2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane

Endpoint summary

Description of key information

An acute oral LD50 of 12.3 ml/kg bw (equivalent to approximately 13161 mg/kg based on a density of 1.07 g/cm3), is reported in a study conducted according to a protocol equivalent to guideline but not in compliance with GLP (Mellon, 1962).

No reliable data are available for the inhalation route. 

An acute dermal LD50 of 6.30 ml/kg bw (equivalent to 6741 mg/kg bw, based on a density of 1.07 g/cm3), is reported in a study conducted according to a protocol equivalent to guideline but not in compliance with GLP (Mellon, 1962).

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

13 161 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

6 741 mg/kg bw

Quality of whole database:

The study was conducted according to a protocol equivalent to current guideline, but not in compliance with GLP.

Additional information

An acute oral LD₅₀ of 12.3 ml/kg bw (equivalent to approximately 13161 mg/kg based on a density of 1.07 g/cm³), is reported in a study conducted according to a protocol equivalent to guideline but not in compliance with GLP (Mellon, 1962). The animals became prostrate soon after test material administration, with most deaths occurring shortly after dosing. At necropsy, congested lungs, kidneys, stomachs, intestines and pale mottled livers with prominent acini were evident.

An acute dermal LD₅₀ of 6.30 ml/kg bw (equivalent to 6741 mg/kg bw based on a density of 1.07 g/cm³), is reported in a study conducted according to a protocol equivalent to guideline but not in compliance with GLP Mellon, 1962).Five male rabbits were exposed to the registered substance for 24 hours under occlusive coverage. Three out of five rabbits had convulsions on the first and second day after application. Deaths occurred on the first and second day after application. At necropsy, hemorrhage and congestion of the lungs, pale mottled livers with prominent acini, pale spleens, and pale mottled kidneys were evident. Bloody discharge was present around the nose and mouth of two animals.

A reliability 4 acute inhalation study is also available for the registered substance, which was conducted according to a scientifically acceptable protocol but is missing the analytical verification of exposure concentrations (Mellon, 1962). However, the study supports the low acute toxicity of the registered substance, with no reported deaths.

To support the approach for the oral repeated dose toxicity endpoint which uses the analogous substance beta-(3,4-epoxycyclohexyl) ethyltriethoxysilane (CAS 10217-34-2) as read-across, a supporting acute oral toxicity study (WIL, 1996) with the read-across substance is included to demonstrate that the registered substance and the read across substance have comparable toxicological profiles. The study reports an LD₅₀ value of >5000 mg/kg in rat (WIL 1996). Clinical signs observed during the study were dried red material around the eye(s), nose and/or mouth (7/10); wet and/or dried yellow urogenital and/or ventral abdominal staining (6/10) and hypoactivity (5/10). There were no other clinical findings and all animals appeared normal by day 4 or earlier and throughout the remainder of the study. There were no effects on body weight and no adverse necropsy findings.

Please refer to Section 7.5 Repeated dose toxicity for a more comprehensive discussion of read-across justification.

Justification for selection of acute toxicity – oral endpoint
The study was conducted according to a protocol equivalent to current guideline, but not in compliance with GLP.

Justification for classification or non-classification

Based on the available information, no classification and labelling is required for acute toxicity for 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane in accordance with Regulation (EC) No 1272/2008.