When it comes to asking questions about the relationship between radio frequencies and health, most people ask themselves the same questions, this compilation attempts to provide an answer to these questions.
An electromagnetic field (EMF) is a combination of an electric field and a magnetic field. EMF’s may be static, that is, their size does not vary over time, or variable over time. In the case of static EMF’s, an electric field (magnetic) may exist without a magnetic field (electric). The situation is different regarding EMF’s which are variable over time, where an electric field is always associated with a magnetic field. A time variable electromagnetic field may be viewed as a wave propagating at the speed of light, associated with a time variable electric field and magnetic field. That is why when speaking of time variable EMF’s we are also speaking of electromagnetic waves or electromagnetic radiation. Although the word “radiation” is associated with negative effects, one must take into account that, in fact, it is a way of transmitting energy. The wave transports energy from one point in space to another and is characterised by its frequency and its wavelength. The frequency determines the energy that the electromagnetic wave transports. The greater the frequency the greater amount of energy the wave transports.
The frequency of electromagnetic waves varies over a very wide range of values. We are speaking about different types of waves or electromagnetic radiation depending on the frequency range. For example, we speak about radio frequency waves (those used in communications systems such as television, radio broadcasting, mobile telephony), microwaves, infrared, visible, etc. The set of all of these constitutes the electromagnetic spectrum.
A very important division within the electromagnetic spectrum is the division between ionising radiation and non-ionising radiation. This division is based on the energy transported by the wave and refers to whether this energy is sufficient or not to produce the breakdown in chemical links.
Ionising radiation can cause the breakdown of the links in the cells, affect genetic DNA and it is dangerous. Although the threshold to produce this breakdown depends on the molecule involved, in general, radiation is considered to be ionising when its frequency is greater than 10 to the power of 15 Hz, that is, to the part of the spectrum corresponding to ultraviolet radiation, X rays and gamma rays.
Non-ionising radiations, such as those used in mobile telephony and other communications systems, do not have sufficient energy to break the cellular links and for this reason it is highly unlikely that they might cause irreversible effects on health.
Yes, mobile telephone antennas emit radio frequency radiation, that is, non-ionising radiation. Mobile telephony uses radio frequency energy to transport information, in the same way as television and radio broadcasting. The antennas are similar to those used in TV and radio broadcasting but they emit at a lower intensity.
National and international organisms and committees agree that there is no causal relation between exposure to radio frequency electromagnetic fields and illnesses. Descriptive note no. 304 published by the World Health Organisation (WHO) establishes that even in long-term studies an increase in the risk of cancer due to exposure to radio frequency electromagnetic fields has not been detected, even at exposure levels which are much greater than those we are exposed to due to base stations (the so-called mobile telephone antennas) and wireless networks.
With regard to other effects, most studies have focused on the exposure to radio frequencies of mobile telephone users. Studies with human beings and animals in which brain waves, intellectual functions and behaviour after exposure to radio frequency fields, such as those generated by mobile telephones, have been examined; harmful effects have not been detected.
There is no evidence that alterations in sleep or in the cardiovascular function are brought about. Of all the data accumulated to date, none has shown that RF signals produced by base stations have harmful effects on health in the short or long term. Given that wireless networks (Wi-Fi) usually produce lower power radio frequency signals than those emitted by base stations, there is no need to fear that exposure to these networks is health-endangering.
Although radio frequency radiation is non-ionising radiation, limits related to the intensity (energy per unit of time) of the electromagnetic wave emitted have been set. This has been done to minimise the principal way in which the human body may be affected, which is a slight increase in temperature.
National and international organisms, their committees of independent experts, review the scientific bibliography published in prestigious, quality journals.
Safe limits are set for human beings based on results obtained in laboratory, clinical and epidemiological studies. The present exposure limits are those agreed by the World Health Organisation (WHO) and its International Commission for Non-ionising Radiation Protection (ICNIRP 1998) and the Institute of Electrical and Electronic Engineers (IEEE, 2005).
The Council of EU Health Ministers approved these guidelines in its Recommendation 1999 /519/EU. These levels are those that figure in Royal Decree 1066/2001 drawn up by Spain’s Industry and Health and Consumption ministries. The current limits are the ones accepted by the majority of developed countries.
The principal effect is a slight increase in temperature (the so-called thermal effects).
Their biological effects have long been known. One must not confuse biological effects, which are normal and known to be reversible, with harmful health effects. No important scientific study has established that antennas, within the emission limits set by law, cause irreversible health-endangering effects.
The most well-known effects of radio frequency (RF) electromagnetic fields (EMF) are thermal, that is, those that cause an increase in the temperature of the tissues exposed.
Numerous published studies have not observed non-thermal effects of RF EMF’s. One of the most exhaustive studies conducted to date is an epidemiological study of cohorts conducted by cancer researchers and epidemiologists from Denmark and the United States (Journal of the National Cancer Institute, Vol. 98, No. 23, December 6, 2006) of a population of 420,095 mobile phone users. This study concludes that there is no evidence of an association between telephone use and cancer, neither in the short or long term. The WHO, the EU and other organisms maintain ongoing research programmes owing to a principle of prudence and control of long-term exposure.
However, some researchers have cited other possible non-thermal effects that radio frequency EMF’s might cause in radio living beings, via biophysical mechanisms (ion movement, cell polarisation, membrane potentials, resonance or vibratory cell movements).
The fact is that, to date, it has not been possible to demonstrate that exposure to RF EMF’s causes non-thermal effects. Significant and conclusive biological effects have not been observed. In no case have harmful human health effects owing to these biophysical mechanisms been documented. This does not mean that they should continue to be investigated.
