8,655 Studies Reviewed. 86.9% 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 487 studies with measured magnetic fields (elf) exposure

Response of Hippocampal Neurons and Glial Cells to Alternating Magnetic Field in Gerbils Submitted to Global Cerebral Ischemia.

Rauš S et al. · 2013

Researchers exposed gerbils to 50 Hz magnetic fields (the same frequency as power lines) after inducing stroke-like brain damage to see if EMF exposure affected recovery. They found that animals exposed to magnetic fields at 0.5 mT had significantly less brain cell death and better immune cell responses compared to unexposed animals. This suggests that certain magnetic field exposures might actually protect brain tissue during injury recovery.

Assessment of genotoxic and cytotoxic hazards in brain and bone marrow cells of newborn rats exposed to extremely low-frequency magnetic field.

Rageh MM, El-Gebaly RH, El-Bialy NS. · 2012

Researchers exposed newborn rats to magnetic fields at 0.5 milliTesla (similar to levels near some power lines) for 30 days and found significant DNA damage in brain cells and bone marrow. The study also detected a four-fold increase in cellular abnormalities and signs of oxidative stress (cellular damage from harmful molecules). This suggests that developing organisms may be particularly vulnerable to magnetic field exposure during critical growth periods.

Extremely low frequency magnetic field induced changes in motor behaviour of gerbils submitted to global cerebral ischemia.

Rauš S, Selaković V, Radenović L, Prolić Z, Janać B. · 2012

Serbian researchers exposed gerbils with induced stroke-like brain damage to 50 Hz magnetic fields (the same frequency as power lines) for seven days. The magnetic field exposure significantly reduced the hyperactive behavior that typically follows brain injury from lack of blood flow. This suggests that extremely low frequency magnetic fields may influence brain recovery processes after stroke or similar injuries.

Stress-related endocrinological and psychopathological effects of short- and long-term 50 Hz electromagnetic field exposure in rats

Szemerszky R, Zelena D, Barna I, Bárdos G. · 2010

Researchers exposed rats to 50 Hz magnetic fields (the type from power lines) for either 5 days or 4-6 weeks to study stress effects. They found that long-term exposure led to depression-like behavior, elevated stress hormones, and higher blood glucose levels, while short-term exposure showed no effects. This suggests that chronic exposure to magnetic fields may act as a mild stressor that could contribute to depression and metabolic problems.

Stress-related endocrinological and psychopathological effects of short- and long-term 50Hz electromagnetic field exposure in rats.

Szemerszky R, Zelena D, Barna I, Bárdos G. · 2010

Researchers exposed rats to 50 Hz electromagnetic fields (household electrical frequency) for weeks and found increased blood sugar, stress hormones, and depression-like behavior compared to short-term exposure. This suggests chronic EMF exposure may act as a mild stressor affecting mood and metabolism.

Effect of short-term 50 Hz electromagnetic field exposure on the behavior of rats.

Balassa T, Szemerszky R, Bárdos G. · 2009

Researchers exposed rats to 50 Hz magnetic fields at 500 microtesla (the workplace safety limit) for 20 minutes and found the animals became more passive and anxious in behavioral tests. The magnetic field exposure increased situational anxiety and reduced activity levels, though it didn't affect social behaviors. This suggests that even brief exposure to magnetic fields at legally permitted levels can alter brain function and behavior.

Effect of continuous exposure to alternating magnetic field (50 Hz, 0.5 mT) on serotonin and dopamine receptors activity in rat brain.

Janać B, Tovilović G, Tomić M, Prolić Z, Radenović L. · 2009

Researchers exposed rats to extremely low frequency magnetic fields (the same type produced by power lines and household appliances) for up to 7 days and measured changes in brain chemistry. They found that these magnetic fields altered serotonin receptors in the brain's prefrontal cortex, with effects becoming more pronounced after longer exposure periods. This matters because serotonin plays a crucial role in mood, sleep, and behavior regulation.

Effect of continuous exposure to alternating magnetic field (50 Hz, 0.5 mT) on serotonin and dopamine receptors activity in rat brain.

Janać B, Tovilović G, Tomić M, Prolić Z, Radenović L. · 2009

Serbian researchers exposed rats to power line frequency magnetic fields (50 Hz) for up to seven days. The exposure significantly altered serotonin brain receptors that control mood and behavior, with effects becoming stronger over longer exposure periods. This suggests household electrical fields may impact brain chemistry.

Stimulation of phagocytosis and free radical production in murine macrophages by 50 Hz electromagnetic fields.

Simkó M, Droste S, Kriehuber R, Weiss DG · 2001

Researchers exposed immune cells called macrophages from mouse bone marrow to 50 Hz magnetic fields (the same frequency as power lines) for 45 minutes. They found that these fields significantly increased the cells' ability to engulf foreign particles by 36% and boosted production of free radicals. This suggests that even short exposures to power frequency magnetic fields can activate immune system responses at the cellular level.

Melatonin and N-tert-butyl-alpha-phenylnitrone block 60-Hz magnetic field-induced DNA single and double strand breaks in rat brain cells.

