Concerns about electromagnetic wave exposure persist amid the 5G rollout. Wireless networks have evolved over 25+ years—from GSM and 3G to 4G and now 5G. As experts in electromagnetic bioeffects at the University of Limoges, we break down the facts on this technology and health fears.
Modern telecom networks must deliver broad coverage for growing user numbers and blazing speeds for data-heavy content like video streaming. Voice calls have given way to bandwidth-intensive digital media.
Wireless systems rely on radio waves linking devices like smartphones to base stations (relay antennas). These invisible waves travel through air, unlike sunlight's higher-energy, higher-frequency waves.
When waves hit matter, some reflect, some penetrate and convert to heat—like in microwaves (900W) versus phones (<2W).
GSM started at 900 MHz; 4G spans 700–2600 MHz over tens of kilometers, needing dense antennas. 5G begins at 3.5 GHz (near 4G), then 26 GHz and >60 GHz for short-range.
Tech advances like power control and beamforming cut energy use by directing signals precisely.
Far-field: From distant base stations—levels drop with distance (field strength ~1/distance).
Near-field: From handheld devices like phones—higher local exposure near the body.
Waves cause energy absorption and heat at telecom frequencies. SAR (W/kg) measures this below 10 GHz.
ICNIRP guidelines set limits: 50x below whole-body 1°C rise in 6 min. Local limits protect heat-sensitive areas like eyes. Basic restrictions ensure no thermal effects; reference levels simplify compliance (e.g., >2 GHz: <0.08 W/kg whole-body, <2 W/kg local).
3.5 GHz mirrors 4G—similar penetration, no proven effects per global consensus. Ongoing reviews (e.g., ANSES) address children, pregnancy, chronic exposure.
Higher bands (26/60 GHz): Shallow penetration (3–6x less), focus on skin/nerves. Use power density (<10 W/m²). ANSES is analyzing data.
ANSES funds research via RNVEi; ANFR measures compliance and maps emitters. EU recommendations become French law.
