1,3,3,5-tetramethyl-1,1,5,5-tetraphenyltrisiloxane

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2002-05-10 to 2002-08-16

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

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:

1,3,3,5-tetramethyl-1,1,5,5-tetraphenyltrisiloxane

EC Number:

223-620-5

EC Name:

1,3,3,5-tetramethyl-1,1,5,5-tetraphenyltrisiloxane

Cas Number:

3982-82-9

Molecular formula:

C28H32O2Si3

IUPAC Name:

1,3,3,5-tetramethyl-1,1,5,5-tetraphenyltrisiloxane

Test material form:

other: liquid

Test animals

Species:

rat

Strain:

other: Crl: CD

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River, Germany
- Age at study initiation: 6-7 weeks
- Weight at study initiation: 209-224g for males and 183-193g for females
- Fasting period before study: 16 hours
- Housing: Makrolon cages
- Diet: Standard diet for rats and mice ssniff R/ M-H V 1530, discontinued 16 hours before treatment, ad libitum
- Water: tap water, ad libitum
- Acclimation period: Five days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22± 3
- Humidity (%): 55 ±15
- Air changes (per hr): No data
- 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: 1.9 ml/kg bw

Doses:

2000 mg/kg bw/day

No. of animals per sex per dose:

Three

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: before administration and immediately, 5, 15, 30 and 60 minutes and then 3, 6 and 24 hours after administration.
- Necropsy of survivors performed: yes
- Other examinations performed: during the follow-up period ( 14 days) changes of skin and fur, eyes and mucous membranes, respiratory and the circulatory, autonomic and central nervous system, somatomotor activity as well as behaviour pattern were observed at least once per day until all symptoms subsided, thereafter each working day. Attention was also paid to possible tremor, convulsions, salivation, diarrhoea, lethargy, sleep and coma. Observations on mortality were made at least once daily. Individual body weights were recorded before administration of the substance and thereafter in weekly intervals up to the end of the study, and at death. On test day 15, all surviving animals were sacrificed, dissected and examined macroscopically. A microscopic examination of all organs that showed evident lesions was performed on all animals that survived at least 24 hours. Autopsy and macroscopic inspections of animals that died prematurely would have been conducted as soon as possible after death.

Statistics:

No statistics carried out.

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Mortality:

No deaths.

Clinical signs:

No clinical signs of systemic toxicity.

Body weight:

No effects.

Gross pathology:

No abnormalities.

Other findings:

No effects.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In a good quality OECD 423 study conducted to GLP the LD50 was greater than the limit dose of 2000 mg/kg bw/day in rats, as no animals died at this dose. There were no signs of systemic toxicity.

Executive summary:

The test substance was administered orally by gavage to six CD rats (3/sex) at 2000 mg/kg bw. Animals were then observed daily and weekly determinations of body weight were conducted. Macroscopic examination was performed after terminal sacrifice on day 15. None of the six CD rats died, or showed clinical signs of systemic toxicity. All animals gained body weight within the study period, and no abnormalities were found at macroscopic postmortem examination of the animals. The oral LD₅₀ value for the test substance in CD rats was established to exceed 2000 mg/kg bw.