Thymol

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

MAR - AUG 1986

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1986

Report date:

1986

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

12 MAY 1981

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Version / remarks:

19 SEP 1984

Deviations:

no

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Thymol

EC Number:

201-944-8

EC Name:

Thymol

Cas Number:

89-83-8

Molecular formula:

C10H14O

IUPAC Name:

5-methyl-2-(propan-2-yl)phenol

Test material form:

solid: crystalline

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Interfauna UK ltd.
- Weight at study initiation: 3.1 - 3.7 kg
- Housing: single caged (type III cage)
- Diet (e.g. ad libitum): ad libitum (ssniff K 4, Versuchstierdiäten GmbH, Soest/Westfalen)
- Water (e.g. ad libitum): ad libitum (tap water)
- Acclimation period: 14 d

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 (+/- 2)
- Humidity (%): 45 - 65
- Air changes (per hr): 10
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

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

Duration of treatment / exposure:

24 hour(s)

Observation period (in vivo):

21 days

Number of animals or in vitro replicates:

3

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Yes, with physiological NaCl solution
- Time after start of exposure: 24 h

SCORING SYSTEM: Draize

TOOL USED TO ASSESS SCORE: fluorescein, UV light

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

animal #1

Remarks:

F84

Time point:

24/48/72 h

Score:

2.7

Max. score:

4

Reversibility:

fully reversible within: 14 d

Results 2

Irritation parameter:

iris score

Basis:

animal #1

Remarks:

F84

Time point:

24/48/72 h

Score:

1

Max. score:

2

Reversibility:

fully reversible within: 14 d

Results 3

Irritation parameter:

conjunctivae score

Basis:

animal #1

Remarks:

F84

Time point:

24/48/72 h

Score:

2.3

Max. score:

3

Reversibility:

fully reversible within: 14 d

Results 4

Irritation parameter:

chemosis score

Basis:

animal #1

Remarks:

F84

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 21 d

Results 5

Irritation parameter:

cornea opacity score

Basis:

animal #2

Remarks:

D87

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 21 d

Results 6

Irritation parameter:

iris score

Basis:

animal #2

Remarks:

D87

Time point:

24/48/72 h

Score:

1

Max. score:

2

Reversibility:

not fully reversible within: 21 d

Results 7

Irritation parameter:

conjunctivae score

Basis:

animal #2

Remarks:

D87

Time point:

24/48/72 h

Score:

2.3

Max. score:

3

Reversibility:

not fully reversible within: 21 d

Results 8

Irritation parameter:

chemosis score

Basis:

animal #2

Remarks:

D87

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 21 d

Results 9

Irritation parameter:

cornea opacity score

Basis:

animal #3

Remarks:

D86

Time point:

24/48/72 h

Score:

1.3

Max. score:

4

Reversibility:

not fully reversible within: 21 d

Results 10

Irritation parameter:

iris score

Basis:

animal #3

Remarks:

D86

Time point:

24/48/72 h

Score:

1

Max. score:

2

Reversibility:

fully reversible within: 21 d

Results 11

Irritation parameter:

conjunctivae score

Basis:

animal #3

Remarks:

D86

Time point:

24/48/72 h

Score:

2.3

Max. score:

3

Reversibility:

fully reversible within: 14 d

Results 12

Irritation parameter:

chemosis score

Basis:

animal #3

Remarks:

D86

Time point:

24/48/72 h

Score:

2.3

Max. score:

4

Reversibility:

fully reversible within: 21 d

Irritant / corrosive response data:

A positive fluorescein test was shown up to the 21st day of follow-up. Rabbits D87 and D86 showed a pannus effect from the 14th day of follow-up. In rabbit D86 there was swelling in the lower area of ​​the globe from the 14th day of observation.

Applicant's summary and conclusion

Interpretation of results:

Category 1 (irreversible effects on the eye) based on GHS criteria

Remarks:

EU GHS

Conclusions:

Based on the results of this study the test item is assessed as 'irreversible effects on the eye', as the effects were irreversible in one out of three animals.

Executive summary:

The test item was tested for eye irritation in a study according to OECD TG 405. Three rabbits received a dose of 100 µL/animal in the conjunctival sac of the eye. After 24 h the eye was washed. The eyes were examined for a postexposure period of 21 days. As a result, the test item induced eye damage, as the effects were irreversible in one out of three animals.