Cyclohexylbenzene

Skin irritation / corrosion

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: Well documented GLP study according to international guideline.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

adopted 17 July 1992

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Cyclohexylbenzene

EC Number:

212-572-0

EC Name:

Cyclohexylbenzene

Cas Number:

827-52-1

Molecular formula:

C12H16

IUPAC Name:

cyclohexylbenzene

Details on test material:

- Name of test material (as cited in study report): MCS-2805
- Lot No.: ABDR-016
- Description: clear colourless liquid
- Composition: cyclohexylbenzene: 92.6%; bicyclohexyl: 6.9%
- Date received: 2001-08-06
- Storage conditions: 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: David Percival Ltd, Moston, Sandbach, Cheshire, UK
- Age at study initiation: 12-16 weeks
- Weight at study initiation: 2.0-3.5 kg
- Housing: individually in suspended metal cages
- Diet: ad libitum (Certified Rabbit Diet (Code 5322) supplied by PMI Nutritional International, Nottingham, UK)
- Water: ad libitum
- Acclimation period: ≥ 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17-23°C
- Humidity (%): 30-70%
- Air changes (per hr): ≥ 15 days
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5 ml

Duration of treatment / exposure:

4 h

Observation period:

14 days

Number of animals:

3

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing: by gentle swabbing with cotton wool soaked in 74% industrial methylated spirits

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: 24, 48, 72 h

Score:

2

Reversibility:

fully reversible within: 14 days

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 24, 48, 72 h

Score:

2.2

Reversibility:

fully reversible within: 14 days

Any other information on results incl. tables

Erythema/eschar formation

Reading (hrs)	Individual scores - Rabbit number and sex
	11 Male	118 Male	119 Male
24	2	2	2
48	2	2	2
72	2	2	2
Mean score	2	2	2

Oedema formation

Reading (hrs)	Individual scores - Rabbit number and sex
	11 Male	118 Male	119 Male
24	2	3	2
48	2	3	2
72	2	2	2
	2.0	2.7	2.0

Applicant's summary and conclusion

Conclusions:

The test material produced a primary irritation index of 4.2.

Executive summary:

The study was performed to assess the irritancy potential of the test material to the skin of the New Zealand White rabbit.

A single 4 -h, semi-occluded application of the test material to the intact skin of 3 rabbits produced well-defined erythema and slight to moderate oedema. Other skin reactions noted were oedema extending ventrally below treatment site, loss of skin elasticity, severe desquamation, reduced regrowth of fur and crust formation, which prevented evaluation of erythema and oedema. No corrosive effects were noted.

The test material produced a primary irritation index of 4.2.