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Brain & Nervous System

Cognitive and physiological responses in humans exposed to a TETRA base station signal in relation to perceived electromagnetic hypersensitivity.

No Effects Found

Wallace D, Eltiti S, Ridgewell A, Garner K, Russo R, Sepulveda F, Walker S, Quinlan T, Dudley S, Maung S, Deeble R, Fox E. · 2012

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TETRA radio signals at cell tower-level exposures showed no measurable effects on brain function or physical responses, even in electromagnetically sensitive individuals.

Plain English Summary

Summary written for general audiences

Researchers tested whether TETRA radio signals (used by emergency services) affect brain function and physical responses in 183 people, including 51 who reported being sensitive to electromagnetic fields. Participants were exposed to 420 MHz signals at levels similar to living near a cell tower while performing memory and attention tests. The study found no differences in cognitive performance or physical responses between real exposure and fake exposure in either group.

Why This Matters

This study adds to a consistent pattern in the research literature on electromagnetic hypersensitivity (EHS). While many people report symptoms they attribute to EMF exposure, controlled studies like this one repeatedly fail to find measurable differences in cognitive or physiological responses during actual exposure. The 10 mW/m² exposure level used here is comparable to what you might experience living within a few hundred meters of a cell tower. What this means for you is that the science continues to show no clear evidence that typical RF exposures impair brain function or cause detectable physical responses, even in people who believe they are sensitive to EMFs. However, this doesn't dismiss the real symptoms that EHS sufferers experience - it simply suggests the cause may not be the electromagnetic fields themselves.

Exposure Details

Power Density
0.001 mW/cm²
Source/Device
420 MHz

Exposure Context

This study used 0.001 mW/cm² for radio frequency:

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 Exposure Level in ContextStudy Exposure Level in ContextThis study: 0.001 mW/cm²Extreme Concern - 1,000 µW/m²FCC Limit - 10M µW/m²Effects observed in the Extreme Concern range (Building Biology)FCC limit is 1,000 times higher than this level
A logarithmic frequency spectrum from 10 Hz to 100 GHz showing where this study's 420 MHz exposure sits relative to common EMF sources.Where This Frequency Sits on the EMF SpectrumELFVLFLF / MFHF / VHFUHFSHFmm10 Hz100 GHzThis study: 420 MHzPower lines50/60 HzWiFi2.4 GHz5G mm28 GHzLogarithmic scale

Study Details

The present study is the first to examine whether acute exposure to a TETRA base station signal has an impact on cognitive functioning and physiological response.

Participants were exposed to a 420 MHz TETRA signal at a power flux density of 10 mW/m(2) as well as...

We observed no differences in cognitive performance between sham and TETRA exposure in either group;...

These findings are similar to previous double-blind studies with other mobile phone signals (900-2100 MHz), which could not establish any clear evidence that mobile phone signals affect health or cognitive function.

Cite This Study
Wallace D, Eltiti S, Ridgewell A, Garner K, Russo R, Sepulveda F, Walker S, Quinlan T, Dudley S, Maung S, Deeble R, Fox E. (2012). Cognitive and physiological responses in humans exposed to a TETRA base station signal in relation to perceived electromagnetic hypersensitivity. Bioelectromagnetics. 33(1):23-39, 2012.
Show BibTeX
@article{d_2012_cognitive_and_physiological_responses_3482,
  author = {Wallace D and Eltiti S and Ridgewell A and Garner K and Russo R and Sepulveda F and Walker S and Quinlan T and Dudley S and Maung S and Deeble R and Fox E.},
  title = {Cognitive and physiological responses in humans exposed to a TETRA base station signal in relation to perceived electromagnetic hypersensitivity.},
  year = {2012},
  
  url = {https://pubmed.ncbi.nlm.nih.gov/21647932/},
}
PubMed: 21647932

Cited By (32 papers)

Quick Questions About This Study

A 2012 study found no evidence that TETRA radio signals (420 MHz) affect brain function. Researchers tested 183 people, including those claiming electromagnetic sensitivity, and found no differences in memory, attention, or physical responses during real versus fake exposure.
Research shows emergency service radio signals don't impair cognitive function. A controlled study exposed people to TETRA signals at levels similar to living near cell towers and found no differences in mental performance compared to sham exposure.
Studies indicate 420 MHz radiation doesn't harm memory function. When researchers tested people exposed to TETRA base station signals while performing memory tasks, they found no cognitive impairment compared to fake exposure conditions in any participants.
Scientific evidence shows TETRA exposure doesn't cause physical symptoms. A double-blind study found no differences in physiological responses between real and fake TETRA signal exposure, even among people who reported being electromagnetically hypersensitive.
Research demonstrates radio tower signals don't affect brain performance. Studies on TETRA and mobile phone frequencies consistently find no impact on cognitive function or health, with results showing no difference between real and sham exposure conditions.