| STOA No Information 5 / 2001 | | |
| European Parliament Directorate General for Research - Directorate A STOA - Scientific and Technological Options Assessment ELECTROMAGNETIC FIELDS AND HEALTH Under the precautionary principle [1] , the competent authorities should focus its efforts on protecting people against risks of damage from exposure to EMF [2] . As demonstrated by the scientific literature, studies in this area are too recent to be able to pinpoint the effects of long-term exposure to electromagnetic radiation. Although the effects in the short term have already been identified, the scientific community is still far from the identification's long-term effects. The experiments carried out in specialized laboratories have already pointed to some possible consequences of prolonged exposure to EMF, but it is still too early the question could be said to be resolved. Introduction Whenever it is produced, transporting and consuming electricity creates electromagnetic fields (EMFs), invisible lines of force that surround all electrical devices. The electromagnetic field is a combination of two types of fields: an electric field and a magnetic field. Power lines, electrical installations and electrical appliances and electric fields that produce magnetic fields. The electric and magnetic fields have different properties and perhaps also cause biological effects in different ways. It must be said that while one can easily screen or reduce the intensity of electric fields through conductive objects (eg. trees, buildings and human skin), the intensity of the magnetic field decreases away from the only source of emission. Around equipment and power lines are both electric and magnetic fields. The interest and research has recently focused on the potential effects of exposure to magnetic fields on health. The levels of human exposure to electromagnetic radiation are determined by measuring the specific rate of absorption, known as SAR (Specific Absorption Rate). The SAR indicates the amount of energy absorbed by the body, and is commonly expressed in watts per kilogram (W / kg). 1. - Sources of exposure The main sources of exposure to electromagnetic fields are listed below. It should however be noted that any device powered by electricity produces electromagnetic fields: the electric shaver, vacuum cleaner, hair dryer, radio, ironing equipment, a copier, refrigerator, tape recorder, TV, microwave etc.. 1.1. - Mobile phones and base stations The main sources of exposure are mobile phones and base stations, which emit radiation [3] radio frequency (RF) [4] . In both cases, the exposure levels generally decreased as the distance increases from the source. Regarding mobile phones, exposure affects particularly the part of the head which he approached the device, or various body parts closer to the phone are necessary on the use of hands. With regard to radiation from base stations, public exposure will cover the whole body but normally with intensity levels well below those achieved by the cell. 1.2. - The overhead cables and ions [5] recently developed some alarm on the role of ions or charged particles may have the increased risk for cancer in people living in near high voltage cables. This type of power lines it produces charged particles that attach to the particulates and contaminants in the air which, in turn, attach themselves to people. The agent pollutant is then deposited on the skin or inhaled, in which case fixing the lungs by virtue of his office. The high voltage cables are therefore not dangerous in itself, but because their presence attracts and concentrates the pollutants emitted by car exhaust, etc.. 1.3. - Train secondary The media and television have spread many scare stories about families living in the vicinity of secondary stations that have contracted diseases. The figure is surprising, since the sub-stations are not that big a source of electrical or magnetic fields you could imagine: on the contrary, there are far more important sources of EMFs within each house. 1.4. - Cables Wherever there is a flow of electrical current generates a magnetic field, according to this basic principle of all live cables create magnetic fields. Often the electrical cables underground greatest concern because they are very strong currents flowing through them. These cables are buried under the sidewalks or beneath the road surface and has a typical operating current ranging from 100 to 550 A. The differences are related to various types of cables used, in general, the operating voltage of the cable is irrelevant because a cable that works at 230 volts can lead to the same magnetic field of one working at 11,000 volts, if the current that flows is the same. At even higher voltages can be found some other differences. With the cables have a voltage of 33,000 volts, as well as with almost all the cables that work at voltages higher than this value, it is normal practice to combine three 3 single wires in one cable. Normally, cables are laid, leaving a space between each other, but this only adds to the intensity of magnetic fields, compared to what would be generated by placing the wires together. 