Is Nicomenthyl 20 eye irritating?

No. As demonstrated by validated in vitro testing, Nicomenthyl 20 is not irritant for the eyes. However, for the precautionary principle (cfr. https://en.wikipedia.org/wiki/Precautionary_principle) , it is classified as Eye Irritant 2 H319 (causes serious eye irritation) according to Regulation 1272/2008/EC (CLP).