Triethoxysilane

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11-02-1994 to 22-03-1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This study was conducted according to the appropriate OECD test guideline and in compliance with GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

yes

Remarks:

; only two doses tested, the guideline required 3

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Triethoxysilane

EC Number:

213-650-7

EC Name:

Triethoxysilane

Cas Number:

998-30-1

Molecular formula:

C6H16O3Si

IUPAC Name:

triethoxysilane

Test animals

Species:

rat

Strain:

other: CDF® (F344)/Crl BR

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Not reported.
- Age at study initiation: Young adult.
- Weight at study initiation: 141 - 178 g
- Fasting period before study: The rats were fasted approximately 18-20 hours prior to dosing and returned to feed 3-4 hours after dosing.
- Housing:Individual suspended wire-mesh cages.
- Diet: Purina® Certified Rodent Chow® provided ad libitum
- Water: Municipal water were provided ad libitum
- Acclimation period: The animals were acclimated to laboratory conditions for a minimum of seven days prior to initiation of dosing.

ENVIRONMENTAL CONDITIONS
- Temperature : 68-76°F
- Humidity (%): 32-82
- Photoperiod (hrs dark / hrs light): 12/ 12.

IN-LIFE DATES: From: 20-04-1994 To: 21-05-1994

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

DOSAGE PREPARATION : The test material was dosed undiluted based on density (specific gravity).The dose volume was determined by dividing the dose level, expressed in g/kg, by the specific gravity (0.91 g/mL). Individual doses were calculated based on body weights taken just prior to dosing and appropriate dose volumes.

Doses:

1000 and 2000 mg/kg.

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The rats were observed at approximately 1.0, 3.0 and 4.0 hours post-dose on day 0 and twice daily (morning and afternoon) thereafter for 14 days for clinical observation and mortality. Body weights were obtained and recorded on Days -1, 0 (initiation), 7 and 14 (study termination).
- Necropsy of survivors performed: yes.Upon study termination, all rats were euthanized by carbon dioxide asphyxiation.
- Other examinations performed: clinical signs, body weight, organ weights, histopathology,cranial, thoracic and abdominal cavities were examined for all animals.

Statistics:

Not reported

Results and discussion

Effect levels

Effect levels 1

Sex:

male

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Effect levels 2

Sex:

female

Dose descriptor:

LD50

Effect level:

> 1 000 - < 2 000 mg/kg bw

Based on:

test mat.

Mortality:

There were three delayed deaths noted in the 2000 mg/kg bw female group, which occurred on study day 6, 7 and 10. All other animals survived through study termination (Day 14).

Clinical signs:

other: Ante mortem clinical findings included decreased defecation and urination, mucoid feces, hypothermia and prostration. For the surviving animals, clinical findings were noted in both dose groups, but findings for the male rats were limited to two of the 2

Gross pathology:

Gastrointestinal abnormalities and external mattings were noted for the three rats found dead. One rat had reddened adrenal glands. There were no other gross necropsy findings for animals that died during the study.
Motted lungs and ovarian cysts were noted at the scheduled necropsy for one and two rats, respectively. These findings were considered unrelated to the test material. There were no other significant changes observed for all examined tissues at necropsy.

Any other information on results incl. tables

Table 1. Summary.

Dose level (mg/kg)	Study Day												Total Mortality
	0		1		2		3		4		5-14
	M	F	M	F	M	F	M	F	M	F	M	F	M	F	C
1000	-	-	-	-	-	-	-	-	-	-	-	-	0/5	0/5	0/10
2000	-	-	-	-	-	-	-	-	-	-	-	3	0/5	3/5	3/10

M = Males F= Females C= Combined.

Applicant's summary and conclusion

Interpretation of results:

harmful

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

An acute oral toxicity study conducted according to the now deleted OECD 401 guideline and GLP, the LD50 of triethoxysilane was found to be greater than 2000 mg/kg for male albino rats and greater than 1000 mg/kg but less than 2000 mg/kg for female’s albino rats.