Registration Dossier

Administrative data

Description of key information

In the key acute oral and dermal toxicity studies, the LD50 (rat) was greater than 2000 mg/kg (RCC Ltd., 1998 and BSL Bioservice, 2001a). The studies were carried out in accordance with OECD 423 and 402 respectively, and in compliance with GLP. There were no clinical signs of toxicity and no abnormalities were detected at scheduled necropsy. A supporting inhalation study is read-across from trimethoxy(2,4,4-trimethylpentyl)silane. In a good quality study (Hoechst, 1986a) exposure of wistar rats to an aerosol of trimethoxy(2,4,4-trimethylpentyl)silane at a concentration of 11.2 mg/l air did not cause any deaths. Therefore the LC50 was greater than 11.2 mg/l.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
2 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LC50
11 200 mg/m³

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
2 000 mg/kg bw

Additional information

The key acute oral and dermal toxicity studies are the only available data for these endpoints. Both studies are reliable, guideline studies, conducted in accordance with GLP. No mortality, clinical signs or necropsy findings were observed in either study.

The key acute oral and dermal toxicity studies are the only available data for these endpoints. Both studies are reliable, guideline studies, conducted in accordance with GLP. No mortality, clinical signs or necropsy findings were observed in either study.

No data are available for the inhalation route for the submission substance. Therefore, data are read-across from the related substance trimethoxy(2,4,4-trimethylpentyl)silane are read-across. The submission substance and trimethoxy(2,4,4-trimethylpentyl)silane are close structural analogues and both hydrolyse (with predicted half-lives at pH 7 of 43 hours and 5 hours, respectively) to give 2,4,4-trimethylpentylsilanetriol. The other hydrolysis products are ethanol and methanol, respectively.

Justification for classification or non-classification

Based on the available acute oral, dermal and inhalation toxicity studies, triethoxy (2,4,4-trimethylpentyl)silane is not classified for acute toxicity according to Regulation (EC) No. 1272/2008.