(1-methylethyl)-1,1'-biphenyl

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study according to national standard, acceptable for assessment, but does not meet important criteria of today standard methods (see below under Principles)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1975

Report date:

1975

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Code of Federal Regulations - 16 CFR 1500.41

Deviations:

no

Principles of method if other than guideline:

Overstringent test conditons, but evaluable in this case.
Shortcomings of the study design: cover of exposure site occlusive, exposure 24 h, observation time 72 h, number of readings 2, limited reporting

GLP compliance:

no

Remarks:

pre-GLP study

Test material

Test material information

Constituent 1

Reference substance name:

(1-methylethyl)-1,1'-biphenyl

EC Number:

247-156-8

EC Name:

(1-methylethyl)-1,1'-biphenyl

Cas Number:

25640-78-2

Molecular formula:

C15H16

IUPAC Name:

(1-methylethyl)-1,1'-biphenyl

Details on test material:

- Name of test material (as cited in study report): X489-17B
- no further information

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 2.0 to 2.5 kg
- Housing: individually
- animals were maintained in accordance with standard laboratory procedure

Test system

Type of coverage:

occlusive

Preparation of test site:

other: two exposure areas at the trunk of the animals, one area clipped free of hair and one area clipped and abraded

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL neat test substance

Duration of treatment / exposure:

24 hours (animals were kept immobilised in an animal holder)

Observation period:

48 hours (after end of treatment)

Number of animals:

6

Details on study design:

TEST SITE
- Area of exposure: one square inch (6.25 cm²); 2 sites on each animal (abraded and nonabraded skin)
- Type of wrap if used: gauze patch held in place with Dermicel tape; during the 24h exposure period, the trunks of the test animals were wrapped with rubberised cloth

REMOVAL OF TEST SUBSTANCE
- Washing (if done): no data

SCORING SYSTEM
- according to Draize (equivalent to Table 1 of OECD TG 404: 1981)

Results and discussion

In vivo

Results

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: 0 and 48 h after patch removal

Score:

2.5

Max. score:

8

Reversibility:

no data

Any other information on results incl. tables

Skin reaction scores from nonabraded skin at the end of exposure period/patch removal (time 0) and 48 h after patch removal

 

Animal Number	Erythema and Eschar Formation			Oedema Formation
	0 h	48 h	mean	0 h	48 h	mean
1	1	2	1.5	2	1	1.5
2	1	2	1.5	2	1	1.5
3	1	1	1	1	1	1
4	1	1	1	1	1	1
5	1	1	1	2	1	1.5
6	1	1	1	1	1	1

 

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

With regard to the stringency of exposure conditions (24 h, occlusive) and only slight to moderate irritation response (scores <= 2), it is concluded that the irritating potency of isopropylbiphenyl is low and does not meet the classification requirements of Regulation (EC) No 1272/2008 on classification, labelling and packaging of substances and mixtures.