Implementation of an in vitro exposure system for 28 GHz

Lee

et al. 2020

IJMS

Self Cite

With the rapid growth of wireless communication devices, the influences of electromagnetic fields (EMF) on human health are gathering increasing attention. Since the skin is the largest organ of the body and is located at the outermost layer, it is considered a major target for the health effects of EMF. Skin pigmentation represents one of the most frequent symptoms caused by various non-ionizing radiations, including ultraviolet radiation, blue light, infrared, and extremely low frequency (ELF). Here, we investigated the effects of EMFs with long-term evolution (LTE, 1.762 GHz) and 5G (28 GHz) bandwidth on skin pigmentation in vitro. Murine and Human melanoma cells (B16F10 and MNT-1) were exposed to either LTE or 5G for 4 h per day, which is considered the upper bound of average smartphone use time. It was shown that neither LTE nor 5G exposure induced significant effects on cell viability or pigmentation. The dendrites of MNT-1 were neither lengthened nor regressed after EMF exposure. Skin pigmentation effects of EMFs were further examined in the human keratinocyte cell line (MNT-1-HaCaT) co-culture system, which confirmed the absence of significant hyper-pigmentation effects of LTE and 5G EMFs. Lastly, MelanoDerm™, a 3D pigmented human epidermis model, was irradiated with LTE (1.762 GHz) or 5G (28 GHz), and image analysis and special staining were performed. No changes in the brightness of MelanoDerm™ tissues were observed in LTE- or 5G-exposed tissues, except for only minimal changes in the size of melanocytes. Collectively, these results imply that exposure to LTE and 5G EMFs may not affect melanin synthesis or skin pigmentation under normal smartphone use condition.

“…The 5G exposure system for 28 GHz experiments was developed for in vitro studies [25]. The "all-in-one" system integrates every system component into a single unit.…”

Section: G Exposure Systemmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Effects of Electromagnetic Waves with LTE and 5G Bandwidth on the Skin Pigmentation In Vitro

Lee

et al. 2020

IJMS

Self Cite

“…The “all-in-one” system integrates all system components into a single unit. The exposure chamber was designed according to the previous studies to achieve field uniformity [ 20 , 21 ]. Actual uniformity inside the chamber was checked by planar measurements.…”

Section: Methodsmentioning

confidence: 99%

“…Actual uniformity inside the chamber was checked by planar measurements. Cells exposed were located at a distance of 140 mm from an antenna with an input power of 0.4 W according to the relation between the intensity and the input power inside the chamber [ 21 ]. To suppress thermal effects during exposures, especially for high power conditions, temperature was regulated through control of air-flow rates of the incubator according to the cell temperatures measured by the infrared (IR) camera via real-time feedback.…”

Section: Methodsmentioning

confidence: 99%

5G Electromagnetic Radiation Attenuates Skin Melanogenesis In Vitro by Suppressing ROS Generation

et al. 2022

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Recently, the impacts of 5G electromagnetic radiation (EMR) with 28 GHz on human health have been attracting public attention with the advent of 5G wireless communication. Here, we report that 5G (28 GHz) EMR can attenuate the skin pigmentation in murine melanoma cells (B16F10) and a 3D pigmented human epidermis model (Melanoderm™). B16 cells were exposed to 5G (28 GHz) with or without α-MSH for 4 h per day. Interestingly, 5G attenuated α-MSH-induced melanin synthesis. Fontana–Masson staining confirmed that the dendritic formation of α-MSH stimulated B16 cells was diminished by 5G exposure. To confirm the anti-melanogenic effect of 5G EMR, MelanoDerm™ was irradiated with 5G at a power intensity of 10 W/m2 for 4 h a day for 16 days and melanin distribution was detected with Fontana–Masson staining, which supported the anti-melanogenic effect of 5G EMR. Consistently, 5G EMR suppressed α-MSH induced upregulation of melanogenic enzymes; tyrosinase, TRP-1, and TRP-2. Of note, 5G EMR attenuated ROS production stimulated by α-MSH and H2O2, suggesting that 5G EMR may dissipate ROS generation, which is pivotal for the melanin synthesis. Collectively, we demonstrated that 5G EMR can attenuate skin pigmentation by attenuating ROS generation.

“…Therefore, it is essential to develop an in vitro experimental system for 5G exposures to investigate biological and health effects caused by 5G electromagnetic field (EMF). Thus, an in vitro experimental system for 28 GHz, specified in the 3GPP standard as FR2 [2], has been developed in this context [3], [4]. A skin pigmentation effect caused by 28 GHz exposures has also been reported [5].…”

Section: Introductionmentioning

confidence: 99%

An In Vitro Experimental System for 5G 3.5 GHz Exposures

et al. 2022

Self Cite

In this study, an in vitro experimental system is developed for fifth-generation (5G) 3.5 GHz exposures. A radial transmission line (RTL) housed in an incubator can support the single-mode propagation at a 3.5 GHz band. A conical antenna is also placed at the center of an RTL to ensure field symmetries. A 5G signal generator along with a customized power amplifier can create 5G new radio time division duplex (TDD) waveforms. Additionally, a feedback scheme implemented by employing a directional coupler and power meter allows power control to ensure a steady output power. The system is evaluated based on temperature measurements using the initial temperature slope and nonlinear curve fitting to determine the specific absorption rate (SAR) values. Comparing SARs obtained from a "worst-case" signal of a maximum power condition with the values obtained from a "TDD" signal of an actual 5G TDD transmission gives the initial slope ratio of 0.741, which is very similar to the theoretical duty cycle of 0.743. It is also shown that the average output power, water temperature, incubator air temperature, and CO 2 density are adequately controlled for appropriate in vitro experiments.