Human exposure at two radio frequencies (450 and 2450 MHz): similarities and differences in physiological response.
Adair ER, Cobb BL, Mylacraine KS, Kelleher SA, · 1999
View Original AbstractHuman exposure to RF radiation above current safety limits triggers measurable physiological responses, including increased skin temperature and compensatory cooling mechanisms.
Plain English Summary
Researchers exposed 14 volunteers to radio frequency radiation at 450 and 2450 MHz (similar to cell phone frequencies) for 45 minutes at power levels exceeding current safety guidelines. The exposure caused measurable increases in skin temperature, with the body responding through increased sweating and blood flow to maintain normal core body temperature within 0.1 degrees Celsius.
Why This Matters
This study demonstrates that RF radiation at levels above current safety guidelines produces measurable physiological responses in humans, specifically thermal effects that trigger the body's cooling mechanisms. The research used SAR levels of 6.0 and 7.7 W/kg, which exceed the current FCC limit of 1.6 W/kg for cell phones by nearly four to five times. What makes this particularly relevant is that it shows biological responses occur even when the body successfully maintains thermal equilibrium. The researchers' conclusion that 'more practical dosimetry' is needed to evaluate real-world RF exposures highlights a critical gap in our current safety standards. While the study focuses on thermal effects, it provides clear evidence that RF radiation interacts with human physiology in measurable ways, supporting the need for more comprehensive research into both thermal and non-thermal biological effects of everyday wireless device use.
Exposure Details
- SAR
- 6.0 and 7.7 W/kg
- Source/Device
- 450 and 2450 MHz
- Exposure Duration
- 45-min
Exposure Context
This study used 6.0 and 7.7 W/kg for SAR (device absorption):
- 15x above the Building Biology guideline of 0.4 W/kg
Building Biology guidelines are practitioner-based limits from real-world assessments. BioInitiative Report recommendations are based on peer-reviewed science. Check Your Exposure to compare your own measurements.
Where This Falls on the Concern Scale
Study Details
The aim of this study is to observe Human exposure at two radio frequencies (450 and 2450 MHz): similarities and differences in physiological response.
Thermoregulatory responses of heat production and heat loss were measured in two different groups of...
No change in metabolic heat production occurred under any exposure conditions at either frequency. T...
The observed frequency-related response differences agree with classical data concerning the control of heat loss mechanisms in human beings. However, more practical dosimetry than is currently available will be necessary to evaluate realistic human exposures to RF energy in the natural environment.
Show BibTeX
@article{er_1999_human_exposure_at_two_793,
author = {Adair ER and Cobb BL and Mylacraine KS and Kelleher SA and},
title = {Human exposure at two radio frequencies (450 and 2450 MHz): similarities and differences in physiological response.},
year = {1999},
url = {https://pubmed.ncbi.nlm.nih.gov/10334711/},
}