1.5. - Transport The vehicles are not exempt from the electric and magnetic fields, since the electricity is used both as a source of energy for operating the control mechanisms. Trains and streetcars powered by overhead lines will create electric and magnetic fields along the length of the cables. Similarly, even where the energy is supplied to the ground, on a track electrified, they produce electromagnetic fields across the length of the line. 2. - What damage can be caused by EMF? in the literature on terms which often appear to EMF interaction, biological effect, risk and harm. When a living organism is exposed to an electromagnetic field, there is a ' interaction between the field strength and current and electric charges in the tissues, and resulting in the so-called biologic effect o. However, the biological effect is not necessarily a dann or, the damage occurs when the biological effect of compensation exceeds the biological organism. The risk is the probability intrinsic to a given damage occurs. The effects caused by exposure to electromagnetic fields can be classified as acute or cronic i: acute effects are always associated with a specific threshold, above which produces immediate and objective. Absence of chronic effects, neither objective nor immediate, you can also talk about long-term effects. 2.1. - The mechanism of interaction The electromagnetic fields produced pairs in the molecules, which can cause the migration of ions from positions Disturbed vibrations related charges, and rotation and reorientation of bipolar molecules such as water. These mechanisms are not able to produce observable effects following exposure to low frequency EMF, as they are rendered ineffective by thermal random. In addition, the response time of the system must be fast enough to allow it to react before the end of the interaction. Both issues involve the presence of a threshold (below which no observable reaction does not occur) and a cut-off frequency (above which there is no reaction observed). In general, following exposure EMF, the energy is deposited and distributed in an extremely unequal in the body. As for the energy absorbed by the human body, we can distinguish four categories of electromagnetic fields: __ frequencies from about 100 kHz to less than 20 MHz: the energy absorbed from the trunk decreases rapidly with decreasing frequency, as may occur significant uptake dependent on the neck and lower limbs; __ frequencies in the spectrum from about 20 MHz to 300 MHz: you can record a relatively high absorption throughout the body, with values \u200b\u200beven higher if we consider the partial body resonances; __ frequencies Around 300 MHz to some GHz: there is a significant uptake and non-uniform at local level; __ frequencies above about 10 GHz: the energy is absorbed mainly by the superficial layers of the body. 2.1.1. - Function cell The cell membranes of living organisms have a natural electrical charge, which is essential for the normal functioning of human tissues. This position is extremely sensitive to magnetic fields of very low intensity. The radiation from frequencies not existing in nature can change the location of molecules and damaged, altered metabolism. First, a process of chain reaction will cause an alteration in the electrical stability of the organism, affecting cell polarization. The resulting imbalance could alter hormonal activity, affect the synthesis of genetic material, interfere with the flow of substances through cell membranes in and out and change the behavior of cancer cells. 2.1.2. - The formation of free radicals [6] The mechanism behind the onset the damage involves the formation of free radicals, which damage proteins and cell membranes, maim genes and DNA, antioxidants to reduce levels of hormones, like melatonin, affect the biochemical and enzymatic processes essential to the conduct of the normal physiological functions and disturb the normal transmission of electromagnetic energy in the muscles. 2.1.3. - Stimulating the production of histamine Mast cells (cells that secrete histamine and other substances) are destabilized by free radicals. Studies have shown that mast cells exposed to radiation in radio frequency secrete twice as much of histamine. 2.1.4. - The alteration of calcium levels radio waves and their destructive agents, free radicals, alter calcium levels in the body, especially those affecting the central nervous system, brain and heart. It is believed that the level of calcium (and possibly magnesium) within cells decreases causing damage to the development, reproduction and cell division, as well as the exchange of signals between the outside of the cell and its nucleus. 