Chapter 46 – Skin Penetration

The cosmetic industry continues to expand worldwide. The claims described on a cosmetic product label or in promotional material must be substantiated with scientific data or clinical studies, ensuring that the product actually has the promised effect. Cosmetics must be safe to use over a long term, so safety assurance is critical. Testing the skin penetration of cosmetic actives and excipients is one example of the safety measures that are required. With the prohibition of animal testing for cosmetic evaluation in Europe, product safety has had to be assessed by in vitro methods or in vivo human studies. This has led to a new set of challenges to find and validate in vitro techniques that reliably predict in vivo human responses.