A European interlaboratory evaluation study of an in vitro ocular irritation model (Skin 2TM Model ZK1100) using 15 chemicals and 3 shampoos

By Pirovano, R. - Zaninelli, P. - Noben, J. - Logemann, P. - Southee, J. - Joller, P. - Coquette, A.

The aim of this interlaboratory study was to ascertain the feasibility of the use of the in vitro Skin Model ZK1100 kit as a tissue substrate for cytotoxicity studies. Eighteen compounds - 15 raw chemicals and 3 finished products (commercial shampoos) - were tested in four different laboratories on two separate occasions, and the data obtained were compared with the data available in the literature on eye irritancy potential. The kit was easy to manage, and no technical difficulties were encountered in the estimation of MTT reduction, LDH and PGE2 release in the medium. Similar MTT50 values were recorded in two independent experiments in each laboratory, and the rankings of irritation potency within the same chemical class were comparable. Both LDH and PGE2 were important parameters to be taken into account along with MTT50 values in establishing the irritation potential of some categories of compounds.