There are few other topics that spark such heated discussions: is cell phone radiation harmful or not?And what is that thing called "electrosmog" that pervades our whole daily life, from the TV screen to the high voltage line?Not even after 13,800 studies, of which the latest published a few days ago by the WHO (World Health Organization), was there any clarity on the possible consequences for health.And for the uninitiated, the quarrels between the experts are completely indecipherable.In today's article we certainly do not intend to provide a medical-scientific opinion on the issue but to analyze the main facts, we will ask ourselves what electromagnetic fields are and how they work and we will evaluate on average their importance device by device, comparing the numbers. with the parameters imposed by law.Before proceeding further it is necessary to make a brief excursus on what radio waves and EM (electromagnetic) fields are.Radio waves are formed by electric and magnetic fields, that is, by electromagnetic fields.They propagate at the speed of light and have a frequency ranging from 100 kilohertz (kHz) to 300 gigahertz (GHz).Electromagnetic fields can be divided into static fields and alternative fields.The first are, for example, the terrestrial field or the electric field such as that formed by rubber shoes on carpets.Alternate fields, also called waves, constantly change their state just like waves in water do.Sounds, light and gamma rays are also waves, just like cell phone radio waves.A few concepts are enough to describe the properties of radio waves:There are different types of emissions that can be assimilated to radio waves and with which we come into contact every day:To measure the intensity of an electromagnetic wave, one can look at the electric or magnetic field generated.For measurements, the easiest “field type” to locate is generally used.For example, in the case of electric current the magnetic field is often indicated, easily measurable with magnetic probes, while for radio transmitters the intensity of the electric field is used.For mobile phones it is possible to measure the heating effect or the SAR value.Usually, but not always, it is possible to convert values ​​to others using mathematical formulas.However, measuring the intensity of radio waves gives us no real indication as to whether they are dangerous or not.Despite the progress of the studies, more or less advanced depending on the type of radio waves, we still do not have an unanimous, all-round vision of the problem.In general, it is not wrong to adopt virtuous behaviors that can protect us from radiation.But be careful: if you think of the typical anti-radiation accessories these are completely useless as we have verified in our laboratories.The most effective protection from radio waves is to move away from the transmitting antenna.The impact of radiation significantly decreases based on distance following a trend that provides for a reduction in intensity proportional to the square of the distance.Electromagnetic waves interact not only with the human body but also with other devices: electrical devices malfunction when exposed to an "overdose" of radio waves, so much so that to protect people wearing pacemakers, a limit value has been set that no transmitter can overcome.Radio waves can also disturb TV reception.Smartphones and mobile phones The salient data concerning this category of devices are:Frequency - GSM networks: 880-960MHz and 1.7-1.88GHz;UMTS network: 1.900-2.710MHz.Transmitting Power - 1 Watt to 2 Watt.Modulation - GSM (pulsed at 217 Hertz), with UMTS CDMA signals (not pulsed)Limit values ​​The limit values ​​for mobile phones are set by the European standard EN 50361 and mainly consider the heating effect of radio waves.Since the consequences are only dangerous when the limit value is exceeded by at least 50 times, the authorities believe that when this value is respected there is no health risk.The dangers identified with mobile phone networks are to be found in the thermal effect, the athermic effect and the possibility of brain wave modifications.Thermal effect: When you make a phone call, your ear warms up mainly because you press the phone into it.Radiation contributes to this heating to varying degrees depending on the structure, antenna and transmission power of the mobile phone.This "calorific effect" is indicated by the SAR value.To prevent radiation from damaging the sensitive tissue of the eyes, this value must not be too high: they cannot exceed two Watts per kilogram of body mass, referring to a part of the body.The actual transmission power of mobile phones is usually lower than the maximum allowed.This is because the transmitters of mobile telephone networks regulate