Benzene, 1,4-bis(1-methylethyl)-, homopolymer

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2002-08-19 to 2002-08-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and guideline compliant

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

(1992)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

(1992)

Deviations:

no

GLP compliance:

yes

Remarks:

statement

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

449-400-0

EC Name:

-

Cas Number:

25822-43-9

Molecular formula:

C24H34

IUPAC Name:

1,1'-(2,3-dimethylbutane-2,3-diyl)bis[4-(propan-2-yl)benzene]

Test material form:

other: solid, fine scales

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland GmbH, D-97633 Sulzfeld.
- Weight at study initiation: 1.9- 2.0 kg
- Housing: Individual caging in metal wire cages Ehret GmbH, D-79312 Emmendingen, 79 cm x 59 cm bottom area, 38 cm height, with a wooden rest shelf, 15 cm x 59 cm.
- Diet: Altromin 2023 diet. Hay-briquettes (supplied by SSNIFF, D-59494 Soest) were offered additionally as a dietary supplement.
- Water: Tap water from an automatic watering system
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 19.7 °C
- Humidity: 72.2 %
- Air changes: 12 per hour
- Photoperiod: artificial light from 6 a.m. to 6 p.m.

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

water

Controls:

not required

Amount / concentration applied:

0.5 g test item, ground in a mortar and moistened with deionised water.

Duration of treatment / exposure:

4 h

Observation period:

The treated areas and the surrounding untreated skin (control area) of the animals were examined for erythema/ eschar and oedema as well as for other local alterations approximately 1, 24, 48 and 72 hours after patch removal.

Number of animals:

3 females

Details on study design:

TEST SITE
- Area of exposure: median on the dorsal thoracal region
- % coverage: 2.5 cm x 2.5 cm
- Type of wrap if used: semi-occlusive by a dressing: Self adhesive non woven fabric, hypoallergenic, made by Beiersdorf AG, D-20245 Hamburg.

REMOVAL OF TEST SUBSTANCE
- removal was performed immediately after 4 hour exposure with Kleenex-tissues.

SCORING SYSTEM:
Erythema / Eschar formation
0 = No erythema.
1 = Very slight erythema (barely perceptible).
2 = Well-defined erythema.
3 = Moderate to severe erythema.
4 = Severe erythema (beet redness) or eschar formation (injuries in depth).

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

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

edema score

Basis:

animal #1

Remarks:

(mean score 1)

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

4

Results 2

Irritation parameter:

edema score

Basis:

animal #2

Remarks:

(mean score 2)

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

4

Results 3

Irritation parameter:

edema score

Basis:

animal #3

Remarks:

(mean score 3)

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

4

Results 4

Irritation parameter:

erythema score

Basis:

animal #1

Remarks:

(mean score 1)

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

4

Results 5

Irritation parameter:

erythema score

Basis:

animal #2

Remarks:

(mean score 2)

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

4

Results 6

Irritation parameter:

erythema score

Basis:

animal #3

Remarks:

(mean score 3)

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

4

Other effects:

None

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Based on the results of the skin irritation study the test item is not subjected to classification and labelling for skin irritation/ corrosion effects according to Directive 67/548/EEC and Regulation (EC) No 1272/2008 (CLP).

Executive summary:

The aim of the study was to investigate the irritation/ corrosion potential of the test item following a single application onto intakt skin of rabbits. The study was performed in accordance with the OECD 404, adopted in 1992. 500 mg of the test item were applied via a patch to a site of 2.5 cm x 2.5 cm and covered by a semi-occlusive dressing. After 4 hours the test item was removed and clinical signs of toxicity and skin reaction were observed after 1, 24, 48 and 72 hours. No toxic effects of the test item were observed. The mean score (edema or erythema) that each animal obtained was 0. Therefore, under the selected test conditions, the test item is considered to be "not irritating" to skin.