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EC number: 202-485-6 | CAS number: 96-17-3
- 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:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Comparable to guideline study with acceptable restrictions (no concentrations and particle size distribution measured, only 6 rats used, sex not specified, reporting not according to test guideline)
Data source
Referenceopen allclose all
- Reference Type:
- publication
- Title:
- Unnamed
- Year:
- 1 974
- Report date:
- 1974
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 1 970
- Report date:
- 1970
Materials and methods
Test guideline
- Qualifier:
- equivalent or similar to guideline
- Guideline:
- OECD Guideline 403 (Acute Inhalation Toxicity)
- Deviations:
- yes
- Remarks:
- : no concentrations and particle size distribution measured, only 6 rats used, sex not specified, reporting not according to test guideline
- Principles of method if other than guideline:
- Pre-guideline study, but method is similar to OECD TG 403. A test with graduate doses (standard test) and an inhalation hazard test were performed.
- GLP compliance:
- no
- Remarks:
- pre-GLP study
- Test type:
- standard acute method
- Limit test:
- no
Test material
- Reference substance name:
- 2-methylbutyraldehyde
- EC Number:
- 202-485-6
- EC Name:
- 2-methylbutyraldehyde
- Cas Number:
- 96-17-3
- Molecular formula:
- C5H10O
- IUPAC Name:
- 2-methylbutanal
- Details on test material:
- - Name of test material (as cited in study report): 2-Methylbutyraldehyde
- no further information on test substance
Constituent 1
Test animals
- Species:
- rat
- Strain:
- other: Albino
- Sex:
- not specified
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: own breeding facility
- Age at study initiation: 4 to 5 weeks
- Weight at study initiation: 90 to 120 g
- Fasting period before study: no
- Housing: no data
- Diet (e.g. ad libitum): Rockland rat diet, complete, ad libitum
- Water (e.g. ad libitum): ad libitum
Administration / exposure
- Route of administration:
- inhalation: vapour
- Type of inhalation exposure:
- whole body
- Vehicle:
- other: unchanged (no vehicle)
- Details on inhalation exposure:
- Test with graduate doses (standard test)
Test atmosphere was generated using a suitable proportioning pump by injecting definite amounts of test substance at a constant rate inside of a spirally corrugated surface of a minimally heated one inch Pyrex tube through which metered air is passed.
Inhalation hazard test
Test atmosphere was generated by passing a stream of dried air at 2.5 L/min at room temperature through a fritted glass disc immersed to a depth of at least 1 inch in approximately 50 mL of the test substance contained in a gas washing bottle. Six male or female albino rats were exposed for different exposure times to this atmosphere (flowing stream of air saturated or close to saturation with vapour). - Analytical verification of test atmosphere concentrations:
- no
- Duration of exposure:
- 4 h
- Remarks on duration:
- test with graduate doses
- Concentrations:
- Standard test
5000, 10000, and 20000 ppm ( 17.9, 35.8, and 71.6 mg/L), doses were spaced in a logarithmic series with a factor of 2.
For the inhalation hazard test, the test atmosphere was saturated or close to saturation with test substance vapor as indicated by the generation method of test atmosphere - No. of animals per sex per dose:
- six male or female animals per dose
- Control animals:
- not specified
- Details on study design:
- - Duration of observation period following administration: 14 days
- Frequency of observations and weighing: no data
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other: no data - Statistics:
- LC50 is calculated by the moving average method based on a 14-day observation period.
Results and discussion
Effect levels
- Sex:
- not specified
- Dose descriptor:
- LC50
- Effect level:
- 50.5 mg/L air (nominal)
- 95% CL:
- 39 - 65.5
- Exp. duration:
- 4 h
- Remarks on result:
- other: LC50 value calculated from the reported value of 14,100 ppm
- Mortality:
- Standard Test: Concentration Mortality
71.6 mg/L 6 / 6
35.8 mg/L 0 / 6
17.9 mg/L 0 / 6
Inhalation Hazard Tests: Maximum exposure time for no death: 10 min (LT50 = 14.1 min) - Clinical signs:
- other: 71.6 mg/L: loss of coordination by 4 min; poor coordination by 12 and prostrate by 60 min 35.8 mg/L: as above but prostrate at 2.5 h 17.9 mg/L: slight loss of coordination at 20 min
- Gross pathology:
- No special findings
Any other information on results incl. tables
Reported data (ppm) are converted to mg/L using a conversion factor of 3.58.
Applicant's summary and conclusion
- Interpretation of results:
- not classified
- Remarks:
- Migrated information Criteria used for interpretation of results: EU
- Conclusions:
- Exposure to 2-methylbutyraldehyde vapors in air at concentrations of 17.9, 35.8 and 71.6 mg/L for 4 hours resulted in the death of 0, 0 and 6 out of 6 animals respectively (observation period 14 days). From this data, a LC50 of ca. 50,5 mg/L is calculated.
- Executive summary:
For this acute inhalation toxicity study, a standard graduate dose test and an inhalation hazard test were performed. The observation period for both tests was 14 days.
Groups of six albino rats were exposed for 4 hours to graduate doses of 2-methylbutyraldehyde (2-methylbutanal) vapor in the breathing atmosphere of test animals. Doses were spaced in a logarithmic series with a factor of 2 (17.9, 35.8, and 71.6 mg/L).
In the inhalation hazard test, test animals were exposed for various time periods starting from several minutes up to 8 hours if appropriate (spacing factor of 2) to an atmosphere saturated or close to saturation with vapors of 2-methylbutyraldehyde. Actual atmosphere concentrations were not measured but can be estimated to be saturated or close to saturation by the method the atmosphere was generated.
In the standard test, concentrations of 5,000, 10,000 and 20,000 ppm (ca. 17.9, 35.8 and 71.6 mg/L) caused a mortality of 0, 0, and 6 out of 6 animals, respectively. From this data, a LC50 of 50.5 mg/L is calculated.
In the inhalation hazard test (saturated vapor), the exposure time was restricted to 10 min in order to produce no mortality (LT50 = 14.1 min).
The LC50 for 2-methylbutyraldehyde was determined to be 50,5 mg/L in rats (Carpenter 1974).
Standards of the OECD test guideline 403 (Acute Inhalation Toxicity) are only met with restrictions by this investigation (no concentrations and particle size distribution measured, only 6 rats used, sex not specified, reporting not according to test guideline). But the results are estimated to be sufficiently valid to assess the acute inhalation toxicity potential of 2-methylbutanal.
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