Ashland Shanghai Technical lab modified traditional corneosurfametry and used in both in-vivo and in-vitro methods to evaluate the influence of difference preservatives in shampoo. The results showed that the water solubility could be a key influence factor in rinse-off products. Lipophilic preservatives could deposit more on skin/scalp and cause potential irritation. This new developed method combined both clinical studies and instrumental measurement and could be used as a fast screening for the safety of preservatives in rinse-off products.