Registration Dossier

Administrative data

Endpoint:
eye irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Non-GLP, available as unpublished report, near guideline study, minor restrictions in design and/or reporting but otherwise adequate for assessment

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1980
Report Date:
1980

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): 2-methyl-2-butene
- Physical state: Strong smelling, colourless liquid with a specific gravity of 0.66
- Stability under test conditions: stable for duration of experiment, expiry date 1 January 1981
- Storage condition of test material: in fridge

Test animals / tissue source

Species:
rabbit
Strain:
New Zealand White
Details on test animals or tissues and environmental conditions:
TEST ANIMALS
- Source: Shell Toxicology Laboratory, Breeding Unit, Tunstall, UK
- Age at study initiation: 4-6 months
- Weight at study initiation: 2982-4208 g males, 3930-4915 g males
- Housing: Individually in hanging stainless steel cages with all mesh floors and tops and half mesh fronts (58 x 43 x 43 cm)
- Diet: SG1 with vitamin C supplement (Grain Harvesters Ltd) ad libitum.
- Water: Filtered public water ad libitum.
- Acclimation period: 14 days

ENVIRONMENTAL CONDITIONS
- Temperature: 16-19 °C

IN-LIFE DATES: From: 7 May 1980 To: 18 July 1980

Test system

Vehicle:
unchanged (no vehicle)
Controls:
no
Amount / concentration applied:
TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.2 mL
Observation period (in vivo):
7 days
Number of animals or in vitro replicates:
6
Details on study design:
REMOVAL OF TEST SUBSTANCE
- Washing: No

SCORING SYSTEM: Initial pain scored on a 1-6 scale. Eye irritation scored according to the Draize scale. Mean total scores transcribed to a grade and descriptive rating using a modification of the Kay and Calandra technique.

TOOL USED TO ASSESS SCORE: fluorescein

Results and discussion

In vivo

Resultsopen allclose all
Irritation parameter:
conjunctivae score
Basis:
mean
Time point:
other: 1 hour, 1, 2, 3 and 7 days
Score:
0.5
Irritation parameter:
cornea opacity score
Basis:
mean
Time point:
other: 1 hour, 1, 2, 3 and 7 days
Score:
0
Irritation parameter:
iris score
Basis:
mean
Time point:
other: 1 hour, 1, 2, 3 and 7 days
Score:
0

Any other information on results incl. tables

Immediately following instillation into the eye, all rabbits showed signs of moderate initial pain (grade 4).

Table 1: Eye irritation scores of 2-methyl-2-butene according to the Draize scheme 

Time (hours)

Cornea

Iris

Conjunctiva

Redness

Chemosis

1

1

2

3

4

5

6

1

2

3

4

5

6

1

2

3

4

5

6

1

2

3

4

5

6

24

0

0

0

0

0

0

0

0

0

0

0

0

0.5

0

0

0

0

0.5

0

0

0

0

0

0

48

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

72

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

mean 24-72

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:
2-methyl-2-butene was non irritant to the rabbit eye.
Executive summary:

Instillation of 2-methyl-2-butene into the eye resulted in a moderate initial pain response (grade 4) in all animals. The mean total scores for the responses of the conjunctiva, cornea and iris at 1 hour, 1, 2, 3 and 7 days were calculated and were. 0.5, 0, 0, 0 and 0 respectively.

 

2-Methyl-2-butene may be described as non irritating to rabbit eyes.