1-Methyl-4-[(trans,trans)-4'-propyl[1,1'-bicyclohexyl]-4-yl] -benzene

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

May 25, 2000 - Jun 01, 2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

(trans(trans))-4'-vinyl-4-(4-methylphenyl)bicyclohexyl

EC Number:

439-730-3

EC Name:

(trans(trans))-4'-vinyl-4-(4-methylphenyl)bicyclohexyl

Cas Number:

155041-85-3

Molecular formula:

Hill formula: C21H30 CAS formula: C21H30

IUPAC Name:

(trans(trans))-4'-Vinyl-4-(4-methylphenyl)bicyclohexyl

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Wiga GmbH
- Age at study initiation: about 33 weeks
- Weight at study initiation: 4,31 kg (3,77-4,76)
- Housing: separately
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Temperature: 20 - 22 °C
- Humidity: 50 to 64 %
- Air changes: not specified
- Photoperiod: 12 / 12 hrs dark / hrs light

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

water

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5 g

Duration of treatment / exposure:

4 hours

Observation period:

24, 48, 72 hours after removal of patches

Number of animals:

3 female rabbits

Details on study design:

TEST SITE
- Area of exposure: back
- Type of wrap if used: semi-occlusive

REMOVAL OF TEST SUBSTANCE
- Washing: yes
- Time after start of exposure: 4 h

OBSERVATION TIME POINTS :
1 h after removal of the test item and then daily for further 7 days.

SCORING SYSTEM:
- Method of calculation: according to the guideline and Draize:
Grading scale for evaluation:
Erythema and eschar formation Scores
No erythema 0
Very slight erythema (barely perceptible) 1
Well defined erythema 2
Moderate to severe erythema 3
Severe erythema to eschar formation preventing grading of erythema 4

Maximum possible: 4

Edema formation Scores
No edema 0
Very slight edema (barely perceptible) 1
Slight edema (edges of area well defined by definite raising) 2
Moderate edema (raised approx. 1 mm) 3
Severe edema (raised more than 1 mm and extending beyond area of exposure) 4

Maximum possible: 4

Total possible irritation score (maximum): 8

Mean score = Mean grading for erythema or edema of all the rabbits per time point
Mean cumulative score = Mean grading of all readings for erythema and edema per time point
Mean score per animal = Mean grading for each animal of erythema or edema (24, 48, and 72 hours after removal of the patches)

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 3

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 4

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 5

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 6

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritant / corrosive response data:

After a single application to the intact dorsal skin of rabbits, for a 4 hours period of exposure under semiocclusive conditions, no signs of irritation were observed in the treated areas.

Other effects:

None

Any other information on results incl. tables

Clinical findings

After a single application to the intact dorsal skin of rabbits, for a 4 hours period of exposure under semiocclusive conditions, no signs of irritation were observed in the treated areas. No signs of clinical toxicity were detected.

Mortality

All animals survived the observation period.

Body weight

Body weight development of the treated rabbits was inconspicuous.

Table 1 Individual findings

	Mean score (24, 48, 72 h)			Maximum value (24, 48, 72 h)
Animal No	4	6	10	4	6	10
Erythema	0 00	000	0.00	0	0	0
Edema	0.00	000	0.00	0	0	0

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test item was not irritating to the skin in this assay.

Executive summary:

The purpose of this assay was to identify the skin irritation/corrosion potential of the test item when applied to the intact skin of previously shaven rabbits for a 4 hours period under semiocclusive conditions. This study should provide a rational basis for risk assessment to the irritating potential of the test item in man. To test for primary skin irritation, the test item was mixed with some drops of Aqua pro injectione to ensure good contact to the skin. Afterwards the test material was spread onto patches and applied to the intact skin of three previously shaven rabbits for a 4 hours period under semiocclusive conditions. The first examination of the treated skin sites followed 1 hour after removal of the patches. Then, examinations were performed daily for further 7 days. Under the conditions of the present study no signs of irritation were seen. The evaluation of all animals yields a zero mean score. The test item was not irritating to the skin in this assay.