8,700 Studies Reviewed. 87.0% Found Biological Effects. The Evidence is Clear.

Calcium-binding proteins and GFAP immunoreactivity alterations in murine hippocampus after 1 month of exposure to 835MHz radiofrequency at SAR values of 1.6 and 4.0W/kg.

Bioeffects Seen

Maskey D, Kim HJ, Kim HG, Kim MJ · 2012

View Original Abstract
Share:

One month of cell phone radiation exposure caused measurable brain damage in mice at levels considered safe by current regulations.

Plain English Summary

Summary written for general audiences

Researchers exposed mice to cell phone frequency radiation (835 MHz) for one month at power levels similar to heavy phone use. They found significant damage to brain cells in the hippocampus, including loss of protective calcium-binding proteins and signs of brain injury that worsened at higher exposure levels. This suggests that prolonged radiofrequency exposure may harm critical brain regions involved in memory and learning.

Why This Matters

This study provides compelling evidence that radiofrequency radiation at levels encountered during typical cell phone use can cause measurable brain damage. The SAR levels used (1.6 and 4.0 W/kg) bracket the current regulatory limit of 2.0 W/kg, meaning the lower exposure group represents what regulators consider 'safe' levels. Yet even at 1.6 W/kg, researchers observed clear signs of neuronal stress and death in the hippocampus, a brain region critical for memory formation. The dose-dependent response, where higher exposure caused more severe damage, strengthens the case for causation rather than coincidence. What makes this research particularly significant is its focus on calcium-binding proteins, which are essential for normal brain function. When these protective mechanisms fail, as shown in this study, it can lead to the kind of cellular dysfunction that underlies neurodegenerative diseases. The reality is that many people routinely expose themselves to similar or higher SAR levels through prolonged phone calls or carrying devices close to their bodies.

Exposure Details

SAR
1.6 , 4.0 W/kg
Source/Device
835MHz
Exposure Duration
1 month

Exposure Context

This study used 1.6 , 4.0 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: 1.6 , 4.0 W/kgExtreme Concern - 0.1 W/kgFCC Limit - 1.6 W/kgEffects observed in the Extreme Concern rangeFCC limit is 1x higher than this level
A logarithmic frequency spectrum from 10 Hz to 100 GHz showing where this study's 835 MHz exposure sits relative to common EMF sources.Where This Frequency Sits on the EMF SpectrumELFVLFLF / MFHF / VHFUHFSHFmm10 Hz100 GHzThis study: 835 MHzPower lines50/60 Hz5G mm28 GHzLogarithmic scale

Study Details

To investigate calcium-binding proteins and GFAP immunoreactivity alterations in murine hippocampus after 1 month of exposure to 835 MHz radiofrequency at SAR values of 1.6 and 4.0 W/kg

Different SAR values [1.6 (E1.6 group) and 4.0 (E4 group) W/kg] were applied to determine the distri...

Compared with sham control group, decreased CB and CR IRs, loss of CB and CR immunoreactive cells an...

Cite This Study
Maskey D, Kim HJ, Kim HG, Kim MJ (2012). Calcium-binding proteins and GFAP immunoreactivity alterations in murine hippocampus after 1 month of exposure to 835MHz radiofrequency at SAR values of 1.6 and 4.0W/kg. Neurosci Lett. 506(2):292-296, 2012.
Show BibTeX
@article{d_2012_calciumbinding_proteins_and_gfap_1189,
  author = {Maskey D and Kim HJ and Kim HG and Kim MJ},
  title = {Calcium-binding proteins and GFAP immunoreactivity alterations in murine hippocampus after 1 month of exposure to 835MHz radiofrequency at SAR values of 1.6 and 4.0W/kg.},
  year = {2012},
  
  url = {https://www.sciencedirect.com/science/article/abs/pii/S0304394011015473},
}

Quick Questions About This Study

Yes, a 2012 study found that one month of 835 MHz radiation exposure at cell phone power levels caused significant damage to hippocampus brain cells in mice. Researchers observed loss of protective calcium-binding proteins and signs of brain injury that worsened with higher exposure levels.
Research shows one month of 835 MHz cell phone radiation exposure damaged the hippocampus, the brain's primary memory and learning center. Mice exposed to radiation levels similar to heavy phone use showed loss of protective proteins and increased brain injury markers.
835 MHz radiation exposure significantly reduced calcium-binding proteins in mouse hippocampus cells after one month. These proteins normally protect brain cells from damage, so their loss can compromise the brain's calcium-buffering capacity and lead to cell death according to 2012 research.
Yes, higher SAR levels caused more severe brain damage in the 2012 study. Mice exposed to 4.0 W/kg showed greater loss of protective proteins and more prominent brain injury markers compared to the 1.6 W/kg group, demonstrating a dose-response relationship.
Research found that 835 MHz radiation triggered brain injury responses in mouse hippocampus after one month of exposure. Scientists observed increased GFAP protein levels and changes in brain cell structure, which are established markers of brain tissue damage and injury.