Electromagnetic radiation and health
Electromagnetic radiation can be classified into two types: ionizing radiation and non-ionizing radiation, based on its capability of ionizing atoms and breaking chemical bonds. Ultraviolet and higher frequencies, such as X-rays or gamma rays are ionizing, and these pose their own special hazards: see radiation and radiation poisoning. Non-ionizing radiation, discussed here, is associated with electrical and biological hazards.
Types of hazards 
Electrical hazards 
Strong radiation can induce current capable of delivering an electric shock to persons or animals. It can also overload and destroy electrical equipment. The induction of currents by oscillating magnetic fields is also the way in which solar storms disrupt the operation of electrical and electronic systems, causing damage to and even the explosion of power distribution transformers, blackouts (as occurred in 1989), and interference with electromagnetic signals (e.g. radio, TV, and telephone signals).
Fire hazards 
Extremely high power electromagnetic radiation can cause electric currents strong enough to create sparks (electrical arcs) when an induced voltage exceeds the breakdown voltage of the surrounding medium (e.g. air). These sparks can then ignite flammable materials or gases, possibly leading to an explosion.
This can be a particular hazard in the vicinity of explosives or pyrotechnics, since an electrical overload might ignite them. This risk is commonly referred to as HERO (Hazards of Electromagnetic Radiation to Ordnance). MIL-STD-464A mandates assessment of HERO in a system, but Navy document OD 30393 provides design principles and practices for controlling electromagnetic hazards to ordnance.
On the other hand, the risk related to fueling is known as HERF (Hazards of Electromagnetic Radiation to Fuel). NAVSEA OP 3565 Vol. 1 could be used to evaluate HERF, which states a maximum power density of 0.09 W/m² for frequencies under 225 MHz (i.e. 4.2 meters for a 40 W emitter).
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 and many national governments have established safety limits for exposure to various frequencies of electromagnetic energy based on SAR, mainly based on ICNIRP Guidelines, 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 and modulated RF and microwave fields. Fundamental mechanisms of the interaction between biological material and electromagnetic fields at non-thermal levels are not fully understood.
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. However that level of exposure is already above current established safety exposure limits.
Positions of governments and scientific bodies 
World Health Organization 
In May 2011, the WHO's International Agency for Research on Cancer published a review of the evidence on health risks of electromagnetic fields (EMFs), and concluded that there was limited evidence that cellphone users might be at increased risk of glioma and acoustic neuroma, and that there was inadequate evidence of any other health risks posed by EMF. This "possibly carcinogenic" classification was often misinterpreted, meaning only "that there is very little scientific evidence as to the carcinogenicity of cell phone use".
Health Canada 
"There is no conclusive evidence of any harm caused by exposures [to electric and magnetic fields] at levels found in Canadian homes and schools, including those located just outside the boundaries of power line corridors."
U.S. military definition 
- Electromagnetic radiation hazards (RADHAZ or EMR hazards): Hazards caused by a transmitter/antenna installation that generates electromagnetic radiation in the vicinity of ordnance, personnel, or fueling operations in excess of established safe levels or increases the existing levels to a hazardous level; or a personnel, fueling, or ordnance installation located in an area that is illuminated by electromagnetic radiation at a level that is hazardous to the planned operations or occupancy. These hazards will exist when an electromagnetic field of sufficient intensity is generated to: (a) induce or otherwise couple currents or voltages large enough to initiate electroexplosive devices or other sensitive explosive components of weapon systems, ordnance, or explosive devices; (b) cause harmful or injurious effects to humans and wildlife; (c) create sparks having sufficient magnitude to ignite flammable mixtures of materials that must be handled in the affected area. —Department of Defense Dictionary of Military and Associated Terms
Electric power transmission 
The preponderance of evidence suggests that the low-power, low-frequency, electromagnetic radiation associated with household current does not constitute a short or long term health hazard, and although some biophysical mechanisms for the promotion of cancer have been proposed (such as the electric fields around power lines attracting aerosol pollutants), none have been substantiated.  Nevertheless, some research has reported correlation with a number of adverse health effects, although controversy can include whether observed correlation implies causation. These include, but are not limited to, childhood leukemia, adult leukemia, neurodegenerative diseases (such as amyotrophic lateral sclerosis), miscarriage, and Alzheimer's disease. Some research has found no relationship with amyotrophic lateral sclerosis, Parkinson's disease, or multiple sclerosis.
