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EC number: 219-137-4 | CAS number: 2370-88-9
- 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
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Acute Toxicity: inhalation
Administrative data
- Endpoint:
- acute toxicity: inhalation
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 2001-2002
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- guideline study with acceptable restrictions
- Remarks:
- Only one dose, 5 mg/m3, top dose for vapours according to guideline version of 1981 but insufficient by today's gudieline version. Study does not meet the current classification cut-offs.
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 2 002
- Report date:
- 2001
Materials and methods
Test guideline
- Qualifier:
- equivalent or similar to guideline
- Guideline:
- OECD Guideline 403 (Acute Inhalation Toxicity)
- Version / remarks:
- modified: whole-body, 5M/5F, one dose of 5 mg/l (vapour)
- Deviations:
- yes
- Remarks:
- but not considered to have impacted the study outcome. (page containing Table with deviations missing)
- GLP compliance:
- yes
- Remarks:
- US-EPA TSCA GLP 40 CRF part 792
- Test type:
- standard acute method
- Limit test:
- yes
Test material
- Reference substance name:
- 2,4,6,8-tetramethylcyclotetrasiloxane
- EC Number:
- 219-137-4
- EC Name:
- 2,4,6,8-tetramethylcyclotetrasiloxane
- Cas Number:
- 2370-88-9
- Molecular formula:
- C4H16O4Si4
- IUPAC Name:
- 2,4,6,8-tetramethyl-1,3,5,7,2,4,6,8-tetroxatetrasilocane
- Reference substance name:
- 2,4,6,8,10-pentamethylcyclopentasiloxane
- EC Number:
- 228-204-7
- EC Name:
- 2,4,6,8,10-pentamethylcyclopentasiloxane
- Cas Number:
- 6166-86-5
- Molecular formula:
- C5H20O5Si5
- IUPAC Name:
- 2,4,6,8,10-Pentamethyl-1,3,5,7,9,2,4,6,8,10-pentaoxapentasilecane
Constituent 1
Constituent 2
Test animals
- Species:
- rat
- Strain:
- Sprague-Dawley
- Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- 5 male, 5 female rats, strain Sprague-Dawley, Crl:CD(SD)IGS;
At strat of study: age 9 weeks;
body weights females 201.8 - 227.7 grams;
body weights males 298.1-334.5 grams;
one group only;
identification by eartags and indivudual cage labels;
individually housed in wire-meshe cages elevated above absorbent material, regularly cleaned in accordance with good animal husbandry;
environmentally controlleed animal rooms;
artificial lighting, light/dark 12/12;
temperature 22+-3 degr.C , 30-70% relative humidity, 10-15 air changes /hr;
certified rodent deit ad lib except during exposure. reverse-osmosis purified tap water at lib.
Administration / exposure
- Route of administration:
- inhalation: vapour
- Type of inhalation exposure:
- whole body
- Vehicle:
- clean air
- Remarks:
- source: Nash air compressor AL-574; serial filters Matheson 460/461 and Balston 100-118-DX and 100-8-BX.Dilutuion air stream: HEPA-filtered, activated carbon filtered, warmed and humidified room air.
- Details on inhalation exposure:
- whole- body exposure.
limit test.
target concentration 450 ppm = 5 mg/l.
measured concentrations 445 ppm= 4.9 mg/l.
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Rochester-type, Stainless steel and glass whole-body exposure chamber;
- Exposure chamber volume: 450 liters;
- Method of holding animals in test chamber: stainless steel mesh caging;
- Source and rate of air: Room air, mean chamber airflow rate 105 +- 0.8 L/min. (14 air changes /hr) dilution air stream;
- method of conditioning; HEPA-filtered, activated carbon filtered, warmed and humidified room air;
- Temperature: 24.1 +-1.2 degr C;
- humidity: 49.7 +- 3% RH;
- pressure in air chamber:
- oxygen content: 20.9 degr. C;
TEST ATMOSPHERE
- Brief description of analytical method used: Varian Gas chromatograph 3400 with GC/IFD; one sample /30 minutes. Calibrated using 5 levels of bag standards in the range of 250-650 ppm;
- Samples taken from breathing zone: No.
