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Sleep & Circadian Rhythm

The dielectric properties of human pineal gland tissue and RF absorption due to wireless communication devices in the frequency range 400-1850 MHz.

No Effects Found

Schmid G, Uberbacher R, Samaras T, Tschabitscher M, Mazal PR. · 2007

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Cell phones deliver only microscopic amounts of RF energy to the pineal gland, making thermal damage to this sleep-regulating brain structure highly unlikely.

Plain English Summary

Summary written for general audiences

Researchers measured how much radiofrequency energy from cell phones actually reaches the pineal gland, a small brain structure that produces melatonin and regulates sleep cycles. Using tissue samples from 20 human pineal glands and computer modeling, they found that even when a phone operates at maximum power next to your ear, only tiny amounts of RF energy (11 microwatts) are absorbed by this deep brain structure. The scientists concluded that cell phone radiation is unlikely to cause temperature-related effects in the pineal gland.

Study Details

In order to enable a detailed analysis of radio frequency (RF) absorption in the human pineal gland, the dielectric properties of a sample of 20 freshly removed pineal glands were measured less than 20 h after death.

Furthermore, a corresponding high resolution numerical model of the brain region surrounding the pin...

For typical output power values of real handheld mobile communication devices, the obtained results ...

These results indicate that temperature-related biologically relevant effects on the pineal gland induced by the RF emissions of typical handheld mobile communication devices are unlikely.

Cite This Study
Schmid G, Uberbacher R, Samaras T, Tschabitscher M, Mazal PR. (2007). The dielectric properties of human pineal gland tissue and RF absorption due to wireless communication devices in the frequency range 400-1850 MHz. Phys Med Biol. 52(17):5457-5468, 2007.
Show BibTeX
@article{g_2007_the_dielectric_properties_of_3371,
  author = {Schmid G and Uberbacher R and Samaras T and Tschabitscher M and Mazal PR.},
  title = {The dielectric properties of human pineal gland tissue and RF absorption due to wireless communication devices in the frequency range 400-1850 MHz.},
  year = {2007},
  
  url = {https://pubmed.ncbi.nlm.nih.gov/17762098/},
}
PubMed: 17762098

Cited By (12 papers)

Quick Questions About This Study

A 2007 study found that even when a 500mW cell phone operates at maximum power next to your ear, only 11 microwatts of RF energy reach the pineal gland. This tiny amount is far below levels that could cause temperature-related biological effects in this sleep-regulating brain structure.
Yes, research shows 400 MHz causes the highest RF absorption in the pineal gland compared to typical mobile frequencies. However, even at this frequency with maximum phone power, absorption remains extremely low at just 11 microwatts in the 96-milligram pineal gland tissue.
The 2007 tissue study found 1850 MHz phones produce 36 times less RF absorption in the pineal gland compared to 400 MHz, and significantly less than 900 MHz frequencies. All tested frequencies showed absorption levels too low to cause temperature-related biological effects.
No, computer modeling using actual human pineal gland tissue found that typical cell phone radiation produces only microwatts of absorbed power in this gland. Researchers concluded these tiny energy levels are unlikely to cause any temperature-related effects on melatonin production.
Austrian researchers analyzed 20 human pineal gland samples and found RF absorption from typical mobile phones remains far below international safety standards. Even maximum-power devices produced absorption levels thousands of times smaller than established SAR limits for biological effects.