One response to the potential dangers of overhead power lines is to place them underground. The earth and enclosures surrounding underground cables prevent the electric field from radiating significantly beyond the power lines, and greatly reduce the magnetic field strength radiating from the power lines, into the surrounding area. However, the cost of burying and maintaining cables at transmission voltages is several times greater than overhead power lines.
Leukemia and cancer 
In 1997 the National Cancer Institute (NCI) released a report published in the New England Journal of Medicine, the result of a seven-year epidemiological investigation. The study investigated 638 children with acute lymphoblastic leukemia (ALL) and 620 controls and concluded that their study provided "little evidence that living in homes characterized by high measured time-weighted average magnetic-field levels or by the highest wire-code category increases the risk of ALL in children." Following the report, the US Department of Energy disbanded the EMF Research and Public Information Dissemination (RAPID) Program, saying that its services were no longer needed.
In 2005, the Canadian Federal-Provincial-Territorial Radiation Protection Committee said, "The outcome of a recently conducted pooled analysis of several epidemiological studies shows a two-fold increase in the risk of leukemia in children living in homes, where the average magnetic field levels are greater than 0.4 microtesla (4 milligauss). [However,] it is the opinion of [this committee] that the epidemiological evidence to date is not strong enough to justify a conclusion that EMFs in Canadian homes, regardless of locations from power lines, cause leukemia in children."
The World Health Organization issued a fact sheet, No. 322, in June, 2007 based on the findings of a WHO work group (2007), the IARC (2002) and the ICNIRP (2003), which reviewed research conducted since the earlier publication. The fact sheet says "that there are no substantive health issues related to ELF electric fields at levels generally encountered by members of the public." For ELF magnetic fields, the fact sheet says, "the evidence related to childhood leukaemia is not strong enough to be considered causal", and "[as regards] other childhood cancers, cancers in adults, ... The WHO Task Group concluded that scientific evidence supporting an association between ELF magnetic field exposure and all of these health effects is much weaker than for childhood leukaemia. In some instances (i.e., for ... breast cancer) the evidence suggests that these fields do not cause them."
According to Dr. Lakshmikumar at the National Physical Laboratory, India, a direct, causal, link between RF radiation and cancer (including leukemia) would require one to be "willing to discard Planck's Law… and the entire body of quantum physics." 
In 2010, Maslanyj et al., applying the Bradford-Hill criteria to available evidence, considered the application of low-cost exposure reduction measures as appropriate precautionary responses to "small and uncertain public health risks". Even after pooling all the data, they found it fell short of establishing "strength of association, dose-response relationship, biological plausibility and coherence, and analogy". They recognised that controversy would continue so long as other interpretations of the data were possible.
In 2001, Ahlbom et al. conducted a review into EMFs and Health, and found that there was a doubling in childhood leukemia for magnetic fields of over 0.4 µT, but said that it "... may be partly due to bias. This is difficult to interpret in the absence of a known mechanism or reproducible experimental support."
In 2002 a study by Michelozzi et al. found a relationship between leukemia and proximity to the Vatican Radio station transmitters although "the study has limitations because of the small number of cases and the lack of exposure data."
In 2005 Draper et al. found a 70% increase in childhood leukemia for those living within 200 metres (656 ft) of an overhead transmission line, and a 23% increase for those living between 200 and 600 metres (656 and 1,969 ft). The authors concluded that "the relation may be due to chance or confounding." The authors considered it unlikely that the increase from 200 m to 600 m is related to magnetic fields as they are well below 0.4 µT at this distance. Bristol University (UK) has published work on a theory that could account for this increase, and would also provide a potential mechanism, being that the electric fields around power lines attract aerosol pollutants.
Other findings 
The World Health Organisation issued Factsheet No. 263 in October 2001 on ELF (Extremely low frequency) EMFs and cancer. It said that they were "possibly carcinogenic", based primarily on IARC's similar evaluation with respect to childhood leukemia. It also said that there was "insufficient" data to draw any conclusions on other cancers. The WHO later noted that result had been based on evidence which was "weakened by methodological problems" and that "on balance, the evidence related to childhood leukaemia is not strong enough to be considered causal."
