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Sleep & Circadian Rhythm

Effects of electromagnetic fields emitted by mobile phones (GSM 900 and WCDMA/UMTS) on the macrostructure of sleep

No Effects Found

Danker-Hopfe H, Dorn H, Bahr A, Anderer P, Sauter C · 2011

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Cell phone radiation at safety limits didn't disrupt sleep in healthy young men, but real-world intermittent exposure patterns weren't tested.

Plain English Summary

Summary written for general audiences

German researchers exposed 30 young men to cell phone radiation at maximum power levels (2 W/kg SAR) for 8 hours nightly while they slept, testing both older GSM and newer 3G signals. They found no meaningful effects on sleep quality or architecture across multiple measured variables. The study suggests that cell phone radiation at current safety limits doesn't disrupt normal sleep patterns.

Why This Matters

This study addresses a common concern about cell phones and sleep disruption, but it has significant limitations that affect its real-world relevance. The research only included young, healthy males aged 18-30, yet sleep sensitivity to EMF exposure may vary significantly across age groups, genders, and health conditions. More importantly, the study used continuous 8-hour exposures at maximum power levels, which doesn't reflect typical phone usage patterns where people check devices intermittently throughout the night. While the researchers found no sleep disruption at 2 W/kg SAR (the current safety limit), this doesn't account for non-thermal biological effects that may occur at much lower exposure levels. The study also didn't measure sleep quality indicators like melatonin production or examine whether participants experienced more subtle changes in sleep restoration that standard sleep architecture measurements might miss.

Exposure Details

SAR
2 W/kg
Source/Device
Mobile Phones:900 MHz GSM and WCDMA/UMTS
Exposure Duration
3 nights of 8 h

Exposure Context

This study used 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: 2 W/kgExtreme Concern - 0.1 W/kgFCC Limit - 1.6 W/kgEffects observed in the Extreme Concern range (Building Biology)This level is 1 times the FCC limit
A logarithmic frequency spectrum from 10 Hz to 100 GHz showing where this study's 900 MHz exposure sits relative to common EMF sources.Where This Frequency Sits on the EMF SpectrumELFVLFLF / MFHF / VHFUHFSHFmm10 Hz100 GHzThis study: 900 MHzPower lines50/60 Hz5G mm28 GHzLogarithmic scale

Study Details

In the present double‐blind, randomized, sham‐controlled cross‐over study, possible effects of electromagnetic fields emitted by Global System for Mobile Communications (GSM) 900 and Wideband Code‐Division Multiple Access (WCDMA)/Universal Mobile Telecommunications System (UMTS) cell‐phones on the macrostructure of sleep were investigated in a laboratory environment

An adaptation night, which served as screening night for sleep disorders and as an adjustment night ...

Thirteen of 177 variables characterizing the initiation and maintenance of sleep in the GSM 900 and ...

From the present results there is no evidence for a sleep-disturbing effect of GSM 900 and WCDMA exposure.

Cite This Study
Danker-Hopfe H, Dorn H, Bahr A, Anderer P, Sauter C (2011). Effects of electromagnetic fields emitted by mobile phones (GSM 900 and WCDMA/UMTS) on the macrostructure of sleep J Sleep Res. 20(1 Pt 1):73-81, 2011.
Show BibTeX
@article{h_2011_effects_of_electromagnetic_fields_2746,
  author = {Danker-Hopfe H and Dorn H and Bahr A and Anderer P and Sauter C},
  title = {Effects of electromagnetic fields emitted by mobile phones (GSM 900 and WCDMA/UMTS) on the macrostructure of sleep},
  year = {2011},
  doi = {10.1111/j.1365-2869.2010.00850.x},
  url = {https://onlinelibrary.wiley.com/doi/full/10.1111/j.1365-2869.2010.00850.x},
}
DOI: 10.1111/j.1365-2869.2010.00850.x

Cited By (38 papers)

View all 38 citing papers on Semantic Scholar

Quick Questions About This Study

A 2011 German study exposed 30 young men to maximum cell phone radiation levels (2 W/kg SAR) for 8 hours nightly and found no meaningful effects on sleep quality or architecture. The research suggests current safety limits don't disrupt normal sleep patterns.
Research comparing GSM 900 MHz and newer 3G WCDMA signals found no significant sleep disruption from either technology. The study exposed participants to both signal types at maximum power levels throughout the night with minimal effects detected.
German researchers measured 177 sleep variables and found only 13 changed with GSM 900 exposure and 3 with WCDMA exposure. The few significant results were not considered indicative of negative sleep impact by the study authors.
A controlled study of 30 young men exposed to maximum cell phone radiation levels throughout sleep found no evidence of sleep-disturbing effects. Both older GSM and newer 3G technologies showed minimal impact on sleep initiation and maintenance.
Research testing cell phone radiation at maximum power levels (2 W/kg SAR) found no significant effects on sleep initiation or maintenance. The 8-hour nightly exposures to both GSM 900 and WCDMA signals showed no meaningful sleep disruption.