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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
30-08-1988 to 12-09-1988
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study was conducted according to the appropriate OECD test guideline, and in compliance with GLP.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1989
Report date:
1989

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 403 (Acute Inhalation Toxicity)
Deviations:
yes
Remarks:
Report lacking data on whether clinical examination and physical measurements were conducted.
GLP compliance:
yes
Test type:
standard acute method
Limit test:
yes

Test material

1
Chemical structure
Reference substance name:
Dimethoxydimethylsilane
EC Number:
214-189-4
EC Name:
Dimethoxydimethylsilane
Cas Number:
1112-39-6
Molecular formula:
C4H12O2Si
IUPAC Name:
dimethoxydimethylsilane
Details on test material:
- Name of test material (as cited in study report): Dimethyldimethoxysilane
- Substance type: Alkoxysilane
- Physical state: A clear liquid

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Not reported.
- Weight at study initiation: 175-200 g ( Males and Females).
- Housing: The rats were housed in stainless steel, wire mesh bottomed cages of conventional design. At the onset of experiment, the animals were moved into special stainless steel cages. These cages were designed to house the animals during the exposure periods. The animals were returned to their original housing after the exposure period.
- Diet : The animals were fed PURINA Rodent Chow ad libitum except during the exposure period.
- Water : The animals were fed water ad libitum except during the exposure period.


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 30 -50
- Air changes (per hr): 14 - 15 air changes per hour
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: Not reported

Administration / exposure

Route of administration:
inhalation: vapour
Type of inhalation exposure:
whole body
Vehicle:
air
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Exposure was conducted in stainless steel and glass exposure chambers. The chambers were operated under dynamic conditions.
- Exposure chamber volume: 450-litre
- Method of holding animals in test chamber: Not reported.
- Source and rate of air: Airflow rates through the chambers were monitored continuously by calibrated Magnehelic gauges connected across orifices at the chamber inlets.
- Method of conditioning air: Not reported
- System of generating particulates/aerosols: Test material was introduced into the test chamber through a specially designed glass J-tube with a flow FMI Lab pump. Laboratory air filtered with a Matheson 462 cartridge filter passed through the J-tube. The air/vapour mixture entered the top of the chamber where it was diluted with room air. Heating tape was used to heat the air which passed through the J-tube, and glass beads were used to further help vaporize the test material. After the exposure period, the vapour generating equipment was turned off and the vapour concentration in the chamber was allowed to return to zero.
- Method of particle size determination: Not reported.
- Treatment of exhaust air: The exhaust air was filtered (hepa and carbon), cleaned with a water cyclone, then exhausted from the roof of the building.
- Temperature, humidity, pressure in air chamber: Chamber temperature and relative humidity were monitored with Cole-Parmer Model No.3310-40 (certified) temperature and humidity gauges.

TEST ATMOSPHERE
- Brief description of analytical method used: Not reported


Analytical verification of test atmosphere concentrations:
not specified
Duration of exposure:
4 h
Concentrations:
The test material target concentration was 5.0 mg/l. The actual nominal chamber concentration was 4.7 mg/l (calculation by weight).
No. of animals per sex per dose:
5 males and 5 females.
Control animals:
yes
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Gauge readings were recorded hourly during the chamber period. Animals were observed once a day during weekdays. Individual animal body weights were taken prior to exposure and on days 7 and 14 after exposure.
- Necropsy of survivors performed: Not reported
- Other examinations performed: body weight

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LC50
Effect level:
> 4 700 mg/m³ air
Based on:
test mat.
Exp. duration:
4 h
Mortality:
No mortalities were observed in either groups during the exposure or post-exposure periods.
Clinical signs:
other: Not reported.
Body weight:
No apparent test material related effect on body weights.
Gross pathology:
Not reported.

Any other information on results incl. tables

 Table 2. Mortality Data.

Test Material Concentration (mg/l)

Number of Dead/Number exposed

Males

Females

0

0/5

0/5

4.7

0/5

0/5

 

Table 3. Mean Body Weight Data (g).

Days After Exposure

Group I, Control

Test Group II

Males

Females

Males

Females

0

189 ± 5

183 ± 10

188 ± 5

183 ± 12

7

242 ± 8

214 ± 15

248 ± 9

205 ± 15

14

295 ± 13

233 ± 21

305 ± 15

230 ± 20

Applicant's summary and conclusion

Interpretation of results:
other: CLP/EU GHS criteria are not met, no classification required according to Regulation (EC) No 1272/2008
Conclusions:
In an acute inhalation (vapour) study conducted in compliance with OECD 403 and GLP, in which rats were exposed to to >4700 mg/m³ dimethoxydimethylsilane for four hours resulted in no mortality. Therefore, LC50 was determined to be >4700 mg/m³.