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Updated: Sep 28, 2025

An In Vitro Skin Irritation Test SIT using the EpiDerm Reconstructed Human Epidermal RHE Model
Published on: July 13, 2009
Effects of skin washing frequency on the epidermal barrier function and inflammatory processes of the epidermis: An
Cara Symanzik1,2, Sanja Kezic3, Ivone Jakasa4
1Department of Dermatology, Environmental Medicine and Health Theory, Osnabrück University, Osnabrück, Germany.
Background:
Increased hand hygiene measures during the COVID-19 pandemic have led to an increased quantum of hand eczema (HE).
Objectives:
To examine the effects of varying washing frequencies using current mild cleansing agents-alongside with the effect of a rehydrating cream-on the epidermal barrier function and inflammatory processes of the stratum corneum(SC).
Methods:
Standardized skin washings on the volar aspects of the lower arms of skin-healthy volunteers were performed using the automated cleansing device either 5 or 11 times within 4 h for 60 s each with a standard cleanser, a lipid-containing syndet, or a lipid-containing syndet followed by one-time application of a rehydrating cream. Skin bioengineering parameters (transepidermal water loss, SC hydration, erythema, and SC pH) and biochemical/immunological parameters (interleukin-1α, interleukin-1α receptor antagonist and natural moisturizing factor) of SCsamples collected by tape stripping were assessed.
Results:
All applied washing procedures provided comparable, mild effects on the epidermal barrier function and skin inflammation.
Conclusion:
Occupational skin cleansers seem to have improved regarding skin barrier damaging effects. To further corroborate this, a study design, modified on the basis of our findings, applying longer washing periods for consecutive days seems desirable.
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