UK SAGE report 
The UK Department of Health set up the Stakeholder Advisory Group on ELF EMFs (SAGE) to explore the implications and to make recommendations for a precautionary approach to power frequency electric and magnetic fields in light of any evidence of a link between EMF and childhood leukemia. The first interim assessment of this group was released in April 2007 , and found that the link between proximity to power lines and childhood leukemia was sufficient to warrant a precautionary recommendation, including an option to lay new power lines underground where possible and to prevent the building of new residential buildings within 60 m (197 ft) of existing power lines. The latter of these options was not an official recommendation to government as the cost-benefit analysis based on the increased risk for childhood leukemia alone was considered insufficient to warrant it. The option was considered necessary for inclusion as, if found to be real, the weaker association with other health effects would make it worth implementing.
Mobile telephones 
Mobile phone radiation and health concerns have been raised, especially following the enormous increase in the use of wireless mobile telephony throughout the world (as of August 2005[update], there were more than 2 billion users worldwide). Mobile phones use electromagnetic radiation in the microwave range, and some[unreliable medical source?] believe this may be harmful to human health. These concerns have induced a large body of research (both epidemiological and experimental, in non-human animals as well as in humans). Concerns about effects on health have also been raised regarding other digital wireless systems, such as data communication networks.
The World Health Organization, based upon the consensus view of the scientific and medical communities, states that health effects (e.g. headaches or promotion of cancer) are unlikely to be caused by cellular phones or their base stations, and expects to make recommendations about mobile phones in the third quarter of 2010 at the earliest, or the first quarter of 2011 at the latest[dated info].
See also 
- Background radiation
- BioInitiative Report
- COSMOS cohort study
- Electrical sensitivity
- EMF measurements
- Microwave News
- Microwave auditory effect
- Mobile phone radiation and health
- Specific absorption rate
- Wireless electronic devices and health
- Transcript of "Blackout: The Sun-Earth Connection", Part 4: When Solar Plasma Distorts Earth's Magnetic Field
- "Standard for Safety Level with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3KHz to 300GHz". IEEE Std (IEEE). C95.1. Oct 2005.
- International Commission on Non-Ionizing Radiation Protection (April 1998). "Guidelines for limiting exposure to time-varying electric, magnetic, and electromagnetic fields (up to 300 GHz)". Health Physics 74 (4): 494–522. PMID 9525427.
- Delgado JM, Leal J, Monteagudo JL, Gracia MG (May 1982). "Embryological changes induced by weak, extremely low frequency electromagnetic fields". Journal of Anatomy 134 (3): 533–51. PMC 1167891. PMID 7107514.
- Harland JD, Liburdy RP (1997). "Environmental magnetic fields inhibit the antiproliferative action of tamoxifen and melatonin in a human breast cancer cell line". Bioelectromagnetics 18 (8): 555–62. doi:10.1002/(SICI)1521-186X(1997)18:8<555::AID-BEM4>3.0.CO;2-1. PMID 9383244.
- Aalto S, Haarala C, Brück A, Sipilä H, Hämäläinen H, Rinne JO (July 2006). "Mobile phone affects cerebral blood flow in humans". Journal of Cerebral Blood Flow and Metabolism 26 (7): 885–90. doi:10.1038/sj.jcbfm.9600279. PMID 16495939.
- Binhi, Vladimir N; Repiev, A & Edelev, M (translators from Russian) (2002). Magnetobiology: underlying physical problems. San Diego: Academic Press. pp. 1–16. ISBN 978-0-12-100071-4. OCLC 49700531.
- Focke F, Schuermann D, Kuster N, Schär P (November 2009). "DNA fragmentation in human fibroblasts under extremely low frequency electromagnetic field exposure". Mutation Research 683 (1–2): 74–83. doi:10.1016/j.mrfmmm.2009.10.012. PMID 19896957.
- "IARC classifies radiofrequency electromagnetic fields as possibly carcinogenic to humans" (Press release). 2011-05-31. Retrieved 2011-08-01.
- Baan R, Grosse Y, Lauby-Secretan B, El Ghissassi F, Bouvard V, Benbrahim-Tallaa L, Guha N, Islami F, Galichet L, Straif K, on behalf of the WHO International Agency for Research on Cancer Monograph Working Group (1 July 2011). "Carcinogenicity of radiofrequency electromagnetic fields". The Lancet Oncology 12 (7): 624–6. doi:10.1016/S1470-2045(11)70147-4. PMID 21845765. (free, registration required)
- Boice JD Jr, Tarone RE (2011). "Cell phones, cancer, and children". J Natl Cancer Inst 103 (16): 1211–3. doi:10.1093/jnci/djr285. PMID 21795667.
