A new GOLIAT study led by researchers from INERIS reports no measurable biological effects of short-term exposure to 5G signals on either stress responses or brain electrical activity in healthy adults. The results of the study were disclosed in two different papers published in Environmental Research. These are the first coordinated human laboratory studies to assess potential acute effects of exposure to the highest frequency band of 5G under conditions that resemble real environmental levels.
Both studies examined exposure to real 5G signals and found no changes in physiological stress markersor in the patterns of electrical activity that the brain naturally generates at rest. The results indicate that brief exposure to 5G signals similar to those found in the environment did not alter the body’s stress response or the brain’s typical electrical rhythms.
Methodology
The studies shared a triple-blind, randomized design, in which participants, experimenters and data analysts did not know whether a real or sham (placebo) exposure was being administered. All sessions took place in an electromagnetically shielded room to avoid interference. Participants —31 in total— were seated 120 cm from a horn antenna emitting a 5G New Radio signal at 26 GHz, with intensities of 2 V/m at the head and 1 V/m at the torso—levels corresponding to the highest values measured in real outdoor environments by the French national frequency authority.
Both studies were carried out at the same time with the same protocol: each volunteer completed one session with real exposure and one with sham exposure, each lasting around one hour, including 26.5 minutes of exposure. During these sessions, researchers collected saliva samples from 16 participants to analyse two validated stress biomarkers (cortisol and alpha-amylase) and recorded the brain’s electrical activity using electroencephalography. This approach allowed the team to assess both physiological stress responses and potential changes in the brain’s natural electrical patterns under identical exposure conditions.
No changes detected in brain electrical activity
Using electroencephalography, the researchers monitored the brain’s electrical oscillations across all major frequency bands—delta, theta, alpha and beta—which correspond to different natural rhythms of brain activity. These range from the slow waves linked to deep rest (delta) to the faster waves associated with alertness and mental activity (beta). Across all bands, and at all time points before, during and after exposure, the researchers found no differences between the real and sham exposure sessions.
Short-term exposure also did not affect the body’s physiological stress response. Cortisol and alpha-amylase, two widely used indicators of stress and autonomic nervous system activation, remained stable across all sampling points. Therefore, the researchers did not find evidence that exposure to 5G signals at environmental levels triggers acute biological changes related to stress.
Why study 26 GHz?
The 5G technology uses different frequency bands. Although the 3.5 GHz had an earlier and wider deployment, the study focuses on the 26 GHz band, which is being introduced to support faster data transmission. “We focused on 26 GHz because there were very few studies examining its potential impact on humans,” explains Lisa Michelant, researcher at INERIS and first author of both papers. “It is a new frequency for public mobile communication, and its physical behaviour—such as limited penetration into the skin—differs from that of lower-frequency 4G or 5G signals”.
According to Brahim Selmaoui, researcher at INERIS and senior author of the research: “These findings are consistent with previous scientific evidence showing no acute biological effects at commonly encountered radiofrequency exposure levels. While more research is still needed on long-term and repeated exposures, our results provide reassuring data for this new 5G band and contribute to ongoing safety assessments by international health authorities.”
This research is part of Project GOLIAT, a five year project funded by European Union’s Horizon Europe research and Innovation programme under Grant Agreement No 101057262. The project is coordinated by the Barcelona Institute for Global Health (ISGlobal).
Michelant L, Baz T, Carrie A, Hugueville L, Lévêque P, Selmaoui B. Millimeter-wave high frequency 5G (26 GHz) electromagnetic fields do not modulate human brain electrical activity. Environ Res. 2025 Nov 18:123349. doi: 10.1016/j.envres.2025.123349. Epub ahead of print. PMID: 41265672.
Michelant L, Hugueville L, Lévêque P, Selmaoui B. No measurable impact of acute 26 GHz 5G exposure on salivary stress markers in healthy adults. Environ Res. 2025 Nov 27;290:123439. doi: 10.1016/j.envres.2025.123439. Epub ahead of print. PMID: 41317834.
