The epiCS® Skin Corrosion Test Method

Abstract

The epiCS® skin corrosion test method classifying chemicals either as corrosive (category 1) or non-corrosive (no category) was validated in 2009 according to OECD TG 431. Recently, the EU Classification, Labelling and Packaging Regulation (EU CLP) system required the subcategorization of corrosive chemicals into the UN GHS optional subcategories 1A and 1B and 1C. Eighty chemicals including solids, semi-solids and liquids of different chemical classes (e.g. electrophiles, organic bases and acids, neutral organics, surfactants, inorganic salts, acids, phenols), selected by the OECD expert group on skin corrosion, were tested in two independent runs. Freeze-inactivated tissues were used to correct for direct MTT reduction and interference by colouring agents. The results with the epiCS® test method demonstrate correctly classified corrosive and non-corrosive chemicals with high sensitivity (87, 50%) and specificity (71, 62%). The overall accuracy regarding subcategorization into UN GHS subcategories 1A and 1B and 1C is 69, 81% [1]. The results demonstrate that the epiCS® method is able to correctly identify corrosive and non-corrosive chemicals and can discriminate 1A and 1B and 1C chemical categories.