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Brain & Nervous System107 citations

Effects of low intensity radiofrequency electromagnetic fields on electrical activity in rat hippocampal slices.

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Tattersall JE, Scott IR, Wood SJ, Nettell JJ, Bevir MK, Wang Z, Somasiri NP, Chen X. · 2001

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Brain tissue shows measurable electrical changes from RF radiation at levels 500 times lower than current cell phone safety limits.

Plain English Summary

Summary written for general audiences

Researchers exposed rat brain tissue to cell phone-frequency radiation at 700 MHz and found it altered brain cell electrical activity by up to 120%, even at extremely low power levels that caused no heating, suggesting the brain responds to radiofrequency fields through non-thermal biological mechanisms.

Why This Matters

This study provides compelling evidence that radiofrequency radiation can directly affect brain function at power levels well below current safety standards. The researchers used SAR levels between 0.0016 and 0.0044 W/kg, which are significantly lower than the 2 W/kg limit for cell phones in the US. What makes this research particularly significant is that it demonstrates clear biological effects without any temperature increase, challenging the long-held assumption that RF radiation is only harmful when it heats tissue. The hippocampus plays a central role in memory formation and cognitive function, so alterations in its electrical activity could have real-world implications for learning, memory, and overall brain health. The fact that 36% of brain tissue samples showed reduced seizure activity also suggests RF fields can have varied and unpredictable effects on neural circuits.

Exposure Details

SAR
0.0016 and 0.0044 W/kg
Electric Field
25.2-71.0 V/m
Source/Device
700 MHz
Exposure Duration
5-15 min

Exposure Context

This study used 25.2-71.0 V/m for electric fields:

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: 0.0016 and 0.0044 W/kgExtreme Concern - 0.1 W/kgFCC Limit - 1.6 W/kgEffects observed in the Slight Concern rangeFCC limit is 1,000x higher than this level
A logarithmic frequency spectrum from 10 Hz to 100 GHz showing where this study's 700 MHz exposure sits relative to common EMF sources.Where This Frequency Sits on the EMF SpectrumELFVLFLF / MFHF / VHFUHFSHFmm10 Hz100 GHzThis study: 700 MHzPower lines50/60 HzWiFi2.4 GHz5G mm28 GHzLogarithmic scale

Study Details

To investigate the effects of low intensity radiofrequency electromagnetic fields on electrical activity in rat hippocampal slices

Slices of rat hippocampus were exposed to 700 MHz continuous wave radiofrequency (RF) fields (25.2-7...

Measurements with a Luxtron fibreoptic probe confirmed that there was no detectable temperature chan...

These results suggest that low-intensity RF fields can modulate the excitability of hippocampal tissue in vitro in the absence of gross thermal effects. The changes in excitability may be consistent with reported behavioural effects of RF fields.

Cite This Study
Tattersall JE, Scott IR, Wood SJ, Nettell JJ, Bevir MK, Wang Z, Somasiri NP, Chen X. (2001). Effects of low intensity radiofrequency electromagnetic fields on electrical activity in rat hippocampal slices. Brain Res 904(1):43-53, 2001.
Show BibTeX
@article{je_2001_effects_of_low_intensity_1353,
  author = {Tattersall JE and Scott IR and Wood SJ and Nettell JJ and Bevir MK and Wang Z and Somasiri NP and Chen X.},
  title = {Effects of low intensity radiofrequency electromagnetic fields on electrical activity in rat hippocampal slices.},
  year = {2001},
  
  url = {https://pubmed.ncbi.nlm.nih.gov/11516410/},
}
PubMed: 11516410

Cited By (107 papers)

View all 107 citing papers on Semantic Scholar

Quick Questions About This Study

Yes, a 2001 study found that 700 MHz radiation altered rat hippocampal brain tissue electrical activity by up to 120% without causing any detectable temperature change. The researchers confirmed no heating occurred during 15-minute exposures, suggesting non-thermal biological effects.
Research on rat brain slices showed that extremely low power 700 MHz radiofrequency fields significantly modified brain cell electrical activity even at intensities that caused no tissue heating. The changes occurred through non-thermal biological mechanisms in hippocampal tissue.
Rat hippocampal brain tissue exposed to 700 MHz electromagnetic fields showed electrical activity changes of up to 120%. These dramatic alterations occurred at low intensities without any measurable temperature increase, demonstrating significant non-thermal biological responses.
No, researchers found that imposed temperature changes up to 1°C failed to reproduce the effects seen from 700 MHz radiofrequency exposure. This proves the brain tissue changes resulted from non-thermal electromagnetic field interactions, not heating effects.
The 2001 study suggested that observed changes in rat hippocampal tissue excitability from 700 MHz exposure may be consistent with reported behavioral effects of radiofrequency fields, indicating potential real-world implications for brain function and behavior.