Reaction mass of decamethyltetrasiloxane; dodecamethylpentasiloxane; hexamethyldisiloxane; octamethyltrisiloxane

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Octamethyltrisiloxane

EC Number:

203-497-4

EC Name:

Octamethyltrisiloxane

Cas Number:

107-51-7

Molecular formula:

C8H24O2Si3

IUPAC Name:

Octamethyltrisiloxane

Test animals

Species:

rat

Strain:

other: Crl: CD (SD) IGS BR

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: ca. 11 weeks
- Weight at study initiation: 220-241 g
- Fasting period before study: over night
- Housing: Individually housed in suspended wire mesh cages
- Diet: Lab diet 5002 Certified Rodent Diet, ad libitum, except the night prior to dosing and approximately 4 hours post-dosing
- Water: ad libitum
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.1 -22.2
- Humidity (%): 46-65
- Air changes (per hr): 10.2-11.3
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

MAXIMUM DOSE VOLUME APPLIED: 2000 mg/kg

Doses:

2000 mg/kg

No. of animals per sex per dose:

3F

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days

- Frequency of observations and weighing: Animals were observed for clinical abnormalities immediately after dosing and then approximately 30 minutes, 90 minutes, four hours post dose and daily thereafter. The animals were examined for a minimum of the following changes in the skin and fur, eyes and mucous membranes, respiratory system, circulatory system, autonomic and central nervous system, motor activity and behaviour pattern. The body weights were recorded on study day 0 prior to dosing, on study day 7 and on study day 14 prior to terminal sacrifice.

- Necropsy of survivors performed: yes

- Other examinations performed: clinical signs, body weight, organ weights, histopathology, other: The gross necropsy included examination of the external surface, all orifices of the body and the cranial, thoracic and abdominal cavities and their contents.

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

There were no mortalities.

Clinical signs:

other: All animals appeared normal throughout the study.

Gross pathology:

No significant macroscopic findings were noted.

Other findings:

None reported.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

An LD50 value of >2000 mg/kg was determined in a reliable study conducted according to an appropriate test protocol, and in compliance with GLP.