3,138 Studies Reviewed. 77.4% Found Biological Effects. The Evidence is Clear.
All Exposure Types

Magnetic Fields (ELF)

Share:

Extremely Low Frequency (ELF) magnetic fields are produced by the flow of electrical current. They are measured in milligauss (mG) or microtesla (µT). Unlike electric fields, magnetic fields easily penetrate walls and most materials.

Concern Level Thresholds

Based on Building Biology Institute guidelines (mG (milligauss)):

No Concern
< 0.2 mG
Slight Concern
0.2 – 1 mG
Severe Concern
1 – 5 mG
Extreme Concern
> 5 mG

See where common exposures fall on the scale:

Your RF Exposure in ContextA logarithmic scale showing your reading relative to Building Biology concern thresholds and FCC regulatory limits.Your RF Exposure in ContextNo ConcernSlightSevereExtreme0.215FCC Limit 0.0110,000 mG

Showing 443 studies with measured magnetic fields (elf) exposure

Changes in human EEG alpha activity following exposure to two different pulsed magnetic field sequences.

Cook CM, Saucier DM, Thomas AW, Prato FS. · 2009

Researchers exposed 32 people to weak pulsed magnetic fields (the type generated by power lines and electrical devices) for 15 minutes while measuring their brain waves. They found that different pulse patterns altered alpha brain wave activity in the back regions of the brain within just 5 minutes of exposure. The changes persisted even after exposure ended, suggesting that these everyday magnetic fields can measurably affect brain function.

Brain & Nervous SystemNo Effects Found

Pentylenetetrazol-induced seizures are not altered by pre- or post-drug exposure to a 50 Hz magnetic field.

Canseven AG, Keskil ZA, Keskil S, Seyhan N. · 2007

Researchers tested whether 50 Hz magnetic fields (the type from power lines) could affect seizures in mice, either making them better or worse. They exposed mice to magnetic fields before and after giving them a seizure-inducing drug, measuring how quickly seizures started and how long they lasted. The magnetic field exposure had no effect on seizures whatsoever, suggesting these fields don't influence brain seizure activity at the levels tested.

Brain & Nervous SystemNo Effects Found

Pentylenetetrazol-induced seizures are not altered by pre- or post-drug exposure to a 50 Hz magnetic field

Canseven AG, Keskil ZA, Keskil S, Seyhan N. · 2007

Researchers exposed mice to 50 Hz magnetic fields (the same frequency as power lines) before and after inducing seizures with a chemical drug, to see if the magnetic field exposure would affect seizure activity. They found no changes in seizure timing, duration, or death rates, suggesting that this type of magnetic field exposure doesn't influence seizure disorders. This challenges any potential therapeutic use of magnetic fields for epilepsy treatment.

Effects of extremely low frequency electromagnetic field and its combination with lead on the antioxidant system in mouse.

Liu Y, Weng E, Zhang Y, Hong R. · 2002

Researchers exposed mice to 50 Hz magnetic fields for two weeks and measured cellular damage. Higher magnetic field strengths increased harmful oxidative stress while reducing natural antioxidant defenses in brain and liver tissue, suggesting EMF exposure may compromise the body's ability to protect against cellular damage.

In vitro effects of 50 Hz magnetic fields on oxidatively damaged rabbit red blood cells.

Fiorani M et al. · 1997

Italian researchers exposed rabbit red blood cells to 50 Hz magnetic fields (the same frequency as electrical power lines) while simultaneously stressing them with oxidizing chemicals. They found that magnetic field exposure at 0.5 milliTesla made the cellular damage significantly worse, increasing enzyme breakdown by 20% and doubling the production of damaged hemoglobin compared to cells exposed to oxidative stress alone.

Effects of extremely low-frequency electromagnetic field on expression levels of some antioxidant genes in human MCF-7 cells.

Mahmoudinasab H, Sanie-Jahromi F, Saadat M · 2016

Researchers exposed breast cancer cells to 50 Hz electromagnetic fields (household electricity frequency) for 30 minutes. Stronger fields significantly altered genes that protect cells from damage, especially during on-off exposure patterns. This shows brief EMF exposure can disrupt cellular defense systems.

Changes in synaptic efficacy and seizure susceptibility in rat brain slices following extremely low‐frequency electromagnetic field exposure

Varró P, Szemerszky R, Bárdos G, Világi I. · 2009

Researchers exposed rat brain tissue to 50 Hz magnetic fields at levels commonly found near power lines (250-500 microtesla) and measured changes in brain cell communication. They found that direct exposure reduced normal brain signaling, while whole-body exposure increased seizure susceptibility and altered how brain cells strengthen their connections. These findings suggest that everyday electromagnetic fields from electrical infrastructure can measurably alter fundamental brain functions.

