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Blood-forming system in rats after whole-body microwave exposure; reference to the lymphocytes.

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Trosic I, Busljeta I, Pavicic I. · 2004

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Microwave radiation at cell phone levels reduced immune cell production in rats after just 15 days of exposure.

Plain English Summary

Summary written for general audiences

Croatian researchers exposed rats to 2.45 GHz microwave radiation (the same frequency used by WiFi and microwave ovens) for 2 hours daily over periods up to 30 days. They found that longer exposures significantly reduced lymphoblasts, which are immature immune cells that develop into infection-fighting lymphocytes. The researchers interpreted this as a stress response in the blood-forming system, suggesting the body was adapting to the microwave exposure.

Why This Matters

This study adds to growing evidence that microwave radiation affects immune system function, even at relatively low exposure levels. The SAR levels used (1-2 W/kg) are comparable to what you experience when holding a cell phone to your head during a call. What makes this research particularly significant is that it demonstrates measurable immune system changes with chronic, low-level exposure - the kind we increasingly face in our WiFi-saturated environment. The researchers' characterization of these changes as 'adaptation' rather than harm doesn't diminish the concern. The reality is that forcing your immune system to constantly adapt to artificial radiation represents an unnecessary biological burden that could compromise your body's ability to fight infections and other health challenges.

Exposure Details

SAR
1 to 2 W/kg
Power Density
5 to 10 µW/m²
Source/Device
2.45 GHz
Exposure Duration
2, 8, 15 or 30 days, for 2 h a day, 7 days a week.

Exposure Context

This study used 5 to 10 µW/m² for radio frequency:

This study used 1 to 2 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: 5 to 10 µW/m²Extreme Concern - 1,000 uW/m2FCC Limit - 10M uW/m2Effects observed in the Slight Concern rangeFCC limit is 2,000,000x higher than this level
A logarithmic frequency spectrum from 10 Hz to 100 GHz showing where this study's 2.45 GHz exposure sits relative to common EMF sources.Where This Frequency Sits on the EMF SpectrumELFVLFLF / MFHF / VHFUHFSHFmm10 Hz100 GHzThis study: 2.45 GHzPower lines50/60 Hz5G mm28 GHzLogarithmic scale

Study Details

The influence of 2.45 GHz microwave (RF/MW) irradiation on blood-forming cells after whole-body irradiation of rats was investigated.

The exposures were conducted with a field power density of 5-10 mW/cm2, and whole-body average speci...

Significant decrease in lymphoblast count was obtained at 15 and 30th experimental day (P < 0.05), w...

The findings point out at stress response in blood-forming system in rats after selected microwave exposure, which could be considered rather as sign of adaptation than malfunction.

Cite This Study
Trosic I, Busljeta I, Pavicic I. (2004). Blood-forming system in rats after whole-body microwave exposure; reference to the lymphocytes. Toxicol Lett. 154(1-2):125-132, 2004.
Show BibTeX
@article{i_2004_bloodforming_system_in_rats_1379,
  author = {Trosic I and Busljeta I and Pavicic I.},
  title = {Blood-forming system in rats after whole-body microwave exposure; reference to the lymphocytes.},
  year = {2004},
  
  url = {https://pubmed.ncbi.nlm.nih.gov/15475186/},
}
PubMed: 15475186

Cited By (28 papers)

Quick Questions About This Study

Yes, a 2004 Croatian study found that 2.45 GHz microwave radiation (WiFi frequency) significantly reduced lymphoblast counts in rats after 15 and 30 days of 2-hour daily exposures. Lymphoblasts are immature immune cells that develop into infection-fighting lymphocytes.
Research shows that 2.45 GHz microwave radiation begins affecting immune cells after 15 days of exposure. Croatian scientists found significant reductions in lymphoblast counts after both 15 and 30 days of 2-hour daily exposures in laboratory rats.
Researchers interpreted the lymphoblast reduction as an adaptive stress response rather than harmful malfunction. The 2004 Croatian study suggested that rats' blood-forming systems were adapting to chronic 2.45 GHz microwave exposure, not experiencing immune system damage.
After 30 days of daily 2.45 GHz exposure, rats showed significantly reduced lymphoblast counts compared to unexposed controls. However, other blood parameters remained normal, suggesting the changes were specific to these immature immune cells rather than widespread blood effects.
Yes, the same 2.45 GHz frequency used in microwave ovens affected the blood-forming system in rats. Croatian researchers found that this frequency reduced lymphoblast production after chronic exposure, indicating the body's blood cell manufacturing process responds to microwave radiation.