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Cardiovascular

Character of the effect of microwave on conduction velocity of frog ventricular muscle.

No Effects Found

Yee KC, Chou CK, Guy AW · 1994

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Microwave radiation at cell phone frequencies showed no effect on heart electrical conduction, even at exposure levels far above normal human limits.

Plain English Summary

Summary written for general audiences

Researchers exposed isolated frog hearts to 2.45 GHz microwave radiation (the same frequency used in microwave ovens and WiFi) for 2 hours at various power levels to see if it affected how electrical signals travel through heart muscle. They found no changes in the speed of electrical conduction through the heart tissue at any exposure level tested, including levels much higher than typical human exposure from wireless devices.

Why This Matters

This study provides reassuring evidence that microwave radiation at 2.45 GHz doesn't disrupt the heart's electrical conduction system, even at high exposure levels. The researchers tested SAR levels ranging from 0.003 W/kg (similar to what you might experience from a cell phone) up to 6 W/kg (well above typical human exposure limits). What makes this particularly relevant is that heart rhythm disturbances are among the most commonly reported symptoms by people who believe they're sensitive to EMF. While this was an animal study using isolated heart tissue, the results suggest that direct electromagnetic interference with cardiac conduction isn't likely the mechanism behind such reports. The reality is that this study adds to a body of research suggesting that EMF effects on heart function, if they exist, are likely more complex than simple electrical interference.

Exposure Details

SAR
0.003, 2, and 6 W/kg
Source/Device
2,450 MHz
Exposure Duration
2 hours

Where This Falls on the Concern Scale

Study Exposure Level in ContextStudy Exposure Level in ContextThis study: 0.003, 2, and 6 W/kgExtreme Concern - 0.1 W/kgFCC Limit - 1.6 W/kgEffects observed in the Slight Concern range (Building Biology)FCC limit is 533 times higher than this level
A logarithmic frequency spectrum from 10 Hz to 100 GHz showing where this study's 2.45 GHz exposure sits relative to common EMF sources.Where This Frequency Sits on the EMF SpectrumELFVLFLF / MFHF / VHFUHFSHFmm10 Hz100 GHzThis study: 2.45 GHzPower lines50/60 Hz5G mm28 GHzLogarithmic scale

Study Details

The aim of this study is to investigate Character of the effect of microwave on conduction velocity of frog ventricular muscle.

Thirty-two frog hearts were divided into four groups and placed individually in temperature-controll...

No significant difference in conduction velocity was found between the control and the exposed group...

Cite This Study
Yee KC, Chou CK, Guy AW (1994). Character of the effect of microwave on conduction velocity of frog ventricular muscle. Bioelectromagnetics 15(6):555-561, 1994.
Show BibTeX
@article{kc_1994_character_of_the_effect_3495,
  author = {Yee KC and Chou CK and Guy AW},
  title = {Character of the effect of microwave on conduction velocity of frog ventricular muscle.},
  year = {1994},
  
  url = {https://pubmed.ncbi.nlm.nih.gov/7880169/},
}
PubMed: 7880169

Cited By (5 papers)

Quick Questions About This Study

A 1994 study found no effects on electrical conduction in frog hearts exposed to 2.45 GHz microwave radiation for 2 hours. Researchers tested various power levels, including those much higher than typical human wireless device exposure, with no changes detected.
Research using the same 2.45 GHz frequency found in microwave ovens showed no impact on heart muscle electrical signal transmission. The study exposed isolated frog heart tissue for 2 hours at multiple power levels without detecting any conduction velocity changes.
A controlled study using 2.45 GHz radiation (WiFi frequency) found no changes in heart electrical conduction velocity in frog cardiac tissue. The research tested exposure levels significantly higher than typical human WiFi exposure without observing harmful effects.
Frog heart tissue showed no electrical conduction changes after 2 hours of continuous 2.45 GHz microwave exposure in laboratory conditions. The 1994 research tested this specific duration at various power levels without detecting any significant biological impacts.
The 1994 frog heart study tested multiple power levels of 2.45 GHz radiation, including exposures much higher than typical human wireless device levels. None of the tested power levels produced any measurable changes in cardiac electrical conduction velocity.