Methylcyclohexane

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study with acceptable restrictions. Lack of details on test material (analytical purity).

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1982

Report date:

1982

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

yes

Remarks:

lack of details on test material (analytical purity)

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Methylcyclohexane

EC Number:

203-624-3

EC Name:

Methylcyclohexane

Cas Number:

108-87-2

Molecular formula:

C7H14

IUPAC Name:

methylcyclohexane

Details on test material:

- Name of test material (as cited in study report): methyl cyclohexane
- Substance type: technical product
- Physical state: liquid
- Analytical purity: no data

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Laboratory Animals, Inc.
- Age at study initiation: adult
- Housing: individual
- Diet: Purina Lab Rabbit Chow®, ad libitum. Feed was periodically analyzed for concentrations of specified heavy metals, antibiotics, aflatoxin, pesticides, and nitrosamines
- Water: Tap water, ad libitum. The water was routinely analyzed on a retrospective basis for specified microorganisms, pesticides, heavy metals, alkalinity, and halogens.
- Quarantine: Minimum of 1 week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 ± 2
- Humidity (%): 40-60
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Vehicle:

unchanged (no vehicle)

Controls:

other: the untreated eye served as control

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.1 mL

Duration of treatment / exposure:

Single instillation without washing

Observation period (in vivo):

7 days
Reading time points: 1, 24, 48, and 72 h, and at 4 and 7 days

Number of animals or in vitro replicates:

3 males and 3 females

Details on study design:

SCORING SYSTEM: Draize scoring system

TOOL USED TO ASSESS SCORE: fluorescein

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

out of all 6 animals

Time point:

other: mean over 24, 48 and 72 h

Score:

0

Max. score:

4

Reversibility:

other: reversibility: not applicable

Results 2

Irritation parameter:

iris score

Basis:

mean

Remarks:

out of all 6 animals

Time point:

other: mean over 24, 48 and 72 h

Score:

0

Max. score:

2

Reversibility:

other: reversibility: not applicable

Results 3

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

out of animals #1-3 and #5, #6

Time point:

other: mean over 24, 48 and 72 h

Score:

0

Max. score:

3

Reversibility:

other: reversibility: not applicable

Results 4

Irritation parameter:

conjunctivae score

Basis:

animal #4

Time point:

other: mean over 24, 48 and 72 h

Score:

0.3

Max. score:

3

Reversibility:

fully reversible within: 48 hours

Results 5

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

over all 6 animals

Time point:

other: mean over 24, 48 and 72 h

Score:

0

Max. score:

4

Reversibility:

other: reversibility: not applicable

Irritant / corrosive response data:

1 h post-instillation: conjuctival redness (vessels injected above normal) was noted in 4/6 rabbits as only eye effect.
24 h post-instillation: conjuctival redness (vessels injected above normal) was noted in 1/6 rabbits as only eye effect.
48 h to 7 days: No corneal opacity, iritis, conjunctival redness, chemosis or discharge were observed.

Other effects:

No further local or systemic effects were reported.

Any other information on results incl. tables

Table 1: Evaluation of the eye reaction

Rabbit No. / sex	Scoring [h]	Cornea	Iris	Conjunctiva
				Redness	Chemosis
#1 / m	1	0	0	0	0
	24	0	0	0	0
	48	0	0	0	0
	72	0	0	0	0
Mean (24, 48, 72 h)		0	0	0	0
#2 / m	1	0	0	1	0
	24	0	0	0	0
	48	0	0	0	0
	72	0	0	0	0
Mean (24, 48, 72 h)		0	0	0	0
#3 / m	1	0	0	1	0
	24	0	0	0	0
	48	0	0	0	0
	72	0	0	0	0
Mean (24, 48, 72 h)		0	0	0	0
#4 / f	1	0	0	1	0
	24	0	0	1	0
	48	0	0	0	0
	72	0	0	0	0
Mean (24, 48, 72 h)		0	0	0.33	0
#5 / f	1	0	0	0	0
	24	0	0	0	0
	48	0	0	0	0
	72	0	0	0	0
Mean (24, 48, 72 h)		0	0	0	0
#6 / f	1	0	0	1	0
	24	0	0	0	0
	48	0	0	0	0
	72	0	0	0	0
Mean (24, 48, 72 h)		0	0	0	0

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Methylcyclohexane was tested for primary eye irritation in 3 male and 3 female rabbits in a study following a protocol similar to OECD guideline 405. The test material (0.1 mL) was applied into the conjunctival sac of one eye, the other eye serving as control. The eyes were examined and scored 1, 24, 48 and 72 h as well as 4 and 7 days after application. No corneal opacity, iritis or chemosis were observed in any animal at any reading time point (all scores 0.0). Slight conjunctival redness was seen in 4/6 rabbits 1 h post-application, which persisted in only 1/6 animals at the 24 h reading. No conjunctival redness was observed at the following scoring time points. The mean conjunctivae score over 24, 48 and 72 h was 0.3 for this animal and 0.0 for the remaining 5 animals.

In this study, no corneal opacity, iritis or chemosis and only slight and transient conjunctival redness were observed in rabbit eyes treated with methylcyclohexane; the effects being fully reversible within 24-48 h post-instillation. Therefore, the study results do not fulfil the classification criteria for eye irritation according to Regulation (EC) 1272/2008 and Directive 67/548/EEC.

CLP: not classified
DSD: not classified