Lai H, Singh NP · 1997

Researchers exposed rats to 60-Hz magnetic fields (the same frequency as household electricity) and found that this exposure caused DNA breaks in brain cells. However, when the rats were given melatonin or another antioxidant compound before exposure, these protective substances completely blocked the DNA damage. This suggests that magnetic fields may damage DNA through free radical formation, and that antioxidants might offer protection.

Increased vascular permeability in the circumventricular organs of adult rat brain due to stimulation by extremely low frequency magnetic fields

Gutiérrez-Mercado YK et al. · 2013

Researchers exposed rats to extremely low frequency magnetic fields (120 Hz at 0.66 mT) and found that these fields increased blood vessel permeability in specific brain regions called circumventricular organs. The magnetic field exposure caused blood vessels to dilate and become more permeable to substances that normally can't cross into brain tissue. This suggests that ELF magnetic fields can compromise the brain's protective blood barrier system.

Protective properties of Myrtus communis extract against oxidative effects of extremely low-frequency magnetic fields on rat plasma and hemoglobin.

Seif F, Bayatiani MR, Ansarihadipour H, Habibi G, Sadelaji S · 2018

Researchers exposed rats to magnetic fields from power lines for 2 hours daily over a month, finding significant blood damage and reduced antioxidant defenses. Myrtle plant extract prevented these harmful effects, suggesting magnetic field exposure causes oxidative stress but natural compounds may offer protection.

Comparative of transcranial magnetic stimulation and other treatments in experimental autoimmune encephalomyelitis

Medina-Fernandez FJ et al. · 2018

Researchers tested whether transcranial magnetic stimulation (TMS) using 60 Hz magnetic fields at 0.7 mT could help treat an animal model of multiple sclerosis. They found that TMS reduced brain inflammation and oxidative stress (cellular damage from unstable molecules) more effectively than standard pharmaceutical treatments. This suggests magnetic field therapy might have protective effects on the nervous system.

Effects of transcranial magnetic stimulation on oxidative stress in experimental autoimmune encephalomyelitis.

Medina-Fernandez FJ et al. · 2017

Researchers used magnetic field therapy (similar to medical TMS treatment) on rats with an artificially induced multiple sclerosis-like condition. The 60 Hz magnetic fields at 0.7 milliTesla significantly reduced brain damage, improved motor symptoms, and decreased harmful oxidative stress. This suggests that controlled magnetic field exposure might have therapeutic potential for neurological conditions involving brain inflammation.

Effects of transcranial magnetic stimulation on oxidative stress in experimental autoimmune encephalomyelitis.

Medina-Fernandez FJ et al. · 2017

Researchers exposed rats with multiple sclerosis-like symptoms to magnetic field stimulation (0.7 mT at 60 Hz) for 2 hours daily over 3 weeks. The magnetic field treatment significantly reduced brain and spinal cord damage, improved motor symptoms, and decreased harmful oxidative stress while boosting protective antioxidant systems. This suggests that certain types of electromagnetic field exposure may actually have therapeutic benefits for neurological conditions.

Exposure to 50 Hz electromagnetic field changes the efficiency of the scorpion alpha toxin.

Jankowska M et al. · 2015

Polish researchers exposed cockroaches to 50 Hz electromagnetic fields (the same frequency used in electrical power systems) and found it changed how their nervous systems responded to scorpion toxin. The EMF exposure altered nerve activity patterns and reduced the toxin's effectiveness, demonstrating that power frequency fields can modify how the nervous system functions at the cellular level.

Neuroprotective effects of extremely low-frequency electromagnetic fields on a Huntington's disease rat model: effects on neurotrophic factors and neuronal density

Tasset I et al. · 2012

Researchers exposed rats with Huntington's disease-like symptoms to extremely low-frequency electromagnetic fields (60 Hz at 0.7 milliTesla) for 21 days. The EMF exposure improved the rats' neurological function, increased protective brain proteins, and prevented nerve cell death in the brain region most affected by Huntington's disease. This suggests that specific types of EMF exposure might have therapeutic potential for neurodegenerative diseases.

Neuroprotective effects of extremely low-frequency electromagnetic fields on a Huntington's disease rat model: effects on neurotrophic factors and neuronal density.

Tasset I et al. · 2012

Researchers exposed rats with a Huntington's disease-like condition to 60 Hz electromagnetic fields at 0.7 milliTesla (similar to standing very close to power lines) for 4 hours daily over 21 days. The electromagnetic field exposure significantly protected brain cells from damage, reduced harmful oxidative stress, and preserved neurons that would otherwise die from the disease. This suggests that certain types of electromagnetic fields might have therapeutic potential for neurodegenerative diseases.

Sinusoidal ELF magnetic fields affect acetylcholinesterase activity in cerebellum synaptosomal membranes

Ravera S et al. · 2010

Italian researchers exposed brain cell membranes to 50 Hz magnetic fields (the same frequency as electrical power lines) and found that a key enzyme called acetylcholinesterase was reduced by 27%. This enzyme is crucial for proper nerve signaling in the brain. The effect occurred at magnetic field levels of 0.74 milliTesla and was completely reversible when the exposure stopped.