Cyclohexane

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study, GLP status unclear, acceptable for assessment

Data source

Reference

Reference Type:

publication

Title:

Evaluation of the test method for skin irritation as prescribed by OECD and EEC

Author:

Jacobs G and Martens M

Year:

1987

Bibliographic source:

J. Toxicol.-Cut. & Ocular Toxicol. 6(3), 215-225

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Principles of method if other than guideline:

Cyclohexane was applied to shaved rabbit skin and erythema and oedema recorded (using Draize criteria) at 1, 24, 48, and 72 hr after removal of the patch. Observations continued thereafter every 2 days until dermal responses had resolved in at least one rabbit.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Cyclohexane

EC Number:

203-806-2

EC Name:

Cyclohexane

Cas Number:

110-82-7

Molecular formula:

C6H12

IUPAC Name:

cyclohexane

Details on test material:

- Name of test material (as cited in study report): cyclohexane
- Lot/batch No.: 3100
- Supplier: Merck, Brussels, Belgium
- Purity: no further details

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Proefstations voor Veeteelt (Merelbeke, Belgium)
- Age at study initiation: 9-24 weeks
- Weight at study initiation: 2.75-5.2 kg
- Housing: individual mesh wire bottom cages
- Diet: Conventional Laboratory diet ad libitum
- Water: Tap-water ad libitum
- Acclimatisation period: At least 7 days
- Normal housing conditions

Test system

Type of coverage:

occlusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.5 mL

Duration of treatment / exposure:

4 hours, occluded

Observation period:

Animals examined for signs of erythema and oedema formation at 1, 24, 48 and 72 hr after removal of the test patch

Number of animals:

5 or 6 (not specified)

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Remarks:

for all animals, all timepoints

Time point:

24/48/72 h

Score:

1.93

Remarks on result:

other: time course information not available

Results 2

Irritation parameter:

erythema score

Basis:

mean

Remarks:

maximum erythema score (Smax)

Time point:

other: 119 h (time of Smax)

Score:

2.56

Results 3

Irritation parameter:

edema score

Basis:

mean

Remarks:

for all animals, all timepoints

Time point:

24/48/72 h

Score:

0

Applicant's summary and conclusion

Interpretation of results:

not irritating

Conclusions:

Cyclohexane caused erythema (overall mean 1.93) when applied to shaved rabbit skin under occlusion for 4 hr. The magnitude of the response was below the threshold for classification.

Executive summary:

The skin irritation potential of cyclohexane toward shaved rabbit skin was evaluated according to Annex V of directive 67/548 EEC. The sample (0.5 mL) was applied under occlusion for 4 hr with an area of untreated skin serving as control. The overall mean score for erythema (all animals over all times points) was 1.93; no oedema was reported. The results indicate that cyclohexane is not irritating to rabbit skin.