Changes in synaptic efficacy and seizure susceptibility in rat brain slices following extremely low-frequency electromagnetic field exposure.

Varró P, Szemerszky R, Bárdos G, Világi I. · 2009

Researchers exposed rat brain tissue to 50 Hz magnetic fields at power line levels. The exposure altered how brain cells communicate and increased seizure-like activity. This suggests electromagnetic fields from power infrastructure may affect brain function, though effects appeared temporary.

Exposure to extremely low frequency magnetic fields induces fos-related antigen-immunoreactivity via activation of dopaminergic D1 receptor.

Shin EJ, Nguyen XK, Nguyen TT, Pham DT, Kim HC. · 2011

Researchers exposed mice to magnetic fields from power lines for one hour daily over two weeks. The exposure caused hyperactivity and altered brain chemistry in areas controlling movement and reward, with changes lasting up to a year, suggesting these fields can permanently affect brain function.

Reactive oxygen species mediates 50-Hz magnetic field-induced EGF receptor clustering via acid sphingomyelinase activation.

Sun L, Chen L, Bai L, Xia Y, Yang X, Jiang W, Sun W. · 2018

Researchers exposed human cells to power line frequency magnetic fields for 15 minutes and found they triggered harmful cellular changes linked to uncontrolled cell growth. The magnetic fields increased damaging molecules called reactive oxygen species, proving these everyday exposures can disrupt normal cell function.

RKIP-Mediated NF-κB Signaling is involved in ELF-MF-mediated improvement in AD rat.

Zuo H, Liu X, Wang D, Li Y, Xu X, Peng R, Song T. · 2018

Chinese researchers exposed Alzheimer's rats to 50 Hz magnetic fields for 60 days and found improved memory and learning abilities. The exposure activated protective brain pathways that reduced inflammation and cognitive decline, suggesting electromagnetic fields might offer therapeutic potential for neurodegenerative diseases.

Mitochondrial ROS release and subsequent Akt Activation potentially mediated the anti-apoptotic effect of a 50-Hz magnetic field on FL cells.

Feng B, Ye C, Qiu L, Chen L, Fu Y, Sun W · 2016

Researchers exposed human cells to a 50-Hz magnetic field (the same frequency as power lines) and found it protected cells from dying when they were later exposed to a toxic chemical. The magnetic field triggered the release of reactive oxygen species from mitochondria (the cell's power plants), which activated protective cellular pathways. This suggests extremely low frequency magnetic fields can influence fundamental cellular survival mechanisms.

NADPH oxidase-produced superoxide mediated a 50-Hz magnetic field-induced epidermal growth factor receptor clustering

Feng B, Dai A, Chen L, Qiu L, Fu Y, Sun W. · 2016

Researchers exposed human cells to 50 Hz magnetic fields (the same frequency used in household electricity) and found that even brief exposures triggered increased production of reactive oxygen species - harmful molecules that can damage cells. The magnetic fields caused specific cellular receptors to cluster together abnormally, a process linked to various health problems including cancer development.

Exposure to a 50-Hz magnetic field induced mitochondrial permeability transition through the ROS/GSK-3β signaling pathway.

Feng B, Qiu L, Ye C, Chen L, Fu Y, Sun W. · 2016

Chinese researchers exposed human cells to magnetic fields at levels similar to those found near power lines and appliances (0.4 mT for 60 minutes). They discovered that this exposure damaged the powerhouses of cells (mitochondria) by triggering a harmful chain reaction involving oxidative stress. The damage occurred through a specific biological pathway that could be blocked with antioxidants, suggesting the effects are real and measurable.

Improvement of spatial memory disorder and hippocampal damage by exposure to electromagnetic fields in an Alzheimer's disease rat model.

Liu X et al. · 2015

Researchers exposed rats with artificially induced Alzheimer's disease symptoms to 50-Hz electromagnetic fields (the same frequency as household power lines) for 60 days. The EMF exposure actually improved the rats' memory and reduced brain damage associated with Alzheimer's disease. This suggests that certain types of electromagnetic field exposure might have protective effects on the brain, contrary to concerns about EMF causing neurological harm.

Extremely low-frequency electromagnetic fields enhance the proliferation and differentiation of neural progenitor cells cultured from ischemic brains.

