Buy Vegan USP 51 Preservative Efficacy Test (PET) - Cosmetic challenge test

This Vegan friendly edition of United States Pharmacopeia (USP) test is most commonly used for products sold in the United States but is recognised worldwide.

The United States Pharmacopeia (USP) differs to the traditional European Pharmacopoeia method with the addition of an extra microorganism culture, E. coli. During this antimicrobial effectiveness test, the testing is conducted at 7, 14 and 28 days compared to the traditional European Pharmacopoeia (EP) method where testing is conducted at 2, 7, 14 and 28-days. This does make the USP test method less stringent but if you are planning on selling your product within the United States of America this is the minimum required test.