Trimethoxyoctylsilane

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

30.06.1987 to 31.07.1987

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

yes

Remarks:

No information on the purity of the TS, only two doses tested.

GLP compliance:

not specified

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Trimethoxyoctylsilane

EC Number:

221-338-7

EC Name:

Trimethoxyoctylsilane

Cas Number:

3069-40-7

Molecular formula:

C11H26O3Si

IUPAC Name:

trimethoxyoctylsilane

Test material form:

liquid

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Winkelmann Versuchstierzucht GmbH & Co. KG., D-4799 Borchen
- Age at study initiation: Males: 26-29 weeks; Females: 27-29 weeks
- Weight at study initiation: Males: 332-429 g; Females: 212-247 g
- Fasting period before study: 16 hours
- Housing: Individually in Makrolon cages Type II
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: At least five days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 2
- Humidity (%): 55 15
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: Not given but study period was 30.06.1987 to 31.07.1987

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

MAXIMUM DOSE VOLUME APPLIED: 5.11 ml/kg

Doses:

3236 and 4752 mg/kg

No. of animals per sex per dose:

Ten

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days for low dose and 21 days for high dose
- Frequency of observations and weighing: Behaviour and general condition were noted for the first 4-8 hours after dosing and then once daily. Mortality was checked twice daily. Body weights were recorded at the beginning and also 7, 14 and 21 days after administration.
- Necropsy of survivors performed: yes, a gross necropsy was performed on all animals. Macroscopic examination included external appearance, body orifices, body cavities and their contents.

Statistics:

None. LD50s estimated.

Results and discussion

Effect levels

Effect levels 1

Key result

Sex:

male

Dose descriptor:

LD50

Effect level:

ca. 5 000 mg/kg bw

Based on:

test mat.

Effect levels 2

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 3 500 mg/kg bw

Based on:

test mat.

Mortality:

See Table 1. Deaths occurred between day 4 and 17 after administration.

Clinical signs:

other: See Table 2. Following a dose of 3236 mg/kg bw there were coordination disturbances, piloerection, chromodacryorrhea, increased salivation and red nasal discharge. Following a dose of 4752 mg/kg bw there was additionally decreased muscle tone, loss of rig

Gross pathology:

At necropsy of the deceased female animals the small intestine was filled with a red liquid. The deceased male animals showed cryptorchism (incidental finding).

Any other information on results incl. tables

Table 1 Mortality data

Dose group (mg/kg bw)	Mortality rate		Time of death
	x/n	%	Hours post application	Days post application
Males
3236	0/5	0
4752	2/5	40		16 and 17
Females
3236	0/5	0
4752	3/5	60		Two on day 14 and one on day 8

Table 2 Clinical signs of toxicity

Symptom	Dose (mg/kg bw)
	Male 3236	Male 4752	Female 3236	Female 4752
Coordination disturbance	3	3	3	3
Slight tremor		1		1
Decrease of muscle tone AP		1		3
Loss of righting reflex LP/DP		1		3/3
Lacrimation				1
Chromodacryorrhea		2	1	2
Increased salivation	1		1	2
Red nasal discharge	1	2	1	2
Strenuous respiration		1		3
Piloerection	1	3	4	4
Diuresis/green urine				1/1
Vocalisation on handling		1
Opacity of the cornea				1

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In an acute oral toxicity study that was comparable to the now deleted OECD Test Guideline 401, but not in compliance with GLP (reliability score 2) the LD50 was at least 3500 mg/kg bw for male and female rats. Following a dose of 3236 mg/kg bw there were coordination disturbances, piloerection, chromodacryorrhea, increased salivation and red nasal discharge. Following a dose of 4752 mg/kg bw there was additionally decreased muscle tone, loss of righting reflexes and increased diuresis. Individually also, tremor, vocalisation on handling, lacrimation, opacity of the cornea and green discoloured urine occurred. The development of toxic effects was protracted, with coordination disturbances detected after two hours, and all other symptoms from days 2-5. All symptoms disappeared by day 21 of the observation period.