the power of the waves to the minimum necessary.Athermic effect: these are possible, but not always demonstrable, consequences of the use of cell phones.They can also occur at very low transmission powers.No one can tell if they are really harmful to health.Brain wave changes: Swiss researchers (Huber) exposed 16 candidates to pulsed radio waves from mobile phones, finding changes in brain activity.However, a similar study (Croft) found the opposite.According to the Swedish study Salford (2003), radiation from mobile telephony (GSM) damages nerve cells.It is a damage that can result in damage to the "blood-brain barrier" in humans: premature dementia and Alzheimer's the possible consequences.The German Federal Office for Radiation Protection, however, questioned this study, because the results contradict those of other research.Cancer: The Interphone study looked at the risk of brain cancer in 13 countries.The data collected between 2000 and 2004 did not reveal a relationship between cell phone use and cancer risk.Research promoted by Motorola in 2001 came to the same result.Damage to the genome: In 2009, a study by the US Society of Reproductive Medicine warned against damage to spermatozoa.Another research of 2010 (Falzone) has instead withdrawn the alarm.The REFLEX study of the years 2005 and 2008 found damaging breaks in the DNA strands, but it later turned out that a researcher had falsified the values ​​of the measurements.Despite this, this study is often cited.Advice Even if there is no reason to be alarmed, it is true that no one yet feels like saying that there are no dangers.Therefore, it is necessary to minimize the impact of radio waves: use a low-emission cell phone, always check the declared SAR value, and telephone with a headset to keep a safe distance from the antenna.The salient data concerning the antennas for the transmission of mobile phone data:Frequency - GSM networks: 880-960MHz and 1.7-1.88GHz;UMTS network: 1.900-2.710MHz.Transmitting Power - Up to 100 Watts, typically split between the different directions of the antennas.Modulation - GSM (pulsed at 217 Hertz), with UMTS CDMA signals (not pulsed).Limit values ​​There are very strict regulations for antennas in Europe.For Italy, the maximum values ​​are fixed as an electric field with an intensity of 41 Volt / meter (GSM 850 network), 57 Volt / meter (GSM 1800 network) and 61 Volt / meter (UMTS network).The same values ​​are, for example, also set in Germany.The potential dangers generated by these antennas are identified in their vicinity and, in most cases, concern situations that are more of a suggestive nature than actually linked to the effects of radiation.Thermal effect: is excluded due to high limit values.Athermic effect: many studies concern in particular the masts of the antennas, because they always transmit, unlike cell phones.Headache: According to research published in 2006 by some German doctors, there should be a relationship between the intensity of the field and the symptoms complained of by the people being tested - for example, headaches and sleep disturbances.In a recent cross-sectional study, a team led by Dr Breckenkamp (University of Bielefeld, Germany) questioned 4,150 people.In the presence of health disorders, the researchers measured radio waves, but low values ​​were found in the homes of all 1,808 people complaining of ailments.Statistically, it emerged that those who believed in the danger of mobile phone masts fell ill more often.The main data concerning the transmission devices used to monitor children are the following:445 MHz frequency for PMR models;868 MHz or 1.9 GHz for DECT models;2.4 GHz for video baby monitors.Transmission power 455 MHz PMR models: 500 milliwatts maximum;868 MHz DECT models: 10 milliwatts maximum;1.9 GHz DECT models: 250 milliwatts maximum;2.4 GHz models: 100 milliwatts.Modulation PMR models: phase modulation;DECT models: phase modulation (GFSK), pulsed;Models with video function: frequency modulation.Limit values ​​Baby monitors cannot exceed a SAR value of 0.08 Watts per kilogram (referred to the whole body) and do not even come close to these values.Babyphones can hardly be considered potentially dangerous due to the electromagnetic waves they generate.Thermal effect: Due to the very low transmission power and the large distance from the body, baby monitors are unlikely to have a warming effect.Also, devices in children's rooms only transmit when the little ones scream, so not continuously.Athermic effect: Dangers are often reported for baby monitors with DECT technology due to the pulsed transmission signal.However, there is no significant study that proves this, not even with regard to DECT phones.In reality, the dangers of baby phones are other: in many cases, for example, their soft antennas contain dangerous plasticizers.The cordless phones mainly used in the home take advantage of DECT technology and have the following typical values:Frequency 1,880 to 1,900 MHz. Transmission power Maximum 250 milliwatts with a power flux density of 20 microwatts / cm 2.The most recent DECT phones are “low radiation”: the base transmits only during conversations, while both the phone and the base lower the power to the minimum necessary.From this point of view, however, manufacturers do not exploit all the possibilities offered by technology.Modulation Phase modulation (GFSK), pulsed.Limit values ​​During a SAR measurement, a phone cannot exceed two Watts per kilogram of body tissue (value for one part of the body, ie the head).Since the measurement does not consider the maximum value, but the average value, the results show that cordless telephones only reach 4% of the limit values.This was also found in our measurements.DECT phones therefore beat mobile phones in a big way.Since people do not keep the bases close to their heads, the total value stands at 0.08 watts per kilogram - even this so far unbeatable.Given the premises, we can hardly think of potential dangers for cordless phones.However, let's analyze the individual items.Thermal effect: in the worst case, the average calorific effect (SAR) is less than 0.1 Watt per kilogram, therefore much lower than that of mobile phones and the maximum allowed by the regulations.In past tests in our laboratories it has been found that the SAR value during short pulses is around three Watts per kilogram.However, the pulses are so short (microseconds) that according to experts they cannot cause a heating effect.A single research, published in 2007 by the Dutch Health Council, specifically examined signals from DECT phones.The results were not clarified, because normal use does not lead to exceeding the limit values.Athermic effect: so far no researcher has been able to demonstrate the existence of effects other than heating ones.Brain tumors: in 2006, the so-called Interphone study investigated the possible increase in the risk of brain tumors in the presence of cordless bases too close, but without obtaining results.Cancer risk: 20 studies have addressed the general cancer risk of DECT phones.All were concluded without results or with controversial outcomes, because they are based on an insufficient number of cases or because the researchers carried out them with non-pulsed signals.Tips The calorific effect is very close to zero.Only green building consultants warn about pulsed signals from DECT phones.While the science has not yet come to a unanimous conclusion, those who want to protect themselves should use a low-radiation DECT phone.Wireless routers have now invaded the homes of all of us, also thanks to the integration of a WiFi antenna in the notebooks and systems we use.But what, if any, are the dangers associated with this technology?802.11b / g frequency - from 2,400 to 2,483.5MHz;802.11n - 2,400 to 2,483.5MHz and 5,150 to 5,725MHz.Transmitting power At 2,400 MHz: maximum 0.1 Watt radiated power;At 5,400 MHz: maximum 1 Watt of radiated power.Modulation Typically OFDM.Limit values ​​Since WLAN routers are not worn, the SAR values ​​for the whole body must be considered, according to which a WLAN device cannot exceed 0.08 watts per kilogram.More than routers and access points, in this case, it is necessary to pay attention to the proximity of the antenna integrated in the notebook, console or smartphone.Thermal effect: Due to the low transmission power and the distance between the WLAN devices and the body, heating effects are unlikely.In 2001, a study by the University of Bremen carried out at ten WLAN access points found flux densities whose maximum values ​​remained far below the values ​​established by law, even below the very strict preventive recommendations of the renowned Swiss Nova Institute.Only for WLAN notebooks and at distances of 10 to 20 centimeters, the researchers found values ​​above the precautionary limits.A clinical study conducted by TH Aachen in 2001 came to the same result.Athermic effect: Green building technicians report that WLAN signals pulsed at around 10 Hertz are exactly in the range of the brain's so-called alpha waves.However, there is no research that can prove any health implications.One of the ways to keep the phone away from our head is to use a Bluetooth headset.But are we sure that this transmission technology is no more dangerous than that used by the terminal during conversations?Frequency - 2.400 to 2.438MHz.Transmission power - Maximum 100 milliwatts, for hands-free kits;Maximum 2.5 milliwatts (class 2), for headsets.Modulation - Several methods