- "Electric and Magnetic Fields at Extremely Low Frequencies". Health Canada. 2010-01-19. Retrieved 2010-05-24.
- Fews AP, Henshaw DL, Keitch PA, Close JJ, Wilding RJ (December 1999). "Increased exposure to pollutant aerosols under high voltage power lines". International Journal of Radiation Biology 75 (12): 1505–21. doi:10.1080/095530099139115. PMID 10622257. (primary source)
- Fews AP, Henshaw DL, Wilding RJ, Keitch PA (December 1999). "Corona ions from power lines and increased exposure to pollutant aerosols". International Journal of Radiation Biology 75 (12): 1523–31. doi:10.1080/095530099139124. PMID 10622258. (primary source)
- "Electromagnetic fields and public health: Exposure to extremely low frequency fields". Fact sheet No. 322. World Health Organization. June 2007. Retrieved January 23, 2008.
- "Electromagnetic fields and public health: Electromagnetic hypersensitivity". Fact sheet No.296. World Health Organization. December 2005. Retrieved November 17, 2007.
- "Electric and Magnetic Fields and Public Health". National Policy. American Physical Society. April 15, 2005. Retrieved January 29, 2008.
- "Electric and Magnetic Fields Associated with the Use of Power" (PDF). National Institute of Environmental Health Sciences. 2002-06. Retrieved January 29, 2008.
- International Commission on Non-Ionizing Radiation Protection (August 2004). "ICNIRP statement related to the use of security and similar devices utilizing electromagnetic fields". Health Physics 87 (2): 187–96. doi:10.1097/00004032-200408000-00007. PMID 15257219. "Similarly, there is no convincing evidence for an association with neurologic disease, birth defects, heart disease, or suicide."
- "Report 7 of the Council on Scientific Affairs (I-94)". American Medical Association. December 1994. Retrieved December 3, 2009. "no scientifically documented health risk has been associated with the usually occurring levels of electromagnetic fields"
- Tynes T, Klaeboe L, Haldorsen T (May 2003). "Residential and occupational exposure to 50 Hz magnetic fields and malignant melanoma: a population based study". Occupational and Environmental Medicine 60 (5): 343–7. doi:10.1136/oem.60.5.343. PMC 1740536. PMID 12709519. (primary source)
- Feychting M, Jonsson F, Pedersen NL, Ahlbom A (July 2003). "Occupational magnetic field exposure and neurodegenerative disease". Epidemiology 14 (4): 413–9; discussion 427–8. doi:10.1097/01.EDE.0000071409.23291.7b. PMID 12843764.
- Håkansson N, Gustavsson P, Johansen C, Floderus B (July 2003). "Neurodegenerative diseases in welders and other workers exposed to high levels of magnetic fields". Epidemiology 14 (4): 420–6; discussion 427–8. doi:10.1097/01.EDE.0000078446.76859.c9. PMID 12843765. (primary source)
- Ahlbom A (2001). "Neurodegenerative diseases, suicide and depressive symptoms in relation to EMF". Bioelectromagnetics. Suppl 5: S132–43. doi:10.1002/1521-186X(2001)22:5+<::AID-BEM1029>3.0.CO;2-V. PMID 11170123.
- Lee GM, Neutra RR, Hristova L, Yost M, Hiatt RA (January 2002). "A nested case-control study of residential and personal magnetic field measures and miscarriages". Epidemiology 13 (1): 21–31. doi:10.1097/00001648-200201000-00005. PMID 11805582. (primary source)
- Li DK, Odouli R, Wi S, et al. (January 2002). "A population-based prospective cohort study of personal exposure to magnetic fields during pregnancy and the risk of miscarriage". Epidemiology 13 (1): 9–20. doi:10.1097/00001648-200201000-00004. PMID 11805581. (primary source)
- Cao YN, Zhang Y, Liu Y (August 2006). "[Effects of exposure to extremely low frequency electromagnetic fields on reproduction of female mice and development of offsprings]". Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi (in Chinese) 24 (8): 468–70. PMID 16978513. (primary source)
- Huss, A; Spoerri, A; Egger, M; Röösli, M; Swiss National Cohort, Study (2009 Jan 15). "Residence near power lines and mortality from neurodegenerative diseases: longitudinal study of the Swiss population.". American Journal of Epidemiology 169 (2): 167–75. doi:10.1093/aje/kwn297. PMID 18990717. (primary source)
- UK National Grid EMF information site
- See Electric power transmission#Underground transmission for details and references.
