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EC number: 242-285-6 | CAS number: 18406-41-2
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
Acute Toxicity: inhalation
Administrative data
- Endpoint:
- acute toxicity: inhalation
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 1 993
Materials and methods
Test guideline
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 403 (Acute Inhalation Toxicity)
- Version / remarks:
- adopted May 12, 1981
- GLP compliance:
- yes
- Test type:
- traditional method
Test material
- Reference substance name:
- 3,3,6,6-tetramethoxy-2,7-dioxa-3,6-disilaoctane
- EC Number:
- 242-285-6
- EC Name:
- 3,3,6,6-tetramethoxy-2,7-dioxa-3,6-disilaoctane
- Cas Number:
- 18406-41-2
- Molecular formula:
- C8H22O6Si2
- IUPAC Name:
- 3,3,6,6-tetramethoxy-2,7-dioxa-3,6-disilaoctane
Constituent 1
Test animals
- Species:
- rat
- Strain:
- Fischer 344
- Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- EXPERIMENTAL ANIMALS:
Male and female Fischer 344 rats (weighing approximately 125-150 g and 7-8 weeks of age) were purchased from Charles River Breeding Laboratories, Kingston, New York. Upon arrival at the Toxicology Department, all rats were quarantined for 1 week. Approved rats were weighed and randomized into test groups (5/sex/group) using the Xylon ASLECT program. After randomization, animals were ear-tagged and color coded.
ANIMAL MAINTENANCE:
THe rats were housed individually in stainless steel wire mesh cages. Before the exposure, the rats were transferred into cages that were designed to be placed within the exposure chambers. After the exposure, the rats were returned to their oiriginal housing. The rats were fed Purina® rodent chow and water at libitum except during the exposure. Relative humidity ca. 40%, light/dark cycle 12/12 hours.
Administration / exposure
- Route of administration:
- inhalation: vapour
- Type of inhalation exposure:
- whole body
- Vehicle:
- air
- Details on inhalation exposure:
- EXPOSURE METHODS AND GENERATION EQUIPMENT:
Exposures were conducted in 2 m3 liter stainless steel whole body exposure chambers. The chambers were operated under dynamic conditions where the chamber air was room air, which had been filtered (hepa and charcoal filters). Airflow through the chambers were kept at approximately 12-15 air changes per hour. Chamber temperature, humidity, and airflow were monitored continuously and were recorded every five minutes by the Camile(R) Data Acquisition System during the exposure period. The test material was introduced into the chambers through special designed glass J-tubes. The test material was metered into the J-tubes with Harvard Apparatus syringe pumps. Instrument air which was filtered flowed through the J-tubes at a controlled rate. The air/vapor mixture passed into the inlet port at the top of the chambers. During the exposure period, attempts were made to keep the actual concentrations of the test material in the chambers as constant as possible.
The duration of the exposure period was four hours after equilibration of the chamber concentration. The equilibration time, which is a function of chamber airflow, was approximately 25 minutes. The amount of test material used during the exposure period was determined by pre- and post-measuring the weight of the test material in each syringe. The exposure duration (exposure period and equilibration time), test material uses and airflow through the chambers were then used to calculate nominal concentration values.
Actual chamber concentrations were measured a minimum of once an hour with an Analect(R) Diamond 20 FT-IR analyzer. The analyzer was calibrated before the start of the study. - Analytical verification of test atmosphere concentrations:
- yes
- Remarks:
- by means of FT-IR
- Duration of exposure:
- 4 h
- Concentrations:
- 0.5, 2.0, 4.0 and 6.0 ppm (target concentrations); 0.4, 2.0, 2.6 and 5.7 ppm (actual concentrations)
- No. of animals per sex per dose:
- 5
- Control animals:
- yes
- Details on study design:
- OBSERVATIONS:
All surviving rats were observed daily during the post-exposure period for treatment-related signs of toxicity, in particular, any evidence of respiratory, dermal, behavioral, nasal and/or ocular changes. The observation period was prolonged to further evaluate potential delayed toxicity.
BODY WEIGHT MEAUREMENTS:
Individual body weights were collected prior to exposure for animals in all groups. Also, body weights were collected on days 8, 15 and 23.
GROSS PATHOLOGY:
Necropsies were conducted on all animals which died spontaneously or at the termination of the study. Animals found dead after the working hours were refrigerated and necropsied on the next working day. - Statistics:
- Statistical analysis was conducted on mortality data. The Health and Environmental Science Probit Program was used to calculate the LC50 value.
Results and discussion
Effect levels
- Sex:
- male/female
- Dose descriptor:
- LC50
- Effect level:
- 2.4 ppm
- Exp. duration:
- 4 h
- Mortality:
- All animals died at the highest exposure concentration. One female rat died at 2.0 ppm and seven rats (5 males and 2 females) died at 2.6 ppm.
- Clinical signs:
- other: Test article-related additional clinical signs were observed at all exposure levels. Rales and nasal discharge were observed in animals exposed to 0.4 ppm. Additional clinical signs observed in the other exposure groups included labored breathing, corneal
- Body weight:
- Body weights were intially depressed in a dose-dependent manner after one week. Surviving animals were gaining weight by the end of the observation period.
- Gross pathology:
- None of the animals exposed to 0.4 ppm had any gross lesions. Gross necropsy observations of animals that died during the study consisted of severe upper respiratory tract irritation and corneal opacity. Corneal opacity was the only gross lesion that occurred to animals in the other exposure gorups that survived the observation period.
