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Changes in synaptic efficacy in rat brain slices following extremely low-frequency magnetic field exposure at embryonic and early postnatal age

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Balassa T, Varró P, Elek S, Drozdovszky O, Szemerszky R, Világi I, Bárdos G. · 2013

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Magnetic field exposure during brain development altered neural communication and memory formation in developing rats at levels found near power infrastructure.

Plain English Summary

Summary written for general audiences

Researchers exposed pregnant and newborn rats to 50 Hz magnetic fields (household electricity frequency) during brain development. The exposure altered how brain cells communicate, increasing electrical activity but impairing the brain's ability to form new memories and connections during critical developmental periods.

Why This Matters

This study reveals concerning effects on developing brains from magnetic field exposures that occur during the most vulnerable periods of neural development. The researchers used exposure levels of 0.5 to 3 mT, which are significantly higher than typical household exposures (around 0.01-0.1 mT near appliances) but within ranges found near power lines or certain occupational settings. What makes this research particularly significant is that it demonstrates measurable changes to synaptic plasticity, the fundamental process by which our brains learn and form memories. The timing of exposure proved critical, with different developmental windows showing distinct vulnerability patterns. This adds to a growing body of evidence suggesting that EMF exposure during pregnancy and early infancy may pose unique risks to neurological development that don't exist for adult exposure.

Exposure Details

Magnetic Field
0.5 and 3 mG
Source/Device
50 Hz
Exposure Duration
in utero during the second gestation week or as newborns for 7 days starting 3 days after birth

Exposure Context

This study used 0.5 and 3 mG for magnetic fields:

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: 0.5 and 3 mGExtreme Concern5 mGFCC Limit2,000 mGEffects observed in the Slight Concern range (Building Biology)FCC limit is 4,000x higher than this exposure level

Study Details

The aim of the present study was to determine the effects of a long-term ELF-MF (0.5 and 3 mT, 50 Hz) exposure on synaptic functions in the developing brain.

Rats were treated with chronic exposure to MF during two critical periods of brain development, i.e....

We demonstrated that the basic excitability of hippocampal slices (measured as amplitude of populati...

Results demonstrated that ELF-MF has significant effects on basic neuronal functions and synaptic plasticity in brain slice preparations originating from rats exposed either in fetal or in newborn period.

Cite This Study
Balassa T, Varró P, Elek S, Drozdovszky O, Szemerszky R, Világi I, Bárdos G. (2013). Changes in synaptic efficacy in rat brain slices following extremely low-frequency magnetic field exposure at embryonic and early postnatal age Int J Dev Neurosci. 31(8):724-730, 2013.
Show BibTeX
@article{t_2013_changes_in_synaptic_efficacy_222,
  author = {Balassa T and Varró P and Elek S and Drozdovszky O and Szemerszky R and Világi I and Bárdos G.},
  title = {Changes in synaptic efficacy in rat brain slices following extremely low-frequency magnetic field exposure at embryonic and early postnatal age},
  year = {2013},
  
  url = {https://www.sciencedirect.com/science/article/abs/pii/S0736574813001184},
}

Quick Questions About This Study

Researchers exposed pregnant and newborn rats to 50 Hz magnetic fields (household electricity frequency) during brain development. The exposure altered how brain cells communicate, increasing electrical activity but impairing the brain's ability to form new memories and connections during critical developmental periods.