As digital infrastructures expand rapidly, questions are emerging about their interaction with living systems. A new study from the ETAIN Project takes a closer look at what happens when insects are exposed to radiofrequency electromagnetic fields (RF-EMF) associated with 5G technologies.
The research focuses on insects as key ecological indicators, given their essential role in pollination, food systems, and ecosystem stability. Using controlled laboratory conditions, the study examines behavioural and physiological responses of insects when exposed to RF-EMF within ranges relevant to current and emerging mobile communication networks.
Rather than drawing premature conclusions, the study emphasises careful experimental design, reproducibility, and transparent exposure assessment. This approach helps address existing gaps in scientific knowledge, where results have often been inconsistent due to methodological differences. By refining protocols and measurement techniques, ETAIN contributes to improving the quality and comparability of research in this field.
Beyond the laboratory, the study is framed within a broader planetary health perspective. It highlights the need to assess technological innovation not only in terms of performance and efficiency, but also through its potential environmental and ecological effects. Insects, as highly sensitive and widely distributed organisms, offer valuable insights into these interactions.
This work represents an important step in ETAIN’s wider mission: supporting evidence-based dialogue on digitalisation, environmental sustainability, and health. By strengthening the scientific basis for assessment, the project aims to inform policymakers, researchers, and society at large as decisions about future connectivity are made.
From 23–27 September 2025, the ETAIN Project participated in the 49th Apimondia Conference, the world’s largest global event dedicated to beekeeping, pollinator science, and apicultural innovation. With over 8,200 participants from across the world, Apimondia 2025 provided a unique international forum to exchange knowledge on the challenges facing insects and pollinators.
ETAIN contributed to the scientific programme by presenting three research posters exploring the potential effects of radiofrequency electromagnetic fields (RF-EMF) on insects and pollinators. The presentations reflected the project’s interdisciplinary approach, combining experimental studies, exposure assessment, and planetary health perspectives to better understand how emerging digital infrastructures may interact with biological systems.
One poster focused on laboratory and field-based observations of pollinator behaviour and physiology under RF-EMF exposure. A second addressed methodological advances in exposure assessment and modelling, while a third explored how citizen science and digital tools can support large-scale data collection on environmental exposure. Together, these contributions highlighted the importance of robust, transparent methodologies and cross-sector collaboration when investigating environmental health risks.
By engaging with beekeepers, scientists, policymakers, and industry representatives, ETAIN reinforced the relevance of its work beyond academia. Participation in Apimondia strengthened dialogue between research and practice, helping to translate scientific evidence into shared understanding and informed decision-making for pollinator protection in an increasingly connected world.
A study from #ProjectGOLIAT shows that environmental exposure to radiofrequency electromagnetic fields (RF-EMF) in Europe remains below international safety limits but varies by urbanicity, network quality and how the phone is used
A new study led by researchers from the Swiss TPH under the umbrella of Project GOLIAT provides the most comprehensive assessment up to date of environmental and personal exposure to radiofrequency electromagnetic fields (RF-EMF) from 5G networks across ten European countries. The results have been published in Environment International.
The study assessed exposure levels in over 800 different microenvironments — including schools, transport hubs, and residential areas — in both urban and rural settings across Austria, Belgium, France, Hungary, Italy, the Netherlands, Poland, Spain, Switzerland, and the UK.
Using backpack-mounted RF exposimeters and mobile phones configured for different usage scenarios (non-use, maximum download, and maximum upload), researchers measured exposure across 35 frequency bands, including key 5G frequencies like 3.5 GHz. Measurements were taken between 2023 and 2024 under real-world conditions.
Environmental levels well below the limits
The first of the scenarios assessed was the non-user mode, in which the researchers’ phones were set in flight mode. With this method, the team assessed environmental exposure to RF-EMF, which in line with previous research, was found to be generally low and remained well below international guidelines.
“We observed that in the non-use scenario exposure was lower in rural areas and tended to increase with urbanisation, something that can be attributed to a higher density of base stations in urban areas”, says Adriana Fernandes Veludo, first author of the study.
