A study in Bioelectromagnetics tested whether the signal readings ordinary smartphones already collect can stand in for proper exposure measurements. Researchers in ETAIN, an EU-funded project on electromagnetic fields and planetary health, compared its 5G Scientist app against frequency-selective exposimeters in six European countries and Australia. For 4G, signal strength rose with measured exposure while signal quality moved inversely; for 5G only signal strength was associated, and the relationship was weaker and less consistent. The method estimates components of environmental network exposure, not total personal exposure or health effects.
This is the calibration step; in another article from the same team, the app's finished exposure maps were walked against reference meters in Utrecht and Basel, with strong agreement for 4G and only moderate where 5G was dense.
Quotes
"Smartphones track indicators of a reference signal to maintain network connectivity. These can serve as proxies for a subset of environmental radiofrequency electromagnetic field (RF-EMF) exposure from mobile networks."
"Parallel measurements were conducted across six European countries and Australia using frequency-selective exposimeters and the app."
"Associations of signal strength and quality indicators with exposure were analysed using log-linear regression models: (1) serving-cell level, relating exposure in the serving frequency band to indicators of the connected cell (Europe nā=ā2960; Australia nā=ā747); and (2) location level, relating indicators aggregated across network providers to environmental exposure from 4G-LTE and 5G-NR networks (Europe nā=ā61; Australia nā=ā48)."
"For 5G-NR, only signal strength was associated with exposure, with weaker and less consistent relationships than for 4G-LTE."
"These findings support using smartphone signal indicators to estimate components of environmental RF-EMF exposure, although further validation is needed, particularly for 5G-NR."
Location
š France, Netherlands, Switzerland, Spain, Greece, Germany, Australia
Estimating Environmental RF-EMF Exposure From Mobile Networks Using Signal Indicators Collected With the ETAIN 5G Scientist App
Sandoval-Diez et al. (2026) Bioelectromagnetics Journal Level 1ā
