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Electromagnetic radiation

Because electromagnetic radiation is invisible, not everyone appreciates how powerful and dangerous it can be.

Levels of electromagnetic radiation (EMR) have increased significantly in recent years, and the World Health Organization has acknowledged the need for strict safety standards and for continued research into the potential adverse health effects. According to some scientists, the environmental impacts of EMR are potentially catastrophic for life on Earth.

There are various types of EMR, including radio waves, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays.

Electromagnetic radiation is able to spread almost everywhere. In a vacuum, EMR travels great distances without weakening. It retains its penetrative capacity in a gravitational, material environment, although it experiences some modification. It may have varying degrees and be of varying strengths. Human beings are generally unable to detect it, unless a high-power emission source generates perceptible heat. Powerful electromagnetic pulses can disable electronic devices and equipment.

Electromagnetic waves can have lasting impacts on human health and may even be fatal, despite the fact that the immediate, short-term effects may be relatively pain free. Studies have shown that exposure to electromagnetic radiation — even relatively weak levels — can cause cancer, memory loss, Parkinson's disease and Alzheimer's disease, and can even trigger suicidal behaviour. Magnetic fields are particularly dangerous for children and pregnant women. Electromagnetic radiation alters the status of male hormones and is particularly dangerous to the external reproductive organs.

In recent years, the number of EMR sources and their frequencies have increased dramatically in urban environments, and they continue to rise. They include cellular communication systems, police traffic radar devices, television antennas and radio transmitters. Electrical equipment used in buildings (transformers, cables etc.) produces electromagnetic fields, which contribute to EMR in living areas that are already exposed 24 hours a day to radiation from refrigerators, irons, vacuum cleaners, electric cookers, microwave ovens, televisions, computers and many other devices.

Areas in the vicinity of power lines are at increased risk.

In Belarus, the general Sanitary Norms, Rules and Hygienic Standards include requirements with respect to electromagnetic fields in workplaces. These set the hygiene standards for exposure, in the course of employment, to electrostatic fields, constant magnetic fields, industrial-frequency electromagnetic fields (50 hertz), and electromagnetic fields with a frequency range between 10 and 30 kilohertz.

Computers are one of the most common sources of EMR. Few people are aware that most radiation from a computer comes not from the monitor screen, but from the back of the computer. To avoid irradiating other people in a shared office, computers should not be placed in the centre of the room.

There are other misconceptions surrounding the safety of portable computers. Although there are no measurable X-ray emissions from liquid crystal display (LCD) screens (unlike earlier computer monitors based on cathode ray tube technology), they do emit a wide spectrum of EMR. Voltage transformers, circuit breakers and other pieces of electrical equipment used to display information on an LCD screen can generate electromagnetic fields. In addition, portable computers are usually located far closer to a user’s vital organs: It's worth thinking about the possible consequences before sitting a laptop in your lap.

Research has shown that certain cell phone models produce a magnetic flux density of up to 7 watts per square centimetre (W/cm2) at a distance of up to 5 cm from the antenna, which is several thousand times higher than the permitted limit of 100 microwatts per square centimetre (µW/cm2). Mobile phones are the most harmful of all household devices, as a phone antenna generates a large flow of EMR close to a person's head during use. A stream of waves with a frequency between 400 and 1,200 megahertz (MHz) irradiates the brain, while the energy density is quite high, at several hundred µW/cm2

It is not yet possible to predict all the adverse biological impacts of EMR from mobile phones. Many aspects of the problem are not addressed in the current literature and require further research. In this regard, according to the recommendations of the World Health Organization, it is advisable to adhere to preventive policies and minimise the amount of time spent using cellular communication devices.