EMF Exposure in the Modern Environment: A Comparative Historical Analysis

In 1927, when Hugh McBain reported cognitive effects from electromagnetic exposure, the global electromagnetic environment consisted of maritime radio, a handful of commercial broadcasters, and experimental military transmissions. Today, a person standing in any urban environment is simultaneously exposed to signals from cellular towers, WiFi routers, Bluetooth devices, IoT sensors, satellite constellations, smart meters, and radio frequencies they cannot identify. The question is not whether the environment has changed. It is by how much.

A Brief History of Electromagnetic Saturation

Era	Dominant Sources	Approximate Exposure Level
1927	AM radio, maritime radio, telegraph	Minimal. Most environments effectively free of artificial EMF.
1950s	AM/FM radio, television, early radar	Low. Signal density concentrated around broadcast towers.
1990s	Cellular (1G/2G), FM radio, television, microwave relay	Moderate. First generation of personal EMF-emitting devices.
2010s	4G LTE, WiFi (2.4/5 GHz), Bluetooth, smart devices	High. Multiple simultaneous sources within personal space.
2024	5G (sub-6 GHz + mmWave), WiFi 6E, Bluetooth LE, IoT mesh, Starlink/LEO satellites, smart meters, V2X automotive	Unprecedented. Continuous, multi-band, multi-source exposure in all inhabited environments.

The 5G Inflection Point

TFRi is not a 5G conspiracy organization. We note this because the cultural conflation of “concern about electromagnetic exposure” with “5G conspiracy theories” is itself an example of the stigma mechanism described in TFRi Working Paper 2024-03. It is possible to ask legitimate scientific questions about electromagnetic exposure without believing that 5G towers cause viral pandemics.

What 5G deployment does represent, from an electromagnetic environment perspective, is a qualitative change in the nature of human EMF exposure. Previous cellular technologies used relatively few, high-powered towers. 5G architecture — particularly in the millimeter wave bands — requires dense networks of low-powered small cells deployed on streetlights, utility poles, and building facades, often at intervals of 100–200 meters in urban environments.

The result is not necessarily higher peak exposure but qualitatively different exposure: continuous, omnidirectional, multi-frequency, and physically proximate. The person standing on a city street in 2024 is inside the transmission pattern of dozens of small cells simultaneously, in addition to their personal devices and the devices of everyone around them.

The Starlink Factor

SpaceX’s Starlink constellation — now comprising thousands of low Earth orbit satellites — represents the extension of continuous electromagnetic transmission to areas previously outside the reach of terrestrial infrastructure. There is, effectively, no place on Earth’s surface that is not now illuminated by artificial electromagnetic transmissions from orbit.

This is not a value judgment. It is a measurement. The electromagnetic environment of the planet has been fundamentally and permanently altered. Whether this alteration has cognitive effects is an empirical question that has not been investigated with anything approaching the rigor that the scale of the change would warrant.

The IoT Multiplication

The Internet of Things has introduced EMF-emitting devices into categories of objects that were previously inert. Refrigerators, light bulbs, door locks, thermostats, smoke detectors, doorbells, pet feeders, children’s toys, and mattresses now emit and receive electromagnetic signals. A typical household in a developed nation contains 15–25 IoT devices, each maintaining continuous or frequent radio communication.

The cumulative effect is that the home — historically the environment most insulated from external electromagnetic sources — has become a dense network of transmitting devices. The person who removes themselves from the urban electromagnetic environment by returning home encounters a different but equally saturated electromagnetic environment of their own creation.

The Exposure-Research Gap

The electromagnetic environment has changed by orders of magnitude since 1927. The research on the cognitive effects of electromagnetic exposure has not changed at all. The same research gap documented in TFRi Working Paper 2024-03 persists — and the gap between the scale of the environmental change and the scale of the research effort has widened rather than narrowed.

TFRi does not claim that modern EMF exposure causes cognitive harm. We claim that the question has not been adequately investigated, that the scale of the environmental change makes investigation urgent, and that the social stigma associated with the question — the “tinfoil hat” stigma — actively impedes the research that would answer it.

It is worth noting that the telecommunications industry generates approximately $1.9 trillion in annual revenue globally. The budget for independent research into the cognitive effects of the electromagnetic environment they create is, by comparison, approximately zero. TFRi does not draw conclusions from this disparity. We document it.

Implications for Cognitive Defense

Whether the modern electromagnetic environment requires cognitive defense is an open question. That the environment exists, that it has changed dramatically, and that it has not been studied, are closed questions. The answers are yes, yes, and yes.

TFRi’s certification standards are designed for the current electromagnetic environment — testing across 100 MHz to 10 GHz, with particular attention to the frequency bands that have expanded most dramatically in recent years. As the environment continues to evolve — 6G research is already underway, with proposed operating frequencies above 100 GHz — our standards will evolve with it.

Whether the appropriate response to an unprecedented electromagnetic environment is engineered shielding, psychological resilience, self-directed neurological modification, humor, or some combination of all four is a question TFRi continues to investigate. That an appropriate response is warranted seems increasingly difficult to dispute.