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Toxicological information

Acute Toxicity: inhalation

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Administrative data

Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2001-07-06 to 2001-07-20
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
The highest concentration tested was not the maximum achievable concentration.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2001
Report Date:
2001

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 403 (Acute Inhalation Toxicity)
Deviations:
no
GLP compliance:
yes
Test type:
standard acute method
Limit test:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
gas

Test animals

Species:
rat
Strain:
Fischer 344
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Laboratories, Raleigh, North Carolina, RO2 Facility
- Age at study initiation: 8-9 weeks
- Weight at study initiation: Females: 128.3 - 134.3g; males: 166.1 - 173.4g
- Fasting period before study: no data
- Housing: Suspended wire-mesh cages above Bed-O'Cob bedding
- Diet: Purina Rodent Chow ad libitum
- Water: reverse osmosis treated tap water ad libitum
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 66-77°F, equivalent to 19-25°C
- Humidity (%): 30-70
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: approximately 10th June to: 20th July 2001

Administration / exposure

Route of administration:
inhalation: gas
Type of inhalation exposure:
whole body
Vehicle:
clean air
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Rochester-type, stainless steel and glass whole-body exposure chamber
- Exposure chamber volume: 450 litres
- Method of holding animals in test chamber: stainless steel wire mesh cages
- Source and rate of air: compressed air from Nash compressor at approx. 116 L/min
- Method of conditioning air: passed through Wilkerson model WRA-0025-01-1 dehumidifier and particulate filters (Matheson 460, Balston A915A-DX, A915A-Bx
- System of generating vapour: test article supplied in cylinder as liquefied gas. The cylinder was inverted such that the test article exited as a liquid, which was directed via stainless steel tubing to a heat-reacted (40-60 degrees C) metal J-tube containing a column of stainless steel ball bearings. A stream of compressed air was passed through the J-tube. The test article entering the J-tube was mixed with the air stream and then directed into the chamber inlet.
- Method of particle size determination: not applicable.
- Treatment of exhaust air: not stated
- Temperature, humidity, pressure in air chamber: 22.3 - 23.7 degrees C, 45.8-51.3% RH, -0.6" water.

TEST ATMOSPHERE
- Brief description of analytical method used: GC/FID
- Samples taken from breathing zone: yes

Analytical verification of test atmosphere concentrations:
yes
Duration of exposure:
4 h
Concentrations:
1774 ppm (1738-1827 ppm)
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: observed at least once daily, weighed Days 1, 8 and 15
- Necropsy of survivors performed: yes
Statistics:
Group mean values and standard error of the mean calculated by Microsoft Excel where appropriate.

Results and discussion

Effect levels
Key result
Sex:
male/female
Dose descriptor:
LC50
Effect level:
> 1 774 ppm
Based on:
test mat.
Exp. duration:
4 h
Remarks on result:
other: Equivalent to > 5400 mg/m³
Mortality:
None
Clinical signs:
other: None considered to be test article-related.
Body weight:
No treatment-related effects.
Gross pathology:
No treatment-related effects.

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
Trimethylsilane has been tested in accordance with OECD 403 and in compliance with GLP. No treatment-related effects were observed. It is concluded that the whole-body vapour inhalation LC50 value for trimethylsilane in the Fischer 344 rat is greater than 1774 ppm (5.4 mg/L, 5400 mg/m³), the highest concentration tested.