ASSESSMENT OF THE IN-HOUSE PERFORMANCE OF THE EPIDERM™ AND EPISKIN™ IN VITRO CORROSIVITY TESTS.

The purpose of this study, conducted by scientists at Unilever’s Safety and Environmental Assurance Centre, was to assess the in-house performance of the EpiDerm and EPISKIN corrosivity tests using materials of known corrosive potential (six corrosives and six non-corrosives), as recommended in the draft OECD test guideline (TG) 431. Determination of the labelling requirements for certain products and ingredients under the Dangerous Substances Directive requires information on their skin corrosivity potential. This information may now be obtained by using an in vitro skin corrosivity test, of which there are two validated commercial tests available, the in vitro EpiDerm and EPISKIN corrosivity tests. These tests are designed to predict and classify the skin corrosivity potential of a test material by assessing its effect on a reconstituted 3-dimensional (3-D) human skin model, and are based on the fact that corrosive chemicals show cytotoxic effects following short-term application to the epidermal stratum corneum. Both the EpiDerm and EPISKIN tests distinguish between corrosives and non-corrosives, but the prediction model for the EPISKIN test also assigns EU risk phrases or UN packing groups to corrosive materials. However, as stated in the Discussion and Conclusions section of this paper, “the identification of corrosive labelling/packing groups by the EPISKIN test in this study was not reliable; much larger numbers of corrosive chemicals would need to be tested to assess the in-house use of EPISKIN for assigning corrosive class correctly.” STUDY CONCLUSION: “OVERALL, THERE WERE NO DIFFERENCES BETWEEN THE TWO TESTS IN TERMS OF PREDICTIVE ABILITY IN THIS STUDY.”

3-dimensional (3-D) human skin model, Corrosion, Corrosive potential, Corrosivity, Corrosivity Tests, Dermal corrosion, Dermal corrosivity, EPISKIN, EpiDerm, OECD, OECD test guideline, Prediction model, Skin corrosivity, Stratum corneum, TG 431