This section provides answers to common questions mobile and wireless networks. Typical exposure levels from wireless networks in public areas are small fractions on international safety guidelines. According to the WHO:
‘Considering the very low exposure levels and research results collected to date, there is no convincing scientific evidence that the weak RF signals from base stations and wireless networks cause adverse health effects.’
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Media reports in April 2007 claimed that a small German study reporting effects on bee behaviour when a digital cordless phone was placed near hives, was an indication that mobile communications might be a possible cause of Colony Collapse Disorder (CCD). CCD is being studied by a working group of the Mid Atlantic Apiculture Research and Extension Consortium (MAAREC)
. A FAQ produced by the working group and dated 9 March 2007 lists base stations as one cause that is not currently being investigated.
The United States Department of Agriculture
says that there is no link between mobile phones and CCD. They also quote Stefan Kimmel, the researcher who conducted the German study as saying that there is 'no link between our tiny little study and the CCD-phenomenon ... anything else said or written is a lie.' Many of the media reports included a statement attributed to Albert Einstein but it is uncertain whether he made the statement
In 1999, the WHO International EMF Project
, the ICNIRP
and the German Federal Office for Radiation Protection (BfS)
hosted a seminar on the effects of electromagnetic fields in the environment. A review produced after the seminar concluded that: 'Overall, it appears that the human EMF exposure limits recommended by the International Commission on Non-Ionizing Radiation (ICNIRP, 1998) would also be protective of the environment.
Some people have been concerned about claims of possible increased rates of disease among people living near to radio transmitters. These reports are sometimes described as clusters
.The World Health Organization
has addressed this topic:
'It should be noted that geographically, cancers are unevenly distributed among any population. Given the widespread presence of base stations in the environment, it is expected that possible cancer clusters will occur near base stations merely by chance. Moreover, the reported cancers in these clusters are often a collection of different types of cancer with no common characteristics and hence unlikely to have a common cause
Independent health authorities in Australia (Melbourne, 2006), France (Saint-Cyr-l’Ecole, 2004), Northern Ireland (Cranlome, 2003), Spain (Valladolid, 2001) and the USA (Lookout Mountain, 2004) have investigated suspected clusters near base station and other radio transmitters and found no evidence to link illness with either proximity to or exposure from radio transmitters.
Information on published studies can be found here
. In 2010 a systematic review of studies involving base station
type exposures was published in the WHO Bulletin
. The authors concluded:
'our review does not indicate an association between any health outcome and radiofrequency electromagnetic field exposure from MPBSs [mobile phone base stations] at levels typically encountered in people’s everyday environment.'
They regarded the evidence as strong for an absence of short term effects (such as non-specific symptoms) as it was based on randomized trials applying controlled exposure conditions in a laboratory. For long-term effects, there was less data and further research was recommended.
There are many technical challenges to conducting studies of populations living near base stations.
- Are the RF exposures in public areas high enough to induce a health hazard?
Measurements have found that the levels near base stations range from about 0.002% to 2% of the levels recommended in international guidelines.
- Do base station signals predominate over other environmental RF signals?
The total community exposure from all radio sevices includes: AM/FM radio, TV broadcasts, WiFi, emergency service communications, paging systems, radio communication links, cordless phone systems and so on.
- Is it possible to assess the exposure of an individual?
At ground level, radio signals from network antennas do not reduce uniformly with distance from the antenna. Importantly, distance alone is a poor estimate of exposure and should not be used in scientific studies. The levels are dependent on many factors including the antenna height, type and direction as well as transmitter power, radio signal absorption and scattering due to environmental obstacles.
There are some studies in the WHO's EMF research database
that report effects, however, it is not the quantity of experiments but the quality of the study that is important. Independent health experts have criticised many of the studies claiming effects for technical flaws such as poor exposure assessment, symptom-reporting bias or inadequate control of confounders such as age. In another example, an Austrian study
from 2008, has since been withdrawn as it was reported that no base station was active during the period of the claimed cancer increase.
The World Health Organization
states that '...there is no convincing scientific evidence that the weak RF signals from base stations and wireless networks cause adverse health effects.
' The UK Health Protection Agency
(now part of Public Health England) advises that: 'On the basis of current scientific information, exposures from Wi-Fi equipment satisfy international guidelines. There is no consistent evidence of health effects from RF exposures below guideline levels and no reason why schools and others should not use Wi-Fi equipment.
' The Wi-Fi Alliance
and the Health Physics Society
has also produced information on this topic. See also the GSMA booklet on WLAN/WiFi here
The consensus of many expert reviews
is that there are no health risks from exposures to radio signals up to the WHO
recommended international guidelines
. In November 2007, a paper published in the journal of the Australasian College of Nutritional & Environmental Medicine claimed a link between autism
and electromagnetic fields
. The GSMA is concerned that this paper could cause unnecessary alarm to the parents of autistic
children. The study is poorly described, has no control group and makes claims on causes of autism and actions of radio signals that have been rejected by health groups around the world.
Some people report a variety of symptoms (such as headaches, burning sensations, tiredness, concentration difficulties and dizziness) that they attribute to exposure to radio signals from mobile phones or wireless networks. This is sometimes termed electromagnetic hypersensitivity
(EHS). There have been several studies of exposures similar to mobile phones (Rubin et al, 2006
; Kleinlogel et al., 2008
; Wallace et al., 2010
) or base stations (Regel et al., 2006
; Eltiti et al.,2007
; Furubayashi et al., 2009
; Eltiti et al., 2009
). A systematic review (Rubin et al., 2010
) identified 46 blind or double-blind provocation studies involving 1175 self-reported EHS individuals and concluded that overall there was no relation between electromagnetic field exposures and reported symptoms.
The World Health Organization (WHO)
has concluded that while the symptoms are real there is no scientific basis to link the symptoms to exposure to electromagnetic fields
. Furthermore the WHO says that treatment of affected individuals should focus on management of the health symptoms and the clinical picture, and not on the person's perceived need to reduce or eliminate electromagnetic fields in the workplace or home.
There is misunderstanding of the status of EHS in Sweden. An expert group report in 2007
for the Irish government sets out the situation clearly. Electromagnetic hypersensitivity is not a recognised medical diagnosis and has not been accepted as a work injury in Sweden. In Sweden the focus is on the symptoms presented by the afflicted person (symptom diagnosis) and regardless of known or unknown cause for the condition. In Sweden the focus is on the symptoms presented by the afflicted person (symptom diagnosis) and regardless of known or unknown cause for the condition. In addition, most disability organisations, including The Swedish Association for the Electrosensitive, receive financial support. This fact has sometimes been misinterpreted as if electromagnetic hypersensitivity is a recognised medical diagnosis in Sweden.
The topic of EHS is also addressed in this YouTube