Dimethoxydimethylsilane

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

No test material purity is stated in the study report.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1979

Report date:

1979

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

yes

Remarks:

only limited information on test procedure and test material identity are given, and no test material purity is stated in the study report

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Diethoxy(dimethyl)silane

EC Number:

201-127-6

EC Name:

Diethoxy(dimethyl)silane

Cas Number:

78-62-6

Molecular formula:

C6H16O2Si

IUPAC Name:

diethoxy(dimethyl)silane

Details on test material:

- Name of test material (as cited in study report): Silicone A-164
- Physical state: light yellow liquid

Test animals

Species:

rat

Strain:

other: Wistar-derived

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 3 - 4 weeks
- Weight at study initiation: 90 - 120 g
- Fasting period before study: none
- Diet: ad libitum (not further specified)
- Water: ad libitum (not further specified)

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

MAXIMUM DOSE VOLUME APPLIED: 4.0, 8.0 and 16.0 mL/kg bw

Doses:

4.0, 8.0 and 16.0 mLkg bw

No. of animals per sex per dose:

5 males

Control animals:

no

Details on study design:

- Necropsy of survivors performed: yes

Results and discussion

Effect levels

Sex:

male

Dose descriptor:

LD50

Effect level:

11.3 mL/kg bw

Based on:

test mat.

95% CL:

8.22 - 15.6

Remarks on result:

other: equivalent to: LD50 = 9775 mg/kg bw

Mortality:

No mortality occurred at dose levels of 4.0 and 8.0 mL/kg bw, respectively. 5/5 animals died during the study period when administered the test material at a dose level of 16.0 mL/kg bw.

Clinical signs:

other: Clinical signs such as hyperactivity, unsteady gait and sluggishness were observed in animals of all dose groups within 2 - 15 min after test material administration. In addition, labored breathing was recorded in animals of the highest dose group within

Gross pathology:

Gross pathology of dead animals revealed red/pink mottled livers, red adrenals, distended stomachs (gas-filled), tan/pink mottled glandular portions, pink kidneys, distended intestines (containing liquids, gas and blood, red/yellow sections). No abnormalities were found in surviving animals.

Any other information on results incl. tables

Table 1: Summary of mortality data

Dose [mL/kg bw]	Mortality
	N
Males
4.0	0/5
8.0	0/5
16.0	5/5

Applicant's summary and conclusion

Interpretation of results:

other: CLP/EU GHS criteria are not met, no classification required according to Regulations (EC) No 1272/2008.

Conclusions:

In an acute toxicity study conducted with rats, an LD50 of 9775 mg/kg bw was established after animals were administered a single dose of 4.0, 8.0 and 16.0 mL/kg bw. No mortality occurred at dose levels of 4.0 and 8.0 mL/kg bw, respectively. All animals (5/5) died after administration of 16.0 mL/kg bw. Therefore, the test substance does not need to be classified for acute oral toxicity according to Regulation (EC) No 1272/2008.