No because, as happens with other products and processes, they are subject to the regulations of international and national organisms, which rigorously monitor compliance. Their power of emission is limited by Royal Decree 1066/2001 and the exposure levels they generate are far below the limits considered safe by the World Health Organisation (WHO). The measurements carried out and the certifications issued in Spain confirm that the emission levels of antennas are hundreds or thousands of times below the limits established by law.
The Ministry for Industry, Trade and Tourism is competent in authorising and inspecting antennas. These installations are subject to a strict surveillance and monitoring system to ensure they comply with emission and exposure limits.
All of the competent national and international committees and organisations: WHO, ICNIRP (International Committee for Non-ionising Radiation Protection); EU (European Union), JRC, health authorities, technical reports produced by groups of independent experts such as the SSI (State radiation protection entity) in Sweden, the Health Council in Holland, etc., agree that there are no effects on health caused by exposure to emissions from mobile telephone antennas.
There is nothing to justify these measures. There are neither technical nor health reasons for doing so. Emission levels are far lower than those stipulated by current legislation, which, in turn, are based on the limits established by independent committees of experts.
The imposition of minimum distances would create confusion and generate unjustified alarm.
Is it advisable to decrease the number of aerials and/or move them farther from centres of population?
No. The greater the number of antennas the lower the exposure levels to radio frequency electromagnetic fields generated by the antennas as the power with which they must emit to ensure coverage is lower. If we move antennas farther from urban centres they will have to emit with greater power. Spain is the country that has performed most measurements, and they all verify that the exposure levels to which we are exposed are very low. This situation ensures that, in accordance with the scientific studies conducted to date, no health hazard exists for any population group.
No, because the emission levels are minimal under the antenna. The emission ray is horizontal and decreases with distance. Furthermore, the roof of the dwelling exercises an attenuating effect, possibly a hundred or a thousand fold.
Any citizen may verify the emission levels of the antennas closest to his or her home by consulting the website of the Ministry of Industry. The information is public, transparent and free.
There is no scientific evidence to suggest that mobile telephone use is harmful for the brain. The emission power of mobile telephones is very low and is limited by manufacturers. The maximum energy emitted by the mobile is directed towards the outside in the direction of the antenna. Part of the heat we feel is due to the pressure of the device on the ear. Moreover, the human body has sufficient mechanisms to dissipate the local increase in temperature caused by telephone use.
It has not been demonstrated that radio frequency electromagnetic fields cause the “electromagnetic hypersensitivity syndrome”. These people deserve full respect with regard to their concerns. Experiments conducted with people who claim to be hypersensitive to EMF’s have shown that these people are not able to detect, in experimental conditions, when they are exposed to EMF’s similar to those used in mobile telephony. At the same time, they respond very well if listened to and if they receive clear and objective information.
Yes. The World Health Organisation (WHO) and other competent organisations have assessed the long-term effects of exposure to the fields emitted by base station and wireless system antennas. See descriptive note no. 304 of the WHO
Moreover, the exposure levels measured all over Spain are hundreds or thousands of times below the limits considered safe for human beings; therefore, it may be deduced that there is no risk for the people exposed.
All pacemakers sold in the European Union must be manufactured according to compulsory electromagnetic compatibility standardisation regulations. This legislation sets the exposure levels that ensure that pacemakers work properly so that operation cannot be interfered with by the EMF’s we are exposed to in our daily life.
Are the mobiles that use the new technology known as 3G – UMTS or wireless telephony (DECTS) dangerous?
A recent report produced by the Health Council in Holland in 2007 (www.healthcouncil.nl) concludes that there is no evidence of effects on health caused by exposure to mobile telephony systems (UMTS and DECT).
In descriptive note no. 304, published in May 2006, entitled “Electromagnetic fields and public health: Base stations and wireless technologies“, the WHO comes to the following conclusions: “In view of the extremely low exposure levels and the findings of the investigation conducted to date, there is no scientific evidence that human exposure to the weak signals from base stations can cause cancer or any other adverse effect on health”.
Organisations and committees of acknowledged experts agree that, according to the scientific evidence, the current emission and exposure limits are safe. This assertion is compatible with continuing to investigate the effects of the radio frequency (RF) electromagnetic fields (EMF) although it seems unlikely there will be important findings. If there were a significant effect on health it would have already been detected. However, going on the principal of prudence and in the face of social demand regarding EMF risks research is still being done on the long-term effects, bearing in mind the concepts of chronic exposure and tumoral latency.
There are discrepancies in numerous areas of medicine and science but one must distinguish between science practised properly and science that does not used scientific methods. In order to assess good scientific work the following criteria, at least, must be taken into account:
- Dose/effect relation.
- Reproducible/consistent/coherent with other studies.
- Significance/power of the association. Relative and attributable risk. The factor is displayed.
- Biological plausibility: known mechanism.
- Study submitted for peer review (internationally acknowledged experts).
- Quality of the study.
The majority of studies published and disseminated on the possibly harmful effects of RF do not meet these criteria and are therefore not considered reliable or valid.
Because that is the very essence of scientific activity. Expert scientific opinion is based on the situation of scientific knowledge at any given moment.
On the other hand, the distorted perception of a section of the population has increased experts’ responsibility. A worried reaction to new technology is normal. However, if there were a clear effect it would have already been found. One should remember that radio and television stations have been emitting radio frequencies for many years and no effects on health have been detected. A principal of prudence in the face of a new technology makes it normal to monitor the effects of exposure to these electromagnetic fields.