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.
Based on Building Biology Institute guidelines (mG (milligauss)):
See where common exposures fall on the scale:
Showing 486 studies with measured magnetic fields (elf) exposure
Cui Y, Ge Z, Rizak JD, Zhai C, Zhou Z, Gong S, Che Y. · 2012
Researchers exposed mice to magnetic fields from power lines and appliances, then tested their learning abilities. The exposed mice showed significant learning problems and brain cell damage in memory regions, suggesting everyday electromagnetic fields may harm brain function.
Patruno A et al. · 2012
Researchers exposed THP-1 cells to a 50 Hz, 1 mT electromagnetic field for 24 hours, with or without LPS, to study effects on matrix metalloproteinases (MMPs) and their inhibitor TIMP-1. Exposure was associated with a reduction of antioxidant enzyme activity and an enhancement of nitrogen intermediates involving the iNOS pathway. The researchers analyzed the role of nitration of TIMP-1 in increasing the activity of MMPs in EMF-exposed cells, and molecular modeling identified at least two protein sites, Y120 and Y38 and/or Y72, as plausible targets. The results may suggest a pathway connecting an imbalance of MMPs and their cognate inhibitor TIMP-1.
Bułdak RJ et al. · 2012
Researchers assessed how cisplatin and an extremely low frequency electromagnetic field (ELF-EMF) affected antioxidant enzyme activity, lipid peroxidation, DNA damage, and reactive oxygen species (ROS) production in AT478 carcinoma cells. Cells were cultured with cisplatin for 24 and 72 hours and irradiated with 50 Hz/1 mT ELF-EMF for 16 minutes using a solenoid. When ELF-EMF was combined with cisplatin, ROS levels, antioxidant enzyme activity, and DNA damage all decreased compared to cisplatin alone, but ELF-EMF by itself increased DNA damage relative to control cells.
Calabrò E, Condello S, Magazù S, Ientile, R. · 2011
Masuda H et al. · 2011
Researchers exposed rat brain membrane fractions and human 5-HT1B receptors in C6-glial cells to 50-Hz magnetic field at 1 mT. No significant difference was found in the affinity constant of serotonin for the 5-HT1B receptor between exposed and sham-exposed rat membranes. The same lack of affinity change was confirmed using a chemical agonist and in human 5-HT1B receptors in C6-glial cells. Forskolin-stimulated cAMP production inhibited by serotonin was also not modified by exposure in C6-glial cells.
Patruno A et al. · 2011
The study estimated kinetic constants of catalase, cytochrome P450, and inducible nitric oxide synthase in human HaCaT and THP-1 cell lines exposed to ELF-EMF. To evaluate cellular responses to an inflammatory stimulus, both cell lines were treated with lipopolysaccharide. The effects of ELF-EMF depend upon frequency, amplitude, and length of exposure, and are also related to intrinsic susceptibility and responsiveness of different cell types.
Akan Z, Aksu B, Tulunay A, Bilsel S, Inhan-Garip A · 2010
Researchers applied 50 Hz, 1 mT electromagnetic fields for 4 to 6 hours to human monocytic leukemia cells (THP-1) that had been stimulated with Staphylococcus aureus or interferon gamma/lipopolysaccharide. Field application increased nitric oxide levels, with the increase appearing earlier and being more prominent in cells stimulated with S. aureus. ELF-EMF alone caused increased hsp70 levels in a time-dependent manner, and the growth curve of exposed bacteria was lower than the control. The researchers suggested that ELF-EMF could be exploited for beneficial uses.
Garip AI, Akan Z. · 2010
Researchers investigated the effect of ELF-EMF on apoptosis in K562 human leukemia cells, with and without oxidative stress, and examined links to heat-shock protein 70 levels. ELF-EMF at 1 mT and 50 Hz was applied for 3 hours, with one group of cells treated with H2O2 to induce oxidative stress and another left untreated. In cells not exposed to oxidative stress, ELF-EMF caused a decrease in the number of apoptotic cells and a slight increase in viability. In cells treated with H2O2, ELF-EMF increased the number of apoptotic cells, and hsp70 and reactive oxygen species levels were also increased.
Frahm J, Mattsson MO, Simkó M. · 2010
Researchers exposed mouse macrophages to a 50 Hz, 1.0 mT magnetic field and measured changes in reactive oxygen species production and protein expression. Short-term exposures of two hours or less caused slight and transient decreases in several proteins, including clathrin, adaptin, PI3-kinase, protein kinase B, and PP2A, while longer exposures had no effect on these proteins. The stress proteins Hsp70 and Hsp110 showed increased levels at certain time points but not generally.
Cuccurazzu B et al. · 2010
Italian researchers exposed mice to 50 Hz electromagnetic fields (European power line frequency) for up to seven hours daily over one week. This significantly increased new brain cell growth in the hippocampus, improving long-term memory formation and suggesting potential therapeutic applications for brain regenerative medicine.
Cuccurazzu B et al. · 2010
The exposure significantly enhanced neurogenesis in the dentate gyrus, with increased numbers of cells labeled for markers of new and developing neurons. Roughly half of the newly generated neurons survived 30 days after stimulation and became mature neurons integrated into the granule cell layer. The new mature neurons were associated with increased long-term potentiation, indicating an influence on hippocampal synaptic plasticity.
Canseven AG, Coskun S, Seyhan N · 2008
Researchers exposed guinea pigs to 50 Hz magnetic fields at 1, 2, and 3 mT for 4 h/day and 8 h/day for 5 days, measuring malondialdehyde, nitric oxide, glutathione, and myeloperoxidase activity in heart and liver tissues. MDA levels increased in the liver in some groups but decreased in both liver and heart in group VII. The researchers concluded that field intensity and exposure duration are among the conditions that influence free radical formation and antioxidant enzyme behavior.
