1-Propanethiol, 3-(trimethoxysilyl)-, adduct with 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethylcyclohexane (1:1)

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)

Additional information:

Local Lymph Node Assay according to OECD 429 and Commission Regulation (EC) No 440/2008 of 30 May 2008, B.42 was performed with CBA/J@Rj mice. The aim of this study was to determine the skin sensitisation potential of Intermediate 36 following dermal exposure in the Local Lymph Node Assay. The test item was a light yellow liquid; vehicle compatibility was verified in a

Preliminary Compatibility Test with Acetone: Olive oil 4:1 mixture (AOO). The maximum available concentration was 100% in this vehicle. A Preliminary Irritation/Toxicity test was performed with the test item at concentrations of 100 % and 50 % in the selected vehicle. The applicability and biocompatibility of the test item on the ears of animals at the maximum concentration of test item of 100 % was acceptable. In the main assay twenty female CBA/J@Rj mice were allocated to 6 groups / 4 animals each:

- 3 groups received the appropriate formulation of Intermediate 36 at concentrations of 100 %, 50 %, 25 % and 10 %,

- the negative control group received the vehicle (AOO),

- the positive control group received 25 (w/v) % HCA in AOO

The test item solutions were applied on the dorsal surface of ears of experimental animals (25 l/ear) for three consecutive days (Days 1, 2 and 3). There was no treatment on Days 4, 5 and 6. On Day 6, the cell proliferation in the local lymph nodes was measured by incorporation of tritiated methyl thymidine (3HTdR) and the values obtained were used to calculate stimulation indices (SI).

No mortality or systemic clinical signs were observed during the study. No treatment related effect on the body weights was observed. Erythema and coated fur were observed in the 100 %, 50 % and 25% treated groups, erythema was observed at the 10 % treated group. Stimulation index values of the test item were 55.4, 91.5, 91.8, and 76.6 at treatment concentrations of 100, 50 %, 25 % and 10 %, respectively. α-Hexylcinnamaldehyde (25 (w/v) % dissolved in AOO) was used as a positive control to demonstrate the appropriate performance of the assay. A significant lymphoproliferative response (stimulation index value of 10.1) was noted for the positive control chemical and this result confirmed the validity of the assay.

In conclusion, under the conditions of the present assay Intermediate 36, tested in a suitable vehicle, was shown to have a strong sensitisation potential (sensitiser) in the Local Lymph Node Assay.

Migrated from Short description of key information:
Local Lymph Node Assay according to OECD 429 and Commission Regulation (EC) No 440/2008 of 30 May 2008, B.42 was performed with CBA/J@Rj mice. Under the conditions of the present assay Intermediate 36, tested in a suitable vehicle, was shown to have a strong sensitisation potential (sensitiser) in the Local Lymph Node Assay.

Respiratory sensitisation

Endpoint conclusion

Additional information:

no data

Migrated from Short description of key information:
no data

Justification for classification or non-classification

Intermediate 36 was shown to have a strong sensitisation potential and thus is classified as sensitiser in the Local Lymph Node Assay according to Directive 67/548/EEC and Regulation /EC) No 1272/2008 (CLP).