3. - Perceived level of public risk associated with EMFs Technological progress, in the broadest sense of the word, has always been associated with various hazards and risks, both alleged and real, industrial, commercial and household resulting in the formation of electromagnetic fields (EMF) are no exception. Worldwide, the public looks with fear negative health effects that may result from exposure to EMFs generated from sources such as power lines, radar, mobile phones and base stations, especially in children. For this reason, in some countries are firmly opposed the construction of new plants and electricity distribution networks for mobile telephony. Recent history has shown that the lack of data on the health effects of technological change sometimes is not the only reason why the public opposes such innovations. The lack of attention to the differences in risk perception inadequately represented in the information in the scientific community, governments and industry to the public. 3.1. - The dangers and risks to health To understand the risk perception by the population, it is important to distinguish between a hazard and a risk to health. A danger can be an object or set of circumstances that may potentially endanger the health of a person; the risk is the possibility (or probability) that a person suffers damage from a particular hazard. The EMF can be potentially dangerous and the risk to the health of individuals depends on the levels of exposure. 3.2. - The perception of risk There are several factors that influence the decision of individuals to run or not a particular risk. Usually, people perceive the risks as negligible, acceptable, tolerable, or unacceptable, and compare them with benefits, which should be much greater than its risks. These perceptions may depend on the age of persons, gender, cultural background and level of education. The nature of the risk can lead to different perceptions. The investigations have identified a series of dichotomous pairs of a given situation, as listed below, which generally affect the perception of risk. The first factor tends to increase the torque, the other to decrease the extent of perceived risk. 3.2.1. - Exposure to involuntary / unintentional exposure This is an important factor in the perception of risk, especially in the case of sources electromagnetic radiation. People who do not use mobile phones perceive as high risk coming from the fields to radio frequency (RF) emitted by the relatively low base stations of mobile phones. However, those who use a mobile phone generally perceived as low the risk posed by radio frequency fields generated by mobile phone they use for free choice, although it emits radiation much more intense. 3.2.2. - Lack of personal control / feeling of having the situation under control If people can not express their views regarding the installation power lines and base stations for mobile phones, particularly in the vicinity of their homes, schools or playgrounds, they tend to perceive the high risk associated with facilities generating EMFs. 3.2.3. - Family / unfamiliar Familiarity with a situation, or the feeling of understanding the technology help to reduce the level of perceived risk. This increases when the situation or technology, like that of EMC, is new, strange or difficult to understand. The perception of the degree of risk can increase significantly if there is an incomplete scientific understanding of the potential effects on health caused by a situation or a particular technology. 3.2.4. - Feared / not feared Some diseases and conditions such as cancer, acute pain and persistent disability are feared more than others. Therefore, even a slight chance of developing cancer, especially in children due to exposure to electromagnetic waves of particular attention in public. 3.2.5. - Injustice / Justice If people are exposed to radio frequency fields generated by base stations of cell phones, but do not have a cell phone, or if they are exposed to electric and magnetic fields produced by a high-voltage transmission line that supplies electricity to their community, consider the situation unfair and are less likely to accept the risks associated with it. In the case of people who do not own a cell phone, for example, exposure to radio frequency fields from mobile phones base stations can be perceived as a high risk for the following reasons:
4. - Personal Protection The EMF exposure is cumulative. Our bodies can withstand a certain amount of radiation coming from electrical installations and electrical and electronic equipment found in homes. Another geopathic stress, such as that coming from radio frequencies, from high tension wires, or by the flow of groundwater may be the straw that breaks the camel's back. In fact, any other harmful source will add to the load and destabilize the body. It can not be considered in isolation, no single source is necessary to do everything possible to reduce the overall load, while improving the body's vitality and efficiency of the immune system. 