Dimethylbis(octadecyloxy)silane

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1995-08-02 to 1996-01-16

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Version / remarks:

1987

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Dimethylbis(octadecyloxy)silane

EC Number:

249-385-9

EC Name:

Dimethylbis(octadecyloxy)silane

Cas Number:

29043-70-7

Molecular formula:

C38H80O2Si

IUPAC Name:

dimethylbis(octadecyloxy)silane

Test material form:

other: solid

Test animals

Species:

rat

Strain:

other: CD(SD)BR

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Italia S.p.A., Calco (Como), Italy
- Age at study initiation: 5-6 weeks
- Weight at study initiation: 126-150 g
- Fasting period before study: overnight
- Housing: group of 5 of one sex in polycarbonate cages (59x39x20 cm) with stainless steel mesh lid and floor. Cages suspended over trays which held an absorbent material
- Diet: ad libitum (commercially available laboratory rodent diet - Altromin MT, A. Rieper S.p.A., Bolzano, Italy)
- Water: ad libitum
- Acclimation period: 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24°C
- Humidity (%): 45-65%
- Air changes (per hr): no information provided in study report
- 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: 200 mg/ml
- Amount of vehicle (if gavage): no information provided in study report
- Justification for choice of vehicle: no information provided in study report

MAXIMUM DOSE VOLUME APPLIED: 10 ml/kg

Doses:

2000 mg/kg

No. of animals per sex per dose:

5 male, 5 female

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: clinical signs: immediately upon dosing, approximately 1, 2 and 4 hours after dosing, daily thereafter; mortality: start of each working day and in the afternoon (final check at weekends carried out at approximately midday); body weight: days -1, 1 prior to dosing, 8 and 15
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs and body weight

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No animal died following treatment.

Clinical signs:

No significant clinical signs were observed following treatment with the test substance. Hair loss was observed from the neck of one animal on day 15.

Body weight:

Body weight changes were as expected for the strain and age of animal.

Gross pathology:

Necropsy revealed no abnormalities.

Any other information on results incl. tables

Table 1: Body weights

Sex	Animal number	Body weight (g) on day				Change in body weight (g) days 1-15
		-1	1	8	15
Male	22	198	177	264	319	142
	24	200	181	263	312	131
	26	216	186	272	323	137
	28	215	195	288	349	154
	30	193	172	252	301	129
	mean	204.4	182.2	267.8	320.8	138.6
Female	21	179	160	207	226	66
	23	161	148	180	200	52
	25	180	156	198	213	57
	27	177	150	208	224	74
	29	181	163	190	221	58
	mean	175.6	155.4	196.6	216.8	61.4

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In the key acute oral toxicity study, which was conducted according to OECD 401, compliant with GLP, the LD50 for dimethylbis(octadecyloxy)silane was >2000 mg/kg bw. There were no clinical signs of toxicity, effects on body weight or abnormal macroscopic findings.