Any other information on results incl. tables
Summary of mortality data:
|
Number dead/number treated |
||
Target exposure concentration (ppm) |
Male |
Female |
Male/female combined |
0.5 |
0/5 |
0/5 |
0/10 |
2.0 |
0/5 |
1/5 |
1/10 |
4.0 |
5/5 |
2/5 |
7/10 |
6.0 |
5/5 |
5/5 |
10/10 |
Summary of mean body weight data (g) - males:
Target exposure concentration (ppm) |
Day of study |
|||
1 |
8 |
15 |
22 |
|
0.5 |
184.0 (N=5) |
177.0 (N=5) |
202.0 (N=5) |
225.0 (N=5) |
2.0 |
184.0 (N=5) |
121.0 (N=5) |
151.0 (N=5) |
186.0 (N=5) |
4.0 |
184.0 (N=5) |
129.0 (N=5) |
NA |
NA |
6.0 |
185.0 (N=5) |
120.0 (N=1) |
NA |
NA |
Summary of mean body weight data (g) - females:
Target exposure concentration (ppm) |
Day of study |
|||
1 |
8 |
15 |
22 |
|
0.5 |
148.0 (N=5) |
141.0 (N=5) |
151.0 (N=5) |
156.0 (N=5) |
2.0 |
149.0 (N=5) |
103.0 (N=5) |
127.0 (N=4) |
146.0 (N=4) |
4.0 |
148.0 (N=5) |
101.0 (N=5) |
112.0 (N=4) |
133.0 (N=3) |
6.0 |
149.0 (N=5) |
98.0 (N=3) |
NA |
NA |
Necropsy findings:
|
Male |
Female |
Disposition |
|
|
· Terminal sacrifice |
10/20 |
12/20 |
· Moribund sacrifice |
0 |
0 |
· Spontaneous death |
10/20 |
8/20 |
Animals within all groups having grossly normal tissues |
|
|
· Group I (0.5 ppm) |
3/5 |
5/5 |
· Group II (2.0 ppm) |
3/5 |
0 |
· Group III (4.0 ppm) |
0 |
1/5 |
· Group IV (6.0 ppm) |
0 |
0 |
Group II gross tissue changes |
|
|
· Eye: corneal opacity |
2/5 |
3/5 |
· Muzzle, vibrisses: porphyrin pigment |
0 |
1/5 |
· Hair, perineum: urine stained |
0 |
1/5 |
· Adipose tissue: atrophy, generalized |
0 |
2/5 |
· Stomach, mucosa: ulceration |
0 |
1/5 |
· Lung: congestion |
0 |
1/5 |
· Liver: congestion, mild |
0 |
1/5 |
· Liver: small |
0 |
1/5 |
· Thymus: small |
0 |
1/5 |
· Intestines: empty & gas distention |
0 |
1/5 |
Group III gross tissue changes |
|
|
· Eye: corneal opacity |
2/5 |
3/5 |
· Hair, muzzle, vibrisses: porphyrin pigment |
2/5 |
1/5 |
· Skin, perineum: feces stained |
1/5 |
0 |
· Skin, nose: reddened, bilateral |
2/5 |
0 |
· Nose: blood present |
0 |
1/5 |
· Dehydration |
3/5 |
2/5 |
· Adipose tissue: atrophy, generalized |
5/5 |
2/5 |
· Stomach: blood, intraluminal |
1/5 |
0 |
· Stomach: ulceration |
1/5 |
0 |
· Lungs: congestion |
5/5 |
2/5 |
· Lungs: atelectasis, minimal |
1/5 |
0 |
· Liver: congestion, mild |
2/5 |
2/5 |
· Liver: small |
2/5 |
2/5 |
· Intestines: small amount digested & gaseous distention |
5/5 |
2/5 |
Group IV gross tissue changes |
|
|
· Eye: corneal opacity |
1/5 |
3/5 |
· Hair, muzzle/forelegs: porphyrin pigment |
4/5 |
3/5 |
· Skin, perineum: feces stained |
2/5 |
0 |
· Skin, nose: reddened, bilateral |
2/5 |
1/5 |
· Nose: blood present |
2/5 |
0 |
· Adipose tissue: atrophy, generalized |
0 |
4/5 |
· Stomach: blood, intraluminal |
0 |
0 |
· Stomach: ulceration |
0 |
0 |
· Dehydration |
5/5 |
4/5 |
· Lungs: congestion |
5/5 |
2/5 |
· Lungs: atelectasis, minimal |
0 |
0 |
· Lungs: edema, minimal to mild |
4/5 |
3/5 |
· Intestines: small amount digested / gaseous distention |
5/5 |
2/5 |
· Adrenal gland, medulla: congestion |
3/5 |
0 |
· Liver: congestion, mild |
2/5 |
1/5 |
· Liver: small |
0 |
1/5 |
Applicant's summary and conclusion
- Interpretation of results:
- Category 1 based on GHS criteria
- Executive summary:
An acute vapor inhalation toxicity study was conducted to determine the four hour LC50 for DOW CORNING® X1-6154A Additive in Fischer 344/H rats. Four groups of ten animals (5/sex/group) were exposed for four hours to target concentrations of 0.5, 2.0, 4.0 and 6.0 ppm. The animals were observed for 23 days following the exposures.
The actual exposure concentrations, as determined by the Analect Diamond 20 FT-IR analyzer, were 0.4, 2.0, 2.6 and 5.7 ppm. All animals died at the highest exposure concentration. One female rat died at 2.0 ppm and seven rats (5 males and 2 females) died at 2.6 ppm. Test article-related clinical signs of toxicity were observed in all exposure groups. The primary clinical signs observed included nasal discharge, mouth breathing, rales and labored breathing. The severity of effects was the function of the exposure concentration.
None of the animals exposed to 0.4 ppm had any gross lesions. Gross necropsy observations of animals that died during the study consisted of severe upper respiratory tract irritation and corneal opacity. Corneal opacity was the only gross lesion that occurred to animals in the other exposure groups that survived the observation period.
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