8,655 Studies Reviewed. 86.9% Found Biological Effects. The Evidence is Clear.
Shield Your Body

Note: This study found no significant biological effects under its experimental conditions. We include all studies for scientific completeness.

Whole Body / GeneralPart of the Glaser Archive

Thermal and athermal effects of microwave radiation on the activity of glucose-6-phosphate dehydrogenase in human blood

No Effects Found

Belkhode M., Johnson DL., Muc AM. · 1974

Share:

High-power 2.8 GHz microwaves caused no enzyme damage beyond normal heating effects in this controlled study.

Plain English Summary

Summary written for general audiences

Researchers exposed human blood samples to 2.8 GHz microwave radiation at high power levels (500-1000 mW/cm²) to test whether microwaves could damage an important enzyme called glucose-6-phosphate dehydrogenase through non-thermal effects. They found that while heat from the microwaves reduced enzyme activity by up to 80%, the microwaves themselves caused no statistically significant damage beyond what heat alone would cause.

Figures from the Original Paper

Diagrams extracted from the original research document.

diagramPage 3 - Fig. 1: Schematic diagram of the apparatus.
p. 3 of the original PDF
graphPage 7 - Figure 4. Relative activity of yeast glucose-6-phosphate dehydrogenase as a function of temperature: treatment with microwave radiation and without microwave radiation.
p. 7 of the original PDF
Cite This Study
Belkhode M., Johnson DL., Muc AM. (1974). Thermal and athermal effects of microwave radiation on the activity of glucose-6-phosphate dehydrogenase in human blood.
Show BibTeX
@article{thermal_and_athermal_effects_of_microwave_radiation_on_the_activity_of_glucose_6_g6661,
  author = {Belkhode M. and Johnson DL. and Muc AM.},
  title = {Thermal and athermal effects of microwave radiation on the activity of glucose-6-phosphate dehydrogenase in human blood},
  year = {1974},
  
  
}
No DOI on file for this study.

Quick Questions About This Study

Researchers used extremely high power densities of 500-1000 mW/cm², which absorbed 230 mW/cm² into the blood samples. These levels are roughly 1000 times higher than typical cell phone exposures today.
No statistically significant damage was found beyond normal heating effects. While heat reduced enzyme activity by up to 80%, the microwaves themselves caused only a non-significant 10.4% effect.
They conducted treatments at fixed temperatures of 37°C, 56.7°C, and 80.7°C, allowing them to distinguish between damage caused by heat versus damage caused by the microwaves themselves.
It's a crucial enzyme in human blood cells that helps protect against oxidative damage. Researchers studied it because enzyme damage could indicate whether microwaves cause harmful biological effects beyond heating.
The study used two different treatment times that resulted in absorbed energies of 35 and 62 J/cm². The exact exposure durations weren't specified in the available abstract.