P42 Characterizing skin barrier damage associated with surfactant and ethanol exposure: Insights from a porcine explant model

Introduction and aims Hand cleansing is a common hygiene practice to reduce the spread of infectious disease. However, frequent use of surfactant cleansers and ethanol sanitizers, can result in dermatitis. This work aimed to understand how skin exposure to sodium dodecyl sulfate (SDS) and ethanol damages the skin and compromises skin barrier function. Methods Porcine underbelly skin was exposed for 1 h to SDS solutions (0.1–10%), or 85% ethanol, with or without rinsing. Changes in skin wettability was determined from the contact angle of water on the treated skin. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra of the outer layers of skin exposed to deuterated SDS or ethanol were collected by placing the treated skin on an ATR crystal. To collect spectra as a function of skin depth sequential layers of stratum corneum (SC) were removed by tape stripping. Results Contact angle measurements of water on skin demonstrated a dose-dependent decrease after SDS exposure, indicating a more hydrophilic surface; this was partially recovered for lower SDS concentrations by rinsing with water. In contrast, ethanol exposure increased the contact angle of water on skin, indicating the skin surface was more hydrophobic. ATR-FTIR spectra of tape-stripped skin showed a dose-dependent SDS penetration, which was not removed by rinsing. Ethanol also penetrated the SC but to a lesser extent. Conclusions Skin exposure to both SDS and ethanol alter the surface properties (wettability) of stratum corneum, which will affect the spreading and permeation of exogenous materials. Both SDS and ethanol penetrated several microns into the SC. In future work, the porcine model developed in these studies will be extended to assess the accumulative effects of chronic cleansing and methods applied to human explant and organoid models to test genetic effects on barrier resilience.