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Diss Factsheets

Toxicological information

Skin irritation / corrosion

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Administrative data

Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study conducted according to GLP and guideline

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1991
Report date:
1991

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)
Qualifier:
according to guideline
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
GLP compliance:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
1,1'-(1,1-dimethyl-3-methylene-1,3-propanediyl)bisbenzene
EC Number:
228-846-8
EC Name:
1,1'-(1,1-dimethyl-3-methylene-1,3-propanediyl)bisbenzene
Cas Number:
6362-80-7
Molecular formula:
C18H20
IUPAC Name:
(4-methyl-4-phenylpent-1-en-2-yl)benzene
Details on test material:
- Physical state: Liquid
- Analytical purity: 2,4-dIphenyl-4-methyl-1-pentene 92% min; 2,4-dIphenyl-4-methyl-2-pentene 5% max
- Lot/batch No.: 1102
- Storage condition of test material: Room temperature in the dark

Test animals

Species:
rabbit
Strain:
New Zealand White
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Ranch Rabbits Ltd., Crawley Down, Sussex, England
- Age at study initiation: Approximately 11 to 13 weeks
- Weight at study initiation: 2.6 to 2.9 kg
- Housing: Housed individually in metal cages with perforated floors
- Diet: SDS Stanrab (P) rabbit diet ad libitum
- Water: ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature: 19°C
- Humidity: 30-70 %
- Air changes: Approximately 19 per hr
- Photoperiod: 12 hours artificial light (0700 - 1900 hours) in each 24 hour period

Test system

Type of coverage:
semiocclusive
Preparation of test site:
shaved
Vehicle:
unchanged (no vehicle)
Controls:
no
Amount / concentration applied:
0.5 ml
Duration of treatment / exposure:
4 h
Observation period:
14 days
Number of animals:
3
Details on study design:
TEST SITE
- Area of exposure: Dorso-lumbar region
- Type of wrap if used: Elastoplast elastic adhesive dressing

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Washed with water
- Time after start of exposure: 4 hr

SCORING SYSTEM: Grading and scoring of dermal reactions were performed using the prescribed numerical scoring system as follows:

Erythema and eschar formation:

No erythema 0
Very slight erythema (barely perceptible) 1
Well defined erythema 2
Moderate to severe erythema 3
Severe erythema (beet redness) to slight
eschar formation (injuries in depth) 4

Oedema formation:

No oedema 0
Very slight oedema (barely perceptible) 1
Slight oedema (edges of area well defined by
definitive raising) 2
Moderate oedema (raised approximately 1 millimetre) 3
Severe oedema (raised more than 1 millimetere
and extending beyond the area of exposure) 4

Any other lesion not covered by this scoring system, was described


Results and discussion

In vivo

Resultsopen allclose all
Irritation parameter:
erythema score
Basis:
animal #1
Time point:
24/48/72 h
Score:
2
Max. score:
4
Reversibility:
fully reversible within: 14 days
Irritation parameter:
erythema score
Basis:
animal #2
Time point:
24/48/72 h
Score:
2
Max. score:
4
Reversibility:
fully reversible within: 14 days
Irritation parameter:
erythema score
Basis:
animal #3
Time point:
24/48/72 h
Score:
2
Max. score:
4
Remarks on result:
other: Necrosis observed on day 4, but was ameliorated by day 9
Irritation parameter:
edema score
Basis:
animal #1
Time point:
24/48/72 h
Score:
1
Max. score:
4
Reversibility:
fully reversible within: 10 days
Irritation parameter:
edema score
Basis:
animal #2
Time point:
24/48/72 h
Score:
1
Max. score:
4
Reversibility:
fully reversible within: 11 days
Irritation parameter:
edema score
Basis:
animal #3
Time point:
24/48/72 h
Score:
1
Max. score:
4
Reversibility:
fully reversible within: 10 days
Irritant / corrosive response data:
The numerical scores awared to the dermal reactions are given in table 1.

Well defined erythema with slight oedema was evident at all three treatment sites following the removal of the dressings (day 1)

Similar reactions persisted for a further 5 or 7 days before regressing in two animals, but progressed in the remaining animal by day 4 into necrotic foci with very slight or slight oedema.

Reactions ameliorated at all sites by days 7 or 9 with very slight erythema and oedema present. A similar level of response (with or without very slight oedema) persisted, but resolved by day 14.

Desquamation of the stratum corneum (sloughing) was seen in all animals by days 6/9 and was still visible at all sites on day 14.

Any other information on results incl. tables

Table 1: Dermal reactions elicited by the test substance

Rabbit number and sex

E=erythema

O=oedema

Day

1*

2

3

4

5

6

7

8

9

10

11

12

13

14

866♀

E

O

2

1

2

1

2

1

2

1

2

1

2B

1

1B

1

1B

1

1B

1

1B

0

1B

0

1B

0

1B

0

0B

0

867♀

E

O

2

1

2

1

2

1

2

1

2

1

2B

1

2B

1

2B

1

1B

1

1B

1

1B

0

1B

0

1B

0

0B

0

868♀

E

O

2

1

2

1

2

1

4A

2

4A

2

4A

1

4A

1

4A

1

1B

1

1B

0

1B

0

1B

0

1B

0

0B

0

* Approximately 30 minutes after removal of the dressing

A Necrosis

B Sloughing

Applicant's summary and conclusion

Interpretation of results:
other: not classified as irritating to skin under CLP
Conclusions:
The test substance is not considered to be irritating to skin according to CLP Regulation (EC) no. 1272/2008