Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1998/01/26-1998/02/12
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study was conducted according to the appropriate OECD guideline, and in compliance with GLP.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1998
Report Date:
1998

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Principles of method if other than guideline:
There were no deviations from the protocol.
GLP compliance:
yes
Test type:
standard acute method
Limit test:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent

Test animals

Species:
rat
Strain:
other: HsdCpb:WU/SPF
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS

- Source: Harlan Winkelmann GmbH, Gartenstrasse 27, 33176 Borchen

- Age at study initiation: young adults

- Weight at study initiation: per sex the weight variation did not exceed +/- 20% of the mean body weight

- Fasting period before study: 16 hours

- Housing: Makrolon type 3 cages, group-caged by sex, each cage containing max. five rats

- Diet: Ssniff R 10 diet in pellete form, ad libitum, except that animals were fasted prior to substance administration for a period of about 16 hours. 3 hours after application food was offered ad libitum.

- Water: tap water, ad libitum

- Acclimation period: minimum of 5 days


ENVIRONMENTAL CONDITIONS

- Temperature (°C): 22 +/- 3

- Humidity (%): 30-70%

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

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
unchanged (no vehicle)
Details on oral exposure:
MAXIMUM DOSE VOLUME APPLIED: 3.11 cm3/kg bw

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: in the first step three male rats were given a single oral application of the test substance at a limit dose of 2000 mg/kg bw. SInce no mortalities occurred within 24 hours p.a., three female rats were treated the same way.
Doses:
2000 mg/kg bw
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: Rats were checked at least twice daily for any mortalities. Animals were observed soon after dosing and at frequent intervals for the remainder of the day of dosing (ca. 6 hours). On subsequent days animals were observed once a day. The nature and severity of the clinical signs and time were recorded at each observation. Individual bodyweights were recorded on days 0 (prior to dosing), 7 and 14.

- Necropsy of survivors performed: yes, animals were killed on day 14 by CO2 inhalation

- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other: All animals were subjected to macroscopic examination after opening the abdominal and thoracic cavities. The macroscopic appearance of all examined tissues was recorded for each animal.
Statistics:
No statistical analysis was carried out.

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Mortality:
There were no mortalities in response to exposure.
Clinical signs:
Clinical symptoms were noticed 30 minutes to six hours after treatment. Abnormal gait, squatting position, sedation, paddling movements, piloerection, diarrhea and diuresis were observed. From day one until the end of the study (day 14) no other clinical signs were observed.
Body weight:
All animals achieved satisfactory bodyweight gains throughout the study.
Gross pathology:
The macroscopic examination revealed no abnormalities.
Other findings:
No other findings reported.

Any other information on results incl. tables

The oral LD50 value of tetramethylsilane was found to be >2000 mg/kg for male and female rats.

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
The oral LD50 value of tetramethylsilane was found to be >2000 mg/kg for male and female rats.