VEHICLE
- Composition of vehicle: compressed, filtered air: - Analytical verification of test atmosphere concentrations:
- yes
- Remarks:
- See above for analytical method details. measured concentration showed good correlation with calculated nominal concentrations (4.3% difference)
- Duration of exposure:
- ca. 280 min
- Remarks on duration:
- 20 minutes lead time to build up to min. 99% of target concentration; 20 minutes end lag time to reduce concentrations to max 1% of target concentrations.
- Concentrations:
- mean measured chamber concentration: 4.9 +- 0.2 mg/l (445 +- 16.6 ppm)
See table in "any other observations on results" - No. of animals per sex per dose:
- 5 males, 5 females
- Control animals:
- no
- Details on study design:
- - Duration of observation period following administration: 14 days
- Frequency of observations:Mortality twice daily, once during weekends. Clinical signs: once daily
- Frequency of weighing: day1, prior to exposure; day 8; day 15 (prior to sacrifice)
- Necropsy of survivors performed: yes (complete gross pathology examination) - Statistics:
- not applicable: no mortality
Results and discussion
- Preliminary study:
- not performed.
Effect levelsopen allclose all
- Sex:
- female
- Dose descriptor:
- LC50
- Effect level:
- > 4.9 mg/L air (analytical)
- Based on:
- test mat.
- Exp. duration:
- 4 h
- Remarks on result:
- other: Also incuding 20 min. lead time and 20 min. lag time
- Sex:
- male
- Dose descriptor:
- LC50
- Effect level:
- > 4.9 mg/L air (analytical)
- Based on:
- test mat.
- Exp. duration:
- 4 h
- Remarks on result:
- other: Also incuding 20 min. lead time and 20 min. lag time
- Mortality:
- None
- Clinical signs:
- other: None
- Body weight:
- Body weight ranges and body weight gains were within acceptable ranges throughout duration of the study (barring one deviation) (Table individual body weight gains missing)
- Gross pathology:
- No gross pathology findings
- Other findings:
- none reported
Any other information on results incl. tables
Conditions during exposure. |
|||||
Time point (30 min. intervals) |
Measured conc. (ppm) |
Measured conc. (mg/l) |
Temperature (°C) |
Humidity (%RH) |
Air flow (L/min) |
1 |
N.A. |
N.A. |
21.6 |
53.1 |
106 |
2 |
414 |
4.5 |
22.7 |
53.2 |
106 |
3 |
425 |
4.7 |
23.3 |
51.5 |
105 |
4 |
444 |
4.9 |
23.9 |
47.4 |
105 |
5 |
446 |
4.9 |
24.7 |
44.8 |
105 |
6 |
446 |
4.9 |
25.0 |
48.4 |
105 |
7 |
460 |
5.0 |
25.0 |
53.7 |
105 |
8 |
444 |
4.9 |
24.8 |
48.8 |
105 |
9 |
456 |
5.0 |
24.9 |
48.2 |
105 |
10 |
467 |
5.1 |
24.8 |
48.0 |
103 |
Mean |
445 |
4.9 |
24.1 |
49.7 |
105 |
SD |
16.6 |
0.2 |
1.2 |
3.0 |
0.8 |
Applicant's summary and conclusion
- Interpretation of results:
- GHS criteria not met
- Conclusions:
- The test substane is a mixture of the submission substance, 2,4,6,8-tetramethylcyclotetrasiloxane (CAS 2370-88-9) and 2,4,6,8,10-pentamethylcyclopentasiloxane (CAS 6166-86-5). These substances are structurally very closely related and, as shown in the hydrolysis test (see 5.1.2) will probably result in similar or identical hydrolysis product in contact with water. The results for the mixture are therefore considered to be applicable to both substances individually. No mortality was seen after a 4-hour exposure to a mean measured concentration of 4.9 mg/l or during a 14-day observation. The LC50 is considered to be greater than 4.9 mg/l.
The selected single dose is in the range of 2- Executive summary:
An acute inhalation study was performed with a mixture of 2,4,6,8,10-pentamethylcyclopentasiloxane (CAS 6166-86-5) and 2,4,6,8-tetramethylcyclotetrasiloxane. Five male and five female animals were exposed in a whole-body exposure chamber for 4 hours and subsequently observed for 14 days. Only one dose was tested: nominal 5 mg/l, measured 4.9 mg/l. No mortalitiy or any clinical signs were observed. The LC50 of the mixture is > 4.9 mg/l.
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