tert-butylchlorodimethylsilane

Endpoint summary

Description of key information

The acute oral LD₅₀was found to be >2000 mg/kg in a study conducted according to OECD 423 and in compliance with GLP.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18 April to 28 June 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

other: CD/Crl:CD

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River GmbH, Germany
- Age at study initiation: 41 or 42 days
- Weight at study initiation: 194-231 g (males), 175-208 g (females)
- Fasting period before study: yes
- Housing: Makrolon Type III cages with granulated textured wood (Granulate A2) bedding
- Diet (ad libitum): ssniff R/M-H V 1530
- Water (ad libitum): tap water
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-25
- Humidity (%): 40-70
- Air changes (per hr): not stated
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: June 2002

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 200 mg/mL
- Amount of vehicle (if gavage): 10 mL/kg
- stability in vehicle: > 1 day at +4 degrees C in the dark

Doses:

2000 mg/kg

No. of animals per sex per dose:

3 per sex

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: pre-dose, 5, 15, 30 and 60 minutes, 3, 6 and 24 hours after dosing, then daily. Body weights: weekly
- Necropsy of survivors performed: yes

Statistics:

Means and standard deviations

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

One male found dead on Day 3

Clinical signs:

other: One female was noted to have reduced mobility, ataxia and slightly reduced muscle tone between 15 and 60 minutes after dosing.

Gross pathology:

In the male that died on Day 3, intestine filled with gas and dark contents was recorded.

Interpretation of results:

GHS criteria not met

Conclusions:

The acute oral LD50 of tert-butyl(chloro)dimethylsilane in CD rats was greater than 2000 mg/kg in a study conducted according to OECD 423 and in compliance with GLP.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

2 000 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 study available

Additional information

In the key acute oral study (LPT, 2002), tert-butyl(chloro)dimethylsilane was administered in corn oil by oral gavage to 3 male and 3 female rats. One male was found dead on Day 3 and at necropsy, the intestine was noted to contain gas and dark contents. Clinical signs of reduced mobility, ataxia and reduced muscle tone were noted for one female between 15 and 60 minutes after dosing. There were no other remarkable findings and the oral LD₅₀ was considered to be >2000 mg/kg.

Justification for classification or non-classification

Based on the available data tert-butyl(chloro)dimethylsilane does not require classification for acute toxicity according to Regulation (EC) No 1272/2008.