4.1. - Strengthen the immune system through diet, diet antioxidant, detoxifying and fat is important because high levels of saturated fat increases the activity of free radicals, which is why you should avoid consuming foods fried, and we recommend that you eat any food containing pectin (found in apples) and algae meal, contributing both to protect the body by binding with toxins. you should eat a lot of broccoli sprouts Brussels, cabbage, cauliflower and watercress (preferably organic). It is also advisable to use oils such as sunflower, safflower, olive and canola, and to recruit derived from fermented milk such as yogurt and buttermilk, containing Lactobacillus and other bacteria that protect the gastrointestinal tract. It is also recommended to supplement your diet with antioxidants like vitamins A, C and E, in addition to calcium and magnesium, and trace elements such as selenium, germanium and vanadium, which inhibit the formation of free radicals. 4.2. - Specific actions for personal protection The most important thing is to be aware of the risks and take them seriously, although this is difficult, because the electromagnetic waves are odorless, tasteless, colorless and silent, and seem not to pose a risk until it is reflected. We can minimize your exposure: - limiting the use of wireless telephones and mobile phones. - staying away from the microwave and approached only when absolutely necessary. - Do not allow children to sit too close to the television or computer screen (VDU) [7]. - Sleeping in the area of \u200b\u200bthe house farthest from the cables of light, sources of radio waves, etc.. - Do not place the television or computer on the wall adjacent to the bed. - Sitting well away from the TV. - Avoiding devices that require radio waves or emits radiation of any kind. - unplugging all electrical appliances when not in use. 5. - The monitor (VDU) and our health not a VDU is just a monitor, similar to the television screen, which displays information sent from a computer rather than the signals transmitted by a TV repeater. When they were introduced for the first time in the workplace, the VDU were considered as the cause of many health problems, such as headaches, dizziness, fatigue, cataracts, problems during pregnancy and flare. There have been several scientific studies to identify possible health effects of electromagnetic fields. WHO [8] and other agencies have considered several factors, such as air pollution, work-related stress and ergonomic issues, such as posture and the way to sit at the computer. These studies (see below) have suggested that the working environment, not emissions of VDU EMFs could be a determining factor in any health effects associated with use of VDU. A brief review of the scientific discoveries made:
- Skin Effects. were carried out case studies of people who showed abnormal symptoms such as rashes or itching, but it was not possible to relate these symptoms to EMF emissions of VDU. Laboratory tests conducted on people with such symptoms have ruled that they were the result of exposure to EMF radiation. 5.1. - Protective Measures The fear that the waves radiated by VDUs cause adverse health effects has led to a proliferation of products that should provide protection against the harmful effects of these fields and radiation, including special protective clothing, protective shields or devices "that absorb the radiation" to apply to the VDU. Apart from the screens that reduce glare (causing eyestrain), WHO recommends the use of protective equipment, as EMC and radiation are only a small fraction of the permissible exposure limits based on international standards. However, would be desirable to give some helpful advice to avoid the effects of temporary and long term. Given that the eye strain increases with decreasing distance from the monitor, most experts recommend to make some minute break for every hour spent in front of the screen. You should also pay special attention to lighting (both natural and artificial) When using a monitor, you should always make sure that all light sources are at 90 degrees to the screen in order to prevent the occurrence of annoying reflections on it resulting eye fatigue. 6. - Mobile phones and health Mobile phones are low power radio devices that transmit and receive MW radiation with frequencies between 900 MHz and 1800 MHz Some of the energy of radio waves emitted by mobile phones is absorbed by the user's head, especially the superficial tissues . The exposure guidelines with regard to cell phones are therefore expressed in terms of energy absorbed in a small tissue mass of the head. The definition of guidelines SAR is useful to tell the public what level of radio waves or other electromagnetic waves emitted by electrical appliances can be considered safe. ICNIRP [9] set the SAR limit for the population 2 watts per kilogram (W / kg). It has recently conducted a research on the SAR from EMC Technologies in Australia, (commissioned by K-Tip Magazine, Zurich). The findings were reported by the Sunday lTimes December 3, 2000. The SAR identified by the research of EMC Technologies are: Phones SAR in W / kg Benefon Twin Dual Bosch GSM 909 0.81 1.01 The SAR is measured in watts of radiated energy, where the SAR limit is a threshold of absorption measured heat for each gram of brain tissue. Many scientists believe that SAR standards should not be used as
