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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Description of key information

In a well-reported acute oral toxicity study conducted using a protocol similar to the now deleted OECD test guideline 401 (of unknown GLP status), the LD50 was <0.25ml/kg for undiluted organochlorosilane (214 mg/kg) (BRRC 1982). In an acute dermal toxicity study conducted using a protocol similar to OECD test guideline 402 (of unknown GLP status), the LD50 for Organochlorosilane A-161 was 2.38 ml/kg for males and 1.78 ml/kg for females (2037 and 1527 mg/kg, respectively, based on a specific gravity of 0.856) (BRRC 1982). In an acute inhalation study conducted according to OECD test guideline 403, the acute one-hour LC50 , based on nominal concentrations, was determined to be 4257 ppm (nominal; adjustment for exposure period gives LC50 of 2128.5 ppm) (Jean 1999).

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Dose descriptor:
LD50
Value:
214 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion
Dose descriptor:
LC50
Value:
9 458 mg/m³ air

Acute toxicity: via dermal route

Endpoint conclusion
Dose descriptor:
LD50
Value:
1 527 mg/kg bw

Additional information

The most reliable studies were selected as the key studies. Other available studies were not of sufficient quality to judge whether they support the key LD50s, but they do tend to show evidence of local irritancy effects. Since chlorotrimethylsilane is rapidly hydrolysed to trimethylsilanol and hydrogen chloride in the presence of moisture, adverse effects observed following acute exposure by all routes will be dominated by local corrosive effects, and other apparently adverse systemic effects could possibly be secondary to these local effects.

Justification for classification or non-classification

The test substance is labelled 'R20/21/22 Harmful by inhalation, in contact with skin and if swallowed', under Directive 67/548/EEC. Based on an LD50 of less than 214 mg/kg bw it is proposed that chlorotrimethylsilane be classified as Acute Toxic 3 under Regulation 1272/2008. Similarly, for the dermal route it is proposed that chlorotrimethylsilane be classified as Acute Toxic 4, based on the LD50 in males of 1527 mg/kg bw. An LC50 of 9.5 mg/l leads to the proposal that chlorotrimethylsilane be classified as Acute Toxic 3 for the inhalation route.