Patch Test

 

The "Patch Test" is designed to know the response that a substance can induce when applied to a person. Given that this response depends on each individual according on their immunological predisposition (allergy, hypersensitivity, ...) for certain responses, we do not perform it, since the response obtained in some volunteers cannot be extrapolated to other individuals who are exposed to the tested substance, so we could give wrong information if when testing the product does not cause any reaction, and then when applied to other individuals, it causes some kind of reaction.

The only tests we perform to know the ability of a product to induce a response are those that do not depend on the immune system of each individual, but on the ability of the product to cause irritation, depending on the chemical nature of the product. These tests are 1) HET-CAM mucosal irritation test (Hen's Egg-Chorioallatoic Membrane), performed on chick embryo chorioallantoic membrane, an alternative test to the mucosal irritation test on the ocular mucosa of rabbits, since some years ago it has been forbidden to use experimental animals for tests with cosmetic products, and 2) Skin sensitization test, carried out through the in vitro cutaneous hypersensitivity test, with the h-CLAT method (human Cell-Line Activation Test), based on the OECD 442E: 2016 standard; 3) 3T3 NRU in vitro phototoxicity test, based on OECD 432: 2004; and 4) In vitro cytotoxicity tests, according to the UNE-EN ISO 10993-5: 2009 standard.