This guideline provides an easy-to-understand explanation of the animal alternative test (Skin Absorption: in vitro Method) for cosmetics. 

The Skin Absorption：in vitro Method is a test method that provides information on the absorption of a test substance into a skin product. This test method can use human skin or the skin of other animal species, can be repeatedly measured for the test substance, and has a wide range of test substances that can be used, although it is not applicable to all situations. In addition, it has the advantage of being free from the limitations and ethical aspects of in vivo testing because the test can be done without using live test animals.