1,1,5,5,5-hexamethyl-3-phenyl-3-[(trimethylsilyl)oxy]trisiloxane

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016-07-01 to 2016-08-17

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2001

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:

1,1,5,5,5-hexamethyl-3-phenyl-3-[(trimethylsilyl)oxy]trisiloxane

EC Number:

218-320-6

EC Name:

1,1,5,5,5-hexamethyl-3-phenyl-3-[(trimethylsilyl)oxy]trisiloxane

Cas Number:

2116-84-9

Molecular formula:

C15H32O3Si4

IUPAC Name:

1,1,5,5,5-hexamethyl-3-phenyl-3-[(trimethylsilyl)oxy]trisiloxane

Test material form:

liquid

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: at room temperature
- Stability under test conditions: stable
- Solubility and stability of the test substance in the solvent/vehicle: stable and soluble


TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: Preparation with corn oil yielded a solution and its homogeneity was maintained by vortexing the prepared formulation thoroughly before each dose administration

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River, Germany
- Females nulliparous and non-pregnant: yes
- Age at study initiation: 9 - 10 weeks old
- Weight at study initiation: 166 - 175 g
- Fasting period before study: 16 - 19 hours
- Housing: in groups in IVC cages, type III H, polysulphone cages on Altromin saw fibre bedding
- Diet: Altromin 1324 maintenance diet for rats and mice, ad libitum
- Water: tap water, ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3 °C
- Humidity (%): 55 +/- 10 %
- Air changes (per hr): 10x/ hour
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 2 g of the test item was dissolved in the vehicle to gain a final volume of 10 mL
- Justification for choice of vehicle: corn oil had non-toxic characteristics
- Lot/batch no. (if required): MKBV2080V


MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg body weight

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: The starting dose was selected to be 2000 mg/kg body weight, recommended in the OECD guideline for a limit test

Doses:

Step 1 and 2: 2000 mg/kg bw

No. of animals per sex per dose:

3 females per step

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Animals were weighed on day 1, 8 and 15. Clinical examinations were performed several times on the day of dosing, then daily until the end of the observation period.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, histopathology

Statistics:

Not used

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

>= 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred during the 14-day study period

Clinical signs:

other: No clinical signs of toxicity were noted at stage 1 or 2 in any of the test animals.

Gross pathology:

With the exception of acute injection of blood vessels in the abdominal region, which is due to the euthanasia injection, no specific gross pathological changes were recorded for any animal.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In the acute oral toxicity study, conducted according to an appropriate OECD test guideline and in compliance with GLP, the reported LD50 value for 1,1,1,5,5,5-hexamethyl-3-phenyl-3-[(trimethylsilyl)oxy]trisiloxane was >= 2000 mg/kg bw .