The best understood biological effect of electromagnetic fields is to cause dielectric heating. For example, touching or standing around an antenna while a high-power transmitter is in operation can cause severe burns. These are exactly the kind of burns that would be caused inside a microwave oven.
This heating effect varies with the power and the frequency of the electromagnetic energy. A measure of the heating effect is the specific absorption rate or SAR, which has units of watts per kilogram (W/kg). The IEEE[6] and many national governments have established safety limits for exposure to various frequencies of electromagnetic energy based on SAR, mainly based on ICNIRP Guidelines,[7] which guard against thermal damage.
There are publications which support the existence of complex biological effects of weaker non-thermal electromagnetic fields (see Bioelectromagnetics), including weak ELF magnetic fields[8][9] and modulated RF and microwave fields.[10] Fundamental mechanisms of the interaction between biological material and electromagnetic fields at non-thermal levels are not fully understood.[11]
A 2009 study at the University of Basel in Switzerland found that intermittent (but not continuous) exposure of human cells to a 50 Hz electromagnetic field at a flux density of 1 mT (or 10 G) induced a slight but significant increase of DNA fragmentation in the Comet assay.[12] However that level of exposure is already above current established safety exposure limits
This heating effect varies with the power and the frequency of the electromagnetic energy. A measure of the heating effect is the specific absorption rate or SAR, which has units of watts per kilogram (W/kg). The IEEE[6] and many national governments have established safety limits for exposure to various frequencies of electromagnetic energy based on SAR, mainly based on ICNIRP Guidelines,[7] which guard against thermal damage.
There are publications which support the existence of complex biological effects of weaker non-thermal electromagnetic fields (see Bioelectromagnetics), including weak ELF magnetic fields[8][9] and modulated RF and microwave fields.[10] Fundamental mechanisms of the interaction between biological material and electromagnetic fields at non-thermal levels are not fully understood.[11]
A 2009 study at the University of Basel in Switzerland found that intermittent (but not continuous) exposure of human cells to a 50 Hz electromagnetic field at a flux density of 1 mT (or 10 G) induced a slight but significant increase of DNA fragmentation in the Comet assay.[12] However that level of exposure is already above current established safety exposure limits
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