Piacentini R, Ripoli C, Mezzogori D, Azzena GB, Grassi C. · 2008
Erdal N, Gürgül S, Tamer L, Ayaz L · 2008
Researchers exposed adult Wistar-Albino rats to an extremely low frequency magnetic field (50 Hz, 1 mT, 4 hours per day) to study oxidative and nitrosative stress in liver tissue. 3-nitrotyrosine (3-NT) levels were significantly increased in exposed female rats compared to female controls, but no significant difference was found between exposed and control male rats. Malondialdehyde (MDA) levels showed no significant differences between control and exposed rats in either sex.
Partsvania B, Sulaberidze T, Modebadze Z, Shoshiashvili L. · 2008
Researchers studied how extremely low-frequency magnetic fields at 8.34 and 217 Hz affected the ability of single neurons in the mollusk Helix Pomatia to habituate to repeated stimuli. Brain ganglia were exposed to magnetic fields with peak values between 1 and 6 mT using Helmholtz coils, and neuron activity was recorded with a standard microelectrode technique. Exposure caused dehabituation, which the researchers described as occurring through degradation of the signal to noise ratio and alteration of the neuron's normal function.
Che Y, Sun H, Cui Y, Zhou D, Ma Y. · 2007
Researchers examined the effects of a 50 Hz magnetic field at 1 mT intensity on learning and memory in Lohmann brown domestic chicks using a detour learning task. Chicks exposed for 20 hours per day showed a significant impairment in detour learning, while those exposed for 50 minutes per day showed no effect.
Che Y, Sun H, Cui Y, Zhou D, Ma Y. · 2007
Researchers exposed young chicks to magnetic fields from power lines for 20 hours daily and tested their learning ability. Chicks with prolonged exposure showed significantly impaired learning and memory compared to unexposed chicks, suggesting extended magnetic field exposure may interfere with brain development.
Frahm J, Lantow M, Lupke M, Weiss DG, Simkó M · 2006
Researchers investigated whether extremely low frequency electromagnetic fields affect cellular functions and immunologic parameters of mouse macrophages. Magnetic field exposure led to a 1.6-fold increased uptake of latex beads in exposed cells compared to controls after 45 minutes. IL-1β formation increased significantly after 4 hours and reached a maximum 12.3-fold increase after 24 hours compared to controls. All tested flux densities significantly stimulated free radical formation, and no significant differences in micronucleus formation were found in exposed cells.
Aksen F, Akdag MZ, Ketani A, Yokus B, Kaya A, Dasdag S. · 2006
Reale M et al. · 2006
Researchers investigated whether overnight exposure to a 1 mT, 50-Hz sinusoidal electromagnetic field affects the expression of iNOS and MCP-1 in human monocytes. EMF exposure affected iNOS and MCP-1 expression in cultured human mononuclear cells at both the mRNA level and the protein level. iNOS was down-regulated while MCP-1 was up-regulated.
Lupke M, Rollwitz J, Simkó M. · 2004
Researchers investigated how 50 Hz extremely low frequency magnetic fields activate human cells to release reactive oxygen intermediates. They examined free radical production in human umbilical cord blood-derived monocytes and in human Mono Mac 6 cells. Exposure to 1 mT ELF-MF for 45 minutes produced a significant increase in superoxide radical anion production of up to 1.4 fold and an increase in ROS release of up to 1.2 fold in monocytes. Mono Mac 6 cells showed superoxide radical anion and ROS production of up to 1.4 and 1.5 fold, respectively, leading the researchers to suggest these cells are more sensitive to ELF-MF than monocytes.
Rollwitz J, Lupke M, Simkó M · 2004
Researchers studied the effects of 50 Hz magnetic fields on free radical production in mouse bone marrow-derived macrophages and monocytes. Exposure to the magnetic fields at a flux density of 1 mT produced a significant increase in free radical production in both cell types. The radicals produced were mainly superoxide anion radicals, found in macrophages at 33% and in their precursor cells at 24%.
André-Jean Berteaud et al. · 1971
This 1971 French study investigated whether pulsed and modulated UHF electromagnetic radiation could influence the development of Trypanosoma equiperdum infections in laboratory animals. The research examined the relationship between EMF exposure and parasitemia (parasite levels in blood), representing early work connecting electromagnetic fields to biological infection processes.
Espinosa JM, Liberti M, Lagroye I, Veyret B. · 2006
Researchers studied the binding properties of the serotonin 5-HT1B receptor in rat brain membranes under exposure to AC and DC magnetic fields. One-hour exposures at 1.1 mT at 50 Hz caused statistically significant increases in both the K(D) and B(max) binding parameters, from 1.74 to 4.51 nM and from 1428 to 2137 CPM, respectively. DC fields had a lesser effect compared to AC fields at low values of K(Dsham), but decreased the affinity at higher values of K(Dsham). The researchers described these findings as one of the few documented pieces of evidence for cell-free effects of DC and extremely low frequency AC magnetic fields in the mT range.
Lee BC et al. · 2004
Researchers investigated whether a 60 Hz magnetic field could affect the antioxidant defense system in mouse brain by measuring chemiluminescence and superoxide dismutase (SOD) activity in brain homogenates. A chemiluminescence measure linked to oxidative stress was significantly increased in mice exposed to 60 Hz, 12 G for 3 hours compared to the sham-exposed control group. Brain SOD activity was also significantly increased in the exposed group. The researchers suggest these results indicate the field could deteriorate the antioxidant defensive system through reactive oxygen species other than superoxide radicals.