Cheng Y et al. · 2015

Researchers exposed brain stem cells (neural progenitor cells) from stroke-damaged brains to 50 Hz magnetic fields at 0.4 mT for 7 days. The magnetic field exposure significantly increased both cell multiplication and the development of these stem cells into neurons. This suggests that extremely low frequency electromagnetic fields might help brain recovery after stroke by promoting the growth of new brain cells.

Cellular EffectsNo Effects Found

Effects of 50 Hz magnetic fields on gap junctional intercellular communication in NIH3T3 cells.

Percherancier Y et al. · 2015

Researchers exposed mouse cells to 50 Hz magnetic fields for 24 hours to study whether these fields affect gap junctions (tiny channels that allow cells to communicate with each other). They found no impact on cell communication at the magnetic field strengths tested (0.4 and 1 mT), contradicting some previous studies that suggested power frequency fields could disrupt this cellular function.

Exposure to extremely low-frequency electromagnetic fields modulates Na+ currents in rat cerebellar granule cells through increase of AA/PGE2 and EP receptor-mediated cAMP/PKA pathway.

He YL, Liu DD, Fang YJ, Zhan XQ, Yao JJ, Mei YA. · 2013

Chinese researchers exposed rat brain cells to power line-frequency electromagnetic fields for 10-60 minutes and found sodium channels increased activity by 30-125%. Since sodium channels control nerve signals, this suggests EMF exposure can directly alter how brain cells communicate with each other.

Using model organism Saccharomyces cerevisiae to evaluate the effects of ELF-MF and RF-EMF exposure on global gene expression.

Chen G, Lu D, Chiang H, Leszczynski D, Xu Z · 2012

Researchers exposed yeast cells to both 50 Hz magnetic fields and 1800 MHz radiofrequency radiation to see if electromagnetic fields could change gene activity. They found that magnetic fields caused no confirmed gene changes, while radiofrequency exposure affected only 2-5 genes out of thousands tested. This suggests that EMF effects on basic cellular processes may be more limited than some studies indicate.

Expressions of some antioxidant genes in SH-SY5Y cells treated with β-lapachone, morphine and electromagnetic field.

Mahmoudinasab H, Saadat M. · 2018

Researchers exposed human brain cells (neuroblastoma cells) to 50 Hz electromagnetic fields at 0.5 mT for different time patterns and measured changes in antioxidant gene expression. They found that EMF exposure altered the activity of genes responsible for protecting cells from damage, with different exposure patterns producing different effects. This suggests that even brief EMF exposures can disrupt the cellular machinery that defends against oxidative stress.

DNA & Genetic DamageNo Effects Found

Evaluation of cell viability, DNA single-strand breaks, and nitric oxide production in LPS-stimulated macrophage RAW264 exposed to a 50-Hz magnetic field.

Nakayama M, Nakamura A, Hondou T, Miyata H · 2016

Researchers exposed immune cells called macrophages to 50-Hz magnetic fields (the same frequency as power lines) for 24 hours to see if it would damage their DNA. They found that magnetic field exposure alone caused no harm, but when cells were first activated by bacterial toxins, the magnetic field exposure increased DNA damage and reduced cell survival.

Long-term exposure to ELF-MF ameliorates cognitive deficits and attenuates tau hyperphosphorylation in 3xTg AD mice.

Hu Y et al. · 2016

Researchers exposed mice with Alzheimer's disease to a 50 Hz magnetic field (the type from power lines) for 20 hours daily over 3 months. The magnetic field exposure improved the mice's memory and learning abilities, while also reducing toxic protein buildup in their brains that's characteristic of Alzheimer's. This suggests that certain types of electromagnetic fields might actually have protective effects on brain health rather than harmful ones.

Long-term exposure to ELF-MF ameliorates cognitive deficits and attenuates tau hyperphosphorylation in 3xTg AD mice.

Hu Y et al. · 2016

Researchers exposed genetically modified mice with Alzheimer's disease to extremely low frequency magnetic fields (50Hz, 500μT) for three months daily. The magnetic field exposure improved cognitive function, reduced brain cell death, and decreased tau protein abnormalities that are hallmarks of Alzheimer's disease. This suggests that controlled magnetic field exposure might have therapeutic potential for neurodegenerative conditions.

Effects of short term and long term extremely low frequency magnetic field on depressive disorder in mice: Involvement of nitric oxide pathway.

Ansari AM et al. · 2016

Researchers exposed mice to extremely low frequency magnetic fields (the type emitted by power lines and electrical devices) for either 2 hours once or 2 hours daily for 2 weeks. They found that long-term exposure reduced depression-like behavior in the mice, while short-term exposure interfered with antidepressant medications. This suggests that chronic EMF exposure may alter brain chemistry and affect how psychiatric medications work.