6.1. - Measures to protect The symptoms most frequently reported by users of mobile phones are without apparent cause headaches, vision problems and hearing, feelings of nausea or dizziness, numbness or tingling in the skin and reddening of the face and neck . Although there is no scientific evidence that radiation from mobile phones can be harmful, it was not even proven that they are harmless. If you were to discover that the emissions electromagnetic frequency range of mobile phones are causing problems, then the use of these devices by keeping so close to the head gives rise to concerns clearly. There are a number of features that users of mobile phones can put into practice if they are worried about possible risks to their health:
Great concern was also expressed by those who wear a pacemaker or a hearing aid. How should they behave? The brands and models of pacemakers are significant differences in levels of immunity to GSM signals. People who wear a pacemaker and want to use a GSM phone, consult your cardiologist or doctor, which can then:
sources of interference to hearing aids can load a variety of sources such as fluorescent lights, computers and other electronic devices, including mobile phones. The level of interference varies greatly depending on the type of hearing aid. In general, older and more cumbersome undergo more interference, while the most recent hearing aids on the market are already protected against interference from mobile phones and are constantly developing new standards for compatibility and new acoustic products. Who wears a hearing aid, fearing the consequences of using the phone, take the following precautions:
As long as there will be no evidence on possible health risks, you must take precautions for the use of mobile phones. 7. - The power of information Suppose that can be proved to certain that radiation from mobile phones causes cancer: slow the spread of the news as little as six months could mean a lot in monetary terms. As has been demonstrated in the debates on tobacco, BSE, and global warming, large industries are unwilling to passively accept the scientific findings, when they go to hit their best interests. What is good for the budget of the companies is not always good for public health. Take the example of the work of two scientists, funded by a European telecommunications company. Their first experiment has yielded important results and has attracted the attention of experts in telephony wireless, but few have access to the original study. The public was excluded, as well as the scientific community in general. Only the telecommunications companies had access to data, which were shared with a few others. In doing so, they lost a year and a half, in which other researchers could use this knowledge to refine their investigations. Clearly, the issue of health effects of EMFs is too complex to be resolved in a single laboratory that operates in isolation. But when the industry gets advanced knowledge on the results of a search, has a greater power of influence on subsequent developments. This in turn affects the policy decisions concerning the timing and funding of research. The inevitable consequence is that the media and the public do not have the confidence to trust the statements issued by the company. To complete the record of conflicts of interest arise in this case it is worth mentioning the role played by a famous consultant. The newspaper that has been subjected to study in question is Radiation Research, a leading magazines that deal with health studies on RF / MW, and the consultant and co-director, with primary responsibilities in relation to non-ionizing radiation, but he works with wireless handset manufacturers in different countries. This, of course, leads to a conflict of interest: it is a fact rather negative that the consultant is paid by the industry of mobile phones and acts as a repository of scientific information. The companies producing mobile phones and their advisers should not have competence in preview of search results. And 'there must be a condition of equal access to information as long as you do not get this balance, the private interests continue to enjoy an unfair advantage. communities feel they have the right to know what is proposed and designed with respect to the construction of EMFs that may be harmful to their health, and ask to have some measure of control and to take part in decision-making. Until you will create an effective public information and communication, involving scientists, governments, industry and population will continue to distrust and fear the new technologies EMC. Author: Federico BRUCCIANI under the supervision of CHAMBERS Graham, Head of STOA Unit. The statements included in this notice STOA do not necessarily reflect the position of the European Parliament. Management A Division Environment, Energy and studies, STOA European Parliament L-2929 LUXEMBOURG l Fax: (352) 4300 2771 8 l Or the Rue Wiertz 60 lB-1047 Brussels Fax : (32) 2 2844980 | ||
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