fraggy
3 Answers
Ed1530
American Journal of Epidemiology
Copyright © 2001 by the Johns Hopkins University Bloomberg School of Public Health
All rights reserved
Vol. 154, No. 7
Printed in U.S.A.
The effects of chronic exposure to environmental electric
and magnetic fields (EMF) have been the subject of intensive
research leading to no definitive answers
| 12 years ago. Rating: 3 | |
Grit Savage
lindilou
Biological hazards
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[3] and many national governments have established safety limits for exposure to various frequencies of electromagnetic energy based on SAR, mainly based on ICNIRP Guidelines,[4] 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[5][6] and modulated RF and microwave fields.[7] Fundamental mechanisms of the interaction between biological material and electromagnetic fields at non-thermal levels are not fully understood.[8]
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.[9] However that level of exposure is already above current established safety exposure limits.
http://en.wikipedia.org/wiki/Electromagnetic_radiation_and_health
| 12 years ago. Rating: 2 | |
