2,2'-methylenebis[6-cyclohexyl-p-cresol]

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: see 'Remark'

Remarks:

Conducted prior to GLP implementation similar to OECD 404 on the registered substance itself with some deficiencies in documentation and performance, i.e. only two animals were used instead of three, substance was applied on the ear, not the trunk, evaluation criteria not defined.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1979

Report date:

1979

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

not applicable

GLP compliance:

no

Remarks:

test conducted prior to GLP implementation

Test material

Test material information

Constituent 1

Reference substance name:

2,2'-methylenebis[6-cyclohexyl-p-cresol]

EC Number:

223-773-8

EC Name:

2,2'-methylenebis[6-cyclohexyl-p-cresol]

Cas Number:

4066-02-8

Molecular formula:

C27H36O2

IUPAC Name:

2-cyclohexyl-6-[(3-cyclohexyl-2-hydroxy-5-methylphenyl)methyl]-4-methylphenol

Test material form:

not specified

Details on test material:

- Substance type: pure substance

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Housing: individually

Test system

Type of coverage:

semiocclusive

Preparation of test site:

not specified

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 500 mg

Duration of treatment / exposure:

24 h

Observation period:

7 days

Number of animals:

2

Details on study design:

TEST SITE
- Area of exposure: inner face of the ear
- Type of wrap if used: band aid

REMOVAL OF TEST SUBSTANCE
- Washing (if done): with water and soap/vegetable oil
- Time after start of exposure: 24 h

Results and discussion

In vivo

Results

Irritation parameter:

other: irritating properties

Basis:

mean

Remarks on result:

other: not irritating

Applicant's summary and conclusion

Interpretation of results:

not irritating

Conclusions:

The study was conducted prior to GLP implementation similar to OECD 404 on the registered substance itself with some deficiencies in documentation and performance. Nevertheless, with the given properties of the test item, the methodological deficiencies are unlikely to have any influence on the results. The given information on test performance allows the conclusion that the method was scientifically reasonable performed. Also, the result (not irritating) is confirmed by the other available studies on skin and in vivo eye irritation, clearing any doubts regarding the reliability of the result. Hence, Phenol, 2,2'-methylenebis-(6-cyclohexyl-4-methyl) does not need to be regarded as dermal irritant.

Executive summary:

In a primary dermal irritation study similar to OECD 404, two New Zealand White rabbits were dermally exposed to 500 mg of unchanged Phenol, 2,2'-methylenebis-(6-cyclohexyl-4-methyl) for 24 hours to the inner side of the ear.  Animals then were observed for 7 days. In this study, Phenol, 2,2'-methylenebis-(6-cyclohexyl-4-methyl) is not a dermal irritant.