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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

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

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One month of cell phone-level radiation caused measurable brain damage in mice, with protective proteins declining and injury markers increasing.

Plain English Summary

Summary written for general audiences

Researchers exposed mice to cell phone-level radiofrequency radiation (835 MHz) for one month at power levels similar to what phones emit during calls. They found significant damage to brain cells in the hippocampus, the brain region critical for memory and learning, including loss of protective proteins and signs of brain injury that worsened at higher exposure levels.

Why This Matters

This study provides compelling evidence that radiofrequency radiation at levels comparable to cell phone use can cause measurable brain damage within just one month of exposure. The 1.6 W/kg exposure level falls within the range of typical cell phone SAR values (which legally can reach up to 2.0 W/kg), making these findings directly relevant to everyday phone use. The researchers documented both the loss of calcium-binding proteins that protect neurons and increased markers of brain injury, with damage escalating at higher power levels. What makes this research particularly significant is that it demonstrates biological harm at exposure levels the wireless industry and regulators claim are safe. The hippocampus damage observed here could have implications for memory, learning, and cognitive function. While this is an animal study, the biological mechanisms involved are fundamental to mammalian brain function, suggesting similar risks may exist for humans.

Exposure Details

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

Exposure Context

This study used 1.6 and 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 and 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 examine 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 distr...

E4 group showed a prominent decrement in CB and CR IR than the E1.6 group due to down-regulation of ...

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 835 MHz radiofrequency at SAR values of 1.6 and 4.0 W/kg Neurosci Lett. 506(2):292-296, 2012.
Show BibTeX
@article{d_2012_calciumbinding_proteins_and_gfap_139,
  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 835 MHz radiofrequency at SAR values of 1.6 and 4.0 W/kg},
  year = {2012},
  
  url = {https://www.sciencedirect.com/science/article/abs/pii/S0304394011015473},
}

Quick Questions About This Study

Yes, a 2012 study found that 835 MHz radiation at cell phone power levels caused significant damage to the hippocampus, the brain's memory center. Mice exposed for one month showed loss of protective proteins and signs of brain injury that worsened at higher exposure levels.
Research shows one month of 835 MHz radiation exposure can cause brain cell death in the hippocampus. The study found decreased calcium-binding proteins that protect neurons, leading to cell death, with more severe damage occurring at higher radiation power levels.
Brain astrocytes showed increased GFAP protein and morphological changes after 835 MHz radiation exposure, indicating brain injury. These glial cells, which support neurons, became more reactive at higher power levels, suggesting the brain was responding to radiation-induced damage.
Yes, higher SAR levels cause more hippocampal damage. The study found that 4.0 W/kg SAR caused significantly more protein loss, neuronal death, and astrocyte activation in the hippocampus compared to 1.6 W/kg SAR exposure.
835 MHz radiation disrupts calcium regulation by reducing calcium-binding proteins in hippocampal neurons. This impairs the brain's ability to buffer calcium levels, which can lead to cell death when calcium homeostasis is disrupted in memory-critical brain regions.