# WEB-033 — 60 GHz: skin-model injury thresholds and the limits of averaging

Why this matters
A small damaged area can disappear inside an average taken across a whole sample. This report found that inspecting the exposed tissue revealed local injury that a bulk viability reading could miss. It also investigated how hot, humid surroundings changed the injury threshold.

Id: WEB-033

Author: Ikehata et al.

Full Authors: Masateru Ikehata; Sachiko Yoshie; Yukihisa Suzuki; Hiroshi Sasaki

Year: 2026

Title: Evaluation of Cytotoxicity Threshold Induced by Thermal Effects of Millimeter-wave Electromagnetic Fields

Journal: Quarterly Report of RTRI

Citation: Masateru Ikehata; Sachiko Yoshie; Yukihisa Suzuki; Hiroshi Sasaki. Evaluation of Cytotoxicity Threshold Induced by Thermal Effects of Millimeter-wave Electromagnetic Fields. Quarterly Report of RTRI. 2026. doi:10.2219/rtriqr.67.2_81.

Doi: 10.2219/rtriqr.67.2_81

Topic: Millimetre-wave thermal thresholds; Environmental modification of injury thresholds; 60 GHz-region biological responses

Verification Group: Original text reviewed

Record Role: Original text reviewed

Featured: False

Exposure: 60 GHz for 6 min; reconstructed tissue models at 33°C/50% RH or 42.5°C/80% RH.

Design: Human-cell three-dimensional skin/corneal models; focused exposure, temperature monitoring and image-based MTT viability assessment.

Finding: Skin-model damage threshold: 180–250 mW/cm² in standard conditions, 130–150 mW/cm² in hot/humid conditions. Local injury could be obscured by whole-sample absorbance.

Statistics: See the original results; effect sizes were not independently recalculated.

Boundary: Institutional original technical report. Deliberate thermal-injury experiment; damage appeared near surface temperatures above 50°C. Thresholds do not describe ordinary communications exposure.

Related: Companion Japanese programme to the 2024 rabbit-eye study; different biological model. Related publication records: WEB-032.

Protection Question: Which exposure conditions reproduce this finding, and what would establish its relevance beyond the experimental model?

Access: Original methods/results and interpretation reviewed; raw data and supplements were not independently audited.

Locator: Original methods and results

Notice: Linked Europe PMC/PubMed notice fields checked 21 October 2026; no correction/retraction surfaced for this record. Publisher/citation screening is not exhaustive.

Funding: Commissioned by Japan’s Ministry of Internal Affairs and Communications.

Conflicts: See original disclosure; no independently verified conflict assessment.

Source Url: https://doi.org/10.2219/rtriqr.67.2_81

Retrieval Links: https://doi.org/10.2219/rtriqr.67.2_81 | https://www.jstage.jst.go.jp/article/rtriqr/67/2/67_rtriqr.67.2_81/_html/-char/en

Verification Date: 2026-10-21

Discovery Id: TARGETED-20261021-06

Technology Tracks: wigig|millimetre

Technology Connection: 60 GHz-region or adjacent-band biology; not an experiment with a WiGig device and not evidence of an oxygen-deprivation mechanism.

Publication Type: Original institutional technical report

Study Setting: Cells / isolated tissue

Browse Categories: cells