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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 ContextA logarithmic scale showing exposure levels relative to Building Biology concern thresholds and regulatory limits.Study Exposure Level in ContextThis study: 0.0016 and 0.0044 W/kgExtreme Concern0.1 W/kgFCC Limit1.6 W/kgEffects observed in the Slight Concern range (Building Biology)FCC limit is 1,000x higher than this exposure level

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/},
}

Quick Questions About This Study

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.