Registration Dossier

Administrative data

Description of key information

In the key skin sensitisation study, conducted according to OECD TG 406 and in compliance with GLP, the test substance, 1, 1, 1, 3, 5, 5, 5-heptamethyl-3-octyltrisiloxane, was reported to be not sensitising to the skin of guinea pigs (Eurofins, 2016).

Key value for chemical safety assessment

Skin sensitisation

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

In the key skin sensitisation study, conducted according to OECD TG 406 and in compliance with GLP, the test substance, 1, 1, 1, 3, 5, 5, 5-heptamethyl-3-octyltrisiloxane, was reported to be not sensitising to the skin of guinea pigs (Eurofins, 2016).

At induction, 0.5 ml of undiluted test material was applied topically onto the skin of the right flanks of 20 guinea pigs for 6 hours under occlusive dressing. Three applications were performed at weekly intervals for three weeks. An empty Hill Top Chamber was applied to the test area of the negative control animals. The same procedure was used for both test and negative control groups.

At challenge, 14 days after the last induction application 0.5 ml of 0.75% test substance in acetone was applied on the right flank of test and negative control animals for 6 hours under occlusive dressing. Simultaneously, 0.5 ml of acetone was applied on the left flank of both test and negative control group animals for 6 hours under occlusive dressing. Approximately 24 and 48 hours after removal of the test item the skin reactions were observed and recorded. All animals were observed for signs of toxicity daily throughout the study period. Body weights were recorded prior to the first application and at the end of the observation period.

No mortality occurred during the study period. Neither erythema nor oedema were observed in any of the animals at any time of observation. There was no evidence of sensitisation in any of the animals.

Two supporting skin sensitisation studies, conducted according to OECD TG 406 and in compliance with GLP, were also available and reported the test item to be not sensitising to guinea pig skin (WIL Research, 1999; Aventis, 2001).

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

Based on the available data for 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane, no classification is required for sensitisation according to Regulation (EC) No. 1272/2008.