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EC number: 213-668-5 | CAS number: 999-97-3
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- Endpoint summary
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- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
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- Long-term toxicity to aquatic invertebrates
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- Toxicological Summary
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- Acute Toxicity
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Acute Toxicity: dermal
Administrative data
- Endpoint:
- acute toxicity: dermal
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- No data
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- comparable to guideline study with acceptable restrictions
- Remarks:
- The study was conducted according to a test protocol that is comparable to the appropriate OECD test guideline. It was not compliant with GLP.
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 1 981
- Report date:
- 1981
Materials and methods
Test guideline
- Qualifier:
- equivalent or similar to guideline
- Guideline:
- OECD Guideline 402 (Acute Dermal Toxicity)
- GLP compliance:
- no
- Test type:
- standard acute method
- Limit test:
- no
Test material
- Reference substance name:
- 1,1,1,3,3,3-hexamethyldisilazane
- EC Number:
- 213-668-5
- EC Name:
- 1,1,1,3,3,3-hexamethyldisilazane
- Cas Number:
- 999-97-3
- Molecular formula:
- C6H19NSi2
- IUPAC Name:
- bis(trimethylsilyl)amine
- Details on test material:
- - Name of test material (as cited in study report): Hexamethyldisilazane; Organofunctional Silane A-166; 1,1,1,3,3,3-hexamethyldisilazane.
No further details available
Constituent 1
Test animals
- Species:
- rabbit
- Strain:
- New Zealand White
- Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: No data
- Age at study initiation: No data
- Weight at study initiation: 2-3 Kg
- Fasting period before study: No data
- Housing:No data
- Diet (e.g. ad libitum): No data
- Water (e.g. ad libitum): No data
- Acclimation period: No data
ENVIRONMENTAL CONDITIONS
- Temperature (°C): No data
- Humidity (%): No data
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): No data
IN-LIFE DATES: No data
Administration / exposure
- Type of coverage:
- occlusive
- Vehicle:
- unchanged (no vehicle)
- Details on dermal exposure:
- TEST SITE
- Area of exposure: No data
- % coverage: No data
- Type of wrap if used: Impervious sheet
REMOVAL OF TEST SUBSTANCE
- Washing (if done): Yes
- Time after start of exposure: 24 hours
TEST MATERIAL
- Amount(s) applied (volume or weight with unit): Males: 1.0, 0.71 and 0.5 ml/kg bw; females: 16.0, 4.0, 1.0, 0.5 and 0.25 ml/kg bw
- Concentration (if solution): Undiluted
- Constant volume or concentration used: yes - Duration of exposure:
- 24 hours
- Doses:
- 1.0, 0.71, and 0.50 mL/kg bw (770, 550, and 385 mg/kg bw based on a density of 0.77 g/cm3) in males and 16.0, 4.0, 1.0, 0.5, and 0.25 mL/kg bw (12,320, 3080, 770, 385, 193 mg/kg bw based on a density of 0.77 g/cm3) in females
- No. of animals per sex per dose:
- Four (except 16 and 4 ml/kg bw levels used two females each)
- Control animals:
- not required
- Details on study design:
- - Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observations were made daily. Weights were measured before dosing and on Days 7 and 14.
- Necropsy of survivors performed: yes - Statistics:
- LD50s were calculated using the 'moving average method'.
Results and discussion
Effect levelsopen allclose all
- Key result
- Sex:
- male
- Dose descriptor:
- LD50
- Effect level:
- 585 mg/kg bw
- Based on:
- test mat.
- Key result
- Sex:
- female
- Dose descriptor:
- LD50
- Effect level:
- 544 mg/kg bw
- Based on:
- test mat.
- Mortality:
- Males: 4/4, 1/4 and 0/4 at 1.0, 0.71 and 0.5 ml/kg bw, respectively.
Females: 2/2, 2/2, 4/4, 0/4 and 0/4 at 16.0, 4.0, 1.0, 0.5 and 0.25 ml/kg bw, respectively. - Clinical signs:
- other: See Table 1
- Gross pathology:
- See Table 1
- Other findings:
- See table 1
Any other information on results incl. tables
Table 1 Summary of mortality, clinical and necropsy findings.
Group (ml/kg bw) | Number of deaths/total exposed | Time to death (d) | Clinical observations | Necropsy findings |
Males | ||||
0.5 | 0/4 | - | Sluggishness on Days 1 and 2 (2/4), skin erythema, edema, necrosis on Day 1 and desquamation by Day 14. | Trachea red (1/4), liver with tan foci (coccodiae; 1/4) |
0.71 | 1/4 | 3 | Prostration in one animal, skin erythema and necrosis, and scabs by Day 14. | Nothing remarkable |
1.0 | 4/4 | 1, 1, 2, 3 | Prostration in two animals, skin erythema, edema and necrosis | Lung & liver dark (1/4), trachea red (2/4), bladder distended filled with red/yellow liquid (1/4) |
Females | ||||
0.25 | 0/4 | - | Capillary injection, erythema, necrosis, spots of ecchymosis on Day 1, desquamation, scabs at 14 days. | Lungs mottled dark red (2/4) and trachea slight redness along mucous lining (1/4) |
0.5 | 0/4 | - | Sluggishness on Day 1, skin erythma, edema and necrosis on Day 1 with desquamation and scabs by Day 14. | Lungs and trachea dark red (1/4) |
1.0 | 4/4 | 1, 1, 1, 3 | Lethargy, slow and shallow breathing (1 hour), skin erythema and necrosis | Lungs mottled dark red (2/4) and trachea dark red (1/4) |
4.0 | 2/2 | 1, 1 | Signs of discomfort, lethargy slow and shallow breathing (30 mins), skin erythema and necrosis | Lungs with dark red patches |
16.0 | 2/2 | 0, 0 (within 2 hours) | Signs of discomfort, skin erythema and necrosis | Nothing remarkable |
Applicant's summary and conclusion
- Interpretation of results:
- Category 3 based on GHS criteria
- Remarks:
- Criteria used for interpretation of results: EU
- Conclusions:
- In an acute dermal toxicity study conducted according to a protocol that was comparable to OECD Test Guideline 402, but without information on GLP compliance, the LD50s for 1,1,1,3,3,3-hexamethyldisilazane (CAS 999-97-3) was concluded to be 544 mg/kg bw in females and 585 mg/kg bw in males (based on density of 0.77 g/cm3).
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