Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

The skin sensitising properties of ZPS were determined in a GLP study according OECD guideline 429 (Local Lymph Node Assay (LLNA)) and EU method B.42 (Harlan CCR, 2012). For this purpose, three groups of 5 female mice each were treated with increasing concentrations of ZPS (2.5%, 5% and 10% in vehicle (w/w), respectively) applied on the dorsum of both ears (25 µL per ear) for three consecutive days. Three days after the last treatment, all animals received an intravenous injection of 3H-methyl Thymidine (3HTdR). Five hours later, the 3HTdR incorporation in the draining auricular lymph nodes was determined. The results were compared with those of a control group which was treated with the vehicle (ethanol/sterile water, 3:7 v/v). A positive control group treated with α-hexyl cinnamaldehyde (up to 25% HCA solution in acetone:olive oil, 4:1 v/v) was included in the report as a reliability check.

No signs of irritation were observed after application of a 2.5%, 5% and 10% concentration of ZPS.

Stimulation indices (SIs) of 1.14, 0.96 and 1.97 were calculated in response to a 2.5%, 5% and 10% ZPS concentration, respectively. Since the SIs were lower than 3 at all concentrations the results indicted that ZPS should not be considered a skin sensitiser (a SI of 3 is the limiting value required for classification as a skin sensitiser).

Migrated from Short description of key information:
The substance was not a skin sensitiser in a local lymph node assay in the mouse.

Justification for classification or non-classification

Based on the results of the skin sensitisation study, ZPS does not need to be classified according to Directive 67/548/EEC and according to the EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.