2-methylbutyraldehyde

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

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 (limited reporting on test substance and test performance)

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Unnamed

Year:

1974

Report date:

1974

Reference 2

Reference Type:

study report

Title:

Unnamed

Year:

1970

Report date:

1970

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

yes

Remarks:

: non fasted animals, limited reporting

GLP compliance:

no

Remarks:

pre-GLP study

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

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

Test animals

Species:

rat

Strain:

other: Carworth-Wistar

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: own breeding
- Age at study initiation: 4 to 5 weeks
- Weight at study initiation: 990 to 120 g
- Fasting period before study: no
- Housing: no data
- Diet (e.g. ad libitum): Rockland rat diet, complete

ENVIRONMENTAL CONDITIONS
- Temperature (°C): no data
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): no data

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

not specified

Details on oral exposure:

Whenever possible, the test substance was administered undiluted.

Doses:

4.0, 8.0, 16.0, and 32.0 mL/kg bw (3.2, 6.4, 12.9, and 25.7 g/kg bw)
Doses were arranged in a logarithnic series differing by a factor of two.

No. of animals per sex per dose:

5 (males)

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:

LD50 values were calculated by the method of Thompson (Thompson WR 1947, Bacteriol Rev 11, 115) using the Tables of Weil (Weil GS 1952, Biometrics 8, 249). The figures in parentheses show the limits of +/- 1.96 standard deviations.

Results and discussion

Effect levels

Sex:

male

Dose descriptor:

LD50

Effect level:

6 884 mg/kg bw

Remarks on result:

other: ± 1.96 standard deviations (4274 - 11086 mg/kg bw ); values are converted from mL/kg bw as reported by authors.

Mortality:

3200 mg/kg bw group 0/5
6400 mg/kg bw group 3/5
12900 mg/kg bw group 4/5
25700 mg/kg bw group 5/5

Clinical signs:

other: 12900 mg/kg bw group tremors and unsteady gait

Gross pathology:

congestion throughout the lungs and the abdominal viscera of the victims

Any other information on results incl. tables

The reported acute oral LD50 is 8.57 (5.32 - 13.8) mL/kg bw. The figures in parentheses show the limits of ± 1.96 standard deviations. Using a density of 0.8033 g/mL for 2 -methylbutyraldehyde, the LD 50 calculates to 6884 mg/kg bw (4274 - 11086 mg/kg bw).

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The acute oral LD50 of 2-methylbutyraldehyde is 6884 mg/kg bw in male rats. No classifcation is required according to EU legislation.

Executive summary:

The acute oral toxicity of 2-methylbutyraldehyde was determined in groups of 5 male Carworth-Wistar rats receiving the test material by oral gavage at doses of 3.2, 6.4, 12.9, and 25.7 g/kg bw. The observation period was 14 days. The LD50 and a range of ± 1.96 SD was calculated according to the method of Thomson (1947). Overall the study was conducted in accordance with the recently retracted OECD test guideline 401.

 

The acute oral LD50 was determined to be 6884 mg/kg bw in rats (Carpenter, 1974).