Registration Dossier

Administrative data

Description of key information

The key skin sensitisation study is a reliable adjuvant study conducted according to OECD 406 on a closely related material. The study identified a sensitization index of 5% (EU criteria for sensitization by skin contact would require a positive response in at least 30% of the test group).

Key value for chemical safety assessment

Skin sensitisation

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

The key study for sensitisation was read across from the related substance polysulfides, bis[3-(triethoxysilyl)propyl] (CAS 211519-85-6), conducted according to an appropriate OECD test guideline, and in compliance with GLP, and found the test material not sensitising (WIL 2000).

The sensitization index was reported to be 5%. EU criteria for sensitization by skin contact would require a positive response in at least 30% of the test group. The test substance contained a mixture of the registered substance and the related S3 and S4 isomers, but the relative proportions of each are not known.

The registered substance contains S2 as the main constituent, with S3 present as an impurity.The substance in the study used for read across, Polysulfides (CAS 211519 -85 -6), contained up to 25% of the registered substance. The other constituents are the structurally similar analogue substances S3 and S4. Due to the structural similarity and similar physicochemical properties, the read-across substance is considered to be representative of the registered substance, as the Polysulfides gave a clear negative result and there is no reason to expect a positive result from a higher proportion of S2 constituent. See discussion in the reproductive toxicity section endpoint summary (Section 7.8, section 5.9 for the CSR) for a more detailed justification for the read-across approach.


Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

Based on the available data, 4,4,13,13-tetraethoxy-3,14-dioxa-8,9-dithia-4,13-disilahexadecane does not require classification for sensitisation according to Regulation (EC) 1272/2008.