3-[[3-[[(2-cyanoethyl)amino]methyl]-3,5,5-trimethylcyclohexyl]amino]propiononitrile

Endpoint summary

Description of key information

The test item has a skin sensitizing effect in the Murine Local Lymph Node Assay. The threshold concentration for sensitization induction was > 1 % < 10%.

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)

Additional information:

LLNA

The skin sensitizing potential of the test item was assessed using the nonradioactive variant of the Murine Local Lymph Node Assay. The assay simulates the induction phase for skin sensitization in mice. It determines the response of the auricular lymph nodes on repeated application of the test substance to the dorsal skin of the ears. Groups of 6 female CBA/Ca mice each were treated with 0.3%, 1 % and 10% w/w preparations of the test substance in acetone or with the vehicle alone. The study used 3 test groups and 1 control group. Each test animal was applied with 25 µL per ear of the respective test substance preparation to the dorsum of both ears for three consecutive days. The control group was treated with 25 µL per ear of the vehicle alone. Three days after the last application the mice were sacrificed and the auricular lymph nodes were removed. Lymph node response was evaluated by measuring the cellular content (indicator of cell proliferation) and weight of each animal's pooled lymph nodes. Moreover, a defined area with a diameter of 0.8 cm was punched out of the apical part of each ear and for each animal the weight of the pooled punches was determined in order to obtain an indication of possible skin irritation. The mean indices (fold of change as compared to the vehicle control) for lymph node weight, cell count and ear weight are summarized for each test group in the table below.

Test Group	Treatment	Lymph Node weight Index	Cell Count Index	Ear Weight Index
1	Vehicle acetone	1.00	1.00	1.00
2	0.3 % in acetone	1.07	1.19	0.99
3	1 % in acetone	0.99	1.08	0.99
4	10 % in acetone	2.83 ##	3.60 ##	1.03

The statistical evaluations were performed using the WILCOXON-test (## for p < 0.01 )

No signs of systemic toxicity were noticed. The test substance induced a statistically significant and biologically relevant response of the auricular lymph nodes when applied as 10% preparation in acetone. The ear weights were not statistically increased. In conclusion, the test item has a skin sensitizing effect in the Murine Local Lymph Node Assay. The threshold concentration for sensitization induction was > 1 % < 10 %.

An EC3 value was not derived.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Classification, Labelling, and Packaging Regulation (EC) No 1272/2008
The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008. As a result the substance is considered to be classified for as skin sensitizer category 1 under Regulation (EC) No 1272/2008, as amended for the eighth time in Regulation (EU) No 2016/218.