8,700 Studies Reviewed. 87.0% Found Biological Effects. The Evidence is Clear.

Rate Effects in Isolated Hearts Induced by Microwave Radiation

Bioeffects Seen

J. L. Lords, C. H. Durney, A. M. Borg, C. E. Tinney · 1974

Share:

960 MHz microwaves slowed heart rate in isolated hearts at just 3 milliwatts, suggesting direct nerve stimulation beyond heating effects.

Plain English Summary

Summary written for general audiences

Researchers exposed isolated frog hearts to 960 MHz microwave radiation and found it caused bradycardia (slowed heart rate) at very specific power levels around 3 milliwatts. This contradicted expectations since general heating typically speeds up heart rate, suggesting the microwaves directly stimulated remaining nerve tissue in the hearts.

Why This Matters

This 1974 study reveals something striking about microwave radiation's biological effects. The science demonstrates that 960 MHz microwaves can directly affect heart rhythm through nerve stimulation, not just heating. What makes this particularly relevant is that modern WiFi operates at 2.4 GHz and 5 GHz, while cell phones use frequencies between 700 MHz and 2.1 GHz - all in the same general microwave spectrum. The researchers found effects at just 3 milliwatts of absorbed power, which is remarkably low. For comparison, cell phones can emit up to 2 watts of power, though the amount your body actually absorbs varies by distance and usage patterns. The reality is that this early research suggested microwave radiation could trigger biological responses through non-thermal mechanisms - a finding that challenges the industry's long-held position that only heating effects matter.

Exposure Information

Specific exposure levels were not quantified in this study.

Cite This Study
J. L. Lords, C. H. Durney, A. M. Borg, C. E. Tinney (1974). Rate Effects in Isolated Hearts Induced by Microwave Radiation.
Show BibTeX
@article{rate_effects_in_isolated_hearts_induced_by_microwave_radiation_g4485,
  author = {J. L. Lords and C. H. Durney and A. M. Borg and C. E. Tinney},
  title = {Rate Effects in Isolated Hearts Induced by Microwave Radiation},
  year = {1974},
  
  
}

Quick Questions About This Study

Yes, this study found that 960 MHz microwave radiation caused bradycardia (slowed heart rate) in isolated hearts. The effect occurred at very specific power levels around 3 milliwatts of absorbed energy, contradicting typical heating responses.
The heart rate effects occurred at approximately 3 milliwatts of absorbed microwave power. This is a remarkably low power level, demonstrating that biological effects can occur at energy levels well below what causes significant tissue heating.
Researchers hypothesized the microwaves directly stimulated nerve remnants in the isolated hearts. This nerve stimulation caused bradycardia, which contrasts with tachycardia (faster heart rate) typically seen from generalized heating effects in living organisms.
The researchers used isolated poikilothermic hearts (cold-blooded animals like frogs) suspended in Ringer's solution. These isolated hearts allowed scientists to study direct microwave effects without interference from the animal's intact nervous system.
While 960 MHz isn't used by current consumer devices, it's in the same microwave spectrum as cell phones (700 MHz-2.1 GHz) and WiFi (2.4-5 GHz). This suggests similar biological mechanisms could occur with modern wireless technologies.