Butyl carbamate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From February 16, 1988 to February 23, 1988

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Butyl carbamate

EC Number:

209-751-0

EC Name:

Butyl carbamate

Cas Number:

592-35-8

Molecular formula:

C5H11NO2

IUPAC Name:

butyl carbamate

Test material form:

solid

Details on test material:

organic

Specific details on test material used for the study:

- Butylurethane
- Purity: approx. 94% (impurities: 5.5% dibutyl carbonate, 0.6% n-butanol).
- 100 mg dose

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Remarks:

Albino

Details on test animals or tissues and environmental conditions:

Weight: 2.1 - 3.3 kg
Age: 3 - 5 months
Room temperature: 20 +/- 3°C; Humidity: 50 +/- 20%
Light/dark period: 12/12h
Food: Altromin 2123 Haltungsdiat (ad libitum); Water: deionized (ad libitum)

Test system

Vehicle:

physiological saline

Remarks:

at 37°C

Controls:

yes

Amount / concentration applied:

100 mg

Duration of treatment / exposure:

24 h

Observation period (in vivo):

1, 24, 48, 72 h and 7 days after exposure and washing

Number of animals or in vitro replicates:

3

Details on study design:

A single dose of the test substance was instilled into the cojunctival sac of the left eye.
About 24 h before the start of the experiment, a solution of sodium fluorescein (0.01%) was applied on the cornea in order to assess potential cornea damages.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1.7

Max. score:

3

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Results 2

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Results 3

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2.3

Max. score:

4

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Results 4

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2.7

Max. score:

3

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Results 5

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

3

Max. score:

3

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Results 6

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

3

Max. score:

3

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Results 7

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Max. score:

1

Reversibility:

fully reversible within: 7d

Remarks on result:

positive indication of irritation

Results 8

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1

Max. score:

1

Reversibility:

fully reversible within: 7d

Remarks on result:

positive indication of irritation

Results 9

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1

Max. score:

1

Reversibility:

fully reversible within: 7d

Remarks on result:

positive indication of irritation

Results 10

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1.3

Max. score:

2

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Results 11

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

2

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Results 12

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1.3

Max. score:

2

Reversibility:

not reversible

Remarks on result:

positive indication of irritation

Irritant / corrosive response data:

Observations:
From 1 to 72 h after instillation, the iris was reddened in all of the animals.
One hour to 7 d after instillation, the animals' conjuctivae were slightly swollen to swollen, the eyelids being more than half-closed, and there was hyperaemia which ranged from marked hyperarmia of some of the blood vessels to a diffuse, intense red colour.
The animals' corneas exhibited white discoloration and haemorrhage. Seven days after instillation, all animals were observed to have early or advanced stages of vascularization.
Cornea damages were evaluated in a test with fluorescein with individual scores ranging from 1 to 4 after 24 and 72 h, and 7 d.

Applicant's summary and conclusion

Interpretation of results:

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

Conclusions:

Under the study conditions, the test substance was considered to be severely irritating to rabbit eye.

Executive summary:

A study was conducted to determine the eye irritation potential of the test substance (94% purity) in rabbit according to OECD Guideline 405 and EU Method B.5. The left eye of three New-Zealand White rabbits was exposed to 100 mg of the test substance for 24 h. The right eye remained untreated and served as negative control. After 24 h, the eyes were washed and observations for effects on the cornea, iris and conjunctiva were realized at 1, 24, 48, 72 h and 7 days. The untreated eye served as control. From 1 to 72 h after instillation, the iris was reddened in all of the animals. One hour to 7 days after instillation, conjuctivae were slightly swollen to swollen, the eyelids being more than half-closed, and there was hyperaemia (from marked hyperaemia of some of the blood vessels to a diffuse, intense red colour). The corneas exhibited white discoloration and haemorrhage. Seven days after instillation, all animals were observed to have early or advanced stages of vascularization. Under the study conditions, the test substance was considered to be severely irritating to rabbit eye (Kreiling and Jung, 1988).