levels.