Tetramethyl orthosilicate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

2001/01/29 - 2001/04/02

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to the appropriate OECD test guideline, and in compliance with GLP, and is therefore considered to be reliability 1. Read-across of the result is considered to be reliability 2.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Test type:

other: LD50

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Tetraethyl orthosilicate

EC Number:

201-083-8

EC Name:

Tetraethyl orthosilicate

Cas Number:

78-10-4

IUPAC Name:

tetraethyl orthosilicate

Details on test material:

- Name of test material (as cited in study report): SPLG 396

- Substance type: Silicate

- Physical state: white to grey liquid

- Storage condition of test material: room temperature

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS

- Source: Harlan Winkelmann GmbH, Borchen, Districts of Paderborn

- Age at study initiation: ca. 8 weeks

- Weight at study initiation: 185-187g males, 159-175g females

- Housing: During the acclimatization period the animals were kept conventionally in polycarbonate cages type III (animals <180g bw - five animals, of >180g - max three animals per cage) The cages were changed at least three times a week. feed racks and water bottles were not changed. During the test period the animals were kept conventionally in polycarbonate cages type III (three animals per cage). the cages were changed at least once a week. Feed racks and water bottles were not changed. The bedding consisted of low -dust wood granules type BK 8/15.

- Diet: "NAFAG No.9439 Long Life W 10", ad libitum (approx. 2 hours after administration)

- Water: tap water, ad libitum

- Acclimation period: minimum of 5 days


ENVIRONMENTAL CONDITIONS

- Temperature (°C): 22 +/- 2C

- Humidity (%): 55 +/- 5%

- Air changes (per hr): ca. 15-20

- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

polyethylene glycol

Details on oral exposure:

MAXIMUM DOSE VOLUME APPLIED: 5ml/kg


DOSAGE PREPARATION (if unusual): The test substance was formulated in polyethylene glycol 400 before administration. The applied formulations were well mixed by pumping the syringe several times.

Doses:

2000 mg/kg

No. of animals per sex per dose:

3M, 3F

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days

- Frequency of observations and weighing: Appearance and behaviour were recorded several times on the day of treatment, and at least once a day thereafter. Where sign occurred, the type, period and intensity were determined individually. The body weights of the rats were recorded on day 1 before administration and then weekly. Additionally, all animals that died or were sacrificed were weighed.

- Necropsy of survivors performed: yes

- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other: During clinical observation all abnormal findings were registered and particular attention was paid to the following organ systems, localizations and physiological functions: fur, skin colour, edemas, eyes, lacrimation, nasal discharge, salivation, grooming, vocalization, excitememnt, aggression, digging and preening movements, cannibalism, nervous system - reactivity, motility, reflexes, gait, paralysis, spasms, tremors, where accessible respiration frequency and heart rate, posture, and appearance of feces etc.

Statistics:

No statistical analysis was carried out.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 500 mg/kg bw

Based on:

test mat.

Mortality:

There were no test substance related deaths.

Clinical signs:

other: There were no clinical signs.

Gross pathology:

No gross pathologic changed were observed in animals sacrificed at the end of the study period.

Other findings:

No other findings reported.

Any other information on results incl. tables

There were no deaths in response to the test material.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

An LD50 value for tetraethyl orthosilicate of >2500 mg/kg was determined in a reliable study conducted according to an appropriate test protocol, and in compliance with GLP.