- Linet MS, Hatch EE, Kleinerman RA, et al. (July 1997). "Residential exposure to magnetic fields and acute lymphoblastic leukemia in children". The New England Journal of Medicine 337 (1): 1–7. doi:10.1056/NEJM199707033370101. PMID 9203424.
- Park, Robert L (2000). Voodoo Science: The road from foolishness to fraud. Oxford, U.K. & New York: Oxford University Press. p. 160. ISBN 0-19-860443-2. Retrieved 3 March 2011.
- "Response statement to the issue of power-frequency magnetic fields and childhood leukemia" (PDF). Federal-Provincial-Territorial Radiation Protection Committee. 2005-01-20. Retrieved 2011-03-18.
- Lakshmikumar ST (2009). "Power line panic and mobile mania". Skeptical Inquirer 33 (5): 35.
- Maslanyj M, Lightfoot T, Schüz J, Sienkiewicz Z, McKinlay A (2010-11-05). "A precautionary public health protection strategy for the possible risk of childhood leukaemia from exposure to power frequency magnetic fields". BMC Public Health 10: 673. doi:10.1186/1471-2458-10-673. PMC 3091578. PMID 21054823.
- Ahlbom IC, Cardis E, Green A, Linet M, Savitz D, Swerdlow A (December 2001). "Review of the epidemiologic literature on EMF and Health". Environmental Health Perspectives 109 (Suppl 6): 911–33. doi:10.2307/3454653. JSTOR 3454653. PMC 1240626. PMID 11744509.
- Michelozzi P, Capon A, Kirchmayer U, Forastiere F, Biggeri A, Barca A, PeruccAdult CA (2002). "Childhood Leukemia near a high-power radio station in Rome, Italy". American Journal of Epidemiology 155 (12): 1096–103. doi:10.1093/aje/155.12.1096. PMID 12048223.
- Draper G, Vincent T, Kroll ME, Swanson J (June 2005). "Childhood cancer in relation to distance from high voltage power lines in England and Wales: a case-control study". BMJ 330 (7503): 1290. doi:10.1136/bmj.330.7503.1290. PMC 558197. PMID 15933351.
- "Electromagnetic fields and public health: extremely low frequency fields and cancer". Fact sheet No. 263. World Health Organization. October 2001. Retrieved January 23, 2008.
- Maslanyj MP, Mee TJ, Renew DC, et al. (March 2007). "Investigation of the sources of residential power frequency magnetic field exposure in the UK Childhood Cancer Study". Journal of Radiological Protection 27 (1): 41–58. Bibcode:2007JRP....27...41M. doi:10.1088/0952-4746/27/1/002. PMID 17341803.
- "SAGE first interim assessment: Power Lines and Property, Wiring in Homes, and Electrical Equipment in Homes"
- "Researcher warns of brain cancer risk from cellphones". New York Times. July 24, 2008. Retrieved November 24, 2010.
- "Health risks from the use of mobile phones". Toxicol. Lett. 120: 323–331. 2001. doi:10.1016/S0378-4274(01)00285-5.
- "Animal carcinogenicity studies on radiofrequency fields related to mobile phones and base stations". Toxicol. Appl. Pharmacol 207: S342 – S346. 2005. doi:10.1016/j.taap.2005.04.032.
- "Epidemiological evidence for an association between use of wireless phones and tumor diseases". Pathophysiol 16: 113–122. 2009.
- "What are the health risks associated with mobile phones and their base stations?". Online Q&A. World Health Organization. December 5, 2005. Retrieved January 19, 2008.
- "Electromagnetic fields and public health: mobile telephones and their base stations". Fact sheet N°193. World Health Organization. June 2000. Retrieved January 19, 2008.
- Health and Environment - Science Milestones
- Information page on electromagnetic fields at the World Health Organization web site
- Biological Effects of Power Frequency Electric and Magnetic Fields (May 1989) (over 100 pages)
- CDC - Electric and Mangetic Fields - NIOSH Workplace Safety and Health Topic