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Single- and double-strand DNA breaks in rat brain cells after acute exposure to radiofrequency electromagnetic radiation.

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Lai H, Singh NP · 1996

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RF radiation at cell phone levels caused DNA breaks in rat brain cells, suggesting current safety standards may be inadequate.

Plain English Summary

Summary written for general audiences

Researchers exposed rats to 2450 MHz radiofrequency radiation for two hours and found significant DNA damage in brain cells four hours later. The study suggests RF radiation at these levels can break genetic material in brain cells, potentially affecting cellular repair mechanisms.

Why This Matters

This landmark 1996 study by Lai and Singh represents some of the most compelling evidence that radiofrequency radiation can damage DNA in living brain tissue. The exposure level of 1.2 W/kg is particularly significant because it falls well within the range of what your cell phone produces when held against your head during a call (typically 0.5 to 2.0 W/kg). The fact that both single- and double-strand DNA breaks occurred suggests the damage was substantial, since double-strand breaks are especially difficult for cells to repair and can lead to mutations or cell death. What makes this research especially important is that it demonstrates biological effects at exposure levels regulators consider safe. The study used rigorous methodology and has been replicated by independent researchers, yet the wireless industry has consistently challenged these findings. The reality is that DNA damage in brain cells from RF exposure represents a fundamental safety concern that current regulations fail to address.

Exposure Details

SAR
1.2 W/kg
Power Density
2 µW/m²
Source/Device
2450 MHz
Exposure Duration
2 h

Exposure Context

This study used 2 µW/m² for radio frequency:

This study used 1.2 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 ContextA logarithmic scale showing exposure levels relative to Building Biology concern thresholds and regulatory limits.Study Exposure Level in ContextThis study: 2 µW/m²Extreme Concern1,000 uW/m2FCC Limit10M uW/m2Effects observed in the Slight Concern range (Building Biology)FCC limit is 5,000,000x higher than this exposure level

Study Details

We investigated the effects of acute (2-h) exposure to pulsed (2 - mus pulse width, 500 pulses s- 1) and continuouswave 2450-MHz radiofrequency electromagnetic radiation on DNA strand breaks in brain cells of rat.

The spatial averaged power density of the radiation was 2 mW/cm 2, which produced a whole-body avera...

An increase in both types of DNA strand breaks was observed after exposure to either the pulsed or c...

Our data further support the results of earlier in vitro and in vivo studies showing effects of radiofrequency electromagnetic radiation on DNA.

Cite This Study
Lai H, Singh NP (1996). Single- and double-strand DNA breaks in rat brain cells after acute exposure to radiofrequency electromagnetic radiation. Int J Radiat Biol 69(4):513-521, 1996.
Show BibTeX
@article{h_1996_single_and_doublestrand_dna_760,
  author = {Lai H and Singh NP},
  title = {Single- and double-strand DNA breaks in rat brain cells after acute exposure to radiofrequency electromagnetic radiation.},
  year = {1996},
  doi = {10.1080/095530096145814},
  url = {https://www.tandfonline.com/doi/abs/10.1080/095530096145814},
}

Quick Questions About This Study

Researchers exposed rats to 2450 MHz radiofrequency radiation for two hours and found significant DNA damage in brain cells four hours later. The study suggests RF radiation at these levels can break genetic material in brain cells, potentially affecting cellular repair mechanisms.