4-formyl-2-methoxyphenyl isobutyrate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

19 February - 27 June 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying Ocular Corrosives and Severe Irritants)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

4-formyl-2-methoxyphenyl isobutyrate

EC Number:

243-956-6

EC Name:

4-formyl-2-methoxyphenyl isobutyrate

Cas Number:

20665-85-4

Molecular formula:

C12H14O4

IUPAC Name:

4-formyl-2-methoxyphenyl 2-methylpropanoate

Test material form:

other: liquid

Specific details on test material used for the study:

- Name of test material (as cited in study report): Isobutavan
- Physical state: colourless to pale yellow liquid
- Lot/batch No.: SC00010048
- Expiration date of the lot/batch: December 17, 2015

Test animals / tissue source

Species:

other: Bovine cornea

Strain:

not specified

Details on test animals or tissues and environmental conditions:

Corneas from bovine eyes were obtained from a local abattoir. The eyes were removed after slaughter, completely immersed in Hanks’ Balanced Salt Solution (containing penicillin at 100 IU/mL and streptomycin at 100 μg/mL) in a suitably sized container and transported on the same day to the testing facility. On arrival at the test facility the eyes were carefully examined for defects including increased opacity, scratches and neovascularisation.
Only corneas free from such defects were used.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes

Amount / concentration applied:

The test substance was used as supplied.
A volume of 750 μL of the test article was applied to each of three cornea.
A volume of 750 μL of the negative or positive control

Duration of treatment / exposure:

The test substance was applied for 10 minutes

Duration of post- treatment incubation (in vitro):

Incubation period of 120 minutes at 32°C.

Number of animals or in vitro replicates:

Corneas were tested in triplicate

Results and discussion

In vitro

Results

Results 1

Irritation parameter:

in vitro irritation score

Run / experiment:

Corneal opacity

Value:

0.7

Negative controls validity:

valid

Remarks:

0.0

Positive controls validity:

valid

Remarks:

31.3

Results 2

Irritation parameter:

in vitro irritation score

Run / experiment:

Corneal permeability

Value:

0.032

Negative controls validity:

valid

Remarks:

0.000

Positive controls validity:

valid

Remarks:

0.288

Other effects / acceptance of results:

Two corneas treated with the positive control (numbers 33 and 39) were noted to be cloudy following treatment. The remaining cornea treated with the positive control (number 37) was only cloudy around the edge of the cornea.

In vivo

Irritant / corrosive response data:

The assay showed that the test article, Isobutavan, did not cause serious eye damage.

Applicant's summary and conclusion

Interpretation of results:

not classified

Conclusions:

The test article produced an IVIS score of 1.14 and therefore does not require classification for eye irritation.
The assay was considered valid as the assay acceptance criteria were met.

Executive summary:

The potential of isobutavan to cause eye irritation was evaluated in a BCOP test in accordance to OECD guideline 437 and GLP. A volume of 750 μL of the undiluted test article was applied to each of three corneas followed by a 10 minute incubation at 32°C ± 1°C. After this incubation, each cornea was washed with media containing phenol red followed by media without phenol red and the corneas assessed for opacity. The corneas were then incubated (horizontally) for 2 hours ± 10 minutes after which, corneal opacity was measured and then the anterior chamber emptied. For the permeability endpoint, sodium fluorescein solution was added into the anterior chamber and the corneas were incubated in the vertical position for 1.5 hours ± 5 minutes at 32°C ± 1°C. Following this period, the media in the posterior chamber was removed and three 350 μL aliquots of this media (per cornea) were analysed for optical density at 490 nanometers (OD490). A volume of 750 μL of the negative or positive control was similarly applied to further groups of three corneas. The mean corrected opacity reading for the test article was 0.7, for the negative control was 0.0 and for the positive control was 31.3. The corneas treated with the positive control were noted to be cloudy following treatment. The mean group corrected optical density for the test article was 0.032, for the negative control was 0.000 and for the positive control was 0.288. The test article produced an IVIS score of 1.14. Under the conditions of the in vitro assay, the test substance was considered to be non-irritating to the eye.