Dichloro(methyl)(phenyl)silane

Endpoint summary

Description of key information

The key acute oral study was conducted according to OECD 423 (Acute Toxic Class method), giving an LD50 for dichloro(methyl)(phenyl)silane male and female rats in the range > 200 - < 2000 mg/kg when dosed in corn oil ( LPT Laboratory of Pharmacology and Toxicology, 2002). Clinical signs observed included reduced motility, ataxia, reduced muscle tone, dyspnoea, lateral position and ptosis at the higher dose level. At the lower dose level no animals showed any signs of systemic toxicity. No abnormalities were found at macroscopic post mortem examination of the animals. No microscopic examination of tissues was performed.

There are no inhalation or dermal acute toxicity studies for dichloro(methyl)(phenyl)silane.

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:

04.03.2002 to 10.06.2002

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

There were minor deviations from the guideline with respect to selection of dose levels.

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

Doses of 2000 and 200 mg/kg bw were used, the guideline recommends 2000 followed by 300 mg/ kg bw.

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

no

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: at room temperature, in dark, tightly closed, dry
- Stability under test conditions: stable
- Solubility and stability of the test substance in the solvent/vehicle: soluble and stable for 1 day in corn oil

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: The test substance was used as supplied at the highest dose tested (2000 mg/kg bw) and corn oil was used as vehicle at 200 mg/kg bw.
- Preliminary purification step (if any): not specified

Species:

rat

Strain:

Crj: CD(SD)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland GmbH
- Age at study initiation: male: 41 days, female: 48 days
- Weight at study initiation: male: 173-213 g; female: 163-173 g
- Fasting period before study: 16 hours before administration of test substance, only tap water ad libitum was available
- Housing: during 14 day observation period groups of 2 -3 animals in MAKROLON cages (type III).
- Diet (e.g. ad libitum): ssniff R/M-H V 1530 (ssniff Spezialiäten GmbH)
- Water: drinking water ad libitum
- Acclimation period: at least 5 adaption days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22°C+-3°C
- Humidity (%): 55% +-15%
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 200 mg/l
- Administration volume: 1.69 ml/kg bw
- Lot/batch no. (if required):81K2204, SIGMA ALDRICH Chemie GmbH

MAXIMUM DOSE VOLUME APPLIED: 2000 mg/kg b.w. without vehicle
Administration volume: 1.69 ml/kg b.w.

Doses:

2000 mg/kg bw without vehicle
200 mg/kg bw in vehicle (corn oil)
Administration volume: 1.69 ml/kg bw

No. of animals per sex per dose:

2000 mg/kg bw: 3 (male) animals
200 mg/kg bw: 3 male, 3 female

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: before and immediately at 5, 15, 30 and 60 minutes, as well as 3, 6, and 24h after administration, all surviving animals once a day until all symptoms subsided, thereafter each working day. Observations on mortality once daily, individual body weights were recorded before administration and thereafter in weekly intervals up to the end of the study
- Necropsy of survivors performed: yes

Statistics:

No statistical analysis was performed, the method used was not intended to allow the calculation of a precise LD50 value.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

>= 200 - < 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

not determinable

Mortality:

2000 mg/kg bw resulted in the death within 30 min of all (male) animals
200 mg/kg bw: one of 3 male and none of 3 female animals died prematurely (within 7 days)

Clinical signs:

other: 2000 mg/kg bw: reduced motility, ataxia, reduced muscle tone, dyspnoea, lateral position, ptosis 200 mg/kg bw: no animals showed any signs of systemic toxicity.

Gross pathology:

No abnormalities were found at macroscopic post mortem examination of the animals.

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

A reliable study conducted according to OECD 423 and in accordance with GLP, identified an acute oral LD50 value of 200 - 2000 mg/kg bw in male and female rats.
6

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

200 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

The key oral study was selected as the only available reliable study. It was a GLP-compliant, guideline study (reliability 2).

In a non-guideline, non-GLP acute inhalation study, the deaths of all five rats during or within 1 h of a 7 h exposure to an atmosphere saturated with the test material were reported (Dow Corning Corporation, 1969).

Justification for classification or non-classification

On the basis of the available information, dichloro(methyl)(phenyl)silane is not classified for acute toxicity according to Regulation (EC) No 1272/2008.