Registration Dossier

Administrative data

Description of key information

Oral (OECD 423, GLP, RL1), rat: LD 50 > 2000 mg/kg bw 
Inhalation (OECD 403, GLP, RL1), rat: LC50 > 11 200 mg/l
Dermal: No data available (data waiving according to Column 2 of REACH Annex VIII, Section 8.5.2)

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
discriminating dose
2 000 mg/kg bw
Quality of whole database:
The test was conducted according to the appropriate OECD test guideline, and in compliance with GLP.

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LC50
11 200 mg/m³
Quality of whole database:
The study was conducted according to an appropriate OECD test guideline, and in compliance with GLP.

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Acute toxicity: oral

In the available key study the test item (≥ 95% pure) was tested according to OECD TG 423 and in compliance with GLP (RCC, 1998a). 3 Wistar rats per sex received the test material in corn oil at a dose of 2000 mg/kg bw via gavage. No deaths occurred and no signs of toxicity were observed. Macroscopic evaluation revealed no abnormal findings. The LD50 for both males and females was found to be > 2000 mg/kg bw.

This result was further supported by a second oral toxicity study. The test item (91.5% pure) was tested according to OECD TG 423 and in compliance with GLP (LPT, 2002a). 3 Crl:CD rats of both sexes received the unchanged test material via gavage. No deaths occurred and no signs of toxicity were observed. Macroscopic evaluation revealed no abnormal findings. The LD50 for both males and females was found to be > 2000 mg/kg bw.

Acute toxicity: dermal

No data available. In accordance with Column 2 of REACH Annex VIII, the acute toxicity study via the dermal route (required in Section 8.5.2 of REACH Annex VIII) does not need to be conducted as reliable data via the oral and inhalation routes are available.

Acute toxicity: inhalation

In the available key study the test item (no data on purity) was tested according to OECD TG 403 and in compliance with GLP (Hoechst, 1986a). 5 Hoe:WISKf(SPF71) Wistar rats of both sexes were exposed to the test material via inhalation (aerosol) in a nose-only inhalation chamber for 4 hours. No deaths occurred and the clinical signs noted (irregular, fitfully and noisy breathing; gasping; salivation; long legged, uncoordinated- and staggering tread; prone position; retracted stomach flanks; sluggished or vanished corneal reflex and positional reflex and paw flick latency; anaesthesia; sneezing) were reversible within 4 days post exposure. Macroscopic evaluation revealed no abnormal findings. The LC50 for both males and females was found to be > 11 200 mg/l.

Justification for classification or non-classification

The available data on acute oral and inhalation toxicity of trimethoxy(2,4,4-trimethylpentyl)silane do not meet the criteria for classification according to Regulation 1272/2008 or EU Directive 67/548/EEC, and are therefore conclusive but not sufficient for classification.