Isobutyl acetate

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

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 (only 4 animals per group, occlusive wrapping, limited reporting)

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1962

Report date:

1962

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

yes

Remarks:

: only 4 animals per group, occlusive wrapping, limited reporting

Principles of method if other than guideline:

Pre-guideline test, but method similar to OECD TG 402

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:

Isobutyl acetate

EC Number:

203-745-1

EC Name:

Isobutyl acetate

Cas Number:

110-19-0

Molecular formula:

C6H12O2

IUPAC Name:

isobutyl acetate

Details on test material:

- Name of test material (as cited in study report): Acetic acid, isobutyl ester
- no further information on test material
- Analytical purity: no data, but as iso-butyl acetate is usually available as high quality / purity, it can probably be assumed that test item purity was high

Test animals

Species:

rabbit

Strain:

New Zealand White

Sex:

male

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: 2.5 - 3.5 kg

Administration / exposure

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: part of the trunk
- % coverage: no data
- Type of wrap if used: impervious plastic film
- Restraining of animals: animals are immobilized during the 24 h exposure period

REMOVAL OF TEST SUBSTANCE
- Washing (if done): no data
- Time after start of exposure: 24 hours

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): graduate doses were applied, but individual doses are not specified

Duration of exposure:

24 hours

Doses:

no individual doses specified

No. of animals per sex per dose:

4

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: no data
- Necropsy of survivors performed: no data
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other: no data

Statistics:

LD50 values were calculated by the method of Thompson (1947, Bacteriol. Rev. 11, 115) using the tables of Weil (1952, Biometrics 8, 249. The limits of ± 1.96 standard deviations are presented.

Results and discussion

Effect levels

Sex:

male

Dose descriptor:

LD50

Effect level:

> 17 400 mg/kg bw

Remarks on result:

other: The reported value is > 20 mL/kg bw. This is the highest dose which could technically be administered

Mortality:

no data

Any other information on results incl. tables

The acute dermal LD50 is reported as > 20 mL/kg bw. Using a density of 0.871 g/mL (Sect. 4.4), the LD50 calculates to > 17400 mg/kg bw.

 

There is no information on local effects reported.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The acute dermal LD50 for isobutyl acetate was determined to be > 17400 mg/kg bw in male rabbits.

Executive summary:

The acute dermal toxicity of isobutyl acetate was determined in groups of 4 male albino New Zealand rabbits receiving graduate single doses of test substance per group. Number and quantity of individual doses are not specified. The exposure time was 24 hours followed by an observation period of 14 days. From mortality data, the LD50 and a range of ± 1.96 SD was calculated according to the method of Thomson (1947).

Overall, the study was conducted similar to OECD test guideline 402 with some restrictions (only 4 animals per group, occlusive wrapping, limited reporting).

The acute dermal LD50 for isobutyl acetate was > 17400 mg/kg bw (calculated from reported value of > 20 mL/kg bw and using a density of 0.871 mg/mL) in rabbits (Smyth, 1962).