The lowest environmental levels of exposure were registered in those countries with more stringent precautionary levels of RF-EMF, such as Switzerland, Belgium or Italy.
Higher levels when mobile phones are actively used
The data revealed that exposure to RF-EMF increased substantially when mobile phones were actively used. In the scenario where mobile phones were set to download large files, exposure was -depending on the country- from 2 to to 20 times higher than in the non-use scenario, due to emissions from the phone interacting with the base station. Interestingly, the new 5G bands have been used only in some countries, reflecting country differences in the state of 5G implementation.
Lastly, the highest levels of exposure were registered in the maximum uplink scenario, where phones were set to upload large amounts of data and emitted about 30 cm away from the measurement device. Compared to the non-use scenario, exposure levels were between 9 and 53 times higher, depending on the country. Those with the highest mean levels of exposure were the Netherlands, Italy and Belgium.
“Unlike in the non-use scenario, in the maximum data upload scenario the highest exposure levels were measured in rural areas, where the network signal quality is poorer and the phones need to emit at higher power to send the data”, says Martin Röösli, researcher at the Swiss TPH and last author of the study.
It is important to note that in the Netherlands and in Poland 5G services in the 3.5 GHz frequency band were not yet in use at the time of the measurements, in 2023, and have only been launched in 2024. In 2025, the teams are busy collecting new data and it will be possible to evaluate the evolution of 5G exposure levels in Europe, with particular interest in these two countries that now have 5G services available.
Reference Adriana Fernandes Veludo, Bram Stroobandt, Han Van Bladel, Nekane Sandoval-Diez, Kenneth Deprez, Sam Aerts, Wassim Ben Chikha, Joe Wiart, Zsuzsanna Vecsei, Péter Pál Necz, György Thuróczy, Martina Benini, Marta Bonato, Silvia Gallucci, Gabriella Tognola, Marta Parazzini, Lea Beláčková, Nina Vaupotič, Pawel Mamrot, Magda Marianska, Piotr Politanski, Kinga Polanska, Matthew Stamets, Patricia de Llobet, Gemma Castaño-Vinyals, Mònica Guxens, Paige M. Hulls, Frank de Vocht, Wout Joseph, Martin Röösli, Assessing radiofrequency electromagnetic field exposure in multiple microenvironments across ten European countries with a focus on 5G, Environment International, Volume 200, 2025, 109540, ISSN 0160-4120, https://doi.org/10.1016/j.envint.2025.109540.
Proudly representing CLUE-H at the 4th Annual Meeting at BioEM 2025
CLUE-H 4th Annual Meeting at BioEM 2025
The 4th Annual Meeting of the European Cluster of EMF and Health (CLUE-H) took place on 25 June 2025 during BioEM 2025 in Rennes, France, at the historic Couvent des Jacobins. This annual event brought together key stakeholders from academia, industry, and policy to review progress, address challenges, and plan future directions in EMF and health research. Remote access enabled broader participation, ensuring that researchers from across Europe could join the discussions.
Like last year, the meeting featured updates from the cluster projects—NextGEM, SEAWave, GOLIAT, and ETAIN—which together aim to fill knowledge gaps regarding the impact of wireless technologies on health and the environment. The agenda included dedicated sessions on communication, data management, experimental studies, exposure assessment, and policy development, with project coordinators and working group leaders presenting the latest findings.
At the special CLUE-H cluster session, Anke Huss, ETAIN project coordinator from Utrecht University, shared the latest project developments. The session offered a valuable opportunity to exchange insights, align methodologies, and deepen collaboration, particularly on experimental studies and exposure assessment. Over 40 participants attended, reflecting the shared commitment across projects to advancing EMF and health research.
For readers interested in more detailed information, updates about the BioEM meeting can also be found on the ETAIN website and the NextGEM website.
Next steps and follow-up:
Continued dissemination of policy briefs and scientific findings.
Further harmonisation of experimental protocols and data management practices across projects.
