 EpiDerm from Mattek and EpiSkin and SkinEthic RHE model are derived from human skin cells which have been cultured to produce a model of human skin.These methods are currently accepted replacements in Canada and the European Union (EU).In August 2010, the Organisation for Economic Co-operation and Development (OECD) published the Test Guideline 439 which describes the new procedure for "in vitro" hazard identification of irritant chemicals.