Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (sensitising)
Additional information:

Introduction.  A study was performed to assess the skin sensitisation potential of the test item in the CBA/Ca strain mouse following topical application to the dorsal surface of the ear. The method was designed to be compatible with the following: OECD Guideline for the Testing of Chemicals No. 429 "Skin Sensitisation: Local Lymph Node Assay" (adopted 22 July 2010) Method B42 Skin Sensitisation (Local Lymph Node Assay) of Commission Regulation (EC) No. 440/2008

Methods.  Following a preliminary screening test in which no clinical signs of toxicity were noted at a concentration of 50% v/v, this concentration was selected as the highest dose investigated in the main test of the Local Lymph Node Assay. Three groups, each of five animals, were treated with 50 µl (25 µl per ear) of the test item as a solution in acetone/olive oil 4:1 at concentrations of 50%, 25% or 10% v/v. A further group of five animals was treated with acetone/olive oil 4:1 alone. A concurrent positive control test, using a group of five animals, was also performed with the known sensitiser,α‑Hexylcinnamaldehyde tech., 85%, at a concentration of 25% v/v in acetone/olive oil 4:1.

Results.  The Stimulation Index expressed as the mean radioactive incorporation for each treatment group divided by the mean radioactive incorporation of the vehicle control group are as follows:

Treatment Group

Concentration

Stimulation Index

Result

Test Item

10% v/v in

acetone/olive oil4:1

1.67(1.43)

Negative

25% v/v in

acetone/olive oil4:1

3.99

Positive

50% v/v in

acetone/olive oil4:1

4.14

Positive

Positive

Control Item

25% v/v in

acetone/olive oil4:1

8.93

Positive

The concentration of test item expected to cause a 3 fold increase in3HTdR incorporation (extrapolated EC3value) was calculated to be 18.6% with the exclusion of the outlier and 19.2% with the inclusion of the outlier.

Conclusion.  The test item was considered to be a sensitiser under the conditions of the test. The positive control item, α-Hexylcinnamaldehyde, tech., 85%, gave a Stimulation Index of greater than 3 when tested at a concentration of 25% v/v in acetone/olive oil 4:1.


Migrated from Short description of key information:
OECD 429 compliant LLNA study conducted under GLP, Klimisch grade 1.

Justification for selection of skin sensitisation endpoint:
GLP guideline study.

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

The substance tested positive in a LLNA with a stimulation index of > 3 at the upper two concentrations tested and, in accordance with ECHA Guidance on Application of the CLP Criteria (Version 4.0; November 2013), the test item is considered to be a moderate skin sensitiser (category 1B).