employed.Limit Values ​​- The SAR value cannot exceed 2 Watts / kg.The signals are so weak that they are practically not measurableFrom the values ​​shown there are absolutely no dangers in using a Bluetooth headset.Athermic effect: up to now no specific study has been carried out on the signals linked to the increasingly widespread Bluetooth technology.Traditional household appliances work by exploiting the current supplied by the network lines installed in our homes.Frequency 50 Hz. Amplitude If the electric cables are laid correctly, the magnetic fields of the outgoing and return lines cancel each other out, but only when the two lines are separated by switches.Otherwise, electric fields are generated.The more current passes, the stronger the magnetic field.Especially that of vacuum cleaners, electric blankets, drills and cathode ray tube televisions.The latter produce a maximum of 20 microtesla at a distance of 30 centimeters.Fluorescent lamps reach about 0.4 microtesla at 50 centimeters away.The intensity of the electric fields of household appliances is very different, because they are also affected by other devices that are nearby.At a distance of 30 centimeters, 90 volts per meter were found for televisions, one volt per meter for power sockets and 0.1 volts per meter for electrical cables.Modulation None.Limit values ​​For the intensity of the electric fields, the legal limit of 5,000 Volts per meter is considered, for the magnetic fields 100 microtesla.Green building technicians recommend values ​​between one and five volts per meter and between 0.02 and 0.1 microtesla, respectively.However, there are few devices that respect them.Apparently the greatest risks are those connected precisely to the use of normal devices connected to electricity and to the lines made to ensure that this is available within the whole house.Irritations: At very high intensities, eddy currents irritate the nerves and organs.But only people in certain professions, such as locomotive drivers, are subjected to such high values.Brain functions: So far, no clues have emerged that lead to damage caused by magnetic fields.Breast cancer: 15 studies have recently been compared, for a total of 24,000 cases analyzed, without finding any relationship between magnetic fields and breast cancer.Alzheimer's: In 2004, the Swiss Nova Institute reported scientific analyzes that would have found a vague connection between low-frequency fields and Alzheimer's, even if only for people exposed for a long time to strong magnetic fields.Leukemia: As part of a workshop of the BfS (German Federal Office for Radiation Protection) held in 2008, researchers found that magnetic fields of 0.3 to 0.4 microtesla increase the risk of leukemia.It is a value achieved, for example, by a fluorescent lamp half a meter away.A biological explanation of the phenomenon has not been provided.Recommendations For “normal” current there are risks caused by the strong magnetic fields of high consumption household appliances, such as drills or cathode ray tube televisions that reach up to 90 Volts per meter.To protect yourself, you need to keep your distance from these devices.It is possible to use mains circuit breakers that disconnect the electric cable when there is no current consumption, for example at night in the bedroom.The pylons used to support the high voltage lines have a height from the ground so that the standards are respected.But some studies have shown that the risk of Alzheimer's disease for people living less than 50 meters away from a power line is higher.Frequency 50 Hz. Amplitude At 400 kilovolts a magnetic field of just under 60 microtesla is produced, which can vary with current flow.The intensity of the magnetic field depends on the distance from the line: at 50 meters it is 500 Volts per meter.Modulation None.Limit values ​​A maximum magnetic flux density of 100 microtesla is generally allowed.The electric field cannot exceed five Kilovolts per meter.The height of the pylons carrying the high voltage current allows these values ​​to be respected.Since the intensity of the fields decreases dramatically with distance, the impact is high only in the immediate vicinity of the tower.A 2008 study (Huss) found an increased risk of Alzheimer's for people living less than 50 meters from a power line.According to the German Federal Office for Radiation Protection, similar studies have been carried out on children and found an increased risk of leukemia even in the presence of weak magnetic fields.However, researchers have not been able to ascertain whether the cause of this could be the home electrical network.To shed some light on this, the Fraunhofer Institut is conducting a very specific animal study in the Hanover laboratory.