2016 Volume 10 Issue 5 Pages 562-568
A 34-year-old female had developed an infiltrative erythematous rash on her face the morning after applying a cosmetic‘Sauna Mask'for an hour, which was composed of inner, middle, and outer layers. Patch tests produced positive findings for the mask and the middle layer, which was made of chloroprene rubber. The patient's skin rash disappeared soon after conventional treatment ; however, it frequently recurred when she perspired after playing sports or bathing. Among the substances detected by gas chromatography/mass spectrometry-based analysis of the chloroform-methanol extract of the mask, diethylthiourea, which is used as a vulcanization accelerator in chloroprene rubber, was the only agent that produced a positive result in a patch test. Furthermore, ethyl isothiocyanate, a degradation product of diethylthiourea that is produced on the skin surface at 37℃, also showed a positive result. Since ethyl isothiocyanate and diethylthiourea are reported to be extreme and non-sensitizers, respectively, we assumed that our patient had been sensitized by ethyl isothiocyanate, and thus, her contact allergy occurred after she was exposed to the diethylthiourea in the middle layer of the mask.
