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Brain & Nervous System

Effect of long-term (2 years) exposure of mouse brains to global system for mobile communication (GSM) radiofrequency fields on astrocytic immunoreactivity.

No Effects Found

Court-Kowalski S, Finnie JW, Manavis J, Blumbergs PC, Helps SC, Vink R. · 2015

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Two years of high-level cell phone radiation exposure produced no detectable brain cell activation in mice, even at levels exceeding typical phone use.

Plain English Summary

Summary written for general audiences

Researchers exposed mice to cell phone radiation (900 MHz) at high levels (4 W/kg SAR) for five days per week over two full years, then examined their brains for signs of astrocyte activation - a cellular response that indicates brain injury or stress. They found no detectable changes in these protective brain cells compared to unexposed mice, suggesting this level of radiofrequency exposure did not trigger measurable brain inflammation or damage.

Why This Matters

This study provides reassuring evidence that chronic exposure to GSM radiation at 4 W/kg SAR - a level significantly higher than typical cell phone use (which averages 0.5-1.5 W/kg) - did not produce detectable astrocytic activation in mouse brains. Astrocytes are sentinel cells that respond to brain injury, inflammation, and stress, making them sensitive indicators of neural damage. The researchers used rigorous methodology including proper controls and a clinically relevant exposure duration spanning the majority of a mouse's lifespan. While this finding doesn't eliminate all concerns about RF exposure effects on the brain, it suggests that the specific mechanism of astrocytic inflammation may not be triggered at these exposure levels. What this means for you: the absence of astrocytic activation at exposure levels exceeding typical phone use provides some confidence that everyday cell phone radiation may not be causing this particular type of brain cell stress response.

Exposure Details

SAR
4 W/kg
Source/Device
900 MHz
Exposure Duration
Five successive days per week for 104 weeks

Exposure Context

This study used 4 W/kg for SAR (device absorption):

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: 4 W/kgExtreme Concern - 0.1 W/kgFCC Limit - 1.6 W/kgEffects observed in the Extreme Concern range (Building Biology)This level is 3 times the FCC limit
A logarithmic frequency spectrum from 10 Hz to 100 GHz showing where this study's 900 MHz exposure sits relative to common EMF sources.Where This Frequency Sits on the EMF SpectrumELFVLFLF / MFHF / VHFUHFSHFmm10 Hz100 GHzThis study: 900 MHzPower lines50/60 Hz5G mm28 GHzLogarithmic scale

Study Details

This study was designed to determine whether long-term (2 years) brain exposure to mobile telephone radiofrequency (RF) fields produces any astrocytic activation as these glia react to a wide range of neural perturbations by astrogliosis.

Using a purpose-designed exposure system at 900 MHz, mice were given a single, far-field whole body ...

There was no change in astrocytic GFAP immunostaining in brains after long-term exposure to mobile t...

It was concluded that long-term (2 years) exposure of murine brains to mobile telephone RF fields did not produce any astrocytic reaction (astrogliosis) detectable by GFAP immunostaining.

Cite This Study
Court-Kowalski S, Finnie JW, Manavis J, Blumbergs PC, Helps SC, Vink R. (2015). Effect of long-term (2 years) exposure of mouse brains to global system for mobile communication (GSM) radiofrequency fields on astrocytic immunoreactivity. Bioelectromagnetics. 2015 Feb 20. doi: 10.1002/bem.21891.
Show BibTeX
@article{s_2015_effect_of_longterm_2_2989,
  author = {Court-Kowalski S and Finnie JW and Manavis J and Blumbergs PC and Helps SC and Vink R.},
  title = {Effect of long-term (2 years) exposure of mouse brains to global system for mobile communication (GSM) radiofrequency fields on astrocytic immunoreactivity.},
  year = {2015},
  
  url = {https://pubmed.ncbi.nlm.nih.gov/25703451/},
}
PubMed: 25703451

Cited By (11 papers)

Quick Questions About This Study

A 2015 study exposed mice to 900 MHz cell phone radiation at 4 W/kg SAR for two years and found no astrocyte activation. Researchers detected no changes in GFAP immunostaining, indicating the radiation did not trigger measurable brain inflammation or protective cell responses.
Research using 4 W/kg SAR exposure (well above typical phone levels) for two years showed no brain cell damage in mice. The study found no astrocytic reactions or GFAP changes, suggesting even high-intensity 900 MHz radiation didn't cause detectable brain injury.
After exposing mice to GSM 900 MHz radiation five days weekly for two years, researchers found no changes in brain astrocytes. GFAP immunostaining remained identical between exposed and control groups, indicating no astrogliosis or brain stress response occurred.
A two-year study found no brain inflammation in mice exposed to 900 MHz radiation at 4 W/kg SAR. Researchers specifically examined astrocyte activation using GFAP markers and detected no inflammatory responses compared to unexposed control animals.
Court-Kowalski's 2015 research showed brain protective cells (astrocytes) remained unaffected after two years of 900 MHz exposure in mice. The study found no astrocytic immunoreactivity changes, suggesting these crucial brain support cells weren't impacted by chronic radiation.