8,700 Studies Reviewed. 87.0% Found Biological Effects. The Evidence is Clear.
Shield Your Body
Brain & Nervous System

Exposure to an 890-MHz mobile phone-like signal and serum levels of S100B and transthyretin in volunteers.

Bioeffects Seen

Söderqvist F, Carlberg M, Hansson Mild K, Hardell L · 2009

View Original Abstract
Share:

Cell phone radiation compromised blood-brain barrier markers in humans after just 30 minutes at typical phone exposure levels.

Plain English Summary

Summary written for general audiences

Researchers exposed 41 volunteers to cell phone radiation for 30 minutes and measured blood markers that indicate whether the blood-brain barrier (the protective shield around your brain) had been compromised. They found that one marker called transthyretin increased significantly after exposure, suggesting the radiation may have affected this critical barrier. This is concerning because a compromised blood-brain barrier could allow harmful substances to enter the brain more easily.

Why This Matters

This study represents groundbreaking research because it's the first to directly test whether cell phone radiation affects the human blood-brain barrier. The blood-brain barrier is your brain's security system, preventing toxins and other harmful substances from entering brain tissue. The fact that researchers found measurable changes in barrier integrity markers after just 30 minutes of exposure at 1.0 W/kg SAR (similar to what your phone produces during a call) should raise serious questions about long-term effects. While the researchers acknowledge they don't know the clinical significance of this finding, the reality is that any compromise to the blood-brain barrier represents a potential pathway for neurological harm. The science demonstrates that even short-term EMF exposure can produce measurable biological changes in one of your body's most critical protective systems.

Exposure Details

SAR
1 W/kg
Source/Device
890-MHz mobile phone
Exposure Duration
30 min

Exposure Context

This study used 1 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 W/kgExtreme Concern - 0.1 W/kgFCC Limit - 1.6 W/kgEffects observed in the Extreme Concern rangeFCC limit is 2x higher than this level
A logarithmic frequency spectrum from 10 Hz to 100 GHz showing where this study's 890 MHz exposure sits relative to common EMF sources.Where This Frequency Sits on the EMF SpectrumELFVLFLF / MFHF / VHFUHFSHFmm10 Hz100 GHzThis study: 890 MHzPower lines50/60 Hz5G mm28 GHzLogarithmic scale

Study Details

The aim of this study was to test, using peripheral markers, whether exposure to a mobile phone-like signal alters the integrity of the human blood-brain and blood-cerebrospinal fluid barriers.

A provocation study was carried out that exposed 41 volunteers to a 30 min GSM 890 MHz signal with a...

Repeated blood sampling before and after the provocation showed no statistically significant increas...

Cite This Study
Söderqvist F, Carlberg M, Hansson Mild K, Hardell L (2009). Exposure to an 890-MHz mobile phone-like signal and serum levels of S100B and transthyretin in volunteers. Toxicol Lett. 189(1):63-66, 2009.
Show BibTeX
@article{f_2009_exposure_to_an_890mhz_1331,
  author = {Söderqvist F and Carlberg M and Hansson Mild K and Hardell L},
  title = {Exposure to an 890-MHz mobile phone-like signal and serum levels of S100B and transthyretin in volunteers.},
  year = {2009},
  
  url = {https://pubmed.ncbi.nlm.nih.gov/19427372/},
}
PubMed: 19427372

Cited By (20 papers)

Quick Questions About This Study

A 2009 study found that 30 minutes of 890 MHz cell phone radiation exposure significantly increased transthyretin levels in volunteers' blood, suggesting potential blood-brain barrier disruption. This protective brain barrier normally prevents harmful substances from entering brain tissue, making this finding concerning for regular phone users.
Transthyretin is a blood protein that increases when the blood-brain barrier becomes compromised. In the 890 MHz exposure study, transthyretin levels rose significantly 60 minutes after cell phone radiation exposure, indicating the brain's protective barrier may have been weakened by the electromagnetic fields.
Research using 890 MHz signals showed transthyretin increases appeared 60 minutes after a 30-minute phone exposure ended, not immediately afterward. This delayed response suggests the blood-brain barrier effects from cell phone radiation may develop gradually rather than instantly during phone calls.
No, the 890 MHz mobile phone study found no statistically significant increase in S100B protein levels after 30 minutes of exposure. However, transthyretin levels did increase significantly, indicating different blood-brain barrier proteins respond differently to cell phone radiation exposure.
Scientists measure proteins like transthyretin and S100B in blood samples to detect blood-brain barrier damage from cell phone radiation. The 890 MHz study showed transthyretin increases significantly after exposure, while S100B remained unchanged, suggesting selective barrier effects from electromagnetic fields.