Isobutyraldehyde

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:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Range-finding toxicity data

Author:

Smyth H.F.

Year:

1954

Bibliographic source:

AMA Arch Ind Hyg Occup Med. 1954 Jul;10(1):61-8.

Reference 2

Reference Type:

publication

Title:

Unnamed

Year:

1991

Report date:

1991

Reference 3

Reference Type:

publication

Title:

Industrial hygiene and toxicology, Second Revised Edition, Volume II

Author:

Fassett D.W.

Year:

1962

Bibliographic source:

p. 1966-1978

Materials and methods

Principles of method if other than guideline:

Penetration of rabbit skin is estimated by a technique closely to the one-day cuff method of Draize and associates (Draize, J.H. et al.: J. Pharmacol. Exp. Therap. 82, 377, 1944), using groups of four male rabbits. The fur is removed from the entire trunk by clipping, and the dose is retained beneath an impervious plastic film. Animals were observed for 14 days.

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Isobutyraldehyde

EC Number:

201-149-6

EC Name:

Isobutyraldehyde

Cas Number:

78-84-2

Molecular formula:

C4H8O

IUPAC Name:

2-methylpropanal

Details on test material:

- Name of test material: isobutyraldehyde

Test animals

Species:

rabbit

Strain:

New Zealand White

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 3-5 months
- Weight at study initiation: average 2.5 – 3.5 kg
- Diet: Rockland rabbit ration

Administration / exposure

Type of coverage:

occlusive

Vehicle:

not specified

Details on dermal exposure:

Penetration of rabbit skin is estimated by a technique closely to the one-day cuff method of Draize and associates, using groups of four male rabbits weighing. The fur is removed from the entire trunk by clipping, and the dose is retained beneath an impervious plastic film. The animals are immobilized during the 24-hour contact period, after which the film is removed and the rabbits are caged for the subsequent 14-day observation period.

Duration of exposure:

24 h

Doses:

5, 10 mL/kg

No. of animals per sex per dose:

2 (low dose), 4 (high dose)

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days

Statistics:

Thompson's method was used for calculating the LD50.

Results and discussion

Effect levels

Effect levels 1

Sex:

male

Dose descriptor:

LD50

Effect level:

ca. 7.13 mL/kg bw

Based on:

test mat.

Remarks on result:

other: original value

Effect levels 2

Sex:

male

Dose descriptor:

LD50

Effect level:

5 583 mg/kg bw

Based on:

test mat.

Remarks on result:

other: density used for conversion: 0.783 g/cm3

Mortality:

Four animals dosed at 10 mL/kg died
The 2 animals dosed at 5 mL/kg survived.

Clinical signs:

other: erythema, edema and necrosis of the skin at the site of contact, with congestion and hemorrhage of the lungs in rabbits dying on study.