Skin roughness is negatively correlated to irritation with DMSO, but not with NaOH and SLS

While many endogenous and exogenous factors have been found to influence skin irritant reactivity, the role of skin roughness in irritation has not yet been studied. In this study we measured skin roughness by visiometry and performed irritation tests on the flexural side of the forearm with sodium hydroxide (NaOH), sodium lauryl sulphate (SLS) and dimethyl sulfoxide (DMSO) in two different concentrations in a population of 151 volunteers between 15 and 25 years of age. The results showed a significant negative correlation between most roughness parameters and DMSO irritation. The correlation between roughness parameters and irritation tests with SLS and NaOH was not significant. We conclude that smoother skin is more prone to DMSO irritation than rougher skin and that this may be due to differences in percutaneous penetration of the compound.