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

Peripheral Blood Flow Measurements During Application of Pulsed High Frequency Currents

Bioeffects Seen

William James Erdman II · 1960

Share:

1960 research showed pulsed radiofrequency currents measurably altered human blood circulation, demonstrating early evidence of RF biological effects.

Plain English Summary

Summary written for general audiences

This 1960 study by William James Erdman II investigated how pulsed high-frequency radiofrequency currents affect blood circulation in human subjects, using plethysmograph measurements to track peripheral blood flow changes. The research examined the biological effects of short-wave diathermy treatments, which use RF energy to generate heat in body tissues. This early work documented measurable physiological responses to RF exposure, contributing to our understanding of how electromagnetic fields interact with human circulatory systems.

Why This Matters

This 1960 research represents some of the earliest documented evidence that radiofrequency fields produce measurable biological effects in humans, specifically changes to blood circulation patterns. What makes this study particularly significant is that it demonstrated clear physiological responses to RF exposure using objective measurement techniques, not just subjective reports. The fact that pulsed high-frequency currents could alter peripheral blood flow suggests these electromagnetic fields were interacting with fundamental biological processes at the cellular and vascular level.

While this study examined therapeutic RF applications rather than everyday exposures, the findings raise important questions about how modern wireless devices might affect our circulatory systems. Today's cell phones, WiFi routers, and other wireless technologies operate at similar frequencies but with different modulation patterns. The reality is that if therapeutic RF could measurably change blood flow in 1960, we need to seriously consider what chronic, low-level exposure from our wireless devices might be doing to our vascular health over time.

Exposure Information

A logarithmic frequency spectrum from 10 Hz to 100 GHz showing where this study's 27.12 MHz exposure sits relative to common EMF sources.Where This Frequency Sits on the EMF SpectrumELFVLFLF / MFHF / VHFUHFSHFmm10 Hz100 GHzThis study: 27.12 MHzPower lines50/60 HzCell phones~1 GHzWiFi2.4 GHz5G mm28 GHzLogarithmic scale

Specific exposure levels were not quantified in this study. Duration: 20 to 40 minutes per case

Study Details

To study the effect on peripheral blood flow measurements in the feet of 20 normal young adults when short-wave pulses are applied over the epigastrium.

Twenty subjects varying in age from 25 to 38 years in a fasting state were permitted to lie supine u...

Noticeable volumetric changes, indicative of increased blood flow, occurred during application in al...

Increasing peripheral blood flow without demonstrable pyrexia has desirable results. Many patients with vasospastic or vaso-occlusive disease in the lower extremities have been treated with abdominal shortwave diathermy or microwave in order to achieve reflex vasodilatation. Occasionally there were good results, but frequently the treatment was stopped because of general body heating. It could offer an explanation of the mechanics whereby body defenses are mobilized. In normal subjects we have shown that it is possible to produce an increased pulse tracing in the extremities during the application of pulsed high-frequency currents without any significant pyrexia.

Cite This Study
William James Erdman II (1960). Peripheral Blood Flow Measurements During Application of Pulsed High Frequency Currents.
Show BibTeX
@article{peripheral_blood_flow_measurements_during_application_of_pulsed_high_frequency_c_g7405,
  author = {William James Erdman II},
  title = {Peripheral Blood Flow Measurements During Application of Pulsed High Frequency Currents},
  year = {1960},
  
  
}
No DOI on file for this study.

Quick Questions About This Study

Plethysmograph devices measure blood volume changes in tissues by detecting pressure variations. In this study, these sensitive instruments detected measurable changes in peripheral blood flow when subjects were exposed to pulsed high-frequency radiofrequency currents, providing objective evidence of biological responses.
Short-wave diathermy uses radiofrequency energy to generate controlled heating in body tissues. This 1960 research found that these RF treatments produced detectable changes in peripheral blood flow patterns, suggesting the electromagnetic fields were influencing vascular function beyond just thermal effects.
Pulsed RF currents deliver electromagnetic energy in intermittent bursts rather than continuously. This approach allows researchers to study biological responses during both exposure and recovery periods, helping distinguish between immediate RF effects and longer-term physiological adaptations in blood flow patterns.
Peripheral blood flow reflects how well circulation reaches extremities like hands and feet. Changes in this measurement can indicate broader effects on cardiovascular function, making it a valuable biomarker for studying how electromagnetic fields might influence the circulatory system.
While this study examined therapeutic RF applications, it demonstrated that radiofrequency fields can produce measurable biological effects on human circulation. This raises important questions about potential vascular impacts from chronic exposure to modern wireless devices operating at similar frequencies.