Effects of skin washing frequency on the epidermal barrier function and inflammatory processes of the epidermis: An experimental study

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. Highlights Standardized skin washings were performed using the automated cleansing device. Skin bioengineering parameters (transepidermal water loss, stratum corneum hydration, erythema, and stratum corneum pH) and biochemical/immunological parameters (interleukin‐1α, interleukin‐1α receptor antagonist and natural moisturizing factor) were assessed. Applied washing procedures provided comparable, mild effects on the epidermal barrier function and skin inflammation.