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Description of key information

Two in vitro studies were set up: a DPRA and a KeratinoSens study. During the preliminary studies proceeding the main in vitro test, it was however found that the test item, L-tyrosine, is insufficiently soluble in any of the solvents applicable for these two tests at the required concentration level. Consequently, the main tests could not be performed.

Key value for chemical safety assessment

Justification for classification or non-classification

Due to the technical limitations occuring in the DPRA and the KeratinoSens study, in vitro skin sens testing was not possible.

L-tyrosine is an essential amino acid and the precursor to the natural skin pigment melanin. As such, tyrosine is ubiquitously present in (and on) the human skin, and is not expected to exert skin sensitizing effects. Based on this information, and for reasons of animal welfare, additional in vivo testing of the skin sensitizing properties of L-tyrosine is not deemed necessary.