What is an electromagnetic field?
Electromagnetism is the branch of physics that studies the interactions between electric
currents and magnetic fields. Every electric current generates a magnetic field, and its
importance is proportional to the intensity of that current.
An electromagnetic field (an EMF) is the pairing of an electric field with a magnetic
field. The field influences electric charges at a distance, by attraction or repulsion.
The electromagnetic wave is a model used to represent the intensity of that field as a
function of time. Contrary to common belief, electromagnetic waves radiate: they do not
propagate physically.
Low frequencies
Between 1 Hz and 9 kHz. At home, most of the pollution sits at 50 Hz, the frequency
of the mains supply in the UK.
High frequencies
Between 9 kHz and 300 GHz. Most of the electromagnetic fog in our homes falls between
9 kHz and 6 GHz.
Artificial electromagnetic waves
The human body works thanks to billions of electric charge exchanges between atoms and
molecules. The nervous system itself is communication through electrical impulses. Every
cell functions through natural electromagnetic fields and electric currents.
We live permanently in a bath of natural electromagnetic fields covering a very wide
spectrum, from the lowest frequencies to the highest. Humans only see wavelengths between
380 and 780 nanometres. Despite the limits of our perception, these fields exist and are
biologically involved in life.
Some waves are human-made; we call them artificial. Low-frequency artificial waves have
spread since we learned to master electricity, thanks in particular to the ingenuity of
Nikola Tesla and Thomas Edison. High-frequency artificial waves arrived with wireless
communication (FM radio, Bluetooth, Wi-Fi, mobile telephony, television) and keep
growing under the impulse of connected objects and smart cities.
- Household wiring & appliances
- Wi-Fi routers
- DECT cordless phones
- Mobile phones & masts
- Smart meters
- Bluetooth devices
- Baby monitors
- Connected objects
Effects of electromagnetic waves on health
Electromagnetic waves have two different types of effect on the organism:
- Thermal effects: energy absorption inducing an increase of temperature in body tissue.
- Non-thermal effects: several phenomena that do not come from a temperature increase.
Thermal effects are the best documented and the most easily identified with our senses:
the burning sensation at the ear after a phone call. The field generated excites the
molecules and raises the temperature. The Specific Absorption Rate (SAR), in W/kg,
quantifies that absorption, and it is the unit used in exposure standards; it is the
figure quoted when you buy a phone.
Several scientists consider the SAR an inappropriate unit for defining protection values,
because it only accounts for thermal effects, while the biological effects are potentially
more harmful in the long run.
Biological effects of EMF exposure are harder to identify, but they are more insidious and affect the overall functioning of the organism.
What the Bio-Initiative report found
The Bio-Initiative report, led by independent scientists, is a meta-analysis (or study of studies) of around
2,000 scientific studies. It documents non-thermal effects that are far less widely known:
- Effects on the immune system
- Genotoxicity (DNA damage)
- Brain tumours
- Cell stress and oxidative stress
- Behavioural disorders
- Sleep disorders
Studies pointing the same way
| Study | Year | Led by |
|---|
| INTERPHONE | from 1999 | World Health Organisation |
| REFLEX | 2000–2004 | European Union |
| COMOBIO | 2003 | French research consortium |
| L’appel des 20 | 2008 | Twenty scientists, mostly cancer specialists, alerting on the health risks of mobile phone exposure |
Going further
To learn more about how exposure affects health, we recommend the books
Electromagnetic Man and Electromagnetic Pollution: International Safety Guide
(both listed on our resources page) and the research index at
emfanalysis.com.
What is electrosensitivity?
Electrosensitivity (electromagnetic hypersensitivity, or EHS) is a condition whose
proposed cause is exposure to electromagnetic waves. The World Health Organisation
recognises the symptoms as real, and classifies RF radiation emitted by devices in the
30 kHz to 300 GHz range as a possible human carcinogen (Group 2B).
No official study has yet listed and quantified the symptoms. The phenomenon is poorly
understood, but it is real. According to the Breakspear Clinic, which treats environmental
illnesses, electrical sensitivity affects roughly 1 in 1,000 of the population.
It appears to be triggered when the organism largely loses its capacity to defend itself
against these invisible aggressions, a dose effect. That is the argument for measuring
early: even if you feel well today, knowing your electromagnetic environment lets you act
before the burden builds.
See what an assessment covers
