Authors: Djuari, M. A.; Gaide, O.; Mancuso, M.; Merla, C.; Pich-Bavastro, C.; Pinto, R.; Su, Z.; Ziemann, C.; Bitsch, A.
EUROTOX 2026: 60th Congress of the European Societies of Toxicology, 2026, Vienna, Austria, September 13–16, OS01-03, doi: https://doi.org/10.1016/j.toxlet.2026.112084
Abstract
The fifth generation of mobile phone technology (5G New Radio), first deployed in 2020, uses not only sub-6 GHz bands (FR1), but also millimeter wave frequencies (mmWave) between 24.25 and 52 GHz (FR2), enabling high-speed, low latency data communication. While the health effects of FR1 are well studied, data on FR2 remain limited. The European Horizon-funded SEAWave project aimed to comprehensively analyze the health effects of 5G FR2 from three perspectives: (i) in vitro, using primary human epidermal keratinocytes and melanocytes, (ii) in vivo, using cancer-prone (Car-S) and Ptch+/- mice models, and (iii) a human clinical study. These models were exposed to 5G FR2 at 27.5 GHz with power density between 3.33 and 20 W/m2 for 4 or 24 h, for up to 6 months, or for 20 min, respectively.
Various endpoints were investigated, focused on identifying potential early biomarkers of tumor development, alterations in the immune system, and signs of oxidative stress (OS). OS has been discussed as a potential adverse effect associated with electromagnetic field exposure. Gene expression changes were examined in all in vitro and in vivo models, along with assessment of genotoxicity, including detection of oxidative DNA damage and epigenetic alterations in vitro and histopathological changes in vivo.
Across all models, no OS-driven effects in gene expression were found. Likewise, no adverse genotoxic and epigenetic effects as well as histopathological effects were detected. However, gene expression analyses indicated that in vivo early-life FR2 exposure might be associated with potential activating effects on the nociceptor-mast cell axis and type 2 inflammatory response, independent of genotype and sex.
In the clinical study, a weak, non-significant increase in the expression of inflammatory factors was noted after 20 min of exposure. Consistently, very weak, non-significant effects were observed in juvenile keratinocytes in vitro, where some pathways were predicted to be modulated after short-term exposure.
In contrast, prolonged exposure in vivo did not alter gene expression, suggesting an adaptive reduction of the initial acute inflammatory response. In conclusion, early-life skin models appeared to be the most sensitive test systems, and slight induction of inflammatory pathways cannot be completely ruled out. However, no conclusive evidence for skin cancer development was found. Some observations require further investigation to clarify their significance, resolve inconsistencies, and assess dose dependency.