6G: Progress with open questions?
6G: What do we know about technology, radiation and health?
6G is not simply meant to bring faster mobile internet. The coming generation of mobile communications is intended to combine communication, artificial intelligence, sensing, positioning and an enormous number of networked devices.
The International Telecommunication Union (ITU) calls it IMT-2030. In 2026, however, we are still in the middle of standardisation. How a future 6G network will actually be built, which frequency ranges will really be used on a large scale and how this will change the population’s real exposure has therefore not yet been fully decided.
Perhaps we should therefore not only ask:
What can 6G do?
But also:
What effects could such a comprehensive wireless infrastructure have on people and the environment – and do we already know enough about them?
There is no “one” 6G frequency
Mobile radio waves belong to non-ionising radiation. Unlike X-rays or gamma rays, they do not have enough energy to ionise atoms directly. The scientifically established relevant mechanism of action of high-frequency electromagnetic fields at sufficiently high intensity is the heating of tissue. Key elements of the current limit-value concepts are also based on this.
With increasing frequency, however, energy absorption changes. The WHO points out that higher frequencies penetrate the body less deeply. The absorbed energy is therefore increasingly concentrated in areas near the surface, especially the skin and eyes.
At first that sounds reassuring: less penetration depth means less direct exposure of deeper organs. But does that automatically mean all-clear? Or does it merely shift the question to skin, eyes and superficial tissue structures?
What happens in the body at higher frequencies?
As frequency increases, the penetration depth of electromagnetic waves decreases. Energy absorption shifts more towards the skin, eyes and tissue near the surface.
In public discussion, the impression sometimes arises that 6G is synonymous with terahertz radiation. It is not that simple. For IMT-2030, the ITU basically envisages a very broad spectrum – from frequencies below 1 GHz up to ranges above 100 GHz. Which of these will later actually be used for which applications is still the subject of research and standardisation. This, however, raises an important question: is our current knowledge of existing mobile frequencies sufficient to assess future forms of exposure as well?
Frequency is not the only decisive parameter. Transmission power, pulse structure, length of stay, distance, beamforming, number of transmitters, combination of different frequencies and personal use also determine actual exposure.
The WHO also sees a need for further research
For today’s wireless technologies, the WHO concludes that so far no adverse health effect has been causally linked to radio exposure within the applicable limits. At the same time, it points out that far fewer studies are available for higher frequencies. This is an important distinction.
Scientifically, “not proven so far” does not mean the same as “ruled out in principle”.
Especially for a technology that is not due to be introduced until around 2030, decades-long epidemiological studies of real 6G users cannot, by their nature, yet exist.
An old classification remains noteworthy
In 2011, the International Agency for Research on Cancer (IARC) classified radiofrequency electromagnetic fields in category 2B – possibly carcinogenic to humans. This classification expressly does not mean that mobile communications have been proven to be carcinogenic.
Newer large studies such as the COSMOS cohort study also provide no evidence that heavy mobile phone use is automatically associated with a higher risk of brain tumours. That, too, is part of a balanced assessment.
At the same time, there are gaps in knowledge
A 2025 publication by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) is particularly interesting. In it, the organisation continues to describe a need for research, including on whole-body exposure, the combination of different frequencies, thermal dosimetry, eye exposure, short, more intense exposure events and possible differences between population groups.
At the same time, ICNIRP stresses that no sufficiently plausible evidence of adverse health effects below the established thresholds could be derived from research to date. The scientifically interesting position therefore lies between two extremes:
A researcher examines high-frequency electromagnetic fields in a shielded laboratory.
There is currently no robust evidence of a general health hazard from 6G – but equally, not all long-term questions can already have been answered for a nationwide technology that does not yet exist.
What does a denser network mean?
New generations of mobile communications change more than just the frequency. Already with 5G, more networked objects, beamforming and in some cases denser transmitter structures are being used. With 6G, this development is likely to continue as vehicles, buildings, machines, sensors and possibly large parts of our environment communicate digitally with each other all the time. This does not automatically mean higher individual radiation exposure. Smaller radio cells, for example, can also work with lower power. Above all, however, it means: real exposure becomes more complex.
- How do several frequencies act at the same time?
- How relevant are short, highly directional radio pulses?
- How does total exposure change in an environment with thousands of communicating sensors?
- Are today’s measurement methods sufficient to represent dynamic beamforming realistically?
- And how well are particularly sensitive groups of people taken into account in future exposure models?
6G could connect far more devices than today’s mobile networks. What matters, therefore, is not only the output of individual transmitters but the real total exposure in an increasingly networked environment.
Research on millimetre waves
The German Federal Office for Radiation Protection (BfS) is also looking into these questions. The BfS describes centimetre and millimetre waves as less well studied than established mobile frequencies and sees a need for research on their biological effects. A study on human skin cells at 27 and 41 GHz, however, found no evidence of negative effects, even at high power flux densities.
That is a relevant result. Equally important, however, is putting it into context: a study on skin cells does not automatically answer all questions about decades of real exposure of an entire population.
Technology assessment before the roll-out
6G could bring great advantages: more efficient industrial processes, better communication in rural regions, intelligent traffic control, new medical applications and more powerful decentralised systems. But technical performance alone should not be the only yardstick.
Precisely because 6G is still under development, there is an opportunity today to ask questions about health, data protection, energy consumption, resilience and social control before the infrastructure is built, not afterwards. Responsible development of the technology would therefore have to pursue three things in parallel:
Enable innovation. Measure exposure transparently. Research open health questions independently.
Conclusion
With 6G, neither blanket fear nor blanket reassurance would be helpful. The current state of scientific knowledge provides no evidence that exposure to such radio below the applicable limits is necessarily harmful to health. At the same time, research questions remain, and for a technology that has not yet been introduced, long-term experience cannot, by its nature, yet exist. A simple, comprehensible principle should therefore apply:
The more comprehensively a technology permeates our living space, the more transparently its effects should be studied.
Progress and precaution should not in themselves be opposites. Technological freedom does not come from ignoring possible questions – but from asking them openly and scientifically, examining them and enabling people to make an informed decision.
Sources
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