The omnipresence of electrical appliances in our daily life is a cause for concern. To date, no scientific study has succeeded in demonstrating the harmfulness of non-ionizing electromagnetic fields. Some studies have uncovered statistical correlations, but fail to explain the causal link. When in doubt, the precautionary principle is applied.
Biological effects and harmful effects
The biological effects of non-ionizing electromagnetic fields on our body are not necessarily harmful to health.
A biological effect is often the simple expression of a spontaneous regulation of the body in response to an external stimulation: for example, the skin reddens on contact with the cold and the ear warms up in contact with the phone.
Electromagnetic fields encountered daily in the environment or at home are generally extremely low frequencies well below the threshold at which harmful effects occur (100 mA/m²).
Extremely low frequencies (ELF)
The lower the frequencies, the greater the differences between the electric field and the magnetic field.
The electric field does not pass through the body (or to only a slight degree) and can easily be blocked by a wall, vegetation, etc.
Near a high-voltage power line, we can observe some sensations that are related to the electric field:
- superficial tickling of the skin
- tingling
- slight electric shocks (when touching a metal object near a high-voltage power line)
- crackling noise (when it is raining near a high-voltage power line).
The effects of the magnetic field of high voltage power lines are more controversial. A low but prolonged exposure may increase the risk of childhood leukemia without any biological mechanism having been demonstrated to date. In fact, there is currently no scientific consensus on the causal links between ELF electromagnetic fields and childhood leukemia.
Low frequencies
At low frequencies, electric and magnetic fields generate low-intensity currents that flow around the body, called “induced currents”.
These currents are already naturally present in the body. But beyond a certain intensity, much higher than is common in our daily life, the induced currents can cause the stimulation of excitable tissues (flash of light, contraction of the muscles etc.).
Radiofrequencies
The electromagnetic fields of radiofrequencies can have a thermal effect: the body absorbs radio waves that it converts into heat.
The magnitude used to represent energy to heat conversion is the Specific Absorption Rate (SAR) which is expressed in Watt/kg.
Above 4W/kg, these thermal effects can be harmful. The onset of the thermal effects of radiofrequencies determines the exposure limits (SAR: 0,08 W/kg, or 42 V/m at 900 MHz).
Ionizing radiation
Ionizing radiation damages tissues and organs depending on the dose received or absorbed (Gy).
Beyond certain thresholds, ionizing radiation can alter the functioning of tissues and organs and produce acute effects:
- rash
- hair loss
- radiological burns
- acute radiation syndrome.
The threshold for the occurrence of acute radiation syndrome is around 1 Sv.
The damage depends on the type of radiation and the sensitivity of the different tissues and organs. As ionizing radiation increases, the dangers also increase.
Electromagnetic hypersensitivity
Electrohypersensitive people complain of symptoms which they attribute to the proximity or use of equipment generating electromagnetic fields of different frequencies (low frequency and radio frequency range). The reported symptoms are very diverse, such as headaches, tiredness, sleep, digestion, concentration and memory problems, anxiety and depressive tendencies, cardiac arrhythmia, muscle pain…
To date, there is no specific profile of symptoms that allows a diagnosis. The symptoms can be similar to other disorders or diseases and are frequently encountered in the general population.
The majority of exposure studies conducted to date have not demonstrated a causal link between non-ionizing electromagnetic fields and the symptoms described. But the research continues. Work is underway within Sciensano to create an exposure protocol that will accurately assess the relationship between exposure and symptoms. If you are interested in this project, do not hesitate to contact us.