The ever-increasing use of wireless communication systems during the last few decades has raised concerns about the potential health effects of electromagnetic fields (EMFs) on humans. Safety limits and exposure assessment methods were developed and are regularly updated to mitigate health risks. Continuous radiofrequency EMF monitoring networks and in situ measurement campaigns provide useful information about environmental EMF levels and their variations over time and in different microenvironments. In this study, published data from the five largest monitoring networks and from two extensive in situ measurement campaigns in different European countries were gathered and processed. Median electric field values for monitoring networks across different countries lay in the interval of 0.67–1.51 V/m. The median electric field value across different microenvironments, as evaluated from in situ measurements, varied from 0.10 V/m to 1.42 V/m. The differences between networks were identified and mainly attributed to variations in population density. No significant trends in the temporal evolution of EMF levels were observed. The influences of parameters such as population density, type of microenvironment, and height of measurement on EMF levels were investigated.

The introduction of 5G networks has raised public concerns about potential changes in environmental electromagnetic field (EMF) exposure. This study analyzes continuous monitoring data collected over 2 years (August 2022–October 2024) from 13 frequency‐selective monitoring sensors located in Greece's five largest cities. Focusing on the 3.6 GHz band, we evaluated trends and weekly variations in EMF levels. Results indicated a gradual increase in EMF exposure at 3.6 GHz, driven by the growing penetration of 5G infrastructure and devices. Notably, this band exhibited higher maximum‐to‐median power density ratios compared to other frequency bands, attributable to active antenna systems' characteristics and traffic variations. Applying the ICNIRP 2020 guidelines, we found that 30‐min averaged values significantly reduced these variations. All measured EMF levels, including maximum values, remained well below Greek and international safety limits. These findings, especially the increasing trend identified for the EMF levels, underscore the importance of continuous monitoring networks for assessing EMF exposure to existing and emerging telecommunications networks and ensuring compliance with safety standards.

The upper part of the frequency spectrum (millimeter waves, MMW) applied by modern communications technologies (5G and beyond), makes skin the dominantly exposed tissue to electromagnetic fields. In this work, a methodology for murine skin dosimetry evaluation is presented, intended to contribute to animal studies with mice exposed to MMW radiation, in particular 27.5 GHz. A stratified skin model is proposed and the variations of the skin layers’ thicknesses during a hair cycle are measured in mice. The variations of skin layers’ dielectric properties due to age, based on the changes of total body water, are also evaluated. The impact of these variations in dosimetric metrics (i.e., mean absorbed power density, APD, and power loss) within each layer is assessed and found to be significant. Changes in the skin layers’ thicknesses throughout a hair cycle considerably affect the APD, resulting in a two-fold increase, compared to changes in the dielectric properties due to aging or due to hair presence inside the skin.

Millimeter wave (MMW) technology is increasingly used in telecommunications and medical applications, necessitating a deeper understanding of its interaction with human tissue, particularly skin. The limited penetration depth of MMWs makes the skin the primary site of energy absorption, requiring detailed dosimetric analysis. Traditional skin models often assume planar, layered structures, neglecting the natural undulating geometry of the epidermis and dermis. This study introduces a novel methodological framework for constructing realistic three-dimensional (3D) human skin models using Optical Coherence Tomography (OCT) and Ultrasound (US) imaging. The framework involves three key steps: (1) OCT and US image acquisition, (2) image segmentation and processing, and (3) synthesis of processed data to generate high-fidelity 3D skin models. Three anatomical sites—the volar forearm, hypothenar region, and fingertip—were selected for model development, representing variations in skin roughness and layer composition. The dielectric properties of the skin and subcutaneous layers were incorporated into finite-difference time-domain (FDTD) simulations at 27.5 GHz to evaluate the impact of skin roughness on electromagnetic field distribution. Our results demonstrate that the natural undulations of the dermoepidermal junction and air-skin interface significantly affect MMW energy absorption patterns. The roughness of these interfaces varies across anatomical sites, influencing local electric field distributions and leading to deviations from predictions based on planar models. The findings suggest that incorporating realistic skin geometries enhances dosimetric accuracy, which is critical for both safety assessments and optimizing MMW-based medical applications. This study provides an approach for individualized MMW dosimetry and underscores the importance of considering anatomical variations in electromagnetic exposure assessments. The framework was additionally extended to a nodular basal cell carcinoma case, revealing marginal changes in local field and SAR distributions and a moderate increase in reflected power compared to healthy skin.