Effects of various grit-containing cleansers on skin barrier function

Products intended for individuals in contact with strongly adhering dirt of ten contain grit. Various clinical test methods have been developed for eva luating the potential of personal washing products to induce skin irritatio n. In the present study, differences in the irritant effects of washing pro ducts containing naturally-derived grit and synthetic grit were investigate d in a forearm wash test. The forearms of 16 test subjects were washed in a total of 18 treatments (4 per day for 4 days, with 2 treatments on the 5th day). Treatment consisted of continuous washing for 2 min by a technician, who gently slid his fingertips with the lather up and down the forearm. No n-invasive instrumental measurements of skin barrier function were performe d. Repetitive washing for 1 week lead to increased TEWL values, skin rednes s and decreased stratum corneum hydration. Results indicate differences in irritancy potential due to different types of grit, their surface and conce ntration. It is concluded that the repeated wash test seems to be adequate for rating personal washing products that contain grit.