4-methylcyclohexanone

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1943

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Remarks:

Lack of substance identity information with respect to isomers. Non-standard repeated dosing. Inadequate follow up period.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1943

Materials and methods

Test guideline

Qualifier:

no guideline followed

Version / remarks:

no guideline followed

Principles of method if other than guideline:

The study reported toxicity following dermal exposure to meta and para-methylcyclohexanone isomers. For the dermal toxicity investigations, the liquid was administered by dropping a measured amount of the substance on the clipped skin area of a rabbit in multiple separate applications, until the desired dose was achieved over a period of hours. The skin was then washed.

GLP compliance:

no

Test type:

other: non-standard

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

4-methylcyclohexanone

EC Number:

209-665-3

EC Name:

4-methylcyclohexanone

Cas Number:

589-92-4

Molecular formula:

C7H12O

IUPAC Name:

4-methylcyclohexan-1-one

Constituent 2

Reference substance name:

3-methylcyclohexanone

EC Number:

209-710-7

EC Name:

3-methylcyclohexanone

Cas Number:

591-24-2

Molecular formula:

C7H12O

Test material form:

liquid

Details on test material:

- Density: 0.914
- Boiling point: 169-170.5°C
- Refractive index: 1.4458

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL:
Barrett Division of Allied Chemical and Dye Corporation.

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
Not reported.

Test animals

Species:

rabbit

Strain:

other: White

Sex:

not specified

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: local breeders
- Age at study initiation: young
- Weight at study initiation: not reported
- Fasting period before study: not reported
- Housing: not reported
- Diet (e.g. ad libitum): not reported
- Water (e.g. ad libitum): not reported
- Acclimation period: until observed to be healthy.

ENVIRONMENTAL CONDITIONS: Not reported.

Administration / exposure

Type of coverage:

open

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: 24 square inches
- Type of wrap if used: none

REMOVAL OF TEST SUBSTANCE
- Washing (if done): soap and water
- Time after start of exposure: 20min after last application

TEST MATERIAL
- Amount(s) applied: 5mL every 20min until the desired dose was achieved

Duration of exposure:

several hours

Doses:

15mL (4900mg/kg bw), 20mL (7200mg/kg bw), 35mL (13400mg/kg bw)

No. of animals per sex per dose:

one animal per dose (total of three)

Control animals:

no

Details on study design:

- Duration of observation period following administration: approximately four hours for the single surviving animal

Results and discussion

Effect levels

Key result

Sex:

not specified

Dose descriptor:

LDLo

Remarks:

lowest dose with mortality

Effect level:

7 200 mg/kg bw

Based on:

test mat.

Mortality:

Mortality was observed 2h 10min after dosing for both animals with 7200 and 13400 mg/kg bw dose levels.

Clinical signs:

other: After dermal application narcosis was induced with tremors and convulsive movements. Narcosis lasted for 2h for the one surviving animal.

Applicant's summary and conclusion

Interpretation of results:

study cannot be used for classification

Conclusions:

The lowest reported lethal dose was 7.2 grams/kg. An LD50 was not reported. The substance when dermally applied, produced hypothermia, narcosis and convulsive movements.

Executive summary:

Methylcyclohexanone was applied in 5 ml portions to the skin of 3 rabbits in 20 minutes intervals. The skin was washed 20 minutes after the last application. Doses of 4.9g/kg bw, 7.2g/kg bw and 13.4g/kg were applied. The substance produced hypothermia, narcosis and convulsive movements. Mortality was observed in the